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Diffstat (limited to 'arch/tile/include/uapi/arch/icache.h')
-rw-r--r-- | arch/tile/include/uapi/arch/icache.h | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/tile/include/uapi/arch/icache.h b/arch/tile/include/uapi/arch/icache.h new file mode 100644 index 0000000..762eafa --- /dev/null +++ b/arch/tile/include/uapi/arch/icache.h @@ -0,0 +1,93 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * + */ + +/** + * @file + * + * Support for invalidating bytes in the instruction cache. + */ + +#ifndef __ARCH_ICACHE_H__ +#define __ARCH_ICACHE_H__ + +#include <arch/chip.h> + + +/** + * Invalidate the instruction cache for the given range of memory. + * + * @param addr The start of memory to be invalidated. + * @param size The number of bytes to be invalidated. + * @param page_size The system's page size, e.g. getpagesize() in userspace. + * This value must be a power of two no larger than the page containing + * the code to be invalidated. If the value is smaller than the actual page + * size, this function will still work, but may run slower than necessary. + */ +static __inline void +invalidate_icache(const void* addr, unsigned long size, + unsigned long page_size) +{ + const unsigned long cache_way_size = + CHIP_L1I_CACHE_SIZE() / CHIP_L1I_ASSOC(); + unsigned long max_useful_size; + const char* start, *end; + long num_passes; + + if (__builtin_expect(size == 0, 0)) + return; + +#ifdef __tilegx__ + /* Limit the number of bytes visited to avoid redundant iterations. */ + max_useful_size = (page_size < cache_way_size) ? page_size : cache_way_size; + + /* No PA aliasing is possible, so one pass always suffices. */ + num_passes = 1; +#else + /* Limit the number of bytes visited to avoid redundant iterations. */ + max_useful_size = cache_way_size; + + /* + * Compute how many passes we need (we'll treat 0 as if it were 1). + * This works because we know the page size is a power of two. + */ + num_passes = cache_way_size >> __builtin_ctzl(page_size); +#endif + + if (__builtin_expect(size > max_useful_size, 0)) + size = max_useful_size; + + /* Locate the first and last bytes to be invalidated. */ + start = (const char *)((unsigned long)addr & -CHIP_L1I_LINE_SIZE()); + end = (const char*)addr + size - 1; + + __insn_mf(); + + do + { + const char* p; + + for (p = start; p <= end; p += CHIP_L1I_LINE_SIZE()) + __insn_icoh(p); + + start += page_size; + end += page_size; + } + while (--num_passes > 0); + + __insn_drain(); +} + + +#endif /* __ARCH_ICACHE_H__ */ |