* arch/sh/mm/cache-sh4.c
*
* Copyright (C) 1999, 2000, 2002 Niibe Yutaka
- * Copyright (C) 2001 - 2007 Paul Mundt
+ * Copyright (C) 2001 - 2009 Paul Mundt
* Copyright (C) 2003 Richard Curnow
* Copyright (c) 2007 STMicroelectronics (R&D) Ltd.
*
#include <linux/io.h>
#include <linux/mutex.h>
#include <linux/fs.h>
+#include <linux/highmem.h>
+#include <asm/pgtable.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
* flushing. Anything exceeding this will simply flush the dcache in its
* entirety.
*/
-#define MAX_DCACHE_PAGES 64 /* XXX: Tune for ways */
#define MAX_ICACHE_PAGES 32
static void __flush_cache_one(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;
-
/*
* Write back the range of D-cache, and purge the I-cache.
*
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.
+ * All types of SH-4 require PC to be uncached to operate on the I-cache.
+ * Some types of SH-4 require PC to be uncached to operate on the D-cache.
*/
if ((boot_cpu_data.flags & CPU_HAS_P2_FLUSH_BUG) ||
(start < CACHE_OC_ADDRESS_ARRAY))
- exec_offset = 0x20000000;
+ exec_offset = cached_to_uncached;
local_irq_save(flags);
- __flush_cache_one(start | SH_CACHE_ASSOC, P1SEGADDR(phys), exec_offset);
+ __flush_cache_one(start, phys, exec_offset);
local_irq_restore(flags);
}
else
#endif
{
- unsigned long phys = PHYSADDR(page_address(page));
+ unsigned long phys = page_to_phys(page);
unsigned long addr = CACHE_OC_ADDRESS_ARRAY;
int i, n;
local_irq_restore(flags);
}
-static inline void flush_dcache_all(void)
+static void flush_dcache_all(void)
{
- (*__flush_dcache_segment_fn)(0UL, boot_cpu_data.dcache.way_size);
- wmb();
+ unsigned long addr, end_addr, entry_offset;
+
+ end_addr = CACHE_OC_ADDRESS_ARRAY +
+ (current_cpu_data.dcache.sets <<
+ current_cpu_data.dcache.entry_shift) *
+ current_cpu_data.dcache.ways;
+
+ entry_offset = 1 << current_cpu_data.dcache.entry_shift;
+
+ for (addr = CACHE_OC_ADDRESS_ARRAY; addr < end_addr; ) {
+ __raw_writel(0, addr); addr += entry_offset;
+ __raw_writel(0, addr); addr += entry_offset;
+ __raw_writel(0, addr); addr += entry_offset;
+ __raw_writel(0, addr); addr += entry_offset;
+ __raw_writel(0, addr); addr += entry_offset;
+ __raw_writel(0, addr); addr += entry_offset;
+ __raw_writel(0, addr); addr += entry_offset;
+ __raw_writel(0, addr); addr += entry_offset;
+ }
}
static void sh4_flush_cache_all(void *unused)
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.
+ * address (i.e. tag). It's no different here.
*
* Caller takes mm->mmap_sem.
*/
if (cpu_context(smp_processor_id(), mm) == NO_CONTEXT)
return;
- /*
- * 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();
+ flush_dcache_all();
}
/*
{
struct flusher_data *data = args;
struct vm_area_struct *vma;
+ struct page *page;
unsigned long address, pfn, phys;
- unsigned int alias_mask;
+ int map_coherent = 0;
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+ void *vaddr;
vma = data->vma;
- address = data->addr1;
+ address = data->addr1 & PAGE_MASK;
pfn = data->addr2;
phys = pfn << PAGE_SHIFT;
+ page = pfn_to_page(pfn);
if (cpu_context(smp_processor_id(), vma->vm_mm) == NO_CONTEXT)
return;
- 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_one(
- CACHE_OC_ADDRESS_ARRAY | (address & alias_mask),
- phys);
- /* Loop another 4K of the D-cache */
- flush_cache_one(
- CACHE_OC_ADDRESS_ARRAY | (phys & alias_mask),
- phys);
- }
+ pgd = pgd_offset(vma->vm_mm, address);
+ pud = pud_offset(pgd, address);
+ pmd = pmd_offset(pud, address);
+ pte = pte_offset_kernel(pmd, address);
+
+ /* If the page isn't present, there is nothing to do here. */
+ if (!(pte_val(*pte) & _PAGE_PRESENT))
+ return;
- alias_mask = boot_cpu_data.icache.alias_mask;
- if (vma->vm_flags & VM_EXEC) {
+ if ((vma->vm_mm == current->active_mm))
+ vaddr = NULL;
+ else {
/*
- * 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.
+ * Use kmap_coherent or kmap_atomic to do flushes for
+ * another ASID than the current one.
*/
- flush_cache_one(
- CACHE_IC_ADDRESS_ARRAY | (address & alias_mask),
- phys);
+ map_coherent = (current_cpu_data.dcache.n_aliases &&
+ !test_bit(PG_dcache_dirty, &page->flags) &&
+ page_mapped(page));
+ if (map_coherent)
+ vaddr = kmap_coherent(page, address);
+ else
+ vaddr = kmap_atomic(page, KM_USER0);
+
+ address = (unsigned long)vaddr;
+ }
+
+ flush_cache_one(CACHE_OC_ADDRESS_ARRAY |
+ (address & shm_align_mask), phys);
+
+ if (vma->vm_flags & VM_EXEC)
+ flush_icache_all();
+
+ if (vaddr) {
+ if (map_coherent)
+ kunmap_coherent(vaddr);
+ else
+ kunmap_atomic(vaddr, KM_USER0);
}
}
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);
+ flush_dcache_all();
- 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.
- */
+ if (vma->vm_flags & VM_EXEC)
flush_icache_all();
- }
}
/**
} 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).
- *
- * We want to eliminate unnecessary bus transactions, so this code uses
- * a non-obvious technique.
- *
- * Loop over a cache way sized block of, one cache line at a time. For each
- * line, use movca.a to cause the current cache line contents to be written
- * back, but without reading anything from main memory. However this has the
- * side effect that the cache is now caching that memory location. So follow
- * this with a cache invalidate to mark the cache line invalid. And do all
- * this with interrupts disabled, to avoid the cache line being accidently
- * evicted while it is holding garbage.
- *
- * This also breaks in a number of circumstances:
- * - if there are modifications to the region of memory just above
- * empty_zero_page (for example because a breakpoint has been placed
- * there), then these can be lost.
- *
- * This is because the the memory address which the cache temporarily
- * caches in the above description is empty_zero_page. So the
- * movca.l hits the cache (it is assumed that it misses, or at least
- * isn't dirty), modifies the line and then invalidates it, losing the
- * required change.
- *
- * - If caches are disabled or configured in write-through mode, then
- * the movca.l writes garbage directly into memory.
- */
-static void __flush_dcache_segment_writethrough(unsigned long start,
- unsigned long extent_per_way)
-{
- unsigned long addr;
- int i;
-
- addr = CACHE_OC_ADDRESS_ARRAY | (start & cpu_data->dcache.entry_mask);
-
- while (extent_per_way) {
- for (i = 0; i < cpu_data->dcache.ways; i++)
- __raw_writel(0, addr + cpu_data->dcache.way_incr * i);
-
- addr += cpu_data->dcache.linesz;
- extent_per_way -= cpu_data->dcache.linesz;
- }
-}
-
-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);
-}
-
extern void __weak sh4__flush_region_init(void);
/*
*/
void __init sh4_cache_init(void)
{
- unsigned int wt_enabled = !!(__raw_readl(CCR) & CCR_CACHE_WT);
-
printk("PVR=%08x CVR=%08x PRR=%08x\n",
ctrl_inl(CCN_PVR),
ctrl_inl(CCN_CVR),
ctrl_inl(CCN_PRR));
- if (wt_enabled)
- __flush_dcache_segment_fn = __flush_dcache_segment_writethrough;
- else {
- 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:
- panic("unknown number of cache ways\n");
- break;
- }
- }
-
local_flush_icache_range = sh4_flush_icache_range;
local_flush_dcache_page = sh4_flush_dcache_page;
local_flush_cache_all = sh4_flush_cache_all;
git.samba.org / sfrench / cifs-2.6.git / blobdiff