diff options
Diffstat (limited to 'kernel/drivers/scsi/atari_NCR5380.c')
| -rw-r--r-- | kernel/drivers/scsi/atari_NCR5380.c | 2927 |
1 files changed, 2927 insertions, 0 deletions
diff --git a/kernel/drivers/scsi/atari_NCR5380.c b/kernel/drivers/scsi/atari_NCR5380.c new file mode 100644 index 000000000..db87ece6e --- /dev/null +++ b/kernel/drivers/scsi/atari_NCR5380.c @@ -0,0 +1,2927 @@ +/* + * NCR 5380 generic driver routines. These should make it *trivial* + * to implement 5380 SCSI drivers under Linux with a non-trantor + * architecture. + * + * Note that these routines also work with NR53c400 family chips. + * + * Copyright 1993, Drew Eckhardt + * Visionary Computing + * (Unix and Linux consulting and custom programming) + * drew@colorado.edu + * +1 (303) 666-5836 + * + * For more information, please consult + * + * NCR 5380 Family + * SCSI Protocol Controller + * Databook + * + * NCR Microelectronics + * 1635 Aeroplaza Drive + * Colorado Springs, CO 80916 + * 1+ (719) 578-3400 + * 1+ (800) 334-5454 + */ + +/* + * ++roman: To port the 5380 driver to the Atari, I had to do some changes in + * this file, too: + * + * - Some of the debug statements were incorrect (undefined variables and the + * like). I fixed that. + * + * - In information_transfer(), I think a #ifdef was wrong. Looking at the + * possible DMA transfer size should also happen for REAL_DMA. I added this + * in the #if statement. + * + * - When using real DMA, information_transfer() should return in a DATAOUT + * phase after starting the DMA. It has nothing more to do. + * + * - The interrupt service routine should run main after end of DMA, too (not + * only after RESELECTION interrupts). Additionally, it should _not_ test + * for more interrupts after running main, since a DMA process may have + * been started and interrupts are turned on now. The new int could happen + * inside the execution of NCR5380_intr(), leading to recursive + * calls. + * + * - I've added a function merge_contiguous_buffers() that tries to + * merge scatter-gather buffers that are located at contiguous + * physical addresses and can be processed with the same DMA setup. + * Since most scatter-gather operations work on a page (4K) of + * 4 buffers (1K), in more than 90% of all cases three interrupts and + * DMA setup actions are saved. + * + * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA + * and USLEEP, because these were messing up readability and will never be + * needed for Atari SCSI. + * + * - I've revised the NCR5380_main() calling scheme (relax the 'main_running' + * stuff), and 'main' is executed in a bottom half if awoken by an + * interrupt. + * + * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..." + * constructs. In my eyes, this made the source rather unreadable, so I + * finally replaced that by the *_PRINTK() macros. + * + */ + +/* + * Further development / testing that should be done : + * 1. Test linked command handling code after Eric is ready with + * the high level code. + */ + +/* Adapted for the sun3 by Sam Creasey. */ + +#include <scsi/scsi_dbg.h> +#include <scsi/scsi_transport_spi.h> + +#if (NDEBUG & NDEBUG_LISTS) +#define LIST(x, y) \ + do { \ + printk("LINE:%d Adding %p to %p\n", \ + __LINE__, (void*)(x), (void*)(y)); \ + if ((x) == (y)) \ + udelay(5); \ + } while (0) +#define REMOVE(w, x, y, z) \ + do { \ + printk("LINE:%d Removing: %p->%p %p->%p \n", \ + __LINE__, (void*)(w), (void*)(x), \ + (void*)(y), (void*)(z)); \ + if ((x) == (y)) \ + udelay(5); \ + } while (0) +#else +#define LIST(x,y) +#define REMOVE(w,x,y,z) +#endif + +#ifndef notyet +#undef LINKED +#endif + +/* + * Design + * + * This is a generic 5380 driver. To use it on a different platform, + * one simply writes appropriate system specific macros (ie, data + * transfer - some PC's will use the I/O bus, 68K's must use + * memory mapped) and drops this file in their 'C' wrapper. + * + * As far as command queueing, two queues are maintained for + * each 5380 in the system - commands that haven't been issued yet, + * and commands that are currently executing. This means that an + * unlimited number of commands may be queued, letting + * more commands propagate from the higher driver levels giving higher + * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported, + * allowing multiple commands to propagate all the way to a SCSI-II device + * while a command is already executing. + * + * + * Issues specific to the NCR5380 : + * + * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead + * piece of hardware that requires you to sit in a loop polling for + * the REQ signal as long as you are connected. Some devices are + * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect + * while doing long seek operations. + * + * The workaround for this is to keep track of devices that have + * disconnected. If the device hasn't disconnected, for commands that + * should disconnect, we do something like + * + * while (!REQ is asserted) { sleep for N usecs; poll for M usecs } + * + * Some tweaking of N and M needs to be done. An algorithm based + * on "time to data" would give the best results as long as short time + * to datas (ie, on the same track) were considered, however these + * broken devices are the exception rather than the rule and I'd rather + * spend my time optimizing for the normal case. + * + * Architecture : + * + * At the heart of the design is a coroutine, NCR5380_main, + * which is started from a workqueue for each NCR5380 host in the + * system. It attempts to establish I_T_L or I_T_L_Q nexuses by + * removing the commands from the issue queue and calling + * NCR5380_select() if a nexus is not established. + * + * Once a nexus is established, the NCR5380_information_transfer() + * phase goes through the various phases as instructed by the target. + * if the target goes into MSG IN and sends a DISCONNECT message, + * the command structure is placed into the per instance disconnected + * queue, and NCR5380_main tries to find more work. If the target is + * idle for too long, the system will try to sleep. + * + * If a command has disconnected, eventually an interrupt will trigger, + * calling NCR5380_intr() which will in turn call NCR5380_reselect + * to reestablish a nexus. This will run main if necessary. + * + * On command termination, the done function will be called as + * appropriate. + * + * SCSI pointers are maintained in the SCp field of SCSI command + * structures, being initialized after the command is connected + * in NCR5380_select, and set as appropriate in NCR5380_information_transfer. + * Note that in violation of the standard, an implicit SAVE POINTERS operation + * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS. + */ + +/* + * Using this file : + * This file a skeleton Linux SCSI driver for the NCR 5380 series + * of chips. To use it, you write an architecture specific functions + * and macros and include this file in your driver. + * + * These macros control options : + * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically + * for commands that return with a CHECK CONDITION status. + * + * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential + * transceivers. + * + * LINKED - if defined, linked commands are supported. + * + * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. + * + * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible + * + * These macros MUST be defined : + * + * NCR5380_read(register) - read from the specified register + * + * NCR5380_write(register, value) - write to the specific register + * + * NCR5380_implementation_fields - additional fields needed for this + * specific implementation of the NCR5380 + * + * Either real DMA *or* pseudo DMA may be implemented + * REAL functions : + * NCR5380_REAL_DMA should be defined if real DMA is to be used. + * Note that the DMA setup functions should return the number of bytes + * that they were able to program the controller for. + * + * Also note that generic i386/PC versions of these macros are + * available as NCR5380_i386_dma_write_setup, + * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual. + * + * NCR5380_dma_write_setup(instance, src, count) - initialize + * NCR5380_dma_read_setup(instance, dst, count) - initialize + * NCR5380_dma_residual(instance); - residual count + * + * PSEUDO functions : + * NCR5380_pwrite(instance, src, count) + * NCR5380_pread(instance, dst, count); + * + * The generic driver is initialized by calling NCR5380_init(instance), + * after setting the appropriate host specific fields and ID. If the + * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance, + * possible) function may be used. + */ + +/* Macros ease life... :-) */ +#define SETUP_HOSTDATA(in) \ + struct NCR5380_hostdata *hostdata = \ + (struct NCR5380_hostdata *)(in)->hostdata +#define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata) + +#define NEXT(cmd) ((struct scsi_cmnd *)(cmd)->host_scribble) +#define SET_NEXT(cmd,next) ((cmd)->host_scribble = (void *)(next)) +#define NEXTADDR(cmd) ((struct scsi_cmnd **)&(cmd)->host_scribble) + +#define HOSTNO instance->host_no +#define H_NO(cmd) (cmd)->device->host->host_no + +#ifdef SUPPORT_TAGS + +/* + * Functions for handling tagged queuing + * ===================================== + * + * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes: + * + * Using consecutive numbers for the tags is no good idea in my eyes. There + * could be wrong re-usings if the counter (8 bit!) wraps and some early + * command has been preempted for a long time. My solution: a bitfield for + * remembering used tags. + * + * There's also the problem that each target has a certain queue size, but we + * cannot know it in advance :-( We just see a QUEUE_FULL status being + * returned. So, in this case, the driver internal queue size assumption is + * reduced to the number of active tags if QUEUE_FULL is returned by the + * target. The command is returned to the mid-level, but with status changed + * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL + * correctly. + * + * We're also not allowed running tagged commands as long as an untagged + * command is active. And REQUEST SENSE commands after a contingent allegiance + * condition _must_ be untagged. To keep track whether an untagged command has + * been issued, the host->busy array is still employed, as it is without + * support for tagged queuing. + * + * One could suspect that there are possible race conditions between + * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the + * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(), + * which already guaranteed to be running at most once. It is also the only + * place where tags/LUNs are allocated. So no other allocation can slip + * between that pair, there could only happen a reselection, which can free a + * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes + * important: the tag bit must be cleared before 'nr_allocated' is decreased. + */ + +static void __init init_tags(struct NCR5380_hostdata *hostdata) +{ + int target, lun; + struct tag_alloc *ta; + + if (!(hostdata->flags & FLAG_TAGGED_QUEUING)) + return; + + for (target = 0; target < 8; ++target) { + for (lun = 0; lun < 8; ++lun) { + ta = &hostdata->TagAlloc[target][lun]; + bitmap_zero(ta->allocated, MAX_TAGS); + ta->nr_allocated = 0; + /* At the beginning, assume the maximum queue size we could + * support (MAX_TAGS). This value will be decreased if the target + * returns QUEUE_FULL status. + */ + ta->queue_size = MAX_TAGS; + } + } +} + + +/* Check if we can issue a command to this LUN: First see if the LUN is marked + * busy by an untagged command. If the command should use tagged queuing, also + * check that there is a free tag and the target's queue won't overflow. This + * function should be called with interrupts disabled to avoid race + * conditions. + */ + +static int is_lun_busy(struct scsi_cmnd *cmd, int should_be_tagged) +{ + u8 lun = cmd->device->lun; + SETUP_HOSTDATA(cmd->device->host); + + if (hostdata->busy[cmd->device->id] & (1 << lun)) + return 1; + if (!should_be_tagged || + !(hostdata->flags & FLAG_TAGGED_QUEUING) || + !cmd->device->tagged_supported) + return 0; + if (hostdata->TagAlloc[scmd_id(cmd)][lun].nr_allocated >= + hostdata->TagAlloc[scmd_id(cmd)][lun].queue_size) { + dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d: no free tags\n", + H_NO(cmd), cmd->device->id, lun); + return 1; + } + return 0; +} + + +/* Allocate a tag for a command (there are no checks anymore, check_lun_busy() + * must be called before!), or reserve the LUN in 'busy' if the command is + * untagged. + */ + +static void cmd_get_tag(struct scsi_cmnd *cmd, int should_be_tagged) +{ + u8 lun = cmd->device->lun; + SETUP_HOSTDATA(cmd->device->host); + + /* If we or the target don't support tagged queuing, allocate the LUN for + * an untagged command. + */ + if (!should_be_tagged || + !(hostdata->flags & FLAG_TAGGED_QUEUING) || + !cmd->device->tagged_supported) { + cmd->tag = TAG_NONE; + hostdata->busy[cmd->device->id] |= (1 << lun); + dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d now allocated by untagged " + "command\n", H_NO(cmd), cmd->device->id, lun); + } else { + struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun]; + + cmd->tag = find_first_zero_bit(ta->allocated, MAX_TAGS); + set_bit(cmd->tag, ta->allocated); + ta->nr_allocated++; + dprintk(NDEBUG_TAGS, "scsi%d: using tag %d for target %d lun %d " + "(now %d tags in use)\n", + H_NO(cmd), cmd->tag, cmd->device->id, + lun, ta->nr_allocated); + } +} + + +/* Mark the tag of command 'cmd' as free, or in case of an untagged command, + * unlock the LUN. + */ + +static void cmd_free_tag(struct scsi_cmnd *cmd) +{ + u8 lun = cmd->device->lun; + SETUP_HOSTDATA(cmd->device->host); + + if (cmd->tag == TAG_NONE) { + hostdata->busy[cmd->device->id] &= ~(1 << lun); + dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d untagged cmd finished\n", + H_NO(cmd), cmd->device->id, lun); + } else if (cmd->tag >= MAX_TAGS) { + printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n", + H_NO(cmd), cmd->tag); + } else { + struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun]; + clear_bit(cmd->tag, ta->allocated); + ta->nr_allocated--; + dprintk(NDEBUG_TAGS, "scsi%d: freed tag %d for target %d lun %d\n", + H_NO(cmd), cmd->tag, cmd->device->id, lun); + } +} + + +static void free_all_tags(struct NCR5380_hostdata *hostdata) +{ + int target, lun; + struct tag_alloc *ta; + + if (!(hostdata->flags & FLAG_TAGGED_QUEUING)) + return; + + for (target = 0; target < 8; ++target) { + for (lun = 0; lun < 8; ++lun) { + ta = &hostdata->TagAlloc[target][lun]; + bitmap_zero(ta->allocated, MAX_TAGS); + ta->nr_allocated = 0; + } + } +} + +#endif /* SUPPORT_TAGS */ + + +/* + * Function: void merge_contiguous_buffers( struct scsi_cmnd *cmd ) + * + * Purpose: Try to merge several scatter-gather requests into one DMA + * transfer. This is possible if the scatter buffers lie on + * physical contiguous addresses. + * + * Parameters: struct scsi_cmnd *cmd + * The command to work on. The first scatter buffer's data are + * assumed to be already transferred into ptr/this_residual. + */ + +static void merge_contiguous_buffers(struct scsi_cmnd *cmd) +{ +#if !defined(CONFIG_SUN3) + unsigned long endaddr; +#if (NDEBUG & NDEBUG_MERGING) + unsigned long oldlen = cmd->SCp.this_residual; + int cnt = 1; +#endif + + for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1; + cmd->SCp.buffers_residual && + virt_to_phys(sg_virt(&cmd->SCp.buffer[1])) == endaddr;) { + dprintk(NDEBUG_MERGING, "VTOP(%p) == %08lx -> merging\n", + page_address(sg_page(&cmd->SCp.buffer[1])), endaddr); +#if (NDEBUG & NDEBUG_MERGING) + ++cnt; +#endif + ++cmd->SCp.buffer; + --cmd->SCp.buffers_residual; + cmd->SCp.this_residual += cmd->SCp.buffer->length; + endaddr += cmd->SCp.buffer->length; + } +#if (NDEBUG & NDEBUG_MERGING) + if (oldlen != cmd->SCp.this_residual) + dprintk(NDEBUG_MERGING, "merged %d buffers from %p, new length %08x\n", + cnt, cmd->SCp.ptr, cmd->SCp.this_residual); +#endif +#endif /* !defined(CONFIG_SUN3) */ +} + +/** + * initialize_SCp - init the scsi pointer field + * @cmd: command block to set up + * + * Set up the internal fields in the SCSI command. + */ + +static inline void initialize_SCp(struct scsi_cmnd *cmd) +{ + /* + * Initialize the Scsi Pointer field so that all of the commands in the + * various queues are valid. + */ + + if (scsi_bufflen(cmd)) { + cmd->SCp.buffer = scsi_sglist(cmd); + cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1; + cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); + cmd->SCp.this_residual = cmd->SCp.buffer->length; + /* ++roman: Try to merge some scatter-buffers if they are at + * contiguous physical addresses. + */ + merge_contiguous_buffers(cmd); + } else { + cmd->SCp.buffer = NULL; + cmd->SCp.buffers_residual = 0; + cmd->SCp.ptr = NULL; + cmd->SCp.this_residual = 0; + } +} + +#include <linux/delay.h> + +#if NDEBUG +static struct { + unsigned char mask; + const char *name; +} signals[] = { + { SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" }, + { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" }, + { SR_SEL, "SEL" }, {0, NULL} +}, basrs[] = { + {BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL} +}, icrs[] = { + {ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"}, + {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"}, + {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"}, + {0, NULL} +}, mrs[] = { + {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"}, + {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR, + "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"}, + {MR_MONITOR_BSY, "MODE MONITOR BSY"}, + {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"}, + {0, NULL} +}; + +/** + * NCR5380_print - print scsi bus signals + * @instance: adapter state to dump + * + * Print the SCSI bus signals for debugging purposes + */ + +static void NCR5380_print(struct Scsi_Host *instance) +{ + unsigned char status, data, basr, mr, icr, i; + unsigned long flags; + + local_irq_save(flags); + data = NCR5380_read(CURRENT_SCSI_DATA_REG); + status = NCR5380_read(STATUS_REG); + mr = NCR5380_read(MODE_REG); + icr = NCR5380_read(INITIATOR_COMMAND_REG); + basr = NCR5380_read(BUS_AND_STATUS_REG); + local_irq_restore(flags); + printk("STATUS_REG: %02x ", status); + for (i = 0; signals[i].mask; ++i) + if (status & signals[i].mask) + printk(",%s", signals[i].name); + printk("\nBASR: %02x ", basr); + for (i = 0; basrs[i].mask; ++i) + if (basr & basrs[i].mask) + printk(",%s", basrs[i].name); + printk("\nICR: %02x ", icr); + for (i = 0; icrs[i].mask; ++i) + if (icr & icrs[i].mask) + printk(",%s", icrs[i].name); + printk("\nMODE: %02x ", mr); + for (i = 0; mrs[i].mask; ++i) + if (mr & mrs[i].mask) + printk(",%s", mrs[i].name); + printk("\n"); +} + +static struct { + unsigned char value; + const char *name; +} phases[] = { + {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"}, + {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"}, + {PHASE_UNKNOWN, "UNKNOWN"} +}; + +/** + * NCR5380_print_phase - show SCSI phase + * @instance: adapter to dump + * + * Print the current SCSI phase for debugging purposes + * + * Locks: none + */ + +static void NCR5380_print_phase(struct Scsi_Host *instance) +{ + unsigned char status; + int i; + + status = NCR5380_read(STATUS_REG); + if (!(status & SR_REQ)) + printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO); + else { + for (i = 0; (phases[i].value != PHASE_UNKNOWN) && + (phases[i].value != (status & PHASE_MASK)); ++i) + ; + printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name); + } +} + +#endif + +/* + * ++roman: New scheme of calling NCR5380_main() + * + * If we're not in an interrupt, we can call our main directly, it cannot be + * already running. Else, we queue it on a task queue, if not 'main_running' + * tells us that a lower level is already executing it. This way, + * 'main_running' needs not be protected in a special way. + * + * queue_main() is a utility function for putting our main onto the task + * queue, if main_running is false. It should be called only from a + * interrupt or bottom half. + */ + +#include <linux/gfp.h> +#include <linux/workqueue.h> +#include <linux/interrupt.h> + +static inline void queue_main(struct NCR5380_hostdata *hostdata) +{ + if (!hostdata->main_running) { + /* If in interrupt and NCR5380_main() not already running, + queue it on the 'immediate' task queue, to be processed + immediately after the current interrupt processing has + finished. */ + schedule_work(&hostdata->main_task); + } + /* else: nothing to do: the running NCR5380_main() will pick up + any newly queued command. */ +} + +/** + * NCR58380_info - report driver and host information + * @instance: relevant scsi host instance + * + * For use as the host template info() handler. + * + * Locks: none + */ + +static const char *NCR5380_info(struct Scsi_Host *instance) +{ + struct NCR5380_hostdata *hostdata = shost_priv(instance); + + return hostdata->info; +} + +static void prepare_info(struct Scsi_Host *instance) +{ + struct NCR5380_hostdata *hostdata = shost_priv(instance); + + snprintf(hostdata->info, sizeof(hostdata->info), + "%s, io_port 0x%lx, n_io_port %d, " + "base 0x%lx, irq %d, " + "can_queue %d, cmd_per_lun %d, " + "sg_tablesize %d, this_id %d, " + "flags { %s}, " + "options { %s} ", + instance->hostt->name, instance->io_port, instance->n_io_port, + instance->base, instance->irq, + instance->can_queue, instance->cmd_per_lun, + instance->sg_tablesize, instance->this_id, + hostdata->flags & FLAG_TAGGED_QUEUING ? "TAGGED_QUEUING " : "", +#ifdef DIFFERENTIAL + "DIFFERENTIAL " +#endif +#ifdef REAL_DMA + "REAL_DMA " +#endif +#ifdef PARITY + "PARITY " +#endif +#ifdef SUPPORT_TAGS + "SUPPORT_TAGS " +#endif + ""); +} + +/** + * NCR5380_print_status - dump controller info + * @instance: controller to dump + * + * Print commands in the various queues, called from NCR5380_abort + * to aid debugging. + */ + +static void lprint_Scsi_Cmnd(struct scsi_cmnd *cmd) +{ + int i, s; + unsigned char *command; + printk("scsi%d: destination target %d, lun %llu\n", + H_NO(cmd), cmd->device->id, cmd->device->lun); + printk(KERN_CONT " command = "); + command = cmd->cmnd; + printk(KERN_CONT "%2d (0x%02x)", command[0], command[0]); + for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) + printk(KERN_CONT " %02x", command[i]); + printk("\n"); +} + +static void NCR5380_print_status(struct Scsi_Host *instance) +{ + struct NCR5380_hostdata *hostdata; + struct scsi_cmnd *ptr; + unsigned long flags; + + NCR5380_dprint(NDEBUG_ANY, instance); + NCR5380_dprint_phase(NDEBUG_ANY, instance); + + hostdata = (struct NCR5380_hostdata *)instance->hostdata; + + local_irq_save(flags); + printk("NCR5380: coroutine is%s running.\n", + hostdata->main_running ? "" : "n't"); + if (!hostdata->connected) + printk("scsi%d: no currently connected command\n", HOSTNO); + else + lprint_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected); + printk("scsi%d: issue_queue\n", HOSTNO); + for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) + lprint_Scsi_Cmnd(ptr); + + printk("scsi%d: disconnected_queue\n", HOSTNO); + for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr; + ptr = NEXT(ptr)) + lprint_Scsi_Cmnd(ptr); + + local_irq_restore(flags); + printk("\n"); +} + +static void show_Scsi_Cmnd(struct scsi_cmnd *cmd, struct seq_file *m) +{ + int i, s; + unsigned char *command; + seq_printf(m, "scsi%d: destination target %d, lun %llu\n", + H_NO(cmd), cmd->device->id, cmd->device->lun); + seq_puts(m, " command = "); + command = cmd->cmnd; + seq_printf(m, "%2d (0x%02x)", command[0], command[0]); + for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) + seq_printf(m, " %02x", command[i]); + seq_putc(m, '\n'); +} + +static int __maybe_unused NCR5380_show_info(struct seq_file *m, + struct Scsi_Host *instance) +{ + struct NCR5380_hostdata *hostdata; + struct scsi_cmnd *ptr; + unsigned long flags; + + hostdata = (struct NCR5380_hostdata *)instance->hostdata; + + local_irq_save(flags); + seq_printf(m, "NCR5380: coroutine is%s running.\n", + hostdata->main_running ? "" : "n't"); + if (!hostdata->connected) + seq_printf(m, "scsi%d: no currently connected command\n", HOSTNO); + else + show_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected, m); + seq_printf(m, "scsi%d: issue_queue\n", HOSTNO); + for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) + show_Scsi_Cmnd(ptr, m); + + seq_printf(m, "scsi%d: disconnected_queue\n", HOSTNO); + for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr; + ptr = NEXT(ptr)) + show_Scsi_Cmnd(ptr, m); + + local_irq_restore(flags); + return 0; +} + +/** + * NCR5380_init - initialise an NCR5380 + * @instance: adapter to configure + * @flags: control flags + * + * Initializes *instance and corresponding 5380 chip, + * with flags OR'd into the initial flags value. + * + * Notes : I assume that the host, hostno, and id bits have been + * set correctly. I don't care about the irq and other fields. + * + * Returns 0 for success + */ + +static int __init NCR5380_init(struct Scsi_Host *instance, int flags) +{ + int i; + SETUP_HOSTDATA(instance); + + hostdata->host = instance; + hostdata->aborted = 0; + hostdata->id_mask = 1 << instance->this_id; + hostdata->id_higher_mask = 0; + for (i = hostdata->id_mask; i <= 0x80; i <<= 1) + if (i > hostdata->id_mask) + hostdata->id_higher_mask |= i; + for (i = 0; i < 8; ++i) + hostdata->busy[i] = 0; +#ifdef SUPPORT_TAGS + init_tags(hostdata); +#endif +#if defined (REAL_DMA) + hostdata->dma_len = 0; +#endif + hostdata->targets_present = 0; + hostdata->connected = NULL; + hostdata->issue_queue = NULL; + hostdata->disconnected_queue = NULL; + hostdata->flags = flags; + + INIT_WORK(&hostdata->main_task, NCR5380_main); + + prepare_info(instance); + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(TARGET_COMMAND_REG, 0); + NCR5380_write(SELECT_ENABLE_REG, 0); + + return 0; +} + +/** + * NCR5380_exit - remove an NCR5380 + * @instance: adapter to remove + * + * Assumes that no more work can be queued (e.g. by NCR5380_intr). + */ + +static void NCR5380_exit(struct Scsi_Host *instance) +{ + struct NCR5380_hostdata *hostdata = shost_priv(instance); + + cancel_work_sync(&hostdata->main_task); +} + +/** + * NCR5380_queue_command - queue a command + * @instance: the relevant SCSI adapter + * @cmd: SCSI command + * + * cmd is added to the per instance issue_queue, with minor + * twiddling done to the host specific fields of cmd. If the + * main coroutine is not running, it is restarted. + */ + +static int NCR5380_queue_command(struct Scsi_Host *instance, + struct scsi_cmnd *cmd) +{ + struct NCR5380_hostdata *hostdata = shost_priv(instance); + struct scsi_cmnd *tmp; + unsigned long flags; + +#if (NDEBUG & NDEBUG_NO_WRITE) + switch (cmd->cmnd[0]) { + case WRITE_6: + case WRITE_10: + printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n", + H_NO(cmd)); + cmd->result = (DID_ERROR << 16); + cmd->scsi_done(cmd); + return 0; + } +#endif /* (NDEBUG & NDEBUG_NO_WRITE) */ + + /* + * We use the host_scribble field as a pointer to the next command + * in a queue + */ + + SET_NEXT(cmd, NULL); + cmd->result = 0; + + /* + * Insert the cmd into the issue queue. Note that REQUEST SENSE + * commands are added to the head of the queue since any command will + * clear the contingent allegiance condition that exists and the + * sense data is only guaranteed to be valid while the condition exists. + */ + + /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA. + * Otherwise a running NCR5380_main may steal the lock. + * Lock before actually inserting due to fairness reasons explained in + * atari_scsi.c. If we insert first, then it's impossible for this driver + * to release the lock. + * Stop timer for this command while waiting for the lock, or timeouts + * may happen (and they really do), and it's no good if the command doesn't + * appear in any of the queues. + * ++roman: Just disabling the NCR interrupt isn't sufficient here, + * because also a timer int can trigger an abort or reset, which would + * alter queues and touch the lock. + */ + if (!NCR5380_acquire_dma_irq(instance)) + return SCSI_MLQUEUE_HOST_BUSY; + + local_irq_save(flags); + + /* + * Insert the cmd into the issue queue. Note that REQUEST SENSE + * commands are added to the head of the queue since any command will + * clear the contingent allegiance condition that exists and the + * sense data is only guaranteed to be valid while the condition exists. + */ + + if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) { + LIST(cmd, hostdata->issue_queue); + SET_NEXT(cmd, hostdata->issue_queue); + hostdata->issue_queue = cmd; + } else { + for (tmp = (struct scsi_cmnd *)hostdata->issue_queue; + NEXT(tmp); tmp = NEXT(tmp)) + ; + LIST(cmd, tmp); + SET_NEXT(tmp, cmd); + } + local_irq_restore(flags); + + dprintk(NDEBUG_QUEUES, "scsi%d: command added to %s of queue\n", H_NO(cmd), + (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"); + + /* If queue_command() is called from an interrupt (real one or bottom + * half), we let queue_main() do the job of taking care about main. If it + * is already running, this is a no-op, else main will be queued. + * + * If we're not in an interrupt, we can call NCR5380_main() + * unconditionally, because it cannot be already running. + */ + if (in_interrupt() || irqs_disabled()) + queue_main(hostdata); + else + NCR5380_main(&hostdata->main_task); + return 0; +} + +static inline void maybe_release_dma_irq(struct Scsi_Host *instance) +{ + struct NCR5380_hostdata *hostdata = shost_priv(instance); + + /* Caller does the locking needed to set & test these data atomically */ + if (!hostdata->disconnected_queue && + !hostdata->issue_queue && + !hostdata->connected && + !hostdata->retain_dma_intr) + NCR5380_release_dma_irq(instance); +} + +/** + * NCR5380_main - NCR state machines + * + * NCR5380_main is a coroutine that runs as long as more work can + * be done on the NCR5380 host adapters in a system. Both + * NCR5380_queue_command() and NCR5380_intr() will try to start it + * in case it is not running. + * + * Locks: called as its own thread with no locks held. + */ + +static void NCR5380_main(struct work_struct *work) +{ + struct NCR5380_hostdata *hostdata = + container_of(work, struct NCR5380_hostdata, main_task); + struct Scsi_Host *instance = hostdata->host; + struct scsi_cmnd *tmp, *prev; + int done; + unsigned long flags; + + /* + * We run (with interrupts disabled) until we're sure that none of + * the host adapters have anything that can be done, at which point + * we set main_running to 0 and exit. + * + * Interrupts are enabled before doing various other internal + * instructions, after we've decided that we need to run through + * the loop again. + * + * this should prevent any race conditions. + * + * ++roman: Just disabling the NCR interrupt isn't sufficient here, + * because also a timer int can trigger an abort or reset, which can + * alter queues and touch the Falcon lock. + */ + + /* Tell int handlers main() is now already executing. Note that + no races are possible here. If an int comes in before + 'main_running' is set here, and queues/executes main via the + task queue, it doesn't do any harm, just this instance of main + won't find any work left to do. */ + if (hostdata->main_running) + return; + hostdata->main_running = 1; + + local_save_flags(flags); + do { + local_irq_disable(); /* Freeze request queues */ + done = 1; + + if (!hostdata->connected) { + dprintk(NDEBUG_MAIN, "scsi%d: not connected\n", HOSTNO); + /* + * Search through the issue_queue for a command destined + * for a target that's not busy. + */ +#if (NDEBUG & NDEBUG_LISTS) + for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, prev = NULL; + tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp)) + ; + /*printk("%p ", tmp);*/ + if ((tmp == prev) && tmp) + printk(" LOOP\n"); + /* else printk("\n"); */ +#endif + for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, + prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) { + u8 lun = tmp->device->lun; + + dprintk(NDEBUG_LISTS, + "MAIN tmp=%p target=%d busy=%d lun=%d\n", + tmp, scmd_id(tmp), hostdata->busy[scmd_id(tmp)], + lun); + /* When we find one, remove it from the issue queue. */ + /* ++guenther: possible race with Falcon locking */ + if ( +#ifdef SUPPORT_TAGS + !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE) +#else + !(hostdata->busy[tmp->device->id] & (1 << lun)) +#endif + ) { + /* ++guenther: just to be sure, this must be atomic */ + local_irq_disable(); + if (prev) { + REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); + SET_NEXT(prev, NEXT(tmp)); + } else { + REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp)); + hostdata->issue_queue = NEXT(tmp); + } + SET_NEXT(tmp, NULL); + hostdata->retain_dma_intr++; + + /* reenable interrupts after finding one */ + local_irq_restore(flags); + + /* + * Attempt to establish an I_T_L nexus here. + * On success, instance->hostdata->connected is set. + * On failure, we must add the command back to the + * issue queue so we can keep trying. + */ + dprintk(NDEBUG_MAIN, "scsi%d: main(): command for target %d " + "lun %d removed from issue_queue\n", + HOSTNO, tmp->device->id, lun); + /* + * REQUEST SENSE commands are issued without tagged + * queueing, even on SCSI-II devices because the + * contingent allegiance condition exists for the + * entire unit. + */ + /* ++roman: ...and the standard also requires that + * REQUEST SENSE command are untagged. + */ + +#ifdef SUPPORT_TAGS + cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE); +#endif + if (!NCR5380_select(instance, tmp)) { + local_irq_disable(); + hostdata->retain_dma_intr--; + /* release if target did not response! */ + maybe_release_dma_irq(instance); + local_irq_restore(flags); + break; + } else { + local_irq_disable(); + LIST(tmp, hostdata->issue_queue); + SET_NEXT(tmp, hostdata->issue_queue); + hostdata->issue_queue = tmp; +#ifdef SUPPORT_TAGS + cmd_free_tag(tmp); +#endif + hostdata->retain_dma_intr--; + local_irq_restore(flags); + dprintk(NDEBUG_MAIN, "scsi%d: main(): select() failed, " + "returned to issue_queue\n", HOSTNO); + if (hostdata->connected) + break; + } + } /* if target/lun/target queue is not busy */ + } /* for issue_queue */ + } /* if (!hostdata->connected) */ + + if (hostdata->connected +#ifdef REAL_DMA + && !hostdata->dma_len +#endif + ) { + local_irq_restore(flags); + dprintk(NDEBUG_MAIN, "scsi%d: main: performing information transfer\n", + HOSTNO); + NCR5380_information_transfer(instance); + dprintk(NDEBUG_MAIN, "scsi%d: main: done set false\n", HOSTNO); + done = 0; + } + } while (!done); + + /* Better allow ints _after_ 'main_running' has been cleared, else + an interrupt could believe we'll pick up the work it left for + us, but we won't see it anymore here... */ + hostdata->main_running = 0; + local_irq_restore(flags); +} + + +#ifdef REAL_DMA +/* + * Function : void NCR5380_dma_complete (struct Scsi_Host *instance) + * + * Purpose : Called by interrupt handler when DMA finishes or a phase + * mismatch occurs (which would finish the DMA transfer). + * + * Inputs : instance - this instance of the NCR5380. + * + */ + +static void NCR5380_dma_complete(struct Scsi_Host *instance) +{ + SETUP_HOSTDATA(instance); + int transferred; + unsigned char **data; + volatile int *count; + int saved_data = 0, overrun = 0; + unsigned char p; + + if (!hostdata->connected) { + printk(KERN_WARNING "scsi%d: received end of DMA interrupt with " + "no connected cmd\n", HOSTNO); + return; + } + + if (hostdata->read_overruns) { + p = hostdata->connected->SCp.phase; + if (p & SR_IO) { + udelay(10); + if ((NCR5380_read(BUS_AND_STATUS_REG) & + (BASR_PHASE_MATCH|BASR_ACK)) == + (BASR_PHASE_MATCH|BASR_ACK)) { + saved_data = NCR5380_read(INPUT_DATA_REG); + overrun = 1; + dprintk(NDEBUG_DMA, "scsi%d: read overrun handled\n", HOSTNO); + } + } + } + + dprintk(NDEBUG_DMA, "scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n", + HOSTNO, NCR5380_read(BUS_AND_STATUS_REG), + NCR5380_read(STATUS_REG)); + +#if defined(CONFIG_SUN3) + if ((sun3scsi_dma_finish(rq_data_dir(hostdata->connected->request)))) { + pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n", + instance->host_no); + BUG(); + } + + /* make sure we're not stuck in a data phase */ + if ((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == + (BASR_PHASE_MATCH | BASR_ACK)) { + pr_err("scsi%d: BASR %02x\n", instance->host_no, + NCR5380_read(BUS_AND_STATUS_REG)); + pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n", + instance->host_no); + BUG(); + } +#endif + + (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + + transferred = hostdata->dma_len - NCR5380_dma_residual(instance); + hostdata->dma_len = 0; + + data = (unsigned char **)&hostdata->connected->SCp.ptr; + count = &hostdata->connected->SCp.this_residual; + *data += transferred; + *count -= transferred; + + if (hostdata->read_overruns) { + int cnt, toPIO; + + if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) { + cnt = toPIO = hostdata->read_overruns; + if (overrun) { + dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n"); + *(*data)++ = saved_data; + (*count)--; + cnt--; + toPIO--; + } + dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data); + NCR5380_transfer_pio(instance, &p, &cnt, data); + *count -= toPIO - cnt; + } + } +} +#endif /* REAL_DMA */ + + +/** + * NCR5380_intr - generic NCR5380 irq handler + * @irq: interrupt number + * @dev_id: device info + * + * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses + * from the disconnected queue, and restarting NCR5380_main() + * as required. + */ + +static irqreturn_t NCR5380_intr(int irq, void *dev_id) +{ + struct Scsi_Host *instance = dev_id; + int done = 1, handled = 0; + unsigned char basr; + + dprintk(NDEBUG_INTR, "scsi%d: NCR5380 irq triggered\n", HOSTNO); + + /* Look for pending interrupts */ + basr = NCR5380_read(BUS_AND_STATUS_REG); + dprintk(NDEBUG_INTR, "scsi%d: BASR=%02x\n", HOSTNO, basr); + /* dispatch to appropriate routine if found and done=0 */ + if (basr & BASR_IRQ) { + NCR5380_dprint(NDEBUG_INTR, instance); + if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) { + done = 0; + dprintk(NDEBUG_INTR, "scsi%d: SEL interrupt\n", HOSTNO); + NCR5380_reselect(instance); + (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); + } else if (basr & BASR_PARITY_ERROR) { + dprintk(NDEBUG_INTR, "scsi%d: PARITY interrupt\n", HOSTNO); + (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); + } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) { + dprintk(NDEBUG_INTR, "scsi%d: RESET interrupt\n", HOSTNO); + (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); + } else { + /* + * The rest of the interrupt conditions can occur only during a + * DMA transfer + */ + +#if defined(REAL_DMA) + /* + * We should only get PHASE MISMATCH and EOP interrupts if we have + * DMA enabled, so do a sanity check based on the current setting + * of the MODE register. + */ + + if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) && + ((basr & BASR_END_DMA_TRANSFER) || + !(basr & BASR_PHASE_MATCH))) { + + dprintk(NDEBUG_INTR, "scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO); + NCR5380_dma_complete( instance ); + done = 0; + } else +#endif /* REAL_DMA */ + { +/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */ + if (basr & BASR_PHASE_MATCH) + dprintk(NDEBUG_INTR, "scsi%d: unknown interrupt, " + "BASR 0x%x, MR 0x%x, SR 0x%x\n", + HOSTNO, basr, NCR5380_read(MODE_REG), + NCR5380_read(STATUS_REG)); + (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); +#ifdef SUN3_SCSI_VME + dregs->csr |= CSR_DMA_ENABLE; +#endif + } + } /* if !(SELECTION || PARITY) */ + handled = 1; + } /* BASR & IRQ */ else { + printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, " + "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr, + NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)); + (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); +#ifdef SUN3_SCSI_VME + dregs->csr |= CSR_DMA_ENABLE; +#endif + } + + if (!done) { + dprintk(NDEBUG_INTR, "scsi%d: in int routine, calling main\n", HOSTNO); + /* Put a call to NCR5380_main() on the queue... */ + queue_main(shost_priv(instance)); + } + return IRQ_RETVAL(handled); +} + +/* + * Function : int NCR5380_select(struct Scsi_Host *instance, + * struct scsi_cmnd *cmd) + * + * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command, + * including ARBITRATION, SELECTION, and initial message out for + * IDENTIFY and queue messages. + * + * Inputs : instance - instantiation of the 5380 driver on which this + * target lives, cmd - SCSI command to execute. + * + * Returns : -1 if selection could not execute for some reason, + * 0 if selection succeeded or failed because the target + * did not respond. + * + * Side effects : + * If bus busy, arbitration failed, etc, NCR5380_select() will exit + * with registers as they should have been on entry - ie + * SELECT_ENABLE will be set appropriately, the NCR5380 + * will cease to drive any SCSI bus signals. + * + * If successful : I_T_L or I_T_L_Q nexus will be established, + * instance->connected will be set to cmd. + * SELECT interrupt will be disabled. + * + * If failed (no target) : cmd->scsi_done() will be called, and the + * cmd->result host byte set to DID_BAD_TARGET. + */ + +static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) +{ + SETUP_HOSTDATA(instance); + unsigned char tmp[3], phase; + unsigned char *data; + int len; + unsigned long timeout; + unsigned long flags; + + hostdata->restart_select = 0; + NCR5380_dprint(NDEBUG_ARBITRATION, instance); + dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", HOSTNO, + instance->this_id); + + /* + * Set the phase bits to 0, otherwise the NCR5380 won't drive the + * data bus during SELECTION. + */ + + local_irq_save(flags); + if (hostdata->connected) { + local_irq_restore(flags); + return -1; + } + NCR5380_write(TARGET_COMMAND_REG, 0); + + /* + * Start arbitration. + */ + + NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); + NCR5380_write(MODE_REG, MR_ARBITRATE); + + local_irq_restore(flags); + + /* Wait for arbitration logic to complete */ +#if defined(NCR_TIMEOUT) + { + unsigned long timeout = jiffies + 2*NCR_TIMEOUT; + + while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) && + time_before(jiffies, timeout) && !hostdata->connected) + ; + if (time_after_eq(jiffies, timeout)) { + printk("scsi : arbitration timeout at %d\n", __LINE__); + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + return -1; + } + } +#else /* NCR_TIMEOUT */ + while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) && + !hostdata->connected) + ; +#endif + + dprintk(NDEBUG_ARBITRATION, "scsi%d: arbitration complete\n", HOSTNO); + + if (hostdata->connected) { + NCR5380_write(MODE_REG, MR_BASE); + return -1; + } + /* + * The arbitration delay is 2.2us, but this is a minimum and there is + * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate + * the integral nature of udelay(). + * + */ + + udelay(3); + + /* Check for lost arbitration */ + if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || + (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || + (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || + hostdata->connected) { + NCR5380_write(MODE_REG, MR_BASE); + dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n", + HOSTNO); + return -1; + } + + /* after/during arbitration, BSY should be asserted. + IBM DPES-31080 Version S31Q works now */ + /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */ + NCR5380_write(INITIATOR_COMMAND_REG, + ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY); + + if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || + hostdata->connected) { + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n", + HOSTNO); + return -1; + } + + /* + * Again, bus clear + bus settle time is 1.2us, however, this is + * a minimum so we'll udelay ceil(1.2) + */ + +#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY + /* ++roman: But some targets (see above :-) seem to need a bit more... */ + udelay(15); +#else + udelay(2); +#endif + + if (hostdata->connected) { + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + return -1; + } + + dprintk(NDEBUG_ARBITRATION, "scsi%d: won arbitration\n", HOSTNO); + + /* + * Now that we have won arbitration, start Selection process, asserting + * the host and target ID's on the SCSI bus. + */ + + NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id))); + + /* + * Raise ATN while SEL is true before BSY goes false from arbitration, + * since this is the only way to guarantee that we'll get a MESSAGE OUT + * phase immediately after selection. + */ + + NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | + ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL )); + NCR5380_write(MODE_REG, MR_BASE); + + /* + * Reselect interrupts must be turned off prior to the dropping of BSY, + * otherwise we will trigger an interrupt. + */ + + if (hostdata->connected) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + return -1; + } + + NCR5380_write(SELECT_ENABLE_REG, 0); + + /* + * The initiator shall then wait at least two deskew delays and release + * the BSY signal. + */ + udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */ + + /* Reset BSY */ + NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | + ICR_ASSERT_ATN | ICR_ASSERT_SEL)); + + /* + * Something weird happens when we cease to drive BSY - looks + * like the board/chip is letting us do another read before the + * appropriate propagation delay has expired, and we're confusing + * a BSY signal from ourselves as the target's response to SELECTION. + * + * A small delay (the 'C++' frontend breaks the pipeline with an + * unnecessary jump, making it work on my 386-33/Trantor T128, the + * tighter 'C' code breaks and requires this) solves the problem - + * the 1 us delay is arbitrary, and only used because this delay will + * be the same on other platforms and since it works here, it should + * work there. + * + * wingel suggests that this could be due to failing to wait + * one deskew delay. + */ + + udelay(1); + + dprintk(NDEBUG_SELECTION, "scsi%d: selecting target %d\n", HOSTNO, cmd->device->id); + + /* + * The SCSI specification calls for a 250 ms timeout for the actual + * selection. + */ + + timeout = jiffies + msecs_to_jiffies(250); + + /* + * XXX very interesting - we're seeing a bounce where the BSY we + * asserted is being reflected / still asserted (propagation delay?) + * and it's detecting as true. Sigh. + */ + +#if 0 + /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert + * IO while SEL is true. But again, there are some disks out the in the + * world that do that nevertheless. (Somebody claimed that this announces + * reselection capability of the target.) So we better skip that test and + * only wait for BSY... (Famous german words: Der Klügere gibt nach :-) + */ + + while (time_before(jiffies, timeout) && + !(NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO))) + ; + + if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + NCR5380_reselect(instance); + printk(KERN_ERR "scsi%d: reselection after won arbitration?\n", + HOSTNO); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + return -1; + } +#else + while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY)) + ; +#endif + + /* + * No less than two deskew delays after the initiator detects the + * BSY signal is true, it shall release the SEL signal and may + * change the DATA BUS. -wingel + */ + + udelay(1); + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); + + if (!(NCR5380_read(STATUS_REG) & SR_BSY)) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + if (hostdata->targets_present & (1 << cmd->device->id)) { + printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO); + if (hostdata->restart_select) + printk(KERN_NOTICE "\trestart select\n"); + NCR5380_dprint(NDEBUG_ANY, instance); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + return -1; + } + cmd->result = DID_BAD_TARGET << 16; +#ifdef SUPPORT_TAGS + cmd_free_tag(cmd); +#endif + cmd->scsi_done(cmd); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + dprintk(NDEBUG_SELECTION, "scsi%d: target did not respond within 250ms\n", HOSTNO); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + return 0; + } + + hostdata->targets_present |= (1 << cmd->device->id); + + /* + * Since we followed the SCSI spec, and raised ATN while SEL + * was true but before BSY was false during selection, the information + * transfer phase should be a MESSAGE OUT phase so that we can send the + * IDENTIFY message. + * + * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG + * message (2 bytes) with a tag ID that we increment with every command + * until it wraps back to 0. + * + * XXX - it turns out that there are some broken SCSI-II devices, + * which claim to support tagged queuing but fail when more than + * some number of commands are issued at once. + */ + + /* Wait for start of REQ/ACK handshake */ + while (!(NCR5380_read(STATUS_REG) & SR_REQ)) + ; + + dprintk(NDEBUG_SELECTION, "scsi%d: target %d selected, going into MESSAGE OUT phase.\n", + HOSTNO, cmd->device->id); + tmp[0] = IDENTIFY(1, cmd->device->lun); + +#ifdef SUPPORT_TAGS + if (cmd->tag != TAG_NONE) { + tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG; + tmp[2] = cmd->tag; + len = 3; + } else + len = 1; +#else + len = 1; + cmd->tag = 0; +#endif /* SUPPORT_TAGS */ + + /* Send message(s) */ + data = tmp; + phase = PHASE_MSGOUT; + NCR5380_transfer_pio(instance, &phase, &len, &data); + dprintk(NDEBUG_SELECTION, "scsi%d: nexus established.\n", HOSTNO); + /* XXX need to handle errors here */ + hostdata->connected = cmd; +#ifndef SUPPORT_TAGS + hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); +#endif +#ifdef SUN3_SCSI_VME + dregs->csr |= CSR_INTR; +#endif + + initialize_SCp(cmd); + + return 0; +} + +/* + * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, + * unsigned char *phase, int *count, unsigned char **data) + * + * Purpose : transfers data in given phase using polled I/O + * + * Inputs : instance - instance of driver, *phase - pointer to + * what phase is expected, *count - pointer to number of + * bytes to transfer, **data - pointer to data pointer. + * + * Returns : -1 when different phase is entered without transferring + * maximum number of bytes, 0 if all bytes are transferred or exit + * is in same phase. + * + * Also, *phase, *count, *data are modified in place. + * + * XXX Note : handling for bus free may be useful. + */ + +/* + * Note : this code is not as quick as it could be, however it + * IS 100% reliable, and for the actual data transfer where speed + * counts, we will always do a pseudo DMA or DMA transfer. + */ + +static int NCR5380_transfer_pio(struct Scsi_Host *instance, + unsigned char *phase, int *count, + unsigned char **data) +{ + register unsigned char p = *phase, tmp; + register int c = *count; + register unsigned char *d = *data; + + /* + * The NCR5380 chip will only drive the SCSI bus when the + * phase specified in the appropriate bits of the TARGET COMMAND + * REGISTER match the STATUS REGISTER + */ + + NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); + + do { + /* + * Wait for assertion of REQ, after which the phase bits will be + * valid + */ + while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)) + ; + + dprintk(NDEBUG_HANDSHAKE, "scsi%d: REQ detected\n", HOSTNO); + + /* Check for phase mismatch */ + if ((tmp & PHASE_MASK) != p) { + dprintk(NDEBUG_PIO, "scsi%d: phase mismatch\n", HOSTNO); + NCR5380_dprint_phase(NDEBUG_PIO, instance); + break; + } + + /* Do actual transfer from SCSI bus to / from memory */ + if (!(p & SR_IO)) + NCR5380_write(OUTPUT_DATA_REG, *d); + else + *d = NCR5380_read(CURRENT_SCSI_DATA_REG); + + ++d; + + /* + * The SCSI standard suggests that in MSGOUT phase, the initiator + * should drop ATN on the last byte of the message phase + * after REQ has been asserted for the handshake but before + * the initiator raises ACK. + */ + + if (!(p & SR_IO)) { + if (!((p & SR_MSG) && c > 1)) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); + NCR5380_dprint(NDEBUG_PIO, instance); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_DATA | ICR_ASSERT_ACK); + } else { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_DATA | ICR_ASSERT_ATN); + NCR5380_dprint(NDEBUG_PIO, instance); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK); + } + } else { + NCR5380_dprint(NDEBUG_PIO, instance); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); + } + + while (NCR5380_read(STATUS_REG) & SR_REQ) + ; + + dprintk(NDEBUG_HANDSHAKE, "scsi%d: req false, handshake complete\n", HOSTNO); + + /* + * We have several special cases to consider during REQ/ACK handshaking : + * 1. We were in MSGOUT phase, and we are on the last byte of the + * message. ATN must be dropped as ACK is dropped. + * + * 2. We are in a MSGIN phase, and we are on the last byte of the + * message. We must exit with ACK asserted, so that the calling + * code may raise ATN before dropping ACK to reject the message. + * + * 3. ACK and ATN are clear and the target may proceed as normal. + */ + if (!(p == PHASE_MSGIN && c == 1)) { + if (p == PHASE_MSGOUT && c > 1) + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); + else + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + } + } while (--c); + + dprintk(NDEBUG_PIO, "scsi%d: residual %d\n", HOSTNO, c); + + *count = c; + *data = d; + tmp = NCR5380_read(STATUS_REG); + /* The phase read from the bus is valid if either REQ is (already) + * asserted or if ACK hasn't been released yet. The latter is the case if + * we're in MSGIN and all wanted bytes have been received. + */ + if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0)) + *phase = tmp & PHASE_MASK; + else + *phase = PHASE_UNKNOWN; + + if (!c || (*phase == p)) + return 0; + else + return -1; +} + +/* + * Function : do_abort (Scsi_Host *host) + * + * Purpose : abort the currently established nexus. Should only be + * called from a routine which can drop into a + * + * Returns : 0 on success, -1 on failure. + */ + +static int do_abort(struct Scsi_Host *instance) +{ + unsigned char tmp, *msgptr, phase; + int len; + + /* Request message out phase */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); + + /* + * Wait for the target to indicate a valid phase by asserting + * REQ. Once this happens, we'll have either a MSGOUT phase + * and can immediately send the ABORT message, or we'll have some + * other phase and will have to source/sink data. + * + * We really don't care what value was on the bus or what value + * the target sees, so we just handshake. + */ + + while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)) + ; + + NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); + + if ((tmp & PHASE_MASK) != PHASE_MSGOUT) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | + ICR_ASSERT_ACK); + while (NCR5380_read(STATUS_REG) & SR_REQ) + ; + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); + } + + tmp = ABORT; + msgptr = &tmp; + len = 1; + phase = PHASE_MSGOUT; + NCR5380_transfer_pio(instance, &phase, &len, &msgptr); + + /* + * If we got here, and the command completed successfully, + * we're about to go into bus free state. + */ + + return len ? -1 : 0; +} + +#if defined(REAL_DMA) +/* + * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, + * unsigned char *phase, int *count, unsigned char **data) + * + * Purpose : transfers data in given phase using either real + * or pseudo DMA. + * + * Inputs : instance - instance of driver, *phase - pointer to + * what phase is expected, *count - pointer to number of + * bytes to transfer, **data - pointer to data pointer. + * + * Returns : -1 when different phase is entered without transferring + * maximum number of bytes, 0 if all bytes or transferred or exit + * is in same phase. + * + * Also, *phase, *count, *data are modified in place. + * + */ + + +static int NCR5380_transfer_dma(struct Scsi_Host *instance, + unsigned char *phase, int *count, + unsigned char **data) +{ + SETUP_HOSTDATA(instance); + register int c = *count; + register unsigned char p = *phase; + unsigned long flags; + +#if defined(CONFIG_SUN3) + /* sanity check */ + if (!sun3_dma_setup_done) { + pr_err("scsi%d: transfer_dma without setup!\n", + instance->host_no); + BUG(); + } + hostdata->dma_len = c; + + dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n", + instance->host_no, (p & SR_IO) ? "reading" : "writing", + c, (p & SR_IO) ? "to" : "from", *data); + + /* netbsd turns off ints here, why not be safe and do it too */ + local_irq_save(flags); + + /* send start chain */ + sun3scsi_dma_start(c, *data); + + if (p & SR_IO) { + NCR5380_write(TARGET_COMMAND_REG, 1); + NCR5380_read(RESET_PARITY_INTERRUPT_REG); + NCR5380_write(INITIATOR_COMMAND_REG, 0); + NCR5380_write(MODE_REG, + (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR)); + NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); + } else { + NCR5380_write(TARGET_COMMAND_REG, 0); + NCR5380_read(RESET_PARITY_INTERRUPT_REG); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_DATA); + NCR5380_write(MODE_REG, + (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR)); + NCR5380_write(START_DMA_SEND_REG, 0); + } + +#ifdef SUN3_SCSI_VME + dregs->csr |= CSR_DMA_ENABLE; +#endif + + local_irq_restore(flags); + + sun3_dma_active = 1; + +#else /* !defined(CONFIG_SUN3) */ + register unsigned char *d = *data; + unsigned char tmp; + + if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) { + *phase = tmp; + return -1; + } + + if (hostdata->read_overruns && (p & SR_IO)) + c -= hostdata->read_overruns; + + dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n", + HOSTNO, (p & SR_IO) ? "reading" : "writing", + c, (p & SR_IO) ? "to" : "from", d); + + NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); + +#ifdef REAL_DMA + NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY); +#endif /* def REAL_DMA */ + + if (!(hostdata->flags & FLAG_LATE_DMA_SETUP)) { + /* On the Medusa, it is a must to initialize the DMA before + * starting the NCR. This is also the cleaner way for the TT. + */ + local_irq_save(flags); + hostdata->dma_len = (p & SR_IO) ? + NCR5380_dma_read_setup(instance, d, c) : + NCR5380_dma_write_setup(instance, d, c); + local_irq_restore(flags); + } + + if (p & SR_IO) + NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); + else { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); + NCR5380_write(START_DMA_SEND_REG, 0); + } + + if (hostdata->flags & FLAG_LATE_DMA_SETUP) { + /* On the Falcon, the DMA setup must be done after the last */ + /* NCR access, else the DMA setup gets trashed! + */ + local_irq_save(flags); + hostdata->dma_len = (p & SR_IO) ? + NCR5380_dma_read_setup(instance, d, c) : + NCR5380_dma_write_setup(instance, d, c); + local_irq_restore(flags); + } +#endif /* !defined(CONFIG_SUN3) */ + + return 0; +} +#endif /* defined(REAL_DMA) */ + +/* + * Function : NCR5380_information_transfer (struct Scsi_Host *instance) + * + * Purpose : run through the various SCSI phases and do as the target + * directs us to. Operates on the currently connected command, + * instance->connected. + * + * Inputs : instance, instance for which we are doing commands + * + * Side effects : SCSI things happen, the disconnected queue will be + * modified if a command disconnects, *instance->connected will + * change. + * + * XXX Note : we need to watch for bus free or a reset condition here + * to recover from an unexpected bus free condition. + */ + +static void NCR5380_information_transfer(struct Scsi_Host *instance) +{ + SETUP_HOSTDATA(instance); + unsigned long flags; + unsigned char msgout = NOP; + int sink = 0; + int len; +#if defined(REAL_DMA) + int transfersize; +#endif + unsigned char *data; + unsigned char phase, tmp, extended_msg[10], old_phase = 0xff; + struct scsi_cmnd *cmd = (struct scsi_cmnd *) hostdata->connected; + +#ifdef SUN3_SCSI_VME + dregs->csr |= CSR_INTR; +#endif + + while (1) { + tmp = NCR5380_read(STATUS_REG); + /* We only have a valid SCSI phase when REQ is asserted */ + if (tmp & SR_REQ) { + phase = (tmp & PHASE_MASK); + if (phase != old_phase) { + old_phase = phase; + NCR5380_dprint_phase(NDEBUG_INFORMATION, instance); + } +#if defined(CONFIG_SUN3) + if (phase == PHASE_CMDOUT) { +#if defined(REAL_DMA) + void *d; + unsigned long count; + + if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { + count = cmd->SCp.buffer->length; + d = sg_virt(cmd->SCp.buffer); + } else { + count = cmd->SCp.this_residual; + d = cmd->SCp.ptr; + } + /* this command setup for dma yet? */ + if ((count >= DMA_MIN_SIZE) && (sun3_dma_setup_done != cmd)) { + if (cmd->request->cmd_type == REQ_TYPE_FS) { + sun3scsi_dma_setup(d, count, + rq_data_dir(cmd->request)); + sun3_dma_setup_done = cmd; + } + } +#endif +#ifdef SUN3_SCSI_VME + dregs->csr |= CSR_INTR; +#endif + } +#endif /* CONFIG_SUN3 */ + + if (sink && (phase != PHASE_MSGOUT)) { + NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | + ICR_ASSERT_ACK); + while (NCR5380_read(STATUS_REG) & SR_REQ) + ; + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_ATN); + sink = 0; + continue; + } + + switch (phase) { + case PHASE_DATAOUT: +#if (NDEBUG & NDEBUG_NO_DATAOUT) + printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT " + "aborted\n", HOSTNO); + sink = 1; + do_abort(instance); + cmd->result = DID_ERROR << 16; + cmd->scsi_done(cmd); + return; +#endif + case PHASE_DATAIN: + /* + * If there is no room left in the current buffer in the + * scatter-gather list, move onto the next one. + */ + + if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { + ++cmd->SCp.buffer; + --cmd->SCp.buffers_residual; + cmd->SCp.this_residual = cmd->SCp.buffer->length; + cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); + /* ++roman: Try to merge some scatter-buffers if + * they are at contiguous physical addresses. + */ + merge_contiguous_buffers(cmd); + dprintk(NDEBUG_INFORMATION, "scsi%d: %d bytes and %d buffers left\n", + HOSTNO, cmd->SCp.this_residual, + cmd->SCp.buffers_residual); + } + + /* + * The preferred transfer method is going to be + * PSEUDO-DMA for systems that are strictly PIO, + * since we can let the hardware do the handshaking. + * + * For this to work, we need to know the transfersize + * ahead of time, since the pseudo-DMA code will sit + * in an unconditional loop. + */ + + /* ++roman: I suggest, this should be + * #if def(REAL_DMA) + * instead of leaving REAL_DMA out. + */ + +#if defined(REAL_DMA) + if ( +#if !defined(CONFIG_SUN3) + !cmd->device->borken && +#endif + (transfersize = NCR5380_dma_xfer_len(instance, cmd, phase)) >= DMA_MIN_SIZE) { + len = transfersize; + cmd->SCp.phase = phase; + if (NCR5380_transfer_dma(instance, &phase, + &len, (unsigned char **)&cmd->SCp.ptr)) { + /* + * If the watchdog timer fires, all future + * accesses to this device will use the + * polled-IO. */ + scmd_printk(KERN_INFO, cmd, + "switching to slow handshake\n"); + cmd->device->borken = 1; + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_ATN); + sink = 1; + do_abort(instance); + cmd->result = DID_ERROR << 16; + cmd->scsi_done(cmd); + /* XXX - need to source or sink data here, as appropriate */ + } else { +#ifdef REAL_DMA + /* ++roman: When using real DMA, + * information_transfer() should return after + * starting DMA since it has nothing more to + * do. + */ + return; +#else + cmd->SCp.this_residual -= transfersize - len; +#endif + } + } else +#endif /* defined(REAL_DMA) */ + NCR5380_transfer_pio(instance, &phase, + (int *)&cmd->SCp.this_residual, + (unsigned char **)&cmd->SCp.ptr); +#if defined(CONFIG_SUN3) && defined(REAL_DMA) + /* if we had intended to dma that command clear it */ + if (sun3_dma_setup_done == cmd) + sun3_dma_setup_done = NULL; +#endif + break; + case PHASE_MSGIN: + len = 1; + data = &tmp; + NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */ + NCR5380_transfer_pio(instance, &phase, &len, &data); + cmd->SCp.Message = tmp; + + switch (tmp) { + /* + * Linking lets us reduce the time required to get the + * next command out to the device, hopefully this will + * mean we don't waste another revolution due to the delays + * required by ARBITRATION and another SELECTION. + * + * In the current implementation proposal, low level drivers + * merely have to start the next command, pointed to by + * next_link, done() is called as with unlinked commands. + */ +#ifdef LINKED + case LINKED_CMD_COMPLETE: + case LINKED_FLG_CMD_COMPLETE: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + + dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked command " + "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun); + + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + /* + * Sanity check : A linked command should only terminate + * with one of these messages if there are more linked + * commands available. + */ + + if (!cmd->next_link) { + printk(KERN_NOTICE "scsi%d: target %d lun %llu " + "linked command complete, no next_link\n", + HOSTNO, cmd->device->id, cmd->device->lun); + sink = 1; + do_abort(instance); + return; + } + + initialize_SCp(cmd->next_link); + /* The next command is still part of this process; copy it + * and don't free it! */ + cmd->next_link->tag = cmd->tag; + cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); + dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked request " + "done, calling scsi_done().\n", + HOSTNO, cmd->device->id, cmd->device->lun); + cmd->scsi_done(cmd); + cmd = hostdata->connected; + break; +#endif /* def LINKED */ + case ABORT: + case COMMAND_COMPLETE: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d, lun %llu " + "completed\n", HOSTNO, cmd->device->id, cmd->device->lun); + + local_irq_save(flags); + hostdata->retain_dma_intr++; + hostdata->connected = NULL; +#ifdef SUPPORT_TAGS + cmd_free_tag(cmd); + if (status_byte(cmd->SCp.Status) == QUEUE_FULL) { + /* Turn a QUEUE FULL status into BUSY, I think the + * mid level cannot handle QUEUE FULL :-( (The + * command is retried after BUSY). Also update our + * queue size to the number of currently issued + * commands now. + */ + /* ++Andreas: the mid level code knows about + QUEUE_FULL now. */ + struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][cmd->device->lun]; + dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu returned " + "QUEUE_FULL after %d commands\n", + HOSTNO, cmd->device->id, cmd->device->lun, + ta->nr_allocated); + if (ta->queue_size > ta->nr_allocated) + ta->nr_allocated = ta->queue_size; + } +#else + hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); +#endif + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + + /* + * I'm not sure what the correct thing to do here is : + * + * If the command that just executed is NOT a request + * sense, the obvious thing to do is to set the result + * code to the values of the stored parameters. + * + * If it was a REQUEST SENSE command, we need some way to + * differentiate between the failure code of the original + * and the failure code of the REQUEST sense - the obvious + * case is success, where we fall through and leave the + * result code unchanged. + * + * The non-obvious place is where the REQUEST SENSE failed + */ + + if (cmd->cmnd[0] != REQUEST_SENSE) + cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); + else if (status_byte(cmd->SCp.Status) != GOOD) + cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16); + + if ((cmd->cmnd[0] == REQUEST_SENSE) && + hostdata->ses.cmd_len) { + scsi_eh_restore_cmnd(cmd, &hostdata->ses); + hostdata->ses.cmd_len = 0 ; + } + + if ((cmd->cmnd[0] != REQUEST_SENSE) && + (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) { + scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0); + + dprintk(NDEBUG_AUTOSENSE, "scsi%d: performing request sense\n", HOSTNO); + + LIST(cmd,hostdata->issue_queue); + SET_NEXT(cmd, hostdata->issue_queue); + hostdata->issue_queue = (struct scsi_cmnd *) cmd; + dprintk(NDEBUG_QUEUES, "scsi%d: REQUEST SENSE added to head of " + "issue queue\n", H_NO(cmd)); + } else { + cmd->scsi_done(cmd); + } + + local_irq_restore(flags); + + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + /* + * Restore phase bits to 0 so an interrupted selection, + * arbitration can resume. + */ + NCR5380_write(TARGET_COMMAND_REG, 0); + + while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) + barrier(); + + local_irq_save(flags); + hostdata->retain_dma_intr--; + /* ++roman: For Falcon SCSI, release the lock on the + * ST-DMA here if no other commands are waiting on the + * disconnected queue. + */ + maybe_release_dma_irq(instance); + local_irq_restore(flags); + return; + case MESSAGE_REJECT: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + switch (hostdata->last_message) { + case HEAD_OF_QUEUE_TAG: + case ORDERED_QUEUE_TAG: + case SIMPLE_QUEUE_TAG: + /* The target obviously doesn't support tagged + * queuing, even though it announced this ability in + * its INQUIRY data ?!? (maybe only this LUN?) Ok, + * clear 'tagged_supported' and lock the LUN, since + * the command is treated as untagged further on. + */ + cmd->device->tagged_supported = 0; + hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); + cmd->tag = TAG_NONE; + dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu rejected " + "QUEUE_TAG message; tagged queuing " + "disabled\n", + HOSTNO, cmd->device->id, cmd->device->lun); + break; + } + break; + case DISCONNECT: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + local_irq_save(flags); + cmd->device->disconnect = 1; + LIST(cmd,hostdata->disconnected_queue); + SET_NEXT(cmd, hostdata->disconnected_queue); + hostdata->connected = NULL; + hostdata->disconnected_queue = cmd; + local_irq_restore(flags); + dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d lun %llu was " + "moved from connected to the " + "disconnected_queue\n", HOSTNO, + cmd->device->id, cmd->device->lun); + /* + * Restore phase bits to 0 so an interrupted selection, + * arbitration can resume. + */ + NCR5380_write(TARGET_COMMAND_REG, 0); + + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + /* Wait for bus free to avoid nasty timeouts */ + while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) + barrier(); +#ifdef SUN3_SCSI_VME + dregs->csr |= CSR_DMA_ENABLE; +#endif + return; + /* + * The SCSI data pointer is *IMPLICITLY* saved on a disconnect + * operation, in violation of the SCSI spec so we can safely + * ignore SAVE/RESTORE pointers calls. + * + * Unfortunately, some disks violate the SCSI spec and + * don't issue the required SAVE_POINTERS message before + * disconnecting, and we have to break spec to remain + * compatible. + */ + case SAVE_POINTERS: + case RESTORE_POINTERS: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + break; + case EXTENDED_MESSAGE: + /* + * Extended messages are sent in the following format : + * Byte + * 0 EXTENDED_MESSAGE == 1 + * 1 length (includes one byte for code, doesn't + * include first two bytes) + * 2 code + * 3..length+1 arguments + * + * Start the extended message buffer with the EXTENDED_MESSAGE + * byte, since spi_print_msg() wants the whole thing. + */ + extended_msg[0] = EXTENDED_MESSAGE; + /* Accept first byte by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + + dprintk(NDEBUG_EXTENDED, "scsi%d: receiving extended message\n", HOSTNO); + + len = 2; + data = extended_msg + 1; + phase = PHASE_MSGIN; + NCR5380_transfer_pio(instance, &phase, &len, &data); + dprintk(NDEBUG_EXTENDED, "scsi%d: length=%d, code=0x%02x\n", HOSTNO, + (int)extended_msg[1], (int)extended_msg[2]); + + if (!len && extended_msg[1] <= + (sizeof(extended_msg) - 1)) { + /* Accept third byte by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + len = extended_msg[1] - 1; + data = extended_msg + 3; + phase = PHASE_MSGIN; + + NCR5380_transfer_pio(instance, &phase, &len, &data); + dprintk(NDEBUG_EXTENDED, "scsi%d: message received, residual %d\n", + HOSTNO, len); + + switch (extended_msg[2]) { + case EXTENDED_SDTR: + case EXTENDED_WDTR: + case EXTENDED_MODIFY_DATA_POINTER: + case EXTENDED_EXTENDED_IDENTIFY: + tmp = 0; + } + } else if (len) { + printk(KERN_NOTICE "scsi%d: error receiving " + "extended message\n", HOSTNO); + tmp = 0; + } else { + printk(KERN_NOTICE "scsi%d: extended message " + "code %02x length %d is too long\n", + HOSTNO, extended_msg[2], extended_msg[1]); + tmp = 0; + } + /* Fall through to reject message */ + + /* + * If we get something weird that we aren't expecting, + * reject it. + */ + default: + if (!tmp) { + printk(KERN_INFO "scsi%d: rejecting message ", + instance->host_no); + spi_print_msg(extended_msg); + printk("\n"); + } else if (tmp != EXTENDED_MESSAGE) + scmd_printk(KERN_INFO, cmd, + "rejecting unknown message %02x\n", + tmp); + else + scmd_printk(KERN_INFO, cmd, + "rejecting unknown extended message code %02x, length %d\n", + extended_msg[1], extended_msg[0]); + + msgout = MESSAGE_REJECT; + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); + break; + } /* switch (tmp) */ + break; + case PHASE_MSGOUT: + len = 1; + data = &msgout; + hostdata->last_message = msgout; + NCR5380_transfer_pio(instance, &phase, &len, &data); + if (msgout == ABORT) { + local_irq_save(flags); +#ifdef SUPPORT_TAGS + cmd_free_tag(cmd); +#else + hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); +#endif + hostdata->connected = NULL; + cmd->result = DID_ERROR << 16; + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + maybe_release_dma_irq(instance); + local_irq_restore(flags); + cmd->scsi_done(cmd); + return; + } + msgout = NOP; + break; + case PHASE_CMDOUT: + len = cmd->cmd_len; + data = cmd->cmnd; + /* + * XXX for performance reasons, on machines with a + * PSEUDO-DMA architecture we should probably + * use the dma transfer function. + */ + NCR5380_transfer_pio(instance, &phase, &len, &data); + break; + case PHASE_STATIN: + len = 1; + data = &tmp; + NCR5380_transfer_pio(instance, &phase, &len, &data); + cmd->SCp.Status = tmp; + break; + default: + printk("scsi%d: unknown phase\n", HOSTNO); + NCR5380_dprint(NDEBUG_ANY, instance); + } /* switch(phase) */ + } /* if (tmp * SR_REQ) */ + } /* while (1) */ +} + +/* + * Function : void NCR5380_reselect (struct Scsi_Host *instance) + * + * Purpose : does reselection, initializing the instance->connected + * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q + * nexus has been reestablished, + * + * Inputs : instance - this instance of the NCR5380. + * + */ + + +/* it might eventually prove necessary to do a dma setup on + reselection, but it doesn't seem to be needed now -- sam */ + +static void NCR5380_reselect(struct Scsi_Host *instance) +{ + SETUP_HOSTDATA(instance); + unsigned char target_mask; + unsigned char lun; +#ifdef SUPPORT_TAGS + unsigned char tag; +#endif + unsigned char msg[3]; + int __maybe_unused len; + unsigned char __maybe_unused *data, __maybe_unused phase; + struct scsi_cmnd *tmp = NULL, *prev; + + /* + * Disable arbitration, etc. since the host adapter obviously + * lost, and tell an interrupted NCR5380_select() to restart. + */ + + NCR5380_write(MODE_REG, MR_BASE); + hostdata->restart_select = 1; + + target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask); + + dprintk(NDEBUG_RESELECTION, "scsi%d: reselect\n", HOSTNO); + + /* + * At this point, we have detected that our SCSI ID is on the bus, + * SEL is true and BSY was false for at least one bus settle delay + * (400 ns). + * + * We must assert BSY ourselves, until the target drops the SEL + * signal. + */ + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY); + + while (NCR5380_read(STATUS_REG) & SR_SEL) + ; + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + + /* + * Wait for target to go into MSGIN. + */ + + while (!(NCR5380_read(STATUS_REG) & SR_REQ)) + ; + +#if defined(CONFIG_SUN3) && defined(REAL_DMA) + /* acknowledge toggle to MSGIN */ + NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN)); + + /* peek at the byte without really hitting the bus */ + msg[0] = NCR5380_read(CURRENT_SCSI_DATA_REG); +#else + len = 1; + data = msg; + phase = PHASE_MSGIN; + NCR5380_transfer_pio(instance, &phase, &len, &data); +#endif + + if (!(msg[0] & 0x80)) { + printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO); + spi_print_msg(msg); + do_abort(instance); + return; + } + lun = (msg[0] & 0x07); + +#if defined(SUPPORT_TAGS) && !defined(CONFIG_SUN3) + /* If the phase is still MSGIN, the target wants to send some more + * messages. In case it supports tagged queuing, this is probably a + * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus. + */ + tag = TAG_NONE; + if (phase == PHASE_MSGIN && (hostdata->flags & FLAG_TAGGED_QUEUING)) { + /* Accept previous IDENTIFY message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + len = 2; + data = msg + 1; + if (!NCR5380_transfer_pio(instance, &phase, &len, &data) && + msg[1] == SIMPLE_QUEUE_TAG) + tag = msg[2]; + dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at " + "reselection\n", HOSTNO, target_mask, lun, tag); + } +#endif + + /* + * Find the command corresponding to the I_T_L or I_T_L_Q nexus we + * just reestablished, and remove it from the disconnected queue. + */ + + for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue, prev = NULL; + tmp; prev = tmp, tmp = NEXT(tmp)) { + if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun) +#ifdef SUPPORT_TAGS + && (tag == tmp->tag) +#endif + ) { + if (prev) { + REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); + SET_NEXT(prev, NEXT(tmp)); + } else { + REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp)); + hostdata->disconnected_queue = NEXT(tmp); + } + SET_NEXT(tmp, NULL); + break; + } + } + + if (!tmp) { + printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d " +#ifdef SUPPORT_TAGS + "tag %d " +#endif + "not in disconnected_queue.\n", + HOSTNO, target_mask, lun +#ifdef SUPPORT_TAGS + , tag +#endif + ); + /* + * Since we have an established nexus that we can't do anything + * with, we must abort it. + */ + do_abort(instance); + return; + } + +#if defined(CONFIG_SUN3) && defined(REAL_DMA) + /* engage dma setup for the command we just saw */ + { + void *d; + unsigned long count; + + if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) { + count = tmp->SCp.buffer->length; + d = sg_virt(tmp->SCp.buffer); + } else { + count = tmp->SCp.this_residual; + d = tmp->SCp.ptr; + } + /* setup this command for dma if not already */ + if ((count >= DMA_MIN_SIZE) && (sun3_dma_setup_done != tmp)) { + sun3scsi_dma_setup(d, count, rq_data_dir(tmp->request)); + sun3_dma_setup_done = tmp; + } + } + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); +#endif + + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + +#if defined(SUPPORT_TAGS) && defined(CONFIG_SUN3) + /* If the phase is still MSGIN, the target wants to send some more + * messages. In case it supports tagged queuing, this is probably a + * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus. + */ + tag = TAG_NONE; + if (phase == PHASE_MSGIN && setup_use_tagged_queuing) { + /* Accept previous IDENTIFY message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + len = 2; + data = msg + 1; + if (!NCR5380_transfer_pio(instance, &phase, &len, &data) && + msg[1] == SIMPLE_QUEUE_TAG) + tag = msg[2]; + dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at reselection\n" + HOSTNO, target_mask, lun, tag); + } +#endif + + hostdata->connected = tmp; + dprintk(NDEBUG_RESELECTION, "scsi%d: nexus established, target = %d, lun = %llu, tag = %d\n", + HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag); +} + + +/* + * Function : int NCR5380_abort (struct scsi_cmnd *cmd) + * + * Purpose : abort a command + * + * Inputs : cmd - the scsi_cmnd to abort, code - code to set the + * host byte of the result field to, if zero DID_ABORTED is + * used. + * + * Returns : SUCCESS - success, FAILED on failure. + * + * XXX - there is no way to abort the command that is currently + * connected, you have to wait for it to complete. If this is + * a problem, we could implement longjmp() / setjmp(), setjmp() + * called where the loop started in NCR5380_main(). + */ + +static +int NCR5380_abort(struct scsi_cmnd *cmd) +{ + struct Scsi_Host *instance = cmd->device->host; + SETUP_HOSTDATA(instance); + struct scsi_cmnd *tmp, **prev; + unsigned long flags; + + scmd_printk(KERN_NOTICE, cmd, "aborting command\n"); + + NCR5380_print_status(instance); + + local_irq_save(flags); + + dprintk(NDEBUG_ABORT, "scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO, + NCR5380_read(BUS_AND_STATUS_REG), + NCR5380_read(STATUS_REG)); + +#if 1 + /* + * Case 1 : If the command is the currently executing command, + * we'll set the aborted flag and return control so that + * information transfer routine can exit cleanly. + */ + + if (hostdata->connected == cmd) { + + dprintk(NDEBUG_ABORT, "scsi%d: aborting connected command\n", HOSTNO); + /* + * We should perform BSY checking, and make sure we haven't slipped + * into BUS FREE. + */ + + /* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */ + /* + * Since we can't change phases until we've completed the current + * handshake, we have to source or sink a byte of data if the current + * phase is not MSGOUT. + */ + + /* + * Return control to the executing NCR drive so we can clear the + * aborted flag and get back into our main loop. + */ + + if (do_abort(instance) == 0) { + hostdata->aborted = 1; + hostdata->connected = NULL; + cmd->result = DID_ABORT << 16; +#ifdef SUPPORT_TAGS + cmd_free_tag(cmd); +#else + hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); +#endif + maybe_release_dma_irq(instance); + local_irq_restore(flags); + cmd->scsi_done(cmd); + return SUCCESS; + } else { + local_irq_restore(flags); + printk("scsi%d: abort of connected command failed!\n", HOSTNO); + return FAILED; + } + } +#endif + + /* + * Case 2 : If the command hasn't been issued yet, we simply remove it + * from the issue queue. + */ + for (prev = (struct scsi_cmnd **)&(hostdata->issue_queue), + tmp = (struct scsi_cmnd *)hostdata->issue_queue; + tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) { + if (cmd == tmp) { + REMOVE(5, *prev, tmp, NEXT(tmp)); + (*prev) = NEXT(tmp); + SET_NEXT(tmp, NULL); + tmp->result = DID_ABORT << 16; + maybe_release_dma_irq(instance); + local_irq_restore(flags); + dprintk(NDEBUG_ABORT, "scsi%d: abort removed command from issue queue.\n", + HOSTNO); + /* Tagged queuing note: no tag to free here, hasn't been assigned + * yet... */ + tmp->scsi_done(tmp); + return SUCCESS; + } + } + + /* + * Case 3 : If any commands are connected, we're going to fail the abort + * and let the high level SCSI driver retry at a later time or + * issue a reset. + * + * Timeouts, and therefore aborted commands, will be highly unlikely + * and handling them cleanly in this situation would make the common + * case of noresets less efficient, and would pollute our code. So, + * we fail. + */ + + if (hostdata->connected) { + local_irq_restore(flags); + dprintk(NDEBUG_ABORT, "scsi%d: abort failed, command connected.\n", HOSTNO); + return FAILED; + } + + /* + * Case 4: If the command is currently disconnected from the bus, and + * there are no connected commands, we reconnect the I_T_L or + * I_T_L_Q nexus associated with it, go into message out, and send + * an abort message. + * + * This case is especially ugly. In order to reestablish the nexus, we + * need to call NCR5380_select(). The easiest way to implement this + * function was to abort if the bus was busy, and let the interrupt + * handler triggered on the SEL for reselect take care of lost arbitrations + * where necessary, meaning interrupts need to be enabled. + * + * When interrupts are enabled, the queues may change - so we + * can't remove it from the disconnected queue before selecting it + * because that could cause a failure in hashing the nexus if that + * device reselected. + * + * Since the queues may change, we can't use the pointers from when we + * first locate it. + * + * So, we must first locate the command, and if NCR5380_select() + * succeeds, then issue the abort, relocate the command and remove + * it from the disconnected queue. + */ + + for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue; tmp; + tmp = NEXT(tmp)) { + if (cmd == tmp) { + local_irq_restore(flags); + dprintk(NDEBUG_ABORT, "scsi%d: aborting disconnected command.\n", HOSTNO); + + if (NCR5380_select(instance, cmd)) + return FAILED; + + dprintk(NDEBUG_ABORT, "scsi%d: nexus reestablished.\n", HOSTNO); + + do_abort(instance); + + local_irq_save(flags); + for (prev = (struct scsi_cmnd **)&(hostdata->disconnected_queue), + tmp = (struct scsi_cmnd *)hostdata->disconnected_queue; + tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) { + if (cmd == tmp) { + REMOVE(5, *prev, tmp, NEXT(tmp)); + *prev = NEXT(tmp); + SET_NEXT(tmp, NULL); + tmp->result = DID_ABORT << 16; + /* We must unlock the tag/LUN immediately here, since the + * target goes to BUS FREE and doesn't send us another + * message (COMMAND_COMPLETE or the like) + */ +#ifdef SUPPORT_TAGS + cmd_free_tag(tmp); +#else + hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); +#endif + maybe_release_dma_irq(instance); + local_irq_restore(flags); + tmp->scsi_done(tmp); + return SUCCESS; + } + } + } + } + + /* Maybe it is sufficient just to release the ST-DMA lock... (if + * possible at all) At least, we should check if the lock could be + * released after the abort, in case it is kept due to some bug. + */ + maybe_release_dma_irq(instance); + local_irq_restore(flags); + + /* + * Case 5 : If we reached this point, the command was not found in any of + * the queues. + * + * We probably reached this point because of an unlikely race condition + * between the command completing successfully and the abortion code, + * so we won't panic, but we will notify the user in case something really + * broke. + */ + + printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO); + + return FAILED; +} + + +/* + * Function : int NCR5380_reset (struct scsi_cmnd *cmd) + * + * Purpose : reset the SCSI bus. + * + * Returns : SUCCESS or FAILURE + * + */ + +static int NCR5380_bus_reset(struct scsi_cmnd *cmd) +{ + struct Scsi_Host *instance = cmd->device->host; + struct NCR5380_hostdata *hostdata = shost_priv(instance); + int i; + unsigned long flags; + + NCR5380_print_status(instance); + + /* get in phase */ + NCR5380_write(TARGET_COMMAND_REG, + PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG))); + /* assert RST */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST); + udelay(40); + /* reset NCR registers */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(TARGET_COMMAND_REG, 0); + NCR5380_write(SELECT_ENABLE_REG, 0); + /* ++roman: reset interrupt condition! otherwise no interrupts don't get + * through anymore ... */ + (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); + + /* After the reset, there are no more connected or disconnected commands + * and no busy units; so clear the low-level status here to avoid + * conflicts when the mid-level code tries to wake up the affected + * commands! + */ + + if (hostdata->issue_queue) + dprintk(NDEBUG_ABORT, "scsi%d: reset aborted issued command(s)\n", H_NO(cmd)); + if (hostdata->connected) + dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd)); + if (hostdata->disconnected_queue) + dprintk(NDEBUG_ABORT, "scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd)); + + local_irq_save(flags); + hostdata->issue_queue = NULL; + hostdata->connected = NULL; + hostdata->disconnected_queue = NULL; +#ifdef SUPPORT_TAGS + free_all_tags(hostdata); +#endif + for (i = 0; i < 8; ++i) + hostdata->busy[i] = 0; +#ifdef REAL_DMA + hostdata->dma_len = 0; +#endif + + maybe_release_dma_irq(instance); + local_irq_restore(flags); + + return SUCCESS; +} |