From deaef20e9789d93c06d2d3b5ffc99939814802ca Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Wed, 9 Sep 2009 16:06:39 +0900 Subject: [PATCH] sh: Rework sh4_flush_cache_page() for coherent kmap mapping. This builds on top of the MIPS r4k code that does roughly the same thing. This permits the use of kmap_coherent() for mapped pages with dirty dcache lines and falls back on kmap_atomic() otherwise. This also fixes up a problem with the alias check and defers to shm_align_mask directly. Signed-off-by: Paul Mundt --- arch/sh/mm/cache-sh4.c | 75 +++++++++++++++++++++++++++--------------- 1 file changed, 48 insertions(+), 27 deletions(-) diff --git a/arch/sh/mm/cache-sh4.c b/arch/sh/mm/cache-sh4.c index 92b7d947db9..e3fbd99b323 100644 --- a/arch/sh/mm/cache-sh4.c +++ b/arch/sh/mm/cache-sh4.c @@ -2,7 +2,7 @@ * 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. * @@ -15,6 +15,8 @@ #include #include #include +#include +#include #include #include @@ -23,7 +25,6 @@ * 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_4096(unsigned long addr, unsigned long phys, @@ -209,44 +210,64 @@ static void sh4_flush_cache_page(void *args) { 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; 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; + address &= PAGE_MASK; + pgd = pgd_offset(vma->vm_mm, address); + pud = pud_offset(pgd, address); + pmd = pmd_offset(pud, address); + pte = pte_offset_kernel(pmd, address); - /* 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); + /* If the page isn't present, there is nothing to do here. */ + if (!(pte_val(*pte) & _PAGE_PRESENT)) + return; + + if ((vma->vm_mm == current->active_mm)) + vaddr = NULL; + else { + /* + * Use kmap_coherent or kmap_atomic to do flushes for + * another ASID than the current one. + */ + 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; } - 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); + if (pages_do_alias(address, phys)) + flush_cache_4096(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); } }