zephyr/arch/x86/core/cache.c

122 lines
2.5 KiB
C

/*
* Copyright (c) 2013-2014 Wind River Systems, Inc.
* Copyright (c) 2021 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief Cache manipulation
*
* This module contains functions for manipulation caches.
*/
#include <zephyr/kernel.h>
#include <zephyr/arch/cpu.h>
#include <zephyr/sys/util.h>
#include <zephyr/toolchain.h>
#include <zephyr/cache.h>
#include <stdbool.h>
/* Not Write-through bit */
#define X86_REG_CR0_NW BIT(29)
/* Cache Disable bit */
#define X86_REG_CR0_CD BIT(30)
static inline void z_x86_wbinvd(void)
{
__asm__ volatile("wbinvd;\n\t" : : : "memory");
}
void arch_dcache_enable(void)
{
unsigned long cr0 = 0;
/* Enable write-back caching by clearing the NW and CD bits */
__asm__ volatile("mov %%cr0, %0;\n\t"
"and %1, %0;\n\t"
"mov %0, %%cr0;\n\t"
: "=r" (cr0)
: "i" (~(X86_REG_CR0_NW | X86_REG_CR0_CD)));
}
void arch_dcache_disable(void)
{
unsigned long cr0 = 0;
/* Enter the no-fill mode by setting NW=0 and CD=1 */
__asm__ volatile("mov %%cr0, %0;\n\t"
"and %1, %0;\n\t"
"or %2, %0;\n\t"
"mov %0, %%cr0;\n\t"
: "=r" (cr0)
: "i" (~(X86_REG_CR0_NW)),
"i" (X86_REG_CR0_CD));
/* Flush all caches */
z_x86_wbinvd();
}
int arch_dcache_flush_all(void)
{
z_x86_wbinvd();
return 0;
}
int arch_dcache_invd_all(void)
{
z_x86_wbinvd();
return 0;
}
int arch_dcache_flush_and_invd_all(void)
{
z_x86_wbinvd();
return 0;
}
/**
* No alignment is required for either <virt> or <size>, but since
* sys_cache_flush() iterates on the cache lines, a cache line alignment for
* both is optimal.
*
* The cache line size is specified via the d-cache-line-size DTS property.
*/
int arch_dcache_flush_range(void *start_addr, size_t size)
{
size_t line_size = sys_cache_data_line_size_get();
uintptr_t start = (uintptr_t)start_addr;
uintptr_t end = start + size;
if (line_size == 0U) {
return -ENOTSUP;
}
end = ROUND_UP(end, line_size);
for (; start < end; start += line_size) {
__asm__ volatile("clflush %0;\n\t" :
"+m"(*(volatile char *)start));
}
#if defined(CONFIG_X86_MFENCE_INSTRUCTION_SUPPORTED)
__asm__ volatile("mfence;\n\t":::"memory");
#else
__asm__ volatile("lock; addl $0,-4(%%esp);\n\t":::"memory", "cc");
#endif
return 0;
}
int arch_dcache_invd_range(void *start_addr, size_t size)
{
return arch_dcache_flush_range(start_addr, size);
}
int arch_dcache_flush_and_invd_range(void *start_addr, size_t size)
{
return arch_dcache_flush_range(start_addr, size);
}