Arthur Heymans has uploaded this change for review.
cpu/intel/car/non-evict: Improve a few things
This improve the following:
- Improve readability for clearing fixed MTRR's
- Compute PHYSMASK high during runtime
- Cache the whole ROM_SIZE instead of XIP_ROM_SIZE
Change-Id: Ifaed96b41fab973fa541de1c4f005d6f0af5254f
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
---
M src/cpu/intel/car/non-evict/cache_as_ram.S
1 file changed, 60 insertions(+), 29 deletions(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/90/26790/1
diff --git a/src/cpu/intel/car/non-evict/cache_as_ram.S b/src/cpu/intel/car/non-evict/cache_as_ram.S
index a884479..27121d0 100644
--- a/src/cpu/intel/car/non-evict/cache_as_ram.S
+++ b/src/cpu/intel/car/non-evict/cache_as_ram.S
@@ -3,6 +3,7 @@
*
* Copyright (C) 2000,2007 Ronald G. Minnich <rminnich@gmail.com>
* Copyright (C) 2007-2008 coresystems GmbH
+ * Copyright (C) 2012 Kyösti Mälkki <kyosti.malkki@gmail.com>
*
* 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
@@ -53,18 +54,16 @@
wrmsr
post_code(0x22)
- /* Zero out all fixed 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
+ /* Clear/disable fixed MTRRs */
+ mov $fixed_mtrr_list_size, %ebx
+ xor %eax, %eax
+ xor %edx, %edx
+
+clear_fixed_mtrr:
+ add $-2, %ebx
+ movzwl fixed_mtrr_list(%ebx), %ecx
wrmsr
- add $2, %esi
- dec %edi
- jnz clear_mtrrs
+ jnz clear_fixed_mtrr
/* Zero out all variable range MTRRs. */
movl $MTRR_CAP_MSR, %ecx
@@ -81,6 +80,39 @@
dec %edi
jnz clear_var_mtrrs
+ /* Determine CPU_ADDR_BITS and load PHYSMASK high
+ * word to %edx.
+ */
+ movl $0x80000000, %eax
+ cpuid
+ cmpl $0x80000008, %eax
+ jc addrsize_no_MSR
+ movl $0x80000008, %eax
+ cpuid
+ movb %al, %cl
+ sub $32, %cl
+ movl $1, %edx
+ shl %cl, %edx
+ subl $1, %edx
+ jmp addrsize_set_high
+addrsize_no_MSR:
+ movl $1, %eax
+ cpuid
+ andl $(1 << 6 | 1 << 17), %edx /* PAE or PSE36 */
+ jz addrsize_set_high
+ movl $0x0f, %edx
+
+ /* Preload high word of address mask (in %edx) for Variable
+ * MTRRs 0 and 1 and enable local APIC at default base.
+ */
+addrsize_set_high:
+ xorl %eax, %eax
+ movl $MTRR_PHYS_MASK(0), %ecx
+ wrmsr
+ movl $MTRR_PHYS_MASK(1), %ecx
+ wrmsr
+
+
post_code(0x23)
/* Set Cache-as-RAM base address. */
movl $(MTRR_PHYS_BASE(0)), %ecx
@@ -91,8 +123,8 @@
post_code(0x24)
/* Set Cache-as-RAM mask. */
movl $(MTRR_PHYS_MASK(0)), %ecx
+ rdmsr
movl $(~(CACHE_AS_RAM_SIZE - 1) | MTRR_PHYS_MASK_VALID), %eax
- movl $CPU_PHYSMASK_HI, %edx
wrmsr
post_code(0x25)
@@ -120,7 +152,6 @@
movl $CACHE_AS_RAM_BASE, %esi
movl %esi, %edi
movl $(CACHE_AS_RAM_SIZE >> 2), %ecx
- // movl $0x23322332, %eax
xorl %eax, %eax
rep stosl
@@ -139,18 +170,12 @@
/* 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
- * https://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
+ movl $CACHE_ROM_BASE | 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
+ rdmsr
+ movl $(~(CACHE_ROM_SIZE - 1) | MTRR_PHYS_MASK_VALID), %eax
wrmsr
post_code(0x28)
@@ -181,12 +206,18 @@
hlt
jmp .Lhlt
-mtrr_table:
- /* Fixed MTRRs */
- .word 0x250, 0x258, 0x259
- .word 0x268, 0x269, 0x26A
- .word 0x26B, 0x26C, 0x26D
- .word 0x26E, 0x26F
-mtrr_table_end:
+fixed_mtrr_list:
+ .word MTRR_FIX_64K_00000
+ .word MTRR_FIX_16K_80000
+ .word MTRR_FIX_16K_A0000
+ .word MTRR_FIX_4K_C0000
+ .word MTRR_FIX_4K_C8000
+ .word MTRR_FIX_4K_D0000
+ .word MTRR_FIX_4K_D8000
+ .word MTRR_FIX_4K_E0000
+ .word MTRR_FIX_4K_E8000
+ .word MTRR_FIX_4K_F0000
+ .word MTRR_FIX_4K_F8000
+fixed_mtrr_list_size = . - fixed_mtrr_list
_cache_as_ram_setup_end:
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