android_kernel_motorola_sm6225/arch/sh/mm/cache-sh4.c
Paul Mundt ab27f62002 sh: Calculate cache aliases on L2 caches.
Calculate the number of cache aliases on probed L2 caches, and while
we're at it, print out the detected statistics at boot time for these
also.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-09-24 17:00:45 +09:00

770 lines
20 KiB
C

/*
* arch/sh/mm/cache-sh4.c
*
* Copyright (C) 1999, 2000, 2002 Niibe Yutaka
* Copyright (C) 2001 - 2007 Paul Mundt
* Copyright (C) 2003 Richard Curnow
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/mutex.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
/*
* The maximum number of pages we support up to when doing ranged dcache
* flushing. Anything exceeding this will simply flush the dcache in its
* entirety.
*/
#define MAX_DCACHE_PAGES 64 /* XXX: Tune for ways */
static void __flush_dcache_segment_1way(unsigned long start,
unsigned long extent);
static void __flush_dcache_segment_2way(unsigned long start,
unsigned long extent);
static void __flush_dcache_segment_4way(unsigned long start,
unsigned long extent);
static void __flush_cache_4096(unsigned long addr, unsigned long phys,
unsigned long exec_offset);
/*
* This is initialised here to ensure that it is not placed in the BSS. If
* that were to happen, note that cache_init gets called before the BSS is
* cleared, so this would get nulled out which would be hopeless.
*/
static void (*__flush_dcache_segment_fn)(unsigned long, unsigned long) =
(void (*)(unsigned long, unsigned long))0xdeadbeef;
static void compute_alias(struct cache_info *c)
{
c->alias_mask = ((c->sets - 1) << c->entry_shift) & ~(PAGE_SIZE - 1);
c->n_aliases = c->alias_mask ? (c->alias_mask >> PAGE_SHIFT) + 1 : 0;
}
static void __init emit_cache_params(void)
{
printk("PVR=%08x CVR=%08x PRR=%08x\n",
ctrl_inl(CCN_PVR),
ctrl_inl(CCN_CVR),
ctrl_inl(CCN_PRR));
printk("I-cache : n_ways=%d n_sets=%d way_incr=%d\n",
boot_cpu_data.icache.ways,
boot_cpu_data.icache.sets,
boot_cpu_data.icache.way_incr);
printk("I-cache : entry_mask=0x%08x alias_mask=0x%08x n_aliases=%d\n",
boot_cpu_data.icache.entry_mask,
boot_cpu_data.icache.alias_mask,
boot_cpu_data.icache.n_aliases);
printk("D-cache : n_ways=%d n_sets=%d way_incr=%d\n",
boot_cpu_data.dcache.ways,
boot_cpu_data.dcache.sets,
boot_cpu_data.dcache.way_incr);
printk("D-cache : entry_mask=0x%08x alias_mask=0x%08x n_aliases=%d\n",
boot_cpu_data.dcache.entry_mask,
boot_cpu_data.dcache.alias_mask,
boot_cpu_data.dcache.n_aliases);
/*
* Emit Secondary Cache parameters if the CPU has a probed L2.
*/
if (boot_cpu_data.flags & CPU_HAS_L2_CACHE) {
printk("S-cache : n_ways=%d n_sets=%d way_incr=%d\n",
boot_cpu_data.scache.ways,
boot_cpu_data.scache.sets,
boot_cpu_data.scache.way_incr);
printk("S-cache : entry_mask=0x%08x alias_mask=0x%08x n_aliases=%d\n",
boot_cpu_data.scache.entry_mask,
boot_cpu_data.scache.alias_mask,
boot_cpu_data.scache.n_aliases);
}
if (!__flush_dcache_segment_fn)
panic("unknown number of cache ways\n");
}
/*
* SH-4 has virtually indexed and physically tagged cache.
*/
void __init p3_cache_init(void)
{
compute_alias(&boot_cpu_data.icache);
compute_alias(&boot_cpu_data.dcache);
compute_alias(&boot_cpu_data.scache);
switch (boot_cpu_data.dcache.ways) {
case 1:
__flush_dcache_segment_fn = __flush_dcache_segment_1way;
break;
case 2:
__flush_dcache_segment_fn = __flush_dcache_segment_2way;
break;
case 4:
__flush_dcache_segment_fn = __flush_dcache_segment_4way;
break;
default:
__flush_dcache_segment_fn = NULL;
break;
}
emit_cache_params();
}
/*
* Write back the dirty D-caches, but not invalidate them.
*
* START: Virtual Address (U0, P1, or P3)
* SIZE: Size of the region.
*/
void __flush_wback_region(void *start, int size)
{
unsigned long v;
unsigned long begin, end;
begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
& ~(L1_CACHE_BYTES-1);
for (v = begin; v < end; v+=L1_CACHE_BYTES) {
asm volatile("ocbwb %0"
: /* no output */
: "m" (__m(v)));
}
}
/*
* Write back the dirty D-caches and invalidate them.
*
* START: Virtual Address (U0, P1, or P3)
* SIZE: Size of the region.
*/
void __flush_purge_region(void *start, int size)
{
unsigned long v;
unsigned long begin, end;
begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
& ~(L1_CACHE_BYTES-1);
for (v = begin; v < end; v+=L1_CACHE_BYTES) {
asm volatile("ocbp %0"
: /* no output */
: "m" (__m(v)));
}
}
/*
* No write back please
*/
void __flush_invalidate_region(void *start, int size)
{
unsigned long v;
unsigned long begin, end;
begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
& ~(L1_CACHE_BYTES-1);
for (v = begin; v < end; v+=L1_CACHE_BYTES) {
asm volatile("ocbi %0"
: /* no output */
: "m" (__m(v)));
}
}
/*
* Write back the range of D-cache, and purge the I-cache.
*
* Called from kernel/module.c:sys_init_module and routine for a.out format.
*/
void flush_icache_range(unsigned long start, unsigned long end)
{
flush_cache_all();
}
/*
* Write back the D-cache and purge the I-cache for signal trampoline.
* .. which happens to be the same behavior as flush_icache_range().
* So, we simply flush out a line.
*/
void flush_cache_sigtramp(unsigned long addr)
{
unsigned long v, index;
unsigned long flags;
int i;
v = addr & ~(L1_CACHE_BYTES-1);
asm volatile("ocbwb %0"
: /* no output */
: "m" (__m(v)));
index = CACHE_IC_ADDRESS_ARRAY |
(v & boot_cpu_data.icache.entry_mask);
local_irq_save(flags);
jump_to_P2();
for (i = 0; i < boot_cpu_data.icache.ways;
i++, index += boot_cpu_data.icache.way_incr)
ctrl_outl(0, index); /* Clear out Valid-bit */
back_to_P1();
wmb();
local_irq_restore(flags);
}
static inline void flush_cache_4096(unsigned long start,
unsigned long phys)
{
unsigned long flags, exec_offset = 0;
/*
* All types of SH-4 require PC to be in P2 to operate on the I-cache.
* Some types of SH-4 require PC to be in P2 to operate on the D-cache.
*/
if ((boot_cpu_data.flags & CPU_HAS_P2_FLUSH_BUG) ||
(start < CACHE_OC_ADDRESS_ARRAY))
exec_offset = 0x20000000;
local_irq_save(flags);
__flush_cache_4096(start | SH_CACHE_ASSOC,
P1SEGADDR(phys), exec_offset);
local_irq_restore(flags);
}
/*
* Write back & invalidate the D-cache of the page.
* (To avoid "alias" issues)
*/
void flush_dcache_page(struct page *page)
{
if (test_bit(PG_mapped, &page->flags)) {
unsigned long phys = PHYSADDR(page_address(page));
unsigned long addr = CACHE_OC_ADDRESS_ARRAY;
int i, n;
/* Loop all the D-cache */
n = boot_cpu_data.dcache.n_aliases;
for (i = 0; i < n; i++, addr += 4096)
flush_cache_4096(addr, phys);
}
wmb();
}
/* TODO: Selective icache invalidation through IC address array.. */
static inline void flush_icache_all(void)
{
unsigned long flags, ccr;
local_irq_save(flags);
jump_to_P2();
/* Flush I-cache */
ccr = ctrl_inl(CCR);
ccr |= CCR_CACHE_ICI;
ctrl_outl(ccr, CCR);
/*
* back_to_P1() will take care of the barrier for us, don't add
* another one!
*/
back_to_P1();
local_irq_restore(flags);
}
void flush_dcache_all(void)
{
(*__flush_dcache_segment_fn)(0UL, boot_cpu_data.dcache.way_size);
wmb();
}
void flush_cache_all(void)
{
flush_dcache_all();
flush_icache_all();
}
static void __flush_cache_mm(struct mm_struct *mm, unsigned long start,
unsigned long end)
{
unsigned long d = 0, p = start & PAGE_MASK;
unsigned long alias_mask = boot_cpu_data.dcache.alias_mask;
unsigned long n_aliases = boot_cpu_data.dcache.n_aliases;
unsigned long select_bit;
unsigned long all_aliases_mask;
unsigned long addr_offset;
pgd_t *dir;
pmd_t *pmd;
pud_t *pud;
pte_t *pte;
int i;
dir = pgd_offset(mm, p);
pud = pud_offset(dir, p);
pmd = pmd_offset(pud, p);
end = PAGE_ALIGN(end);
all_aliases_mask = (1 << n_aliases) - 1;
do {
if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) {
p &= PMD_MASK;
p += PMD_SIZE;
pmd++;
continue;
}
pte = pte_offset_kernel(pmd, p);
do {
unsigned long phys;
pte_t entry = *pte;
if (!(pte_val(entry) & _PAGE_PRESENT)) {
pte++;
p += PAGE_SIZE;
continue;
}
phys = pte_val(entry) & PTE_PHYS_MASK;
if ((p ^ phys) & alias_mask) {
d |= 1 << ((p & alias_mask) >> PAGE_SHIFT);
d |= 1 << ((phys & alias_mask) >> PAGE_SHIFT);
if (d == all_aliases_mask)
goto loop_exit;
}
pte++;
p += PAGE_SIZE;
} while (p < end && ((unsigned long)pte & ~PAGE_MASK));
pmd++;
} while (p < end);
loop_exit:
addr_offset = 0;
select_bit = 1;
for (i = 0; i < n_aliases; i++) {
if (d & select_bit) {
(*__flush_dcache_segment_fn)(addr_offset, PAGE_SIZE);
wmb();
}
select_bit <<= 1;
addr_offset += PAGE_SIZE;
}
}
/*
* Note : (RPC) since the caches are physically tagged, the only point
* of flush_cache_mm for SH-4 is to get rid of aliases from the
* D-cache. The assumption elsewhere, e.g. flush_cache_range, is that
* lines can stay resident so long as the virtual address they were
* accessed with (hence cache set) is in accord with the physical
* address (i.e. tag). It's no different here. So I reckon we don't
* need to flush the I-cache, since aliases don't matter for that. We
* should try that.
*
* Caller takes mm->mmap_sem.
*/
void flush_cache_mm(struct mm_struct *mm)
{
/*
* If cache is only 4k-per-way, there are never any 'aliases'. Since
* the cache is physically tagged, the data can just be left in there.
*/
if (boot_cpu_data.dcache.n_aliases == 0)
return;
/*
* Don't bother groveling around the dcache for the VMA ranges
* if there are too many PTEs to make it worthwhile.
*/
if (mm->nr_ptes >= MAX_DCACHE_PAGES)
flush_dcache_all();
else {
struct vm_area_struct *vma;
/*
* In this case there are reasonably sized ranges to flush,
* iterate through the VMA list and take care of any aliases.
*/
for (vma = mm->mmap; vma; vma = vma->vm_next)
__flush_cache_mm(mm, vma->vm_start, vma->vm_end);
}
/* Only touch the icache if one of the VMAs has VM_EXEC set. */
if (mm->exec_vm)
flush_icache_all();
}
/*
* Write back and invalidate I/D-caches for the page.
*
* ADDR: Virtual Address (U0 address)
* PFN: Physical page number
*/
void flush_cache_page(struct vm_area_struct *vma, unsigned long address,
unsigned long pfn)
{
unsigned long phys = pfn << PAGE_SHIFT;
unsigned int alias_mask;
alias_mask = boot_cpu_data.dcache.alias_mask;
/* We only need to flush D-cache when we have alias */
if ((address^phys) & alias_mask) {
/* Loop 4K of the D-cache */
flush_cache_4096(
CACHE_OC_ADDRESS_ARRAY | (address & alias_mask),
phys);
/* Loop another 4K of the D-cache */
flush_cache_4096(
CACHE_OC_ADDRESS_ARRAY | (phys & alias_mask),
phys);
}
alias_mask = boot_cpu_data.icache.alias_mask;
if (vma->vm_flags & VM_EXEC) {
/*
* Evict entries from the portion of the cache from which code
* may have been executed at this address (virtual). There's
* no need to evict from the portion corresponding to the
* physical address as for the D-cache, because we know the
* kernel has never executed the code through its identity
* translation.
*/
flush_cache_4096(
CACHE_IC_ADDRESS_ARRAY | (address & alias_mask),
phys);
}
}
/*
* Write back and invalidate D-caches.
*
* START, END: Virtual Address (U0 address)
*
* NOTE: We need to flush the _physical_ page entry.
* Flushing the cache lines for U0 only isn't enough.
* We need to flush for P1 too, which may contain aliases.
*/
void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
/*
* If cache is only 4k-per-way, there are never any 'aliases'. Since
* the cache is physically tagged, the data can just be left in there.
*/
if (boot_cpu_data.dcache.n_aliases == 0)
return;
/*
* Don't bother with the lookup and alias check if we have a
* wide range to cover, just blow away the dcache in its
* entirety instead. -- PFM.
*/
if (((end - start) >> PAGE_SHIFT) >= MAX_DCACHE_PAGES)
flush_dcache_all();
else
__flush_cache_mm(vma->vm_mm, start, end);
if (vma->vm_flags & VM_EXEC) {
/*
* TODO: Is this required??? Need to look at how I-cache
* coherency is assured when new programs are loaded to see if
* this matters.
*/
flush_icache_all();
}
}
/*
* flush_icache_user_range
* @vma: VMA of the process
* @page: page
* @addr: U0 address
* @len: length of the range (< page size)
*/
void flush_icache_user_range(struct vm_area_struct *vma,
struct page *page, unsigned long addr, int len)
{
flush_cache_page(vma, addr, page_to_pfn(page));
mb();
}
/**
* __flush_cache_4096
*
* @addr: address in memory mapped cache array
* @phys: P1 address to flush (has to match tags if addr has 'A' bit
* set i.e. associative write)
* @exec_offset: set to 0x20000000 if flush has to be executed from P2
* region else 0x0
*
* The offset into the cache array implied by 'addr' selects the
* 'colour' of the virtual address range that will be flushed. The
* operation (purge/write-back) is selected by the lower 2 bits of
* 'phys'.
*/
static void __flush_cache_4096(unsigned long addr, unsigned long phys,
unsigned long exec_offset)
{
int way_count;
unsigned long base_addr = addr;
struct cache_info *dcache;
unsigned long way_incr;
unsigned long a, ea, p;
unsigned long temp_pc;
dcache = &boot_cpu_data.dcache;
/* Write this way for better assembly. */
way_count = dcache->ways;
way_incr = dcache->way_incr;
/*
* Apply exec_offset (i.e. branch to P2 if required.).
*
* FIXME:
*
* If I write "=r" for the (temp_pc), it puts this in r6 hence
* trashing exec_offset before it's been added on - why? Hence
* "=&r" as a 'workaround'
*/
asm volatile("mov.l 1f, %0\n\t"
"add %1, %0\n\t"
"jmp @%0\n\t"
"nop\n\t"
".balign 4\n\t"
"1: .long 2f\n\t"
"2:\n" : "=&r" (temp_pc) : "r" (exec_offset));
/*
* We know there will be >=1 iteration, so write as do-while to avoid
* pointless nead-of-loop check for 0 iterations.
*/
do {
ea = base_addr + PAGE_SIZE;
a = base_addr;
p = phys;
do {
*(volatile unsigned long *)a = p;
/*
* Next line: intentionally not p+32, saves an add, p
* will do since only the cache tag bits need to
* match.
*/
*(volatile unsigned long *)(a+32) = p;
a += 64;
p += 64;
} while (a < ea);
base_addr += way_incr;
} while (--way_count != 0);
}
/*
* Break the 1, 2 and 4 way variants of this out into separate functions to
* avoid nearly all the overhead of having the conditional stuff in the function
* bodies (+ the 1 and 2 way cases avoid saving any registers too).
*/
static void __flush_dcache_segment_1way(unsigned long start,
unsigned long extent_per_way)
{
unsigned long orig_sr, sr_with_bl;
unsigned long base_addr;
unsigned long way_incr, linesz, way_size;
struct cache_info *dcache;
register unsigned long a0, a0e;
asm volatile("stc sr, %0" : "=r" (orig_sr));
sr_with_bl = orig_sr | (1<<28);
base_addr = ((unsigned long)&empty_zero_page[0]);
/*
* The previous code aligned base_addr to 16k, i.e. the way_size of all
* existing SH-4 D-caches. Whilst I don't see a need to have this
* aligned to any better than the cache line size (which it will be
* anyway by construction), let's align it to at least the way_size of
* any existing or conceivable SH-4 D-cache. -- RPC
*/
base_addr = ((base_addr >> 16) << 16);
base_addr |= start;
dcache = &boot_cpu_data.dcache;
linesz = dcache->linesz;
way_incr = dcache->way_incr;
way_size = dcache->way_size;
a0 = base_addr;
a0e = base_addr + extent_per_way;
do {
asm volatile("ldc %0, sr" : : "r" (sr_with_bl));
asm volatile("movca.l r0, @%0\n\t"
"ocbi @%0" : : "r" (a0));
a0 += linesz;
asm volatile("movca.l r0, @%0\n\t"
"ocbi @%0" : : "r" (a0));
a0 += linesz;
asm volatile("movca.l r0, @%0\n\t"
"ocbi @%0" : : "r" (a0));
a0 += linesz;
asm volatile("movca.l r0, @%0\n\t"
"ocbi @%0" : : "r" (a0));
asm volatile("ldc %0, sr" : : "r" (orig_sr));
a0 += linesz;
} while (a0 < a0e);
}
static void __flush_dcache_segment_2way(unsigned long start,
unsigned long extent_per_way)
{
unsigned long orig_sr, sr_with_bl;
unsigned long base_addr;
unsigned long way_incr, linesz, way_size;
struct cache_info *dcache;
register unsigned long a0, a1, a0e;
asm volatile("stc sr, %0" : "=r" (orig_sr));
sr_with_bl = orig_sr | (1<<28);
base_addr = ((unsigned long)&empty_zero_page[0]);
/* See comment under 1-way above */
base_addr = ((base_addr >> 16) << 16);
base_addr |= start;
dcache = &boot_cpu_data.dcache;
linesz = dcache->linesz;
way_incr = dcache->way_incr;
way_size = dcache->way_size;
a0 = base_addr;
a1 = a0 + way_incr;
a0e = base_addr + extent_per_way;
do {
asm volatile("ldc %0, sr" : : "r" (sr_with_bl));
asm volatile("movca.l r0, @%0\n\t"
"movca.l r0, @%1\n\t"
"ocbi @%0\n\t"
"ocbi @%1" : :
"r" (a0), "r" (a1));
a0 += linesz;
a1 += linesz;
asm volatile("movca.l r0, @%0\n\t"
"movca.l r0, @%1\n\t"
"ocbi @%0\n\t"
"ocbi @%1" : :
"r" (a0), "r" (a1));
a0 += linesz;
a1 += linesz;
asm volatile("movca.l r0, @%0\n\t"
"movca.l r0, @%1\n\t"
"ocbi @%0\n\t"
"ocbi @%1" : :
"r" (a0), "r" (a1));
a0 += linesz;
a1 += linesz;
asm volatile("movca.l r0, @%0\n\t"
"movca.l r0, @%1\n\t"
"ocbi @%0\n\t"
"ocbi @%1" : :
"r" (a0), "r" (a1));
asm volatile("ldc %0, sr" : : "r" (orig_sr));
a0 += linesz;
a1 += linesz;
} while (a0 < a0e);
}
static void __flush_dcache_segment_4way(unsigned long start,
unsigned long extent_per_way)
{
unsigned long orig_sr, sr_with_bl;
unsigned long base_addr;
unsigned long way_incr, linesz, way_size;
struct cache_info *dcache;
register unsigned long a0, a1, a2, a3, a0e;
asm volatile("stc sr, %0" : "=r" (orig_sr));
sr_with_bl = orig_sr | (1<<28);
base_addr = ((unsigned long)&empty_zero_page[0]);
/* See comment under 1-way above */
base_addr = ((base_addr >> 16) << 16);
base_addr |= start;
dcache = &boot_cpu_data.dcache;
linesz = dcache->linesz;
way_incr = dcache->way_incr;
way_size = dcache->way_size;
a0 = base_addr;
a1 = a0 + way_incr;
a2 = a1 + way_incr;
a3 = a2 + way_incr;
a0e = base_addr + extent_per_way;
do {
asm volatile("ldc %0, sr" : : "r" (sr_with_bl));
asm volatile("movca.l r0, @%0\n\t"
"movca.l r0, @%1\n\t"
"movca.l r0, @%2\n\t"
"movca.l r0, @%3\n\t"
"ocbi @%0\n\t"
"ocbi @%1\n\t"
"ocbi @%2\n\t"
"ocbi @%3\n\t" : :
"r" (a0), "r" (a1), "r" (a2), "r" (a3));
a0 += linesz;
a1 += linesz;
a2 += linesz;
a3 += linesz;
asm volatile("movca.l r0, @%0\n\t"
"movca.l r0, @%1\n\t"
"movca.l r0, @%2\n\t"
"movca.l r0, @%3\n\t"
"ocbi @%0\n\t"
"ocbi @%1\n\t"
"ocbi @%2\n\t"
"ocbi @%3\n\t" : :
"r" (a0), "r" (a1), "r" (a2), "r" (a3));
a0 += linesz;
a1 += linesz;
a2 += linesz;
a3 += linesz;
asm volatile("movca.l r0, @%0\n\t"
"movca.l r0, @%1\n\t"
"movca.l r0, @%2\n\t"
"movca.l r0, @%3\n\t"
"ocbi @%0\n\t"
"ocbi @%1\n\t"
"ocbi @%2\n\t"
"ocbi @%3\n\t" : :
"r" (a0), "r" (a1), "r" (a2), "r" (a3));
a0 += linesz;
a1 += linesz;
a2 += linesz;
a3 += linesz;
asm volatile("movca.l r0, @%0\n\t"
"movca.l r0, @%1\n\t"
"movca.l r0, @%2\n\t"
"movca.l r0, @%3\n\t"
"ocbi @%0\n\t"
"ocbi @%1\n\t"
"ocbi @%2\n\t"
"ocbi @%3\n\t" : :
"r" (a0), "r" (a1), "r" (a2), "r" (a3));
asm volatile("ldc %0, sr" : : "r" (orig_sr));
a0 += linesz;
a1 += linesz;
a2 += linesz;
a3 += linesz;
} while (a0 < a0e);
}