From 8d802d28c23122a57d7dddf4886b0486ca183d2d Mon Sep 17 00:00:00 2001 From: Russell King Date: Tue, 10 May 2005 17:31:43 +0100 Subject: [PATCH] [PATCH] ARM: Add V6 aliasing cache flush Add cache flushing support for aliased V6 caches to flush_dcache_page. Signed-off-by: Russell King --- arch/arm/mm/flush.c | 37 +++++++++++++++++++++++++++++++++++-- 1 file changed, 35 insertions(+), 2 deletions(-) diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c index c6de48d89503..4085ed983e46 100644 --- a/arch/arm/mm/flush.c +++ b/arch/arm/mm/flush.c @@ -13,6 +13,29 @@ #include #include +#include + +#ifdef CONFIG_CPU_CACHE_VIPT +#define ALIAS_FLUSH_START 0xffff4000 + +#define TOP_PTE(x) pte_offset_kernel(top_pmd, x) + +static void flush_pfn_alias(unsigned long pfn, unsigned long vaddr) +{ + unsigned long to = ALIAS_FLUSH_START + (CACHE_COLOUR(vaddr) << PAGE_SHIFT); + + set_pte(TOP_PTE(to), pfn_pte(pfn, PAGE_KERNEL)); + flush_tlb_kernel_page(to); + + asm( "mcrr p15, 0, %1, %0, c14\n" + " mcrr p15, 0, %1, %0, c5\n" + : + : "r" (to), "r" (to + PAGE_SIZE - L1_CACHE_BYTES) + : "cc"); +} +#else +#define flush_pfn_alias(pfn,vaddr) do { } while (0) +#endif static void __flush_dcache_page(struct address_space *mapping, struct page *page) { @@ -36,6 +59,18 @@ static void __flush_dcache_page(struct address_space *mapping, struct page *page if (!mapping) return; + /* + * This is a page cache page. If we have a VIPT cache, we + * only need to do one flush - which would be at the relevant + * userspace colour, which is congruent with page->index. + */ + if (cache_is_vipt()) { + if (cache_is_vipt_aliasing()) + flush_pfn_alias(page_to_pfn(page), + page->index << PAGE_CACHE_SHIFT); + return; + } + /* * There are possible user space mappings of this page: * - VIVT cache: we need to also write back and invalidate all user @@ -57,8 +92,6 @@ static void __flush_dcache_page(struct address_space *mapping, struct page *page continue; offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT; flush_cache_page(mpnt, mpnt->vm_start + offset, page_to_pfn(page)); - if (cache_is_vipt()) - break; } flush_dcache_mmap_unlock(mapping); } -- 2.20.1