/*
* r2300.c: R2000 and R3000 specific mmu/cache code.
*
* Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
*
* with a lot of changes to make this thing work for R3000s
* Tx39XX R4k style caches added. HK
* Copyright (C) 1998, 1999, 2000 Harald Koerfgen
* Copyright (C) 1998 Gleb Raiko & Vladimir Roganov
* Copyright (C) 2001, 2004 Maciej W. Rozycki
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
#include <asm/system.h>
#include <asm/isadep.h>
#include <asm/io.h>
#include <asm/bootinfo.h>
#include <asm/cpu.h>
static unsigned long icache_size, dcache_size; /* Size in bytes */
static unsigned long icache_lsize, dcache_lsize; /* Size in bytes */
#undef DEBUG_CACHE
unsigned long __init r3k_cache_size(unsigned long ca_flags)
{
unsigned long flags, status, dummy, size;
volatile unsigned long *p;
p = (volatile unsigned long *) KSEG0;
flags = read_c0_status();
/* isolate cache space */
write_c0_status((ca_flags|flags)&~ST0_IEC);
*p = 0xa5a55a5a;
dummy = *p;
status = read_c0_status();
if (dummy != 0xa5a55a5a || (status & ST0_CM)) {
size = 0;
} else {
for (size = 128; size <= 0x40000; size <<= 1)
*(p + size) = 0;
*p = -1;
for (size = 128;
(size <= 0x40000) && (*(p + size) == 0);
size <<= 1)
;
if (size > 0x40000)
size = 0;
}
write_c0_status(flags);
return size * sizeof(*p);
}
unsigned long __init r3k_cache_lsize(unsigned long ca_flags)
{
unsigned long flags, status, lsize, i;
volatile unsigned long *p;
p = (volatile unsigned long *) KSEG0;
flags = read_c0_status();
/* isolate cache space */
write_c0_status((ca_flags|flags)&~ST0_IEC);
for (i = 0; i < 128; i++)
*(p + i) = 0;
*(volatile unsigned char *)p = 0;
for (lsize = 1; lsize < 128; lsize <<= 1) {
*(p + lsize);
status = read_c0_status();
if (!(status & ST0_CM))
break;
}
for (i = 0; i < 128; i += lsize)
*(volatile unsigned char *)(p + i) = 0;
write_c0_status(flags);
return lsize * sizeof(*p);
}
static void __init r3k_probe_cache(void)
{
dcache_size = r3k_cache_size(ST0_ISC);
if (dcache_size)
dcache_lsize = r3k_cache_lsize(ST0_ISC);
icache_size = r3k_cache_size(ST0_ISC|ST0_SWC);
if (icache_size)
icache_lsize = r3k_cache_lsize(ST0_ISC|ST0_SWC);
}
static void r3k_flush_icache_range(unsigned long start, unsigned long end)
{
unsigned long size, i, flags;
volatile unsigned char *p;
size = end - start;
if (size > icache_size || KSEGX(start) != KSEG0) {
start = KSEG0;
size = icache_size;
}
p = (char *)start;
flags = read_c0_status();
/* isolate cache space */
write_c0_status((ST0_ISC|ST0_SWC|flags)&~ST0_IEC);
for (i = 0; i < size; i += 0x080) {
asm ( "sb\t$0, 0x000(%0)\n\t"
"sb\t$0, 0x004(%0)\n\t"
"sb\t$0, 0x008(%0)\n\t"
"sb\t$0, 0x00c(%0)\n\t"
"sb\t$0, 0x010(%0)\n\t"
"sb\t$0, 0x014(%0)\n\t"
"sb\t$0, 0x018(%0)\n\t"
"sb\t$0, 0x01c(%0)\n\t"
"sb\t$0, 0x020(%0)\n\t"
"sb\t$0, 0x024(%0)\n\t"
"sb\t$0, 0x028(%0)\n\t"
"sb\t$0, 0x02c(%0)\n\t"
"sb\t$0, 0x030(%0)\n\t"
"sb\t$0, 0x034(%0)\n\t"
"sb\t$0, 0x038(%0)\n\t"
"sb\t$0, 0x03c(%0)\n\t"
"sb\t$0, 0x040(%0)\n\t"
"sb\t$0, 0x044(%0)\n\t"
"sb\t$0, 0x048(%0)\n\t"
"sb\t$0, 0x04c(%0)\n\t"
"sb\t$0, 0x050(%0)\n\t"
"sb\t$0, 0x054(%0)\n\t"
"sb\t$0, 0x058(%0)\n\t"
"sb\t$0, 0x05c(%0)\n\t"
"sb\t$0, 0x060(%0)\n\t"
"sb\t$0, 0x064(%0)\n\t"
"sb\t$0, 0x068(%0)\n\t"
"sb\t$0, 0x06c(%0)\n\t"
"sb\t$0, 0x070(%0)\n\t"
"sb\t$0, 0x074(%0)\n\t"
"sb\t$0, 0x078(%0)\n\t"
"sb\t$0, 0x07c(%0)\n\t"
: : "r" (p) );
p += 0x080;
}
write_c0_status(flags);
}
static void r3k_flush_dcache_range(unsigned long start, unsigned long end)
{
unsigned long size, i, flags;
volatile unsigned char *p;
size = end - start;
if (size > dcache_size || KSEGX(start) != KSEG0) {
start = KSEG0;
size = dcache_size;
}
p = (char *)start;
flags = read_c0_status();
/* isolate cache space */
write_c0_status((ST0_ISC|flags)&~ST0_IEC);
for (i = 0; i < size; i += 0x080) {
asm ( "sb\t$0, 0x000(%0)\n\t"
"sb\t$0, 0x004(%0)\n\t"
"sb\t$0, 0x008(%0)\n\t"
"sb\t$0, 0x00c(%0)\n\t"
"sb\t$0, 0x010(%0)\n\t"
"sb\t$0, 0x014(%0)\n\t"
"sb\t$0, 0x018(%0)\n\t"
"sb\t$0, 0x01c(%0)\n\t"
"sb\t$0, 0x020(%0)\n\t"
"sb\t$0, 0x024(%0)\n\t"
"sb\t$0, 0x028(%0)\n\t"
"sb\t$0, 0x02c(%0)\n\t"
"sb\t$0, 0x030(%0)\n\t"
"sb\t$0, 0x034(%0)\n\t"
"sb\t$0, 0x038(%0)\n\t"
"sb\t$0, 0x03c(%0)\n\t"
"sb\t$0, 0x040(%0)\n\t"
"sb\t$0, 0x044(%0)\n\t"
"sb\t$0, 0x048(%0)\n\t"
"sb\t$0, 0x04c(%0)\n\t"
"sb\t$0, 0x050(%0)\n\t"
"sb\t$0, 0x054(%0)\n\t"
"sb\t$0, 0x058(%0)\n\t"
"sb\t$0, 0x05c(%0)\n\t"
"sb\t$0, 0x060(%0)\n\t"
"sb\t$0, 0x064(%0)\n\t"
"sb\t$0, 0x068(%0)\n\t"
"sb\t$0, 0x06c(%0)\n\t"
"sb\t$0, 0x070(%0)\n\t"
"sb\t$0, 0x074(%0)\n\t"
"sb\t$0, 0x078(%0)\n\t"
"sb\t$0, 0x07c(%0)\n\t"
: : "r" (p) );
p += 0x080;
}
write_c0_status(flags);
}
static inline unsigned long get_phys_page (unsigned long addr,
struct mm_struct *mm)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
unsigned long physpage;
pgd = pgd_offset(mm, addr);
pud = pud_offset(pgd, addr);
pmd = pmd_offset(pud, addr);
pte = pte_offset(pmd, addr);
if ((physpage = pte_val(*pte)) & _PAGE_VALID)
return KSEG0ADDR(physpage & PAGE_MASK);
return 0;
}
static inline void r3k_flush_cache_all(void)
{
}
static inline void r3k___flush_cache_all(void)
{
r3k_flush_dcache_range(KSEG0, KSEG0 + dcache_size);
r3k_flush_icache_range(KSEG0, KSEG0 + icache_size);
}
static void r3k_flush_cache_mm(struct mm_struct *mm)
{
}
static void r3k_flush_cache_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
}
static void r3k_flush_cache_page(struct vm_area_struct *vma, unsigned long page, unsigned long pfn)
{
}
static void local_r3k_flush_data_cache_page(unsigned long addr)
{
}
static void r3k_flush_data_cache_page(unsigned long addr)
{
}
static void r3k_flush_cache_sigtramp(unsigned long addr)
{
unsigned long flags;
#ifdef DEBUG_CACHE
printk("csigtramp[%08lx]", addr);
#endif
flags = read_c0_status();
write_c0_status(flags&~ST0_IEC);
/* Fill the TLB to avoid an exception with caches isolated. */
asm ( "lw\t$0, 0x000(%0)\n\t"
"lw\t$0, 0x004(%0)\n\t"
: : "r" (addr) );
write_c0_status((ST0_ISC|ST0_SWC|flags)&~ST0_IEC);
asm ( "sb\t$0, 0x000(%0)\n\t"
"sb\t$0, 0x004(%0)\n\t"
: : "r" (addr) );
write_c0_status(flags);
}
static void r3k_dma_cache_wback_inv(unsigned long start, unsigned long size)
{
/* Catch bad driver code */
BUG_ON(size == 0);
iob();
r3k_flush_dcache_range(start, start + size);
}
void __init r3k_cache_init(void)
{
extern void build_clear_page(void);
extern void build_copy_page(void);
r3k_probe_cache();
flush_cache_all = r3k_flush_cache_all;
__flush_cache_all = r3k___flush_cache_all;
flush_cache_mm = r3k_flush_cache_mm;
flush_cache_range = r3k_flush_cache_range;
flush_cache_page = r3k_flush_cache_page;
flush_icache_range = r3k_flush_icache_range;
flush_cache_sigtramp = r3k_flush_cache_sigtramp;
local_flush_data_cache_page = local_r3k_flush_data_cache_page;
flush_data_cache_page = r3k_flush_data_cache_page;
_dma_cache_wback_inv = r3k_dma_cache_wback_inv;
_dma_cache_wback = r3k_dma_cache_wback_inv;
_dma_cache_inv = r3k_dma_cache_wback_inv;
printk("Primary instruction cache %ldkB, linesize %ld bytes.\n",
icache_size >> 10, icache_lsize);
printk("Primary data cache %ldkB, linesize %ld bytes.\n",
dcache_size >> 10, dcache_lsize);
build_clear_page();
build_copy_page();
}
