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/*
* This file is part of the coreboot project.
*
* Copyright (C) 2000,2007 Ronald G. Minnich <rminnich@gmail.com>
* Copyright (C) 2007-2008 coresystems GmbH
*
* 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 of the License.
*
* 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. See the
* GNU General Public License for more details.
*/
#include <cpu/x86/mtrr.h>
#include <cpu/x86/cache.h>
#include <cpu/x86/post_code.h>
#define CPU_PHYSMASK_HI (1 << (CONFIG_CPU_ADDR_BITS - 32) - 1)
#define CACHE_AS_RAM_SIZE CONFIG_DCACHE_RAM_SIZE
#define CACHE_AS_RAM_BASE CONFIG_DCACHE_RAM_BASE
/* Save the BIST result. */
movl %eax, %ebp
cache_as_ram:
post_code(0x20)
/* Send INIT IPI to all excluding ourself. */
movl $0x000C4500, %eax
movl $0xFEE00300, %esi
movl %eax, (%esi)
/* Zero out all fixed range and variable range MTRRs. */
movl $mtrr_table, %esi
movl $((mtrr_table_end - mtrr_table) >> 1), %edi
xorl %eax, %eax
xorl %edx, %edx
clear_mtrrs:
movw (%esi), %bx
movzx %bx, %ecx
wrmsr
add $2, %esi
dec %edi
jnz clear_mtrrs
post_code(0x22)
/* Configure the default memory type to uncacheable. */
movl $MTRR_DEF_TYPE_MSR, %ecx
rdmsr
andl $(~0x00000cff), %eax
wrmsr
post_code(0x23)
/* Set Cache-as-RAM base address. */
movl $(MTRR_PHYS_BASE(0)), %ecx
movl $(CACHE_AS_RAM_BASE | MTRR_TYPE_WRBACK), %eax
xorl %edx, %edx
wrmsr
post_code(0x24)
/* Set Cache-as-RAM mask. */
movl $(MTRR_PHYS_MASK(0)), %ecx
movl $(~(CACHE_AS_RAM_SIZE - 1) | MTRR_PHYS_MASK_VALID), %eax
movl $CPU_PHYSMASK_HI, %edx
wrmsr
post_code(0x25)
/* Enable MTRR. */
movl $MTRR_DEF_TYPE_MSR, %ecx
rdmsr
orl $MTRR_DEF_TYPE_EN, %eax
wrmsr
/* Enable L2 cache. */
movl $0x11e, %ecx
rdmsr
orl $(1 << 8), %eax
wrmsr
/* Enable cache (CR0.CD = 0, CR0.NW = 0). */
movl %cr0, %eax
andl $(~(CR0_CacheDisable | CR0_NoWriteThrough)), %eax
invd
movl %eax, %cr0
/* Clear the cache memory region. This will also fill up the cache. */
movl $CACHE_AS_RAM_BASE, %esi
movl %esi, %edi
movl $(CACHE_AS_RAM_SIZE >> 2), %ecx
// movl $0x23322332, %eax
xorl %eax, %eax
rep stosl
post_code(0x26)
/* Enable Cache-as-RAM mode by disabling cache. */
movl %cr0, %eax
orl $CR0_CacheDisable, %eax
movl %eax, %cr0
/* Enable cache for our code in Flash because we do XIP here */
movl $MTRR_PHYS_BASE(1), %ecx
xorl %edx, %edx
/*
* IMPORTANT: The following calculation _must_ be done at runtime. See
* http://www.coreboot.org/pipermail/coreboot/2010-October/060855.html
*/
movl $copy_and_run, %eax
andl $(~(CONFIG_XIP_ROM_SIZE - 1)), %eax
orl $MTRR_TYPE_WRPROT, %eax
wrmsr
movl $MTRR_PHYS_MASK(1), %ecx
movl $CPU_PHYSMASK_HI, %edx
movl $(~(CONFIG_XIP_ROM_SIZE - 1) | MTRR_PHYS_MASK_VALID), %eax
wrmsr
post_code(0x28)
/* Enable cache. */
movl %cr0, %eax
andl $(~(CR0_CacheDisable | CR0_NoWriteThrough)), %eax
movl %eax, %cr0
/* Set up the stack pointer. */
movl $(CACHE_AS_RAM_BASE + CACHE_AS_RAM_SIZE - 4), %eax
movl %eax, %esp
/* Restore the BIST result. */
movl %ebp, %eax
movl %esp, %ebp
pushl %eax
before_romstage:
post_code(0x29)
/* Call romstage.c main function. */
call romstage_main
/* Save return value from romstage_main. It contains the stack to use
* after cache-as-ram is torn down.
*/
movl %eax, %ebx
post_code(0x30)
/* Disable cache. */
movl %cr0, %eax
orl $CR0_CacheDisable, %eax
movl %eax, %cr0
post_code(0x31)
/* Disable MTRR. */
movl $MTRR_DEF_TYPE_MSR, %ecx
rdmsr
andl $(~MTRR_DEF_TYPE_EN), %eax
wrmsr
post_code(0x32)
invd
post_code(0x33)
/* Enable cache. */
movl %cr0, %eax
andl $~(CR0_CacheDisable | CR0_NoWriteThrough), %eax
movl %eax, %cr0
post_code(0x36)
/* Disable cache. */
movl %cr0, %eax
orl $CR0_CacheDisable, %eax
movl %eax, %cr0
post_code(0x38)
/* Enable Write Back and Speculative Reads for low RAM. */
movl $MTRR_PHYS_BASE(0), %ecx
movl $(0x00000000 | MTRR_TYPE_WRBACK), %eax
xorl %edx, %edx
wrmsr
movl $MTRR_PHYS_MASK(0), %ecx
movl $(~(CACHE_TMP_RAMTOP - 1) | MTRR_PHYS_MASK_VALID), %eax
movl $CPU_PHYSMASK_HI, %edx
wrmsr
#if CACHE_ROM_SIZE
/* Enable caching and Speculative Reads for Flash ROM device. */
movl $MTRR_PHYS_BASE(1), %ecx
movl $(CACHE_ROM_BASE | MTRR_TYPE_WRPROT), %eax
xorl %edx, %edx
wrmsr
movl $MTRR_PHYS_MASK(1), %ecx
movl $(~(CACHE_ROM_SIZE - 1) | MTRR_PHYS_MASK_VALID), %eax
movl $CPU_PHYSMASK_HI, %edx
wrmsr
#endif
post_code(0x39)
/* And enable cache again after setting MTRRs. */
movl %cr0, %eax
andl $~(CR0_CacheDisable | CR0_NoWriteThrough), %eax
movl %eax, %cr0
post_code(0x3a)
/* Enable MTRR. */
movl $MTRR_DEF_TYPE_MSR, %ecx
rdmsr
orl $MTRR_DEF_TYPE_EN, %eax
wrmsr
post_code(0x3b)
/* Invalidate the cache again. */
invd
post_code(0x3c)
__main:
post_code(POST_PREPARE_RAMSTAGE)
cld /* Clear direction flag. */
/* Setup stack as indicated by return value from romstage_main(). */
movl %ebx, %esp
movl %esp, %ebp
call copy_and_run
.Lhlt:
post_code(POST_DEAD_CODE)
hlt
jmp .Lhlt
mtrr_table:
/* Fixed MTRRs */
.word 0x250, 0x258, 0x259
.word 0x268, 0x269, 0x26A
.word 0x26B, 0x26C, 0x26D
.word 0x26E, 0x26F
/* Variable MTRRs */
.word 0x200, 0x201, 0x202, 0x203
.word 0x204, 0x205, 0x206, 0x207
.word 0x208, 0x209, 0x20A, 0x20B
.word 0x20C, 0x20D, 0x20E, 0x20F
mtrr_table_end:
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