/*
* sc-ip22.c: Indy cache management functions.
*
* Copyright (C) 1997, 2001 Ralf Baechle (ralf@gnu.org),
* derived from r4xx0.c by David S. Miller (dm@engr.sgi.com).
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <asm/bcache.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/bootinfo.h>
#include <asm/sgi/ip22.h>
#include <asm/sgi/mc.h>
/* Secondary cache size in bytes, if present. */
static unsigned long scache_size;
#undef DEBUG_CACHE
#define SC_SIZE 0x00080000
#define SC_LINE 32
#define CI_MASK (SC_SIZE - SC_LINE)
#define SC_INDEX(n) ((n) & CI_MASK)
static inline void indy_sc_wipe(unsigned long first, unsigned long last)
{
unsigned long tmp;
__asm__ __volatile__(
".set\tpush\t\t\t# indy_sc_wipe\n\t"
".set\tnoreorder\n\t"
".set\tmips3\n\t"
".set\tnoat\n\t"
"mfc0\t%2, $12\n\t"
"li\t$1, 0x80\t\t\t# Go 64 bit\n\t"
"mtc0\t$1, $12\n\t"
"dli\t$1, 0x9000000080000000\n\t"
"or\t%0, $1\t\t\t# first line to flush\n\t"
"or\t%1, $1\t\t\t# last line to flush\n\t"
".set\tat\n\t"
"1:\tsw\t$0, 0(%0)\n\t"
"bne\t%0, %1, 1b\n\t"
" daddu\t%0, 32\n\t"
"mtc0\t%2, $12\t\t\t# Back to 32 bit\n\t"
"nop; nop; nop; nop;\n\t"
".set\tpop"
: "=r" (first), "=r" (last), "=&r" (tmp)
: "0" (first), "1" (last));
}
static void indy_sc_wback_invalidate(unsigned long addr, unsigned long size)
{
unsigned long first_line, last_line;
unsigned long flags;
#ifdef DEBUG_CACHE
printk("indy_sc_wback_invalidate[%08lx,%08lx]", addr, size);
#endif
/* Catch bad driver code */
BUG_ON(size == 0);
/* Which lines to flush? */
first_line = SC_INDEX(addr);
last_line = SC_INDEX(addr + size - 1);
local_irq_save(flags);
if (first_line <= last_line) {
indy_sc_wipe(first_line, last_line);
goto out;
}
indy_sc_wipe(first_line, SC_SIZE - SC_LINE);
indy_sc_wipe(0, last_line);
out:
local_irq_restore(flags);
}
static void indy_sc_enable(void)
{
unsigned long addr, tmp1, tmp2;
/* This is really cool... */
#ifdef DEBUG_CACHE
printk("Enabling R4600 SCACHE\n");
#endif
__asm__ __volatile__(
".set\tpush\n\t"
".set\tnoreorder\n\t"
".set\tmips3\n\t"
"mfc0\t%2, $12\n\t"
"nop; nop; nop; nop;\n\t"
"li\t%1, 0x80\n\t"
"mtc0\t%1, $12\n\t"
"nop; nop; nop; nop;\n\t"
"li\t%0, 0x1\n\t"
"dsll\t%0, 31\n\t"
"lui\t%1, 0x9000\n\t"
"dsll32\t%1, 0\n\t"
"or\t%0, %1, %0\n\t"
"sb\t$0, 0(%0)\n\t"
"mtc0\t$0, $12\n\t"
"nop; nop; nop; nop;\n\t"
"mtc0\t%2, $12\n\t"
"nop; nop; nop; nop;\n\t"
".set\tpop"
: "=r" (tmp1), "=r" (tmp2), "=r" (addr));
}
static void indy_sc_disable(void)
{
unsigned long tmp1, tmp2, tmp3;
#ifdef DEBUG_CACHE
printk("Disabling R4600 SCACHE\n");
#endif
__asm__ __volatile__(
".set\tpush\n\t"
".set\tnoreorder\n\t"
".set\tmips3\n\t"
"li\t%0, 0x1\n\t"
"dsll\t%0, 31\n\t"
"lui\t%1, 0x9000\n\t"
"dsll32\t%1, 0\n\t"
"or\t%0, %1, %0\n\t"
"mfc0\t%2, $12\n\t"
"nop; nop; nop; nop\n\t"
"li\t%1, 0x80\n\t"
"mtc0\t%1, $12\n\t"
"nop; nop; nop; nop\n\t"
"sh\t$0, 0(%0)\n\t"
"mtc0\t$0, $12\n\t"
"nop; nop; nop; nop\n\t"
"mtc0\t%2, $12\n\t"
"nop; nop; nop; nop\n\t"
".set\tpop"
: "=r" (tmp1), "=r" (tmp2), "=r" (tmp3));
}
static inline int __init indy_sc_probe(void)
{
unsigned int size = ip22_eeprom_read(&sgimc->eeprom, 17);
if (size == 0)
return 0;
size <<= PAGE_SHIFT;
printk(KERN_INFO "R4600/R5000 SCACHE size %dK, linesize 32 bytes.\n",
size >> 10);
scache_size = size;
return 1;
}
/* XXX Check with wje if the Indy caches can differenciate between
writeback + invalidate and just invalidate. */
static struct bcache_ops indy_sc_ops = {
.bc_enable = indy_sc_enable,
.bc_disable = indy_sc_disable,
.bc_wback_inv = indy_sc_wback_invalidate,
.bc_inv = indy_sc_wback_invalidate
};
void __cpuinit indy_sc_init(void)
{
if (indy_sc_probe()) {
indy_sc_enable();
bcops = &indy_sc_ops;
}
}
