diff options
Diffstat (limited to 'arch/xtensa/include/asm/page.h')
| -rw-r--r-- | arch/xtensa/include/asm/page.h | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/arch/xtensa/include/asm/page.h b/arch/xtensa/include/asm/page.h new file mode 100644 index 00000000000..11f7dc2dbec --- /dev/null +++ b/arch/xtensa/include/asm/page.h @@ -0,0 +1,174 @@ +/* + * include/asm-xtensa/page.h + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version2 as + * published by the Free Software Foundation. + * + * Copyright (C) 2001 - 2007 Tensilica Inc. + */ + +#ifndef _XTENSA_PAGE_H +#define _XTENSA_PAGE_H + +#include <asm/processor.h> +#include <asm/types.h> +#include <asm/cache.h> + +/* + * Fixed TLB translations in the processor. + */ + +#define XCHAL_KSEG_CACHED_VADDR 0xd0000000 +#define XCHAL_KSEG_BYPASS_VADDR 0xd8000000 +#define XCHAL_KSEG_PADDR 0x00000000 +#define XCHAL_KSEG_SIZE 0x08000000 + +/* + * PAGE_SHIFT determines the page size + */ + +#define PAGE_SHIFT 12 +#define PAGE_SIZE (__XTENSA_UL_CONST(1) << PAGE_SHIFT) +#define PAGE_MASK (~(PAGE_SIZE-1)) + +#define PAGE_OFFSET XCHAL_KSEG_CACHED_VADDR +#define MAX_MEM_PFN XCHAL_KSEG_SIZE +#define PGTABLE_START 0x80000000 + +/* + * Cache aliasing: + * + * If the cache size for one way is greater than the page size, we have to + * deal with cache aliasing. The cache index is wider than the page size: + * + * | |cache| cache index + * | pfn |off| virtual address + * |xxxx:X|zzz| + * | : | | + * | \ / | | + * |trans.| | + * | / \ | | + * |yyyy:Y|zzz| physical address + * + * When the page number is translated to the physical page address, the lowest + * bit(s) (X) that are part of the cache index are also translated (Y). + * If this translation changes bit(s) (X), the cache index is also afected, + * thus resulting in a different cache line than before. + * The kernel does not provide a mechanism to ensure that the page color + * (represented by this bit) remains the same when allocated or when pages + * are remapped. When user pages are mapped into kernel space, the color of + * the page might also change. + * + * We use the address space VMALLOC_END ... VMALLOC_END + DCACHE_WAY_SIZE * 2 + * to temporarily map a patch so we can match the color. + */ + +#if DCACHE_WAY_SIZE > PAGE_SIZE +# define DCACHE_ALIAS_ORDER (DCACHE_WAY_SHIFT - PAGE_SHIFT) +# define DCACHE_ALIAS_MASK (PAGE_MASK & (DCACHE_WAY_SIZE - 1)) +# define DCACHE_ALIAS(a) (((a) & DCACHE_ALIAS_MASK) >> PAGE_SHIFT) +# define DCACHE_ALIAS_EQ(a,b) ((((a) ^ (b)) & DCACHE_ALIAS_MASK) == 0) +#else +# define DCACHE_ALIAS_ORDER 0 +#endif + +#if ICACHE_WAY_SIZE > PAGE_SIZE +# define ICACHE_ALIAS_ORDER (ICACHE_WAY_SHIFT - PAGE_SHIFT) +# define ICACHE_ALIAS_MASK (PAGE_MASK & (ICACHE_WAY_SIZE - 1)) +# define ICACHE_ALIAS(a) (((a) & ICACHE_ALIAS_MASK) >> PAGE_SHIFT) +# define ICACHE_ALIAS_EQ(a,b) ((((a) ^ (b)) & ICACHE_ALIAS_MASK) == 0) +#else +# define ICACHE_ALIAS_ORDER 0 +#endif + + +#ifdef __ASSEMBLY__ + +#define __pgprot(x) (x) + +#else + +/* + * These are used to make use of C type-checking.. + */ + +typedef struct { unsigned long pte; } pte_t; /* page table entry */ +typedef struct { unsigned long pgd; } pgd_t; /* PGD table entry */ +typedef struct { unsigned long pgprot; } pgprot_t; +typedef struct page *pgtable_t; + +#define pte_val(x) ((x).pte) +#define pgd_val(x) ((x).pgd) +#define pgprot_val(x) ((x).pgprot) + +#define __pte(x) ((pte_t) { (x) } ) +#define __pgd(x) ((pgd_t) { (x) } ) +#define __pgprot(x) ((pgprot_t) { (x) } ) + +/* + * Pure 2^n version of get_order + * Use 'nsau' instructions if supported by the processor or the generic version. + */ + +#if XCHAL_HAVE_NSA + +static inline __attribute_const__ int get_order(unsigned long size) +{ + int lz; + asm ("nsau %0, %1" : "=r" (lz) : "r" ((size - 1) >> PAGE_SHIFT)); + return 32 - lz; +} + +#else + +# include <asm-generic/page.h> + +#endif + +struct page; +extern void clear_page(void *page); +extern void copy_page(void *to, void *from); + +/* + * If we have cache aliasing and writeback caches, we might have to do + * some extra work + */ + +#if DCACHE_WAY_SIZE > PAGE_SIZE +extern void clear_user_page(void*, unsigned long, struct page*); +extern void copy_user_page(void*, void*, unsigned long, struct page*); +#else +# define clear_user_page(page, vaddr, pg) clear_page(page) +# define copy_user_page(to, from, vaddr, pg) copy_page(to, from) +#endif + +/* + * This handles the memory map. We handle pages at + * XCHAL_KSEG_CACHED_VADDR for kernels with 32 bit address space. + * These macros are for conversion of kernel address, not user + * addresses. + */ + +#define __pa(x) ((unsigned long) (x) - PAGE_OFFSET) +#define __va(x) ((void *)((unsigned long) (x) + PAGE_OFFSET)) +#define pfn_valid(pfn) ((unsigned long)pfn < max_mapnr) +#ifdef CONFIG_DISCONTIGMEM +# error CONFIG_DISCONTIGMEM not supported +#endif + +#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) +#define page_to_virt(page) __va(page_to_pfn(page) << PAGE_SHIFT) +#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT) +#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT) + +#define WANT_PAGE_VIRTUAL + + +#endif /* __ASSEMBLY__ */ + +#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | VM_EXEC | \ + VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) + +#include <asm-generic/memory_model.h> +#endif /* _XTENSA_PAGE_H */ |