From 6656920b0b50beacb6cb64cf55273cbb686e436e Mon Sep 17 00:00:00 2001 From: Chris Zankel Date: Wed, 22 Aug 2007 10:14:51 -0700 Subject: [XTENSA] Add support for cache-aliasing Add support for processors that have cache-aliasing issues, such as the Stretch S5000 processor. Cache-aliasing means that the size of the cache (for one way) is larger than the page size, thus, a page can end up in several places in cache depending on the virtual to physical translation. The method used here is to map a user page temporarily through the auto-refill way 0 and of of the DTLB. We probably will want to revisit this issue and use a better approach with kmap/kunmap. Signed-off-by: Chris Zankel --- include/asm-xtensa/pgtable.h | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) (limited to 'include/asm-xtensa/pgtable.h') diff --git a/include/asm-xtensa/pgtable.h b/include/asm-xtensa/pgtable.h index 667a6c46b5a1..c0fcc1c9660c 100644 --- a/include/asm-xtensa/pgtable.h +++ b/include/asm-xtensa/pgtable.h @@ -1,5 +1,5 @@ /* - * linux/include/asm-xtensa/pgtable.h + * include/asm-xtensa/pgtable.h * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -60,16 +60,20 @@ #define FIRST_USER_ADDRESS 0 #define FIRST_USER_PGD_NR (FIRST_USER_ADDRESS >> PGDIR_SHIFT) -/* virtual memory area. We keep a distance to other memory regions to be +/* + * Virtual memory area. We keep a distance to other memory regions to be * on the safe side. We also use this area for cache aliasing. */ -// FIXME: virtual memory area must be configuration-dependent - #define VMALLOC_START 0xC0000000 -#define VMALLOC_END 0xC7FF0000 +#define VMALLOC_END 0xC6FEFFFF +#define TLBTEMP_BASE_1 0xC6FF0000 +#define TLBTEMP_BASE_2 0xC6FF8000 +#define MODULE_START 0xC7000000 +#define MODULE_END 0xC7FFFFFF -/* Xtensa Linux config PTE layout (when present): +/* + * Xtensa Linux config PTE layout (when present): * 31-12: PPN * 11-6: Software * 5-4: RING @@ -126,12 +130,13 @@ #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITABLE) #define PAGE_SHARED_EXEC \ __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITABLE | _PAGE_HW_EXEC) -#define PAGE_KERNEL __pgprot(_PAGE_PRESENT) +#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_HW_WRITE) +#define PAGE_KERNEL_EXEC __pgprot(_PAGE_PRESENT|_PAGE_HW_WRITE|_PAGE_HW_EXEC) #if (DCACHE_WAY_SIZE > PAGE_SIZE) -# define _PAGE_DIRECTORY (_PAGE_VALID | _PAGE_ACCESSED | _PAGE_HW_WRITE) +# define _PAGE_DIRECTORY (_PAGE_VALID | _PAGE_ACCESSED) #else -# define _PAGE_DIRECTORY (_PAGE_VALID|_PAGE_ACCESSED|_PAGE_HW_WRITE|_PAGE_CA_WB) +# define _PAGE_DIRECTORY (_PAGE_VALID | _PAGE_ACCESSED | _PAGE_CA_WB) #endif #else /* no mmu */ @@ -244,6 +249,10 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) static inline void update_pte(pte_t *ptep, pte_t pteval) { *ptep = pteval; +#if (DCACHE_WAY_SIZE > PAGE_SIZE) && XCHAL_DCACHE_IS_WRITEBACK + __asm__ __volatile__ ("dhwb %0, 0" :: "a" (ptep)); +#endif + } struct mm_struct; @@ -383,13 +392,12 @@ extern void update_mmu_cache(struct vm_area_struct * vma, * remap a physical page `pfn' of size `size' with page protection `prot' * into virtual address `from' */ + #define io_remap_pfn_range(vma,from,pfn,size,prot) \ remap_pfn_range(vma, from, pfn, size, prot) -/* No page table caches to init */ - -#define pgtable_cache_init() do { } while (0) +extern void pgtable_cache_init(void); typedef pte_t *pte_addr_t; -- cgit v1.2.3