linux/arch/ppc/syslib/cpm2_common.c

198 lines
4.9 KiB
C

/*
* General Purpose functions for the global management of the
* 8260 Communication Processor Module.
* Copyright (c) 1999 Dan Malek (dmalek@jlc.net)
* Copyright (c) 2000 MontaVista Software, Inc (source@mvista.com)
* 2.3.99 Updates
*
* 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.
*/
#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 <linux/module.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/mpc8260.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/cpm2.h>
#include <asm/rheap.h>
static void cpm2_dpinit(void);
cpm_cpm2_t *cpmp; /* Pointer to comm processor space */
/* We allocate this here because it is used almost exclusively for
* the communication processor devices.
*/
cpm2_map_t *cpm2_immr;
#define CPM_MAP_SIZE (0x40000) /* 256k - the PQ3 reserve this amount
of space for CPM as it is larger
than on PQ2 */
void
cpm2_reset(void)
{
cpm2_immr = (cpm2_map_t *)ioremap(CPM_MAP_ADDR, CPM_MAP_SIZE);
/* Reclaim the DP memory for our use.
*/
cpm2_dpinit();
/* Tell everyone where the comm processor resides.
*/
cpmp = &cpm2_immr->im_cpm;
}
/* Set a baud rate generator. This needs lots of work. There are
* eight BRGs, which can be connected to the CPM channels or output
* as clocks. The BRGs are in two different block of internal
* memory mapped space.
* The baud rate clock is the system clock divided by something.
* It was set up long ago during the initial boot phase and is
* is given to us.
* Baud rate clocks are zero-based in the driver code (as that maps
* to port numbers). Documentation uses 1-based numbering.
*/
#define BRG_INT_CLK (((bd_t *)__res)->bi_brgfreq)
#define BRG_UART_CLK (BRG_INT_CLK/16)
/* This function is used by UARTS, or anything else that uses a 16x
* oversampled clock.
*/
void
cpm_setbrg(uint brg, uint rate)
{
volatile uint *bp;
/* This is good enough to get SMCs running.....
*/
if (brg < 4) {
bp = (uint *)&cpm2_immr->im_brgc1;
}
else {
bp = (uint *)&cpm2_immr->im_brgc5;
brg -= 4;
}
bp += brg;
*bp = ((BRG_UART_CLK / rate) << 1) | CPM_BRG_EN;
}
/* This function is used to set high speed synchronous baud rate
* clocks.
*/
void
cpm2_fastbrg(uint brg, uint rate, int div16)
{
volatile uint *bp;
if (brg < 4) {
bp = (uint *)&cpm2_immr->im_brgc1;
}
else {
bp = (uint *)&cpm2_immr->im_brgc5;
brg -= 4;
}
bp += brg;
*bp = ((BRG_INT_CLK / rate) << 1) | CPM_BRG_EN;
if (div16)
*bp |= CPM_BRG_DIV16;
}
/*
* dpalloc / dpfree bits.
*/
static spinlock_t cpm_dpmem_lock;
/* 16 blocks should be enough to satisfy all requests
* until the memory subsystem goes up... */
static rh_block_t cpm_boot_dpmem_rh_block[16];
static rh_info_t cpm_dpmem_info;
static void cpm2_dpinit(void)
{
spin_lock_init(&cpm_dpmem_lock);
/* initialize the info header */
rh_init(&cpm_dpmem_info, 1,
sizeof(cpm_boot_dpmem_rh_block) /
sizeof(cpm_boot_dpmem_rh_block[0]),
cpm_boot_dpmem_rh_block);
/* Attach the usable dpmem area */
/* XXX: This is actually crap. CPM_DATAONLY_BASE and
* CPM_DATAONLY_SIZE is only a subset of the available dpram. It
* varies with the processor and the microcode patches activated.
* But the following should be at least safe.
*/
rh_attach_region(&cpm_dpmem_info, (void *)CPM_DATAONLY_BASE,
CPM_DATAONLY_SIZE);
}
/* This function returns an index into the DPRAM area.
*/
uint cpm_dpalloc(uint size, uint align)
{
void *start;
unsigned long flags;
spin_lock_irqsave(&cpm_dpmem_lock, flags);
cpm_dpmem_info.alignment = align;
start = rh_alloc(&cpm_dpmem_info, size, "commproc");
spin_unlock_irqrestore(&cpm_dpmem_lock, flags);
return (uint)start;
}
EXPORT_SYMBOL(cpm_dpalloc);
int cpm_dpfree(uint offset)
{
int ret;
unsigned long flags;
spin_lock_irqsave(&cpm_dpmem_lock, flags);
ret = rh_free(&cpm_dpmem_info, (void *)offset);
spin_unlock_irqrestore(&cpm_dpmem_lock, flags);
return ret;
}
EXPORT_SYMBOL(cpm_dpfree);
/* not sure if this is ever needed */
uint cpm_dpalloc_fixed(uint offset, uint size, uint align)
{
void *start;
unsigned long flags;
spin_lock_irqsave(&cpm_dpmem_lock, flags);
cpm_dpmem_info.alignment = align;
start = rh_alloc_fixed(&cpm_dpmem_info, (void *)offset, size, "commproc");
spin_unlock_irqrestore(&cpm_dpmem_lock, flags);
return (uint)start;
}
EXPORT_SYMBOL(cpm_dpalloc_fixed);
void cpm_dpdump(void)
{
rh_dump(&cpm_dpmem_info);
}
EXPORT_SYMBOL(cpm_dpdump);
void *cpm_dpram_addr(uint offset)
{
return (void *)&cpm2_immr->im_dprambase[offset];
}
EXPORT_SYMBOL(cpm_dpram_addr);