coreboot-kgpe-d16/src/lib/cbmem.c
Aaron Durbin 716738a6b8 x86: add cache-as-ram migration option
There are some boards that do a significant amount of
work after cache-as-ram is torn down but before ramstage
is loaded. For example, using vboot to verify the ramstage
is one such operation. However, there are pieces of code
that are executed that reference global variables that
are linked in the cache-as-ram region. If those variables
are referenced after cache-as-ram is torn down then the
values observed will most likely be incorrect.

Therefore provide a Kconfig option to select cache-as-ram
migration to memory using cbmem. This option is named
CAR_MIGRATION. When enabled, the address of cache-as-ram
variables may be obtained dynamically. Additionally,
when cache-as-ram migration occurs the cache-as-ram
data region for global variables is copied into cbmem.
There are also automatic callbacks for other modules
to perform their own migration, if necessary.

Change-Id: I2e77219647c2bd2b1aa845b262be3b2543f1fcb7
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/3232
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2013-05-16 01:29:50 +02:00

272 lines
6.4 KiB
C

/*
* This file is part of the coreboot project.
*
* Copyright (C) 2009 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
*/
#include <types.h>
#include <string.h>
#include <bootstate.h>
#include <cbmem.h>
#include <console/console.h>
#include <cpu/x86/car.h>
#if CONFIG_HAVE_ACPI_RESUME && !defined(__PRE_RAM__)
#include <arch/acpi.h>
#endif
// The CBMEM TOC reserves 512 bytes to keep
// the other entries somewhat aligned.
// Increase if MAX_CBMEM_ENTRIES exceeds 21
#define CBMEM_TOC_RESERVED 512
#define MAX_CBMEM_ENTRIES 16
#define CBMEM_MAGIC 0x434f5245
struct cbmem_entry {
u32 magic;
u32 id;
u64 base;
u64 size;
} __attribute__((packed));
#ifndef __PRE_RAM__
static struct cbmem_entry *bss_cbmem_toc;
struct cbmem_entry *__attribute__((weak)) get_cbmem_toc(void)
{
return bss_cbmem_toc;
}
void __attribute__((weak)) set_cbmem_toc(struct cbmem_entry * x)
{
/* do nothing, this should be called by chipset to save TOC in NVRAM */
}
#else
struct cbmem_entry *__attribute__((weak)) get_cbmem_toc(void)
{
printk(BIOS_WARNING, "WARNING: you need to define get_cbmem_toc() for your chipset\n");
return NULL;
}
#endif
/**
* cbmem is a simple mechanism to do some kind of book keeping of the coreboot
* high tables memory. This is a small amount of memory which is "stolen" from
* the system memory for coreboot purposes. Usually this memory is used for
* - the coreboot table
* - legacy tables (PIRQ, MP table)
* - ACPI tables
* - suspend/resume backup memory
*/
void cbmem_init(u64 baseaddr, u64 size)
{
struct cbmem_entry *cbmem_toc;
cbmem_toc = (struct cbmem_entry *)(unsigned long)baseaddr;
#ifndef __PRE_RAM__
bss_cbmem_toc = cbmem_toc;
#endif
printk(BIOS_DEBUG, "Initializing CBMEM area to 0x%llx (%lld bytes)\n",
baseaddr, size);
if (size < (64 * 1024)) {
printk(BIOS_DEBUG, "Increase CBMEM size!\n");
for (;;) ;
}
/* we don't need to call this in romstage, usefull only from ramstage */
#ifndef __PRE_RAM__
set_cbmem_toc((struct cbmem_entry *)(unsigned long)baseaddr);
#endif
memset(cbmem_toc, 0, CBMEM_TOC_RESERVED);
cbmem_toc[0] = (struct cbmem_entry) {
.magic = CBMEM_MAGIC,
.id = CBMEM_ID_FREESPACE,
.base = baseaddr + CBMEM_TOC_RESERVED,
.size = size - CBMEM_TOC_RESERVED
};
}
int cbmem_reinit(u64 baseaddr)
{
struct cbmem_entry *cbmem_toc;
cbmem_toc = (struct cbmem_entry *)(unsigned long)baseaddr;
printk(BIOS_DEBUG, "Re-Initializing CBMEM area to 0x%lx\n",
(unsigned long)baseaddr);
#ifndef __PRE_RAM__
bss_cbmem_toc = cbmem_toc;
#endif
return (cbmem_toc[0].magic == CBMEM_MAGIC);
}
void *cbmem_add(u32 id, u64 size)
{
struct cbmem_entry *cbmem_toc;
int i;
void *p;
/*
* This could be a restart, check if the section is there already. It
* is remotely possible that the dram contents persisted over the
* bootloader upgrade AND the same section now needs more room, but
* this is quite a remote possibility and it is ignored here.
*/
p = cbmem_find(id);
if (p) {
printk(BIOS_NOTICE,
"CBMEM section %x: using existing location at %p.\n",
id, p);
return p;
}
cbmem_toc = get_cbmem_toc();
if (cbmem_toc == NULL) {
return NULL;
}
if (cbmem_toc[0].magic != CBMEM_MAGIC) {
printk(BIOS_ERR, "ERROR: CBMEM was not initialized yet.\n");
return NULL;
}
/* Will the entry fit at all? */
if (size > cbmem_toc[0].size) {
printk(BIOS_ERR, "ERROR: Not enough memory for table %x\n", id);
return NULL;
}
/* Align size to 512 byte blocks */
size = ALIGN(size, 512) < cbmem_toc[0].size ?
ALIGN(size, 512) : cbmem_toc[0].size;
/* Now look for the first free/usable TOC entry */
for (i = 0; i < MAX_CBMEM_ENTRIES; i++) {
if (cbmem_toc[i].id == CBMEM_ID_NONE)
break;
}
if (i >= MAX_CBMEM_ENTRIES) {
printk(BIOS_ERR, "ERROR: No more CBMEM entries available.\n");
return NULL;
}
printk(BIOS_DEBUG, "Adding CBMEM entry as no. %d\n", i);
cbmem_toc[i] = (struct cbmem_entry) {
.magic = CBMEM_MAGIC,
.id = id,
.base = cbmem_toc[0].base,
.size = size
};
cbmem_toc[0].base += size;
cbmem_toc[0].size -= size;
return (void *)(u32)cbmem_toc[i].base;
}
void *cbmem_find(u32 id)
{
struct cbmem_entry *cbmem_toc;
int i;
cbmem_toc = get_cbmem_toc();
if (cbmem_toc == NULL)
return NULL;
for (i = 0; i < MAX_CBMEM_ENTRIES; i++) {
if (cbmem_toc[i].id == id)
return (void *)(unsigned long)cbmem_toc[i].base;
}
return (void *)NULL;
}
#if CONFIG_EARLY_CBMEM_INIT || !defined(__PRE_RAM__)
/* Returns True if it was not intialized before. */
int cbmem_initialize(void)
{
int rv = 0;
#ifdef __PRE_RAM__
extern unsigned long get_top_of_ram(void);
uint64_t high_tables_base = get_top_of_ram() - HIGH_MEMORY_SIZE;
uint64_t high_tables_size = HIGH_MEMORY_SIZE;
#endif
/* We expect the romstage to always initialize it. */
if (!cbmem_reinit(high_tables_base)) {
#if CONFIG_HAVE_ACPI_RESUME && !defined(__PRE_RAM__)
/* Something went wrong, our high memory area got wiped */
if (acpi_slp_type == 3 || acpi_slp_type == 2)
acpi_slp_type = 0;
#endif
cbmem_init(high_tables_base, high_tables_size);
rv = 1;
}
#ifndef __PRE_RAM__
cbmem_arch_init();
#endif
/* Migrate cache-as-ram variables. */
car_migrate_variables();
return rv;
}
#endif
#ifndef __PRE_RAM__
static void init_cbmem_post_device(void *unused)
{
cbmem_initialize();
#if CONFIG_CONSOLE_CBMEM
cbmemc_reinit();
#endif
}
BOOT_STATE_INIT_ENTRIES(cbmem_bscb) = {
BOOT_STATE_INIT_ENTRY(BS_POST_DEVICE, BS_ON_ENTRY,
init_cbmem_post_device, NULL),
};
void cbmem_list(void)
{
struct cbmem_entry *cbmem_toc;
int i;
cbmem_toc = get_cbmem_toc();
if (cbmem_toc == NULL)
return;
for (i = 0; i < MAX_CBMEM_ENTRIES; i++) {
if (cbmem_toc[i].magic != CBMEM_MAGIC)
continue;
cbmem_print_entry(i, cbmem_toc[i].id, cbmem_toc[i].base,
cbmem_toc[i].size);
}
}
#endif