diff options
author | Simon Glass <sjg@chromium.org> | 2015-09-02 17:24:58 -0600 |
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committer | Tom Rini <trini@konsulko.com> | 2015-09-11 17:15:20 -0400 |
commit | cf92e05c0135bc2b1a1b25a3218e31e6d79bad59 (patch) | |
tree | 0ccaa4c6fb0edf61e473c58cfcba827c65d9ae15 /include | |
parent | 6e295186c7fc8bf5be22a05f6ca9602f2bb507f2 (diff) | |
download | u-boot-cf92e05c0135bc2b1a1b25a3218e31e6d79bad59.tar.gz |
Move ALLOC_CACHE_ALIGN_BUFFER() to the new memalign.h header
Now that we have a new header file for cache-aligned allocation, we should
move the stack-based allocation macro there also.
Signed-off-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/common.h | 87 | ||||
-rw-r--r-- | include/memalign.h | 93 |
2 files changed, 92 insertions, 88 deletions
diff --git a/include/common.h b/include/common.h index c48e5bc11bf..68b24d0778d 100644 --- a/include/common.h +++ b/include/common.h @@ -974,93 +974,6 @@ int cpu_release(int nr, int argc, char * const argv[]); #define ROUND(a,b) (((a) + (b) - 1) & ~((b) - 1)) /* - * ARCH_DMA_MINALIGN is defined in asm/cache.h for each architecture. It - * is used to align DMA buffers. - */ -#ifndef __ASSEMBLY__ -#include <asm/cache.h> -#endif - -/* - * The ALLOC_CACHE_ALIGN_BUFFER macro is used to allocate a buffer on the - * stack that meets the minimum architecture alignment requirements for DMA. - * Such a buffer is useful for DMA operations where flushing and invalidating - * the cache before and after a read and/or write operation is required for - * correct operations. - * - * When called the macro creates an array on the stack that is sized such - * that: - * - * 1) The beginning of the array can be advanced enough to be aligned. - * - * 2) The size of the aligned portion of the array is a multiple of the minimum - * architecture alignment required for DMA. - * - * 3) The aligned portion contains enough space for the original number of - * elements requested. - * - * The macro then creates a pointer to the aligned portion of this array and - * assigns to the pointer the address of the first element in the aligned - * portion of the array. - * - * Calling the macro as: - * - * ALLOC_CACHE_ALIGN_BUFFER(uint32_t, buffer, 1024); - * - * Will result in something similar to saying: - * - * uint32_t buffer[1024]; - * - * The following differences exist: - * - * 1) The resulting buffer is guaranteed to be aligned to the value of - * ARCH_DMA_MINALIGN. - * - * 2) The buffer variable created by the macro is a pointer to the specified - * type, and NOT an array of the specified type. This can be very important - * if you want the address of the buffer, which you probably do, to pass it - * to the DMA hardware. The value of &buffer is different in the two cases. - * In the macro case it will be the address of the pointer, not the address - * of the space reserved for the buffer. However, in the second case it - * would be the address of the buffer. So if you are replacing hard coded - * stack buffers with this macro you need to make sure you remove the & from - * the locations where you are taking the address of the buffer. - * - * Note that the size parameter is the number of array elements to allocate, - * not the number of bytes. - * - * This macro can not be used outside of function scope, or for the creation - * of a function scoped static buffer. It can not be used to create a cache - * line aligned global buffer. - */ -#define PAD_COUNT(s, pad) (((s) - 1) / (pad) + 1) -#define PAD_SIZE(s, pad) (PAD_COUNT(s, pad) * pad) -#define ALLOC_ALIGN_BUFFER_PAD(type, name, size, align, pad) \ - char __##name[ROUND(PAD_SIZE((size) * sizeof(type), pad), align) \ - + (align - 1)]; \ - \ - type *name = (type *) ALIGN((uintptr_t)__##name, align) -#define ALLOC_ALIGN_BUFFER(type, name, size, align) \ - ALLOC_ALIGN_BUFFER_PAD(type, name, size, align, 1) -#define ALLOC_CACHE_ALIGN_BUFFER_PAD(type, name, size, pad) \ - ALLOC_ALIGN_BUFFER_PAD(type, name, size, ARCH_DMA_MINALIGN, pad) -#define ALLOC_CACHE_ALIGN_BUFFER(type, name, size) \ - ALLOC_ALIGN_BUFFER(type, name, size, ARCH_DMA_MINALIGN) - -/* - * DEFINE_CACHE_ALIGN_BUFFER() is similar to ALLOC_CACHE_ALIGN_BUFFER, but it's - * purpose is to allow allocating aligned buffers outside of function scope. - * Usage of this macro shall be avoided or used with extreme care! - */ -#define DEFINE_ALIGN_BUFFER(type, name, size, align) \ - static char __##name[ALIGN(size * sizeof(type), align)] \ - __aligned(align); \ - \ - static type *name = (type *)__##name -#define DEFINE_CACHE_ALIGN_BUFFER(type, name, size) \ - DEFINE_ALIGN_BUFFER(type, name, size, ARCH_DMA_MINALIGN) - -/* * check_member() - Check the offset of a structure member * * @structure: Name of structure (e.g. global_data) diff --git a/include/memalign.h b/include/memalign.h index f78b9dd9dc7..a9600390839 100644 --- a/include/memalign.h +++ b/include/memalign.h @@ -13,9 +13,100 @@ */ #ifndef __ASSEMBLY__ #include <asm/cache.h> - #include <malloc.h> +/* + * The ALLOC_CACHE_ALIGN_BUFFER macro is used to allocate a buffer on the + * stack that meets the minimum architecture alignment requirements for DMA. + * Such a buffer is useful for DMA operations where flushing and invalidating + * the cache before and after a read and/or write operation is required for + * correct operations. + * + * When called the macro creates an array on the stack that is sized such + * that: + * + * 1) The beginning of the array can be advanced enough to be aligned. + * + * 2) The size of the aligned portion of the array is a multiple of the minimum + * architecture alignment required for DMA. + * + * 3) The aligned portion contains enough space for the original number of + * elements requested. + * + * The macro then creates a pointer to the aligned portion of this array and + * assigns to the pointer the address of the first element in the aligned + * portion of the array. + * + * Calling the macro as: + * + * ALLOC_CACHE_ALIGN_BUFFER(uint32_t, buffer, 1024); + * + * Will result in something similar to saying: + * + * uint32_t buffer[1024]; + * + * The following differences exist: + * + * 1) The resulting buffer is guaranteed to be aligned to the value of + * ARCH_DMA_MINALIGN. + * + * 2) The buffer variable created by the macro is a pointer to the specified + * type, and NOT an array of the specified type. This can be very important + * if you want the address of the buffer, which you probably do, to pass it + * to the DMA hardware. The value of &buffer is different in the two cases. + * In the macro case it will be the address of the pointer, not the address + * of the space reserved for the buffer. However, in the second case it + * would be the address of the buffer. So if you are replacing hard coded + * stack buffers with this macro you need to make sure you remove the & from + * the locations where you are taking the address of the buffer. + * + * Note that the size parameter is the number of array elements to allocate, + * not the number of bytes. + * + * This macro can not be used outside of function scope, or for the creation + * of a function scoped static buffer. It can not be used to create a cache + * line aligned global buffer. + */ +#define PAD_COUNT(s, pad) (((s) - 1) / (pad) + 1) +#define PAD_SIZE(s, pad) (PAD_COUNT(s, pad) * pad) +#define ALLOC_ALIGN_BUFFER_PAD(type, name, size, align, pad) \ + char __##name[ROUND(PAD_SIZE((size) * sizeof(type), pad), align) \ + + (align - 1)]; \ + \ + type *name = (type *)ALIGN((uintptr_t)__##name, align) +#define ALLOC_ALIGN_BUFFER(type, name, size, align) \ + ALLOC_ALIGN_BUFFER_PAD(type, name, size, align, 1) +#define ALLOC_CACHE_ALIGN_BUFFER_PAD(type, name, size, pad) \ + ALLOC_ALIGN_BUFFER_PAD(type, name, size, ARCH_DMA_MINALIGN, pad) +#define ALLOC_CACHE_ALIGN_BUFFER(type, name, size) \ + ALLOC_ALIGN_BUFFER(type, name, size, ARCH_DMA_MINALIGN) + +/* + * DEFINE_CACHE_ALIGN_BUFFER() is similar to ALLOC_CACHE_ALIGN_BUFFER, but it's + * purpose is to allow allocating aligned buffers outside of function scope. + * Usage of this macro shall be avoided or used with extreme care! + */ +#define DEFINE_ALIGN_BUFFER(type, name, size, align) \ + static char __##name[ALIGN(size * sizeof(type), align)] \ + __aligned(align); \ + \ + static type *name = (type *)__##name +#define DEFINE_CACHE_ALIGN_BUFFER(type, name, size) \ + DEFINE_ALIGN_BUFFER(type, name, size, ARCH_DMA_MINALIGN) + +/** + * malloc_cache_aligned() - allocate a memory region aligned to cache line size + * + * This allocates memory at a cache-line boundary. The amount allocated may + * be larger than requested as it is rounded up to the nearest multiple of the + * cache-line size. This ensured that subsequent cache operations on this + * memory (flush, invalidate) will not affect subsequently allocated regions. + * + * @size: Minimum number of bytes to allocate + * + * @return pointer to new memory region, or NULL if there is no more memory + * available. + */ static inline void *malloc_cache_aligned(size_t size) { return memalign(ARCH_DMA_MINALIGN, ALIGN(size, ARCH_DMA_MINALIGN)); |