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Diffstat (limited to 'src/soc/intel/common/mrc_cache.c')
-rw-r--r--src/soc/intel/common/mrc_cache.c311
1 files changed, 311 insertions, 0 deletions
diff --git a/src/soc/intel/common/mrc_cache.c b/src/soc/intel/common/mrc_cache.c
new file mode 100644
index 0000000000..8f0d18f8b3
--- /dev/null
+++ b/src/soc/intel/common/mrc_cache.c
@@ -0,0 +1,311 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2014 Google Inc.
+ *
+ * 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 <string.h>
+#include <console/console.h>
+#include <cbmem.h>
+#include <ip_checksum.h>
+#if CONFIG_CHROMEOS
+#include <vendorcode/google/chromeos/fmap.h>
+#endif
+#include "mrc_cache.h"
+
+#define MRC_DATA_ALIGN 0x1000
+#define MRC_DATA_SIGNATURE (('M'<<0)|('R'<<8)|('C'<<16)|('D'<<24))
+
+/* The mrc_data_region describes the larger non-volatile area to store
+ * mrc_saved_data objects.*/
+struct mrc_data_region {
+ void *base;
+ uint32_t size;
+};
+
+/* common code */
+static int mrc_cache_get_region(struct mrc_data_region *region)
+{
+#if CONFIG_CHROMEOS
+ int ret;
+ ret = find_fmap_entry("RW_MRC_CACHE", &region->base);
+ if (ret >= 0) {
+ region->size = ret;
+ return 0;
+ }
+#endif
+ region->base = (void *)CONFIG_MRC_SETTINGS_CACHE_BASE;
+ region->size = CONFIG_MRC_SETTINGS_CACHE_SIZE;
+ return 0;
+}
+
+static int mrc_cache_in_region(const struct mrc_data_region *region,
+ const struct mrc_saved_data *cache)
+{
+ uintptr_t region_end;
+ uintptr_t cache_end;
+
+ if ((uintptr_t)cache < (uintptr_t)region->base)
+ return 0;
+
+ region_end = (uintptr_t)region->base;
+ region_end += region->size;
+
+ if ((uintptr_t)cache >= region_end)
+ return 0;
+
+ if ((sizeof(*cache) + (uintptr_t)cache) >= region_end)
+ return 0;
+
+ cache_end = (uintptr_t)cache;
+ cache_end += cache->size + sizeof(*cache);
+
+ if (cache_end > region_end)
+ return 0;
+
+ return 1;
+}
+
+static int mrc_cache_valid(const struct mrc_data_region *region,
+ const struct mrc_saved_data *cache)
+{
+ uint32_t checksum;
+
+ if (cache->signature != MRC_DATA_SIGNATURE)
+ return 0;
+
+ if (cache->size > region->size)
+ return 0;
+
+ if (cache->reserved != 0)
+ return 0;
+
+ checksum = compute_ip_checksum((void *)&cache->data[0], cache->size);
+
+ if (cache->checksum != checksum)
+ return 0;
+
+ return 1;
+}
+
+static const struct mrc_saved_data *
+next_cache_block(const struct mrc_saved_data *cache)
+{
+ uintptr_t next = (uintptr_t)cache;
+
+ next += ALIGN(cache->size + sizeof(*cache), MRC_DATA_ALIGN);
+
+ return (const struct mrc_saved_data *)next;
+}
+
+/* Locate the most recently saved MRC data. */
+static int __mrc_cache_get_current(const struct mrc_data_region *region,
+ const struct mrc_saved_data **cache)
+{
+ const struct mrc_saved_data *msd;
+ const struct mrc_saved_data *verified_cache;
+ int slot = 0;
+
+ msd = region->base;
+
+ verified_cache = NULL;
+
+ while (mrc_cache_in_region(region, msd) &&
+ mrc_cache_valid(region, msd)) {
+ verified_cache = msd;
+ msd = next_cache_block(msd);
+ slot++;
+ }
+
+ if (verified_cache == NULL)
+ return -1;
+
+ *cache = verified_cache;
+ printk(BIOS_DEBUG, "MRC cache slot %d @ %p\n", slot-1, verified_cache);
+
+ return 0;
+}
+
+int mrc_cache_get_current(const struct mrc_saved_data **cache)
+{
+ struct mrc_data_region region;
+
+ if (mrc_cache_get_region(&region) < 0)
+ return -1;
+
+ return __mrc_cache_get_current(&region, cache);
+}
+
+#if defined(__PRE_RAM__)
+
+/*
+ * romstage code
+ */
+
+/* Fill in mrc_saved_data structure with payload. */
+static void mrc_cache_fill(struct mrc_saved_data *cache, void *data,
+ size_t size)
+{
+ cache->signature = MRC_DATA_SIGNATURE;
+ cache->size = size;
+ cache->reserved = 0;
+ memcpy(&cache->data[0], data, size);
+ cache->checksum = compute_ip_checksum((void *)&cache->data[0],
+ cache->size);
+}
+
+int mrc_cache_stash_data(void *data, size_t size)
+{
+ int cbmem_size;
+ struct mrc_saved_data *cache;
+
+ cbmem_size = sizeof(*cache) + ALIGN(size, 16);
+
+ cache = cbmem_add(CBMEM_ID_MRCDATA, cbmem_size);
+
+ if (cache == NULL) {
+ printk(BIOS_ERR, "No space in cbmem for MRC data.\n");
+ return -1;
+ }
+
+ /* Clear alignment padding bytes at end of data. */
+ memset(&cache->data[size], 0, cbmem_size - size - sizeof(*cache));
+
+ printk(BIOS_DEBUG, "Relocate MRC DATA from %p to %p (%zu bytes)\n",
+ data, cache, size);
+
+ mrc_cache_fill(cache, data, size);
+
+ return 0;
+}
+
+#else
+
+/*
+ * ramstage code
+ */
+
+#include <bootstate.h>
+#include "nvm.h"
+
+static int mrc_slot_valid(const struct mrc_data_region *region,
+ const struct mrc_saved_data *slot,
+ const struct mrc_saved_data *to_save)
+{
+ uintptr_t region_begin;
+ uintptr_t region_end;
+ uintptr_t slot_end;
+ uintptr_t slot_begin;
+ uint32_t size;
+
+ region_begin = (uintptr_t)region->base;
+ region_end = region_begin + region->size;
+ slot_begin = (uintptr_t)slot;
+ size = to_save->size + sizeof(*to_save);
+ slot_end = slot_begin + size;
+
+ if (slot_begin < region_begin || slot_begin >= region_end)
+ return 0;
+
+ if (size > region->size)
+ return 0;
+
+ if (slot_end > region_end || slot_end < region_begin)
+ return 0;
+
+ if (!nvm_is_erased(slot, size))
+ return 0;
+
+ return 1;
+}
+
+static const struct mrc_saved_data *
+mrc_cache_next_slot(const struct mrc_data_region *region,
+ const struct mrc_saved_data *current_slot)
+{
+ const struct mrc_saved_data *next_slot;
+
+ if (current_slot == NULL) {
+ next_slot = region->base;
+ } else {
+ next_slot = next_cache_block(current_slot);
+ }
+
+ return next_slot;
+}
+
+static void update_mrc_cache(void *unused)
+{
+ const struct mrc_saved_data *current_boot;
+ const struct mrc_saved_data *current_saved;
+ const struct mrc_saved_data *next_slot;
+ struct mrc_data_region region;
+
+ printk(BIOS_DEBUG, "Updating MRC cache data.\n");
+
+ current_boot = cbmem_find(CBMEM_ID_MRCDATA);
+ if (!current_boot) {
+ printk(BIOS_ERR, "No MRC cache in cbmem.\n");
+ return;
+ }
+
+ if (mrc_cache_get_region(&region)) {
+ printk(BIOS_ERR, "Could not obtain MRC cache region.\n");
+ return;
+ }
+
+ if (!mrc_cache_valid(&region, current_boot)) {
+ printk(BIOS_ERR, "MRC cache data in cbmem invalid.\n");
+ return;
+ }
+
+ current_saved = NULL;
+
+ if (!__mrc_cache_get_current(&region, &current_saved)) {
+ if (current_saved->size == current_boot->size &&
+ !memcmp(&current_saved->data[0], &current_boot->data[0],
+ current_saved->size)) {
+ printk(BIOS_DEBUG, "MRC cache up to date.\n");
+ return;
+ }
+ }
+
+ next_slot = mrc_cache_next_slot(&region, current_saved);
+
+ if (!mrc_slot_valid(&region, next_slot, current_boot)) {
+ printk(BIOS_DEBUG, "Slot @ %p is invalid.\n", next_slot);
+ if (!nvm_is_erased(region.base, region.size)) {
+ if (nvm_erase(region.base, region.size) < 0) {
+ printk(BIOS_DEBUG, "Failure erasing region.\n");
+ return;
+ }
+ }
+ next_slot = region.base;
+ }
+
+ if (nvm_write((void *)next_slot, current_boot,
+ current_boot->size + sizeof(*current_boot))) {
+ printk(BIOS_DEBUG, "Failure writing MRC cache to %p.\n",
+ next_slot);
+ }
+}
+
+BOOT_STATE_INIT_ENTRIES(mrc_cache_update) = {
+ BOOT_STATE_INIT_ENTRY(BS_WRITE_TABLES, BS_ON_ENTRY,
+ update_mrc_cache, NULL),
+};
+
+#endif /* defined(__PRE_RAM__) */
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