diff options
Diffstat (limited to 'kernel/arch/m68k/68360/commproc.c')
| -rw-r--r-- | kernel/arch/m68k/68360/commproc.c | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/kernel/arch/m68k/68360/commproc.c b/kernel/arch/m68k/68360/commproc.c new file mode 100644 index 000000000..14d7f35cd --- /dev/null +++ b/kernel/arch/m68k/68360/commproc.c @@ -0,0 +1,309 @@ +/* + * General Purpose functions for the global management of the + * Communication Processor Module. + * + * Copyright (c) 2000 Michael Leslie <mleslie@lineo.com> + * Copyright (c) 1997 Dan Malek (dmalek@jlc.net) + * + * In addition to the individual control of the communication + * channels, there are a few functions that globally affect the + * communication processor. + * + * Buffer descriptors must be allocated from the dual ported memory + * space. The allocator for that is here. When the communication + * process is reset, we reclaim the memory available. There is + * currently no deallocator for this memory. + * The amount of space available is platform dependent. On the + * MBX, the EPPC software loads additional microcode into the + * communication processor, and uses some of the DP ram for this + * purpose. Current, the first 512 bytes and the last 256 bytes of + * memory are used. Right now I am conservative and only use the + * memory that can never be used for microcode. If there are + * applications that require more DP ram, we can expand the boundaries + * but then we have to be careful of any downloaded microcode. + * + */ + +/* + * Michael Leslie <mleslie@lineo.com> + * adapted Dan Malek's ppc8xx drivers to M68360 + * + */ + +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/param.h> +#include <linux/string.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <asm/irq.h> +#include <asm/m68360.h> +#include <asm/commproc.h> + +/* #include <asm/page.h> */ +/* #include <asm/pgtable.h> */ +extern void *_quicc_base; +extern unsigned int system_clock; + + +static uint dp_alloc_base; /* Starting offset in DP ram */ +static uint dp_alloc_top; /* Max offset + 1 */ + +#if 0 +static void *host_buffer; /* One page of host buffer */ +static void *host_end; /* end + 1 */ +#endif + +/* struct cpm360_t *cpmp; */ /* Pointer to comm processor space */ + +QUICC *pquicc; +/* QUICC *quicc_dpram; */ /* mleslie - temporary; use extern pquicc elsewhere instead */ + + +/* CPM interrupt vector functions. */ +struct cpm_action { + irq_handler_t handler; + void *dev_id; +}; +static struct cpm_action cpm_vecs[CPMVEC_NR]; +static void cpm_interrupt(int irq, void * dev, struct pt_regs * regs); +static void cpm_error_interrupt(void *); + +/* prototypes: */ +void cpm_install_handler(int vec, irq_handler_t handler, void *dev_id); +void m360_cpm_reset(void); + + + + +void __init m360_cpm_reset() +{ +/* pte_t *pte; */ + + pquicc = (struct quicc *)(_quicc_base); /* initialized in crt0_rXm.S */ + + /* Perform a CPM reset. */ + pquicc->cp_cr = (SOFTWARE_RESET | CMD_FLAG); + + /* Wait for CPM to become ready (should be 2 clocks). */ + while (pquicc->cp_cr & CMD_FLAG); + + /* On the recommendation of the 68360 manual, p. 7-60 + * - Set sdma interrupt service mask to 7 + * - Set sdma arbitration ID to 4 + */ + pquicc->sdma_sdcr = 0x0740; + + + /* Claim the DP memory for our use. + */ + dp_alloc_base = CPM_DATAONLY_BASE; + dp_alloc_top = dp_alloc_base + CPM_DATAONLY_SIZE; + + + /* Set the host page for allocation. + */ + /* host_buffer = host_page_addr; */ + /* host_end = host_page_addr + PAGE_SIZE; */ + + /* pte = find_pte(&init_mm, host_page_addr); */ + /* pte_val(*pte) |= _PAGE_NO_CACHE; */ + /* flush_tlb_page(current->mm->mmap, host_buffer); */ + + /* Tell everyone where the comm processor resides. + */ +/* cpmp = (cpm360_t *)commproc; */ +} + + +/* This is called during init_IRQ. We used to do it above, but this + * was too early since init_IRQ was not yet called. + */ +void +cpm_interrupt_init(void) +{ + /* Initialize the CPM interrupt controller. + * NOTE THAT pquicc had better have been initialized! + * reference: MC68360UM p. 7-377 + */ + pquicc->intr_cicr = + (CICR_SCD_SCC4 | CICR_SCC_SCC3 | CICR_SCB_SCC2 | CICR_SCA_SCC1) | + (CPM_INTERRUPT << 13) | + CICR_HP_MASK | + (CPM_VECTOR_BASE << 5) | + CICR_SPS; + + /* mask all CPM interrupts from reaching the cpu32 core: */ + pquicc->intr_cimr = 0; + + + /* mles - If I understand correctly, the 360 just pops over to the CPM + * specific vector, obviating the necessity to vector through the IRQ + * whose priority the CPM is set to. This needs a closer look, though. + */ + + /* Set our interrupt handler with the core CPU. */ +/* if (request_irq(CPM_INTERRUPT, cpm_interrupt, 0, "cpm", NULL) != 0) */ +/* panic("Could not allocate CPM IRQ!"); */ + + /* Install our own error handler. + */ + /* I think we want to hold off on this one for the moment - mles */ + /* cpm_install_handler(CPMVEC_ERROR, cpm_error_interrupt, NULL); */ + + /* master CPM interrupt enable */ + /* pquicc->intr_cicr |= CICR_IEN; */ /* no such animal for 360 */ +} + + + +/* CPM interrupt controller interrupt. +*/ +static void +cpm_interrupt(int irq, void * dev, struct pt_regs * regs) +{ + /* uint vec; */ + + /* mles: Note that this stuff is currently being performed by + * M68360_do_irq(int vec, struct pt_regs *fp), in ../ints.c */ + + /* figure out the vector */ + /* call that vector's handler */ + /* clear the irq's bit in the service register */ + +#if 0 /* old 860 stuff: */ + /* Get the vector by setting the ACK bit and then reading + * the register. + */ + ((volatile immap_t *)IMAP_ADDR)->im_cpic.cpic_civr = 1; + vec = ((volatile immap_t *)IMAP_ADDR)->im_cpic.cpic_civr; + vec >>= 11; + + + if (cpm_vecs[vec].handler != 0) + (*cpm_vecs[vec].handler)(cpm_vecs[vec].dev_id); + else + ((immap_t *)IMAP_ADDR)->im_cpic.cpic_cimr &= ~(1 << vec); + + /* After servicing the interrupt, we have to remove the status + * indicator. + */ + ((immap_t *)IMAP_ADDR)->im_cpic.cpic_cisr |= (1 << vec); +#endif + +} + +/* The CPM can generate the error interrupt when there is a race condition + * between generating and masking interrupts. All we have to do is ACK it + * and return. This is a no-op function so we don't need any special + * tests in the interrupt handler. + */ +static void +cpm_error_interrupt(void *dev) +{ +} + +/* Install a CPM interrupt handler. +*/ +void +cpm_install_handler(int vec, irq_handler_t handler, void *dev_id) +{ + + request_irq(vec, handler, 0, "timer", dev_id); + +/* if (cpm_vecs[vec].handler != 0) */ +/* printk(KERN_INFO "CPM interrupt %x replacing %x\n", */ +/* (uint)handler, (uint)cpm_vecs[vec].handler); */ +/* cpm_vecs[vec].handler = handler; */ +/* cpm_vecs[vec].dev_id = dev_id; */ + + /* ((immap_t *)IMAP_ADDR)->im_cpic.cpic_cimr |= (1 << vec); */ +/* pquicc->intr_cimr |= (1 << vec); */ + +} + +/* Free a CPM interrupt handler. +*/ +void +cpm_free_handler(int vec) +{ + cpm_vecs[vec].handler = NULL; + cpm_vecs[vec].dev_id = NULL; + /* ((immap_t *)IMAP_ADDR)->im_cpic.cpic_cimr &= ~(1 << vec); */ + pquicc->intr_cimr &= ~(1 << vec); +} + + + + +/* Allocate some memory from the dual ported ram. We may want to + * enforce alignment restrictions, but right now everyone is a good + * citizen. + */ +uint +m360_cpm_dpalloc(uint size) +{ + uint retloc; + + if ((dp_alloc_base + size) >= dp_alloc_top) + return(CPM_DP_NOSPACE); + + retloc = dp_alloc_base; + dp_alloc_base += size; + + return(retloc); +} + + +#if 0 /* mleslie - for now these are simply kmalloc'd */ +/* We also own one page of host buffer space for the allocation of + * UART "fifos" and the like. + */ +uint +m360_cpm_hostalloc(uint size) +{ + uint retloc; + + if ((host_buffer + size) >= host_end) + return(0); + + retloc = host_buffer; + host_buffer += size; + + return(retloc); +} +#endif + + +/* Set a baud rate generator. This needs lots of work. There are + * four BRGs, any of which can be wired to any channel. + * The internal baud rate clock is the system clock divided by 16. + * This assumes the baudrate is 16x oversampled by the uart. + */ +/* #define BRG_INT_CLK (((bd_t *)__res)->bi_intfreq * 1000000) */ +#define BRG_INT_CLK system_clock +#define BRG_UART_CLK (BRG_INT_CLK/16) + +void +m360_cpm_setbrg(uint brg, uint rate) +{ + volatile uint *bp; + + /* This is good enough to get SMCs running..... + */ + /* bp = (uint *)&cpmp->cp_brgc1; */ + bp = (volatile uint *)(&pquicc->brgc[0].l); + bp += brg; + *bp = ((BRG_UART_CLK / rate - 1) << 1) | CPM_BRG_EN; +} + + +/* + * Local variables: + * c-indent-level: 4 + * c-basic-offset: 4 + * tab-width: 4 + * End: + */ |