[ARM] 3356/1: Workaround for the ARM1136 I-cache invalidation problem

Patch from Catalin Marinas

ARM1136 erratum 371025 (category 2) specifies that, under rare
conditions, an invalidate I-cache by MVA (line or range) operation can
fail to invalidate a cache line. The recommended workaround is to
either invalidate the entire I-cache or invalidate the range by
set/way rather than MVA.

Note that for a 16K cache size, invalidating a 4K page by set/way is
equivalent to invalidating the entire I-cache.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Catalin Marinas 2006-03-10 22:26:47 +00:00 committed by Russell King
parent e7fcdb79ec
commit 141fa40cff
2 changed files with 8 additions and 5 deletions

View File

@ -96,15 +96,16 @@ ENTRY(v6_coherent_user_range)
#ifdef HARVARD_CACHE #ifdef HARVARD_CACHE
bic r0, r0, #CACHE_LINE_SIZE - 1 bic r0, r0, #CACHE_LINE_SIZE - 1
1: mcr p15, 0, r0, c7, c10, 1 @ clean D line 1: mcr p15, 0, r0, c7, c10, 1 @ clean D line
mcr p15, 0, r0, c7, c5, 1 @ invalidate I line
add r0, r0, #CACHE_LINE_SIZE add r0, r0, #CACHE_LINE_SIZE
cmp r0, r1 cmp r0, r1
blo 1b blo 1b
#endif #endif
mcr p15, 0, r0, c7, c5, 6 @ invalidate BTB
#ifdef HARVARD_CACHE
mov r0, #0 mov r0, #0
#ifdef HARVARD_CACHE
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
mcr p15, 0, r0, c7, c5, 0 @ I+BTB cache invalidate
#else
mcr p15, 0, r0, c7, c5, 6 @ invalidate BTB
#endif #endif
mov pc, lr mov pc, lr

View File

@ -24,14 +24,16 @@
static void flush_pfn_alias(unsigned long pfn, unsigned long vaddr) static void flush_pfn_alias(unsigned long pfn, unsigned long vaddr)
{ {
unsigned long to = ALIAS_FLUSH_START + (CACHE_COLOUR(vaddr) << PAGE_SHIFT); unsigned long to = ALIAS_FLUSH_START + (CACHE_COLOUR(vaddr) << PAGE_SHIFT);
const int zero = 0;
set_pte(TOP_PTE(to), pfn_pte(pfn, PAGE_KERNEL)); set_pte(TOP_PTE(to), pfn_pte(pfn, PAGE_KERNEL));
flush_tlb_kernel_page(to); flush_tlb_kernel_page(to);
asm( "mcrr p15, 0, %1, %0, c14\n" asm( "mcrr p15, 0, %1, %0, c14\n"
" mcrr p15, 0, %1, %0, c5\n" " mcr p15, 0, %2, c7, c10, 4\n"
" mcr p15, 0, %2, c7, c5, 0\n"
: :
: "r" (to), "r" (to + PAGE_SIZE - L1_CACHE_BYTES) : "r" (to), "r" (to + PAGE_SIZE - L1_CACHE_BYTES), "r" (zero)
: "cc"); : "cc");
} }