diff options
Diffstat (limited to 'qemu/hw/dma/i8257.c')
| -rw-r--r-- | qemu/hw/dma/i8257.c | 598 |
1 files changed, 598 insertions, 0 deletions
diff --git a/qemu/hw/dma/i8257.c b/qemu/hw/dma/i8257.c new file mode 100644 index 000000000..a414029be --- /dev/null +++ b/qemu/hw/dma/i8257.c @@ -0,0 +1,598 @@ +/* + * QEMU DMA emulation + * + * Copyright (c) 2003-2004 Vassili Karpov (malc) + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#include "hw/hw.h" +#include "hw/isa/isa.h" +#include "qemu/main-loop.h" +#include "trace.h" + +/* #define DEBUG_DMA */ + +#define dolog(...) fprintf (stderr, "dma: " __VA_ARGS__) +#ifdef DEBUG_DMA +#define linfo(...) fprintf (stderr, "dma: " __VA_ARGS__) +#define ldebug(...) fprintf (stderr, "dma: " __VA_ARGS__) +#else +#define linfo(...) +#define ldebug(...) +#endif + +struct dma_regs { + int now[2]; + uint16_t base[2]; + uint8_t mode; + uint8_t page; + uint8_t pageh; + uint8_t dack; + uint8_t eop; + DMA_transfer_handler transfer_handler; + void *opaque; +}; + +#define ADDR 0 +#define COUNT 1 + +static struct dma_cont { + uint8_t status; + uint8_t command; + uint8_t mask; + uint8_t flip_flop; + int dshift; + struct dma_regs regs[4]; + qemu_irq *cpu_request_exit; + MemoryRegion channel_io; + MemoryRegion cont_io; +} dma_controllers[2]; + +enum { + CMD_MEMORY_TO_MEMORY = 0x01, + CMD_FIXED_ADDRESS = 0x02, + CMD_BLOCK_CONTROLLER = 0x04, + CMD_COMPRESSED_TIME = 0x08, + CMD_CYCLIC_PRIORITY = 0x10, + CMD_EXTENDED_WRITE = 0x20, + CMD_LOW_DREQ = 0x40, + CMD_LOW_DACK = 0x80, + CMD_NOT_SUPPORTED = CMD_MEMORY_TO_MEMORY | CMD_FIXED_ADDRESS + | CMD_COMPRESSED_TIME | CMD_CYCLIC_PRIORITY | CMD_EXTENDED_WRITE + | CMD_LOW_DREQ | CMD_LOW_DACK + +}; + +static void DMA_run (void); + +static int channels[8] = {-1, 2, 3, 1, -1, -1, -1, 0}; + +static void write_page (void *opaque, uint32_t nport, uint32_t data) +{ + struct dma_cont *d = opaque; + int ichan; + + ichan = channels[nport & 7]; + if (-1 == ichan) { + dolog ("invalid channel %#x %#x\n", nport, data); + return; + } + d->regs[ichan].page = data; +} + +static void write_pageh (void *opaque, uint32_t nport, uint32_t data) +{ + struct dma_cont *d = opaque; + int ichan; + + ichan = channels[nport & 7]; + if (-1 == ichan) { + dolog ("invalid channel %#x %#x\n", nport, data); + return; + } + d->regs[ichan].pageh = data; +} + +static uint32_t read_page (void *opaque, uint32_t nport) +{ + struct dma_cont *d = opaque; + int ichan; + + ichan = channels[nport & 7]; + if (-1 == ichan) { + dolog ("invalid channel read %#x\n", nport); + return 0; + } + return d->regs[ichan].page; +} + +static uint32_t read_pageh (void *opaque, uint32_t nport) +{ + struct dma_cont *d = opaque; + int ichan; + + ichan = channels[nport & 7]; + if (-1 == ichan) { + dolog ("invalid channel read %#x\n", nport); + return 0; + } + return d->regs[ichan].pageh; +} + +static inline void init_chan (struct dma_cont *d, int ichan) +{ + struct dma_regs *r; + + r = d->regs + ichan; + r->now[ADDR] = r->base[ADDR] << d->dshift; + r->now[COUNT] = 0; +} + +static inline int getff (struct dma_cont *d) +{ + int ff; + + ff = d->flip_flop; + d->flip_flop = !ff; + return ff; +} + +static uint64_t read_chan(void *opaque, hwaddr nport, unsigned size) +{ + struct dma_cont *d = opaque; + int ichan, nreg, iport, ff, val, dir; + struct dma_regs *r; + + iport = (nport >> d->dshift) & 0x0f; + ichan = iport >> 1; + nreg = iport & 1; + r = d->regs + ichan; + + dir = ((r->mode >> 5) & 1) ? -1 : 1; + ff = getff (d); + if (nreg) + val = (r->base[COUNT] << d->dshift) - r->now[COUNT]; + else + val = r->now[ADDR] + r->now[COUNT] * dir; + + ldebug ("read_chan %#x -> %d\n", iport, val); + return (val >> (d->dshift + (ff << 3))) & 0xff; +} + +static void write_chan(void *opaque, hwaddr nport, uint64_t data, + unsigned size) +{ + struct dma_cont *d = opaque; + int iport, ichan, nreg; + struct dma_regs *r; + + iport = (nport >> d->dshift) & 0x0f; + ichan = iport >> 1; + nreg = iport & 1; + r = d->regs + ichan; + if (getff (d)) { + r->base[nreg] = (r->base[nreg] & 0xff) | ((data << 8) & 0xff00); + init_chan (d, ichan); + } else { + r->base[nreg] = (r->base[nreg] & 0xff00) | (data & 0xff); + } +} + +static void write_cont(void *opaque, hwaddr nport, uint64_t data, + unsigned size) +{ + struct dma_cont *d = opaque; + int iport, ichan = 0; + + iport = (nport >> d->dshift) & 0x0f; + switch (iport) { + case 0x00: /* command */ + if ((data != 0) && (data & CMD_NOT_SUPPORTED)) { + dolog("command %"PRIx64" not supported\n", data); + return; + } + d->command = data; + break; + + case 0x01: + ichan = data & 3; + if (data & 4) { + d->status |= 1 << (ichan + 4); + } + else { + d->status &= ~(1 << (ichan + 4)); + } + d->status &= ~(1 << ichan); + DMA_run(); + break; + + case 0x02: /* single mask */ + if (data & 4) + d->mask |= 1 << (data & 3); + else + d->mask &= ~(1 << (data & 3)); + DMA_run(); + break; + + case 0x03: /* mode */ + { + ichan = data & 3; +#ifdef DEBUG_DMA + { + int op, ai, dir, opmode; + op = (data >> 2) & 3; + ai = (data >> 4) & 1; + dir = (data >> 5) & 1; + opmode = (data >> 6) & 3; + + linfo ("ichan %d, op %d, ai %d, dir %d, opmode %d\n", + ichan, op, ai, dir, opmode); + } +#endif + d->regs[ichan].mode = data; + break; + } + + case 0x04: /* clear flip flop */ + d->flip_flop = 0; + break; + + case 0x05: /* reset */ + d->flip_flop = 0; + d->mask = ~0; + d->status = 0; + d->command = 0; + break; + + case 0x06: /* clear mask for all channels */ + d->mask = 0; + DMA_run(); + break; + + case 0x07: /* write mask for all channels */ + d->mask = data; + DMA_run(); + break; + + default: + dolog ("unknown iport %#x\n", iport); + break; + } + +#ifdef DEBUG_DMA + if (0xc != iport) { + linfo ("write_cont: nport %#06x, ichan % 2d, val %#06x\n", + nport, ichan, data); + } +#endif +} + +static uint64_t read_cont(void *opaque, hwaddr nport, unsigned size) +{ + struct dma_cont *d = opaque; + int iport, val; + + iport = (nport >> d->dshift) & 0x0f; + switch (iport) { + case 0x00: /* status */ + val = d->status; + d->status &= 0xf0; + break; + case 0x01: /* mask */ + val = d->mask; + break; + default: + val = 0; + break; + } + + ldebug ("read_cont: nport %#06x, iport %#04x val %#x\n", nport, iport, val); + return val; +} + +int DMA_get_channel_mode (int nchan) +{ + return dma_controllers[nchan > 3].regs[nchan & 3].mode; +} + +void DMA_hold_DREQ (int nchan) +{ + int ncont, ichan; + + ncont = nchan > 3; + ichan = nchan & 3; + linfo ("held cont=%d chan=%d\n", ncont, ichan); + dma_controllers[ncont].status |= 1 << (ichan + 4); + DMA_run(); +} + +void DMA_release_DREQ (int nchan) +{ + int ncont, ichan; + + ncont = nchan > 3; + ichan = nchan & 3; + linfo ("released cont=%d chan=%d\n", ncont, ichan); + dma_controllers[ncont].status &= ~(1 << (ichan + 4)); + DMA_run(); +} + +static void channel_run (int ncont, int ichan) +{ + int n; + struct dma_regs *r = &dma_controllers[ncont].regs[ichan]; +#ifdef DEBUG_DMA + int dir, opmode; + + dir = (r->mode >> 5) & 1; + opmode = (r->mode >> 6) & 3; + + if (dir) { + dolog ("DMA in address decrement mode\n"); + } + if (opmode != 1) { + dolog ("DMA not in single mode select %#x\n", opmode); + } +#endif + + n = r->transfer_handler (r->opaque, ichan + (ncont << 2), + r->now[COUNT], (r->base[COUNT] + 1) << ncont); + r->now[COUNT] = n; + ldebug ("dma_pos %d size %d\n", n, (r->base[COUNT] + 1) << ncont); +} + +static QEMUBH *dma_bh; + +static void DMA_run (void) +{ + struct dma_cont *d; + int icont, ichan; + int rearm = 0; + static int running = 0; + + if (running) { + rearm = 1; + goto out; + } else { + running = 1; + } + + d = dma_controllers; + + for (icont = 0; icont < 2; icont++, d++) { + for (ichan = 0; ichan < 4; ichan++) { + int mask; + + mask = 1 << ichan; + + if ((0 == (d->mask & mask)) && (0 != (d->status & (mask << 4)))) { + channel_run (icont, ichan); + rearm = 1; + } + } + } + + running = 0; +out: + if (rearm) + qemu_bh_schedule_idle(dma_bh); +} + +static void DMA_run_bh(void *unused) +{ + DMA_run(); +} + +void DMA_register_channel (int nchan, + DMA_transfer_handler transfer_handler, + void *opaque) +{ + struct dma_regs *r; + int ichan, ncont; + + ncont = nchan > 3; + ichan = nchan & 3; + + r = dma_controllers[ncont].regs + ichan; + r->transfer_handler = transfer_handler; + r->opaque = opaque; +} + +int DMA_read_memory (int nchan, void *buf, int pos, int len) +{ + struct dma_regs *r = &dma_controllers[nchan > 3].regs[nchan & 3]; + hwaddr addr = ((r->pageh & 0x7f) << 24) | (r->page << 16) | r->now[ADDR]; + + if (r->mode & 0x20) { + int i; + uint8_t *p = buf; + + cpu_physical_memory_read (addr - pos - len, buf, len); + /* What about 16bit transfers? */ + for (i = 0; i < len >> 1; i++) { + uint8_t b = p[len - i - 1]; + p[i] = b; + } + } + else + cpu_physical_memory_read (addr + pos, buf, len); + + return len; +} + +int DMA_write_memory (int nchan, void *buf, int pos, int len) +{ + struct dma_regs *r = &dma_controllers[nchan > 3].regs[nchan & 3]; + hwaddr addr = ((r->pageh & 0x7f) << 24) | (r->page << 16) | r->now[ADDR]; + + if (r->mode & 0x20) { + int i; + uint8_t *p = buf; + + cpu_physical_memory_write (addr - pos - len, buf, len); + /* What about 16bit transfers? */ + for (i = 0; i < len; i++) { + uint8_t b = p[len - i - 1]; + p[i] = b; + } + } + else + cpu_physical_memory_write (addr + pos, buf, len); + + return len; +} + +/* request the emulator to transfer a new DMA memory block ASAP */ +void DMA_schedule(int nchan) +{ + struct dma_cont *d = &dma_controllers[nchan > 3]; + + qemu_irq_pulse(*d->cpu_request_exit); +} + +static void dma_reset(void *opaque) +{ + struct dma_cont *d = opaque; + write_cont(d, (0x05 << d->dshift), 0, 1); +} + +static int dma_phony_handler (void *opaque, int nchan, int dma_pos, int dma_len) +{ + trace_i8257_unregistered_dma(nchan, dma_pos, dma_len); + return dma_pos; +} + + +static const MemoryRegionOps channel_io_ops = { + .read = read_chan, + .write = write_chan, + .endianness = DEVICE_NATIVE_ENDIAN, + .impl = { + .min_access_size = 1, + .max_access_size = 1, + }, +}; + +/* IOport from page_base */ +static const MemoryRegionPortio page_portio_list[] = { + { 0x01, 3, 1, .write = write_page, .read = read_page, }, + { 0x07, 1, 1, .write = write_page, .read = read_page, }, + PORTIO_END_OF_LIST(), +}; + +/* IOport from pageh_base */ +static const MemoryRegionPortio pageh_portio_list[] = { + { 0x01, 3, 1, .write = write_pageh, .read = read_pageh, }, + { 0x07, 3, 1, .write = write_pageh, .read = read_pageh, }, + PORTIO_END_OF_LIST(), +}; + +static const MemoryRegionOps cont_io_ops = { + .read = read_cont, + .write = write_cont, + .endianness = DEVICE_NATIVE_ENDIAN, + .impl = { + .min_access_size = 1, + .max_access_size = 1, + }, +}; + +/* dshift = 0: 8 bit DMA, 1 = 16 bit DMA */ +static void dma_init2(struct dma_cont *d, int base, int dshift, + int page_base, int pageh_base, + qemu_irq *cpu_request_exit) +{ + int i; + + d->dshift = dshift; + d->cpu_request_exit = cpu_request_exit; + + memory_region_init_io(&d->channel_io, NULL, &channel_io_ops, d, + "dma-chan", 8 << d->dshift); + memory_region_add_subregion(isa_address_space_io(NULL), + base, &d->channel_io); + + isa_register_portio_list(NULL, page_base, page_portio_list, d, + "dma-page"); + if (pageh_base >= 0) { + isa_register_portio_list(NULL, pageh_base, pageh_portio_list, d, + "dma-pageh"); + } + + memory_region_init_io(&d->cont_io, NULL, &cont_io_ops, d, "dma-cont", + 8 << d->dshift); + memory_region_add_subregion(isa_address_space_io(NULL), + base + (8 << d->dshift), &d->cont_io); + + qemu_register_reset(dma_reset, d); + dma_reset(d); + for (i = 0; i < ARRAY_SIZE (d->regs); ++i) { + d->regs[i].transfer_handler = dma_phony_handler; + } +} + +static const VMStateDescription vmstate_dma_regs = { + .name = "dma_regs", + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_INT32_ARRAY(now, struct dma_regs, 2), + VMSTATE_UINT16_ARRAY(base, struct dma_regs, 2), + VMSTATE_UINT8(mode, struct dma_regs), + VMSTATE_UINT8(page, struct dma_regs), + VMSTATE_UINT8(pageh, struct dma_regs), + VMSTATE_UINT8(dack, struct dma_regs), + VMSTATE_UINT8(eop, struct dma_regs), + VMSTATE_END_OF_LIST() + } +}; + +static int dma_post_load(void *opaque, int version_id) +{ + DMA_run(); + + return 0; +} + +static const VMStateDescription vmstate_dma = { + .name = "dma", + .version_id = 1, + .minimum_version_id = 1, + .post_load = dma_post_load, + .fields = (VMStateField[]) { + VMSTATE_UINT8(command, struct dma_cont), + VMSTATE_UINT8(mask, struct dma_cont), + VMSTATE_UINT8(flip_flop, struct dma_cont), + VMSTATE_INT32(dshift, struct dma_cont), + VMSTATE_STRUCT_ARRAY(regs, struct dma_cont, 4, 1, vmstate_dma_regs, struct dma_regs), + VMSTATE_END_OF_LIST() + } +}; + +void DMA_init(int high_page_enable, qemu_irq *cpu_request_exit) +{ + dma_init2(&dma_controllers[0], 0x00, 0, 0x80, + high_page_enable ? 0x480 : -1, cpu_request_exit); + dma_init2(&dma_controllers[1], 0xc0, 1, 0x88, + high_page_enable ? 0x488 : -1, cpu_request_exit); + vmstate_register (NULL, 0, &vmstate_dma, &dma_controllers[0]); + vmstate_register (NULL, 1, &vmstate_dma, &dma_controllers[1]); + + dma_bh = qemu_bh_new(DMA_run_bh, NULL); +} |