linux/arch/m68knommu/platform/68360/commproc.c

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/*
* 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/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 {
void (*handler)(void *);
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, void (*handler)(), void *dev_id);
void m360_cpm_reset(void);
void 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, void (*handler)(), void *dev_id)
{
request_irq(vec, handler, IRQ_FLG_LOCK, "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:
*/