diff options
Diffstat (limited to 'src/northbridge/intel/nehalem/ram_calc.c')
| -rw-r--r-- | src/northbridge/intel/nehalem/ram_calc.c | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/src/northbridge/intel/nehalem/ram_calc.c b/src/northbridge/intel/nehalem/ram_calc.c index 4d73ee9fc2..37c1ed3420 100644 --- a/src/northbridge/intel/nehalem/ram_calc.c +++ b/src/northbridge/intel/nehalem/ram_calc.c @@ -1,6 +1,7 @@ /* * This file is part of the coreboot project. * + * Copyright (C) 2012 ChromeOS Authors * Copyright (C) 2013 Vladimir Serbinenko. * * This program is free software; you can redistribute it and/or modify @@ -15,9 +16,13 @@ #define __SIMPLE_DEVICE__ +#include <arch/cpu.h> #include <arch/io.h> #include <cbmem.h> +#include <console/console.h> #include <cpu/intel/romstage.h> +#include <cpu/x86/mtrr.h> +#include <program_loading.h> #include "nehalem.h" static uintptr_t smm_region_start(void) @@ -32,7 +37,35 @@ void *cbmem_top(void) return (void *) smm_region_start(); } +#define ROMSTAGE_RAM_STACK_SIZE 0x5000 + +/* setup_stack_and_mtrrs() determines the stack to use after + * cache-as-ram is torn down as well as the MTRR settings to use. */ void *setup_stack_and_mtrrs(void) { - return (void*)CONFIG_RAMTOP; + struct postcar_frame pcf; + uintptr_t top_of_ram; + + if (postcar_frame_init(&pcf, ROMSTAGE_RAM_STACK_SIZE)) + die("Unable to initialize postcar frame.\n"); + + /* Cache the ROM as WP just below 4GiB. */ + postcar_frame_add_mtrr(&pcf, -CACHE_ROM_SIZE, CACHE_ROM_SIZE, + MTRR_TYPE_WRPROT); + + /* Cache RAM as WB from 0 -> CACHE_TMP_RAMTOP. */ + postcar_frame_add_mtrr(&pcf, 0, CACHE_TMP_RAMTOP, MTRR_TYPE_WRBACK); + + /* Cache at least 8 MiB below the top of ram, and at most 8 MiB + * above top of the ram. This satisfies MTRR alignment requirement + * with different TSEG size configurations. + */ + top_of_ram = ALIGN_DOWN((uintptr_t)cbmem_top(), 8*MiB); + postcar_frame_add_mtrr(&pcf, top_of_ram - 8*MiB, 8*MiB, MTRR_TYPE_WRBACK); + postcar_frame_add_mtrr(&pcf, top_of_ram, 8*MiB, MTRR_TYPE_WRBACK); + + /* Save the number of MTRRs to setup. Return the stack location + * pointing to the number of MTRRs. + */ + return postcar_commit_mtrrs(&pcf); } |