zephyr/arch/x86/cache.c

76 lines
2.5 KiB
C

/* cache.c - cache manipulation */
/*
* Copyright (c) 2013-2014 Wind River Systems, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1) Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2) Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3) Neither the name of Wind River Systems nor the names of its contributors
* may be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
DESCRIPTION
This module contains functions for manipulation caches.
*/
#include <nanokernel.h>
#include <arch/cpu.h>
#include <misc/util.h>
#ifdef CONFIG_CLFLUSH_INSTRUCTION_SUPPORTED
#if (CONFIG_CACHE_LINE_SIZE == 0)
#error Cannot use this implementation with a cache line size of 0
#endif
/**
*
* @brief Flush a page to main memory
*
* No alignment is required for either <virt> or <size>, but since
* _SysCacheFlush() iterates on the cache lines, a cache line alignment for both
* is optimal.
*
* The cache line size is specified via the CONFIG_CACHE_LINE_SIZE kconfig
* option.
*
* @return N/A
*/
void _SysCacheFlush(VIRT_ADDR virt, size_t size)
{
int end;
size = ROUND_UP(size, CONFIG_CACHE_LINE_SIZE);
end = virt + size;
for (; virt < end; virt += CONFIG_CACHE_LINE_SIZE) {
__asm__ volatile("clflush %0;\n\t" : : "m"(virt));
}
__asm__ volatile("mfence;\n\t");
}
#endif /* CONFIG_CLFLUSH_INSTRUCTION_SUPPORTED */