diff options
Diffstat (limited to 'include/asm-xtensa/page.h')
| -rw-r--r-- | include/asm-xtensa/page.h | 106 |
1 files changed, 74 insertions, 32 deletions
diff --git a/include/asm-xtensa/page.h b/include/asm-xtensa/page.h index 1213cde75438..55ce2c9749a3 100644 --- a/include/asm-xtensa/page.h +++ b/include/asm-xtensa/page.h @@ -1,11 +1,11 @@ /* - * linux/include/asm-xtensa/page.h + * 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 - 2005 Tensilica Inc. + * Copyright (C) 2001 - 2007 Tensilica Inc. */ #ifndef _XTENSA_PAGE_H @@ -14,6 +14,12 @@ #ifdef __KERNEL__ #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 @@ -26,13 +32,60 @@ */ #define PAGE_SHIFT 12 -#define PAGE_SIZE (1 << PAGE_SHIFT) +#define PAGE_SIZE (__XTENSA_UL_CONST(1) << PAGE_SHIFT) #define PAGE_MASK (~(PAGE_SIZE-1)) #define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE - 1) & PAGE_MASK) #define PAGE_OFFSET XCHAL_KSEG_CACHED_VADDR -#define MAX_MEM_PFN XCHAL_KSEG_SIZE -#define PGTABLE_START 0x80000000 +#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__ @@ -58,34 +111,23 @@ typedef struct { unsigned long pgprot; } pgprot_t; /* * Pure 2^n version of get_order + * Use 'nsau' instructions if supported by the processor or the generic version. */ -static inline int get_order(unsigned long size) +#if XCHAL_HAVE_NSA + +static inline __attribute_const__ int get_order(unsigned long size) { - int order; -#ifndef XCHAL_HAVE_NSU - unsigned long x1, x2, x4, x8, x16; - - size = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; - x1 = size & 0xAAAAAAAA; - x2 = size & 0xCCCCCCCC; - x4 = size & 0xF0F0F0F0; - x8 = size & 0xFF00FF00; - x16 = size & 0xFFFF0000; - order = x2 ? 2 : 0; - order += (x16 != 0) * 16; - order += (x8 != 0) * 8; - order += (x4 != 0) * 4; - order += (x1 != 0); - - return order; -#else - size = (size - 1) >> PAGE_SHIFT; - asm ("nsau %0, %1" : "=r" (order) : "r" (size)); - return 32 - order; -#endif + 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); @@ -96,11 +138,11 @@ extern void copy_page(void *to, void *from); * some extra work */ -#if (DCACHE_WAY_SIZE > PAGE_SIZE) -void clear_user_page(void *addr, unsigned long vaddr, struct page* page); -void copy_user_page(void *to,void* from,unsigned long vaddr,struct page* page); +#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 clear_user_page(page, vaddr, pg) clear_page(page) # define copy_user_page(to, from, vaddr, pg) copy_page(to, from) #endif |