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path: root/src/cpu/amd/car/disable_cache_as_ram.c
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/* by yhlu 6.2005 */
/* be warned, this file will be used other cores and core 0 / node 0 */
static inline __attribute__((always_inline)) void disable_cache_as_ram(void)
{
	__asm__ __volatile__ (
	/* We don't need cache as ram for now on */
	/* disable cache */
	"movl    %%cr0, %%eax\n\t"
	"orl    $(0x1<<30),%%eax\n\t"
	"movl    %%eax, %%cr0\n\t"

	/* clear sth */
	"movl    $0x269, %%ecx\n\t"  /* fix4k_c8000*/
	"xorl    %%edx, %%edx\n\t"
	"xorl    %%eax, %%eax\n\t"
	"wrmsr\n\t"
#if CONFIG_DCACHE_RAM_SIZE > 0x8000
	"movl    $0x268, %%ecx\n\t"  /* fix4k_c0000*/
	"wrmsr\n\t"
#endif

	/* disable fixed mtrr from now on, it will be enabled by coreboot_ram again*/
	"movl    $0xC0010010, %%ecx\n\t"
//	"movl    $SYSCFG_MSR, %ecx\n\t"
	"rdmsr\n\t"
	"andl    $(~(3<<18)), %%eax\n\t"
//	"andl    $(~(SYSCFG_MSR_MtrrFixDramModEn | SYSCFG_MSR_MtrrFixDramEn)), %eax\n\t"
	"wrmsr\n\t"

	/* Set the default memory type and disable fixed and enable variable MTRRs */
	"movl    $0x2ff, %%ecx\n\t"
//	"movl    $MTRRdefType_MSR, %ecx\n\t"
	"xorl    %%edx, %%edx\n\t"
	/* Enable Variable and Disable Fixed MTRRs */
	"movl    $0x00000800, %%eax\n\t"
	"wrmsr\n\t"

	/* enable cache */
	"movl    %%cr0, %%eax\n\t"
	"andl    $0x9fffffff,%%eax\n\t"
	"movl    %%eax, %%cr0\n\t"
	::: "memory", "eax", "ecx", "edx"
	);
}

static void disable_cache_as_ram_bsp(void)
{
	disable_cache_as_ram();
}