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-rw-r--r--src/lib/Makefile.inc2
-rw-r--r--src/lib/spd_cache.c221
2 files changed, 223 insertions, 0 deletions
diff --git a/src/lib/Makefile.inc b/src/lib/Makefile.inc
index 1fed543f70..b6d318e7a3 100644
--- a/src/lib/Makefile.inc
+++ b/src/lib/Makefile.inc
@@ -345,3 +345,5 @@ spd.bin-type := spd
endif
ramstage-y += uuid.c
+
+romstage-$(CONFIG_ROMSTAGE_SPD_SMBUS) += spd_cache.c
diff --git a/src/lib/spd_cache.c b/src/lib/spd_cache.c
new file mode 100644
index 0000000000..71dfaf1024
--- /dev/null
+++ b/src/lib/spd_cache.c
@@ -0,0 +1,221 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* This file is part of the coreboot project. */
+
+#include <assert.h>
+#include <console/console.h>
+#include <crc_byte.h>
+#include <fmap.h>
+#include <spd_cache.h>
+#include <spd_bin.h>
+#include <string.h>
+
+/*
+ * SPD_CACHE layout
+ * +==========+ offset 0x00
+ * |DIMM 1 SPD| SPD data length is CONFIG_DIMM_SPD_SIZE.
+ * +----------+ offset CONFIG_DIMM_SPD_SIZE * 1
+ * |DIMM 2 SPD|
+ * +----------+ offset CONFIG_DIMM_SPD_SIZE * 2
+ * ...
+ * +----------+ offset CONFIG_DIMM_SPD_SIZE * (N -1)
+ * |DIMM N SPD| N = CONFIG_DIMM_MAX
+ * +----------+ offset CONFIG_DIMM_SPD_SIZE * CONFIG_DIMM_MAX
+ * | CRC 16 | Use to verify the data correctness.
+ * +==========+
+ *
+ * The size of the RW_SPD_CACHE needs to be aligned with 4KiB.
+ */
+
+/*
+ * Use to update SPD cache.
+ * *blk : the new SPD data will be stash into the cache.
+ *
+ * return CB_SUCCESS , update SPD cache successfully.
+ * return CB_ERR , update SPD cache unsuccessfully and the cache is invalid
+ */
+enum cb_err update_spd_cache(struct spd_block *blk)
+{
+ struct region_device rdev;
+ uint16_t data_crc = 0;
+ int i, j;
+
+ assert(blk->len <= SC_SPD_LEN);
+
+ if (fmap_locate_area_as_rdev_rw(SPD_CACHE_FMAP_NAME, &rdev)) {
+ printk(BIOS_ERR, "SPD_CACHE: Cannot access %s region\n", SPD_CACHE_FMAP_NAME);
+ return CB_ERR;
+ }
+
+ /* Erase whole area, it's for align with 4KiB which is the size of SPI rom sector. */
+ if (rdev_eraseat(&rdev, 0, region_device_sz(&rdev)) < 0) {
+ printk(BIOS_ERR, "SPD_CACHE: Cannot erase %s region\n", SPD_CACHE_FMAP_NAME);
+ return CB_ERR;
+ }
+
+ /* Write SPD data */
+ for (i = 0; i < SC_SPD_NUMS; i++) {
+ if (blk->spd_array[i] == NULL) {
+ /* If DIMM is not present, we calculate the CRC with 0xff. */
+ for (j = 0; j < SC_SPD_LEN; j++)
+ data_crc = crc16_byte(data_crc, 0xff);
+ } else {
+ if (rdev_writeat(&rdev, blk->spd_array[i], SC_SPD_OFFSET(i), blk->len)
+ < 0) {
+ printk(BIOS_ERR, "SPD_CACHE: Cannot write SPD data at %d\n",
+ SC_SPD_OFFSET(i));
+ return CB_ERR;
+ }
+
+ for (j = 0; j < blk->len; j++)
+ data_crc = crc16_byte(data_crc, blk->spd_array[i][j]);
+
+ /* If the blk->len < SC_SPD_LEN, we calculate the CRC with 0xff. */
+ if (blk->len < SC_SPD_LEN)
+ for (j = 0; j < (SC_SPD_LEN - (blk->len)); j++)
+ data_crc = crc16_byte(data_crc, 0xff);
+ }
+ }
+
+ /* Write the crc16 */
+ /* It must be the last step to ensure that the data is written correctly */
+ if (rdev_writeat(&rdev, &data_crc, SC_CRC_OFFSET, SC_CRC_LEN) < 0) {
+ printk(BIOS_ERR, "SPD_CACHE: Cannot write crc at 0x%04x\n", SC_CRC_OFFSET);
+ return CB_ERR;
+ }
+ return CB_SUCCESS;
+}
+
+/*
+ * Locate the RW_SPD_CACHE area in the fmap and read SPD_CACHE data.
+ * return CB_SUCCESS ,if the SPD_CACHE data is ready and the pointer return at *spd_cache.
+ * return CB_ERR ,if it cannot locate RW_SPD_CACHE area in the fmap or data cannot be read.
+ */
+enum cb_err load_spd_cache(uint8_t **spd_cache, size_t *spd_cache_sz)
+{
+ struct region_device rdev;
+
+ if (fmap_locate_area_as_rdev(SPD_CACHE_FMAP_NAME, &rdev) < 0) {
+ printk(BIOS_ERR, "SPD_CACHE: Cannot find %s region\n", SPD_CACHE_FMAP_NAME);
+ return CB_ERR;
+ }
+
+ /* Assume boot device is memory mapped. */
+ assert(CONFIG(BOOT_DEVICE_MEMORY_MAPPED));
+ *spd_cache = rdev_mmap_full(&rdev);
+
+ if (*spd_cache == NULL)
+ return CB_ERR;
+
+ *spd_cache_sz = region_device_sz(&rdev);
+
+ /* SPD cache found */
+ printk(BIOS_INFO, "SPD_CACHE: cache found, size 0x%zx\n", *spd_cache_sz);
+
+ return CB_SUCCESS;
+}
+
+/* Use to verify the cache data is valid. */
+bool spd_cache_is_valid(uint8_t *spd_cache, size_t spd_cache_sz)
+{
+ uint16_t data_crc = 0;
+ int i;
+
+ if (spd_cache_sz < SC_SPD_TOTAL_LEN + SC_CRC_LEN)
+ return false;
+
+ /* Check the spd_cache crc */
+ for (i = 0; i < SC_SPD_TOTAL_LEN; i++)
+ data_crc = crc16_byte(data_crc, *(spd_cache + i));
+
+ return *(uint16_t *)(spd_cache + SC_CRC_OFFSET) == data_crc;
+}
+
+/*
+ * Check if the DIMM is preset in cache.
+ * return true , DIMM is present.
+ * return false, DIMM is not present.
+ */
+static bool get_cached_dimm_present(uint8_t *spd_cache, uint8_t idx)
+{
+ if (*(uint16_t *)(spd_cache + SC_SPD_OFFSET(idx)) == 0xffff)
+ return false;
+ else
+ return true;
+}
+
+/*
+ * Use to check if the SODIMM is changed.
+ * spd_cache : it's a valid SPD cache.
+ * blk : it must include the smbus addresses of SODIMM.
+ */
+bool check_if_dimm_changed(u8 *spd_cache, struct spd_block *blk)
+{
+ int i;
+ u32 sn;
+ bool dimm_present_in_cache;
+ bool dimm_changed = false;
+ /* Check if the dimm is the same with last system boot. */
+ for (i = 0; i < SC_SPD_NUMS && dimm_changed == false; i++) {
+ /* Return true if any error happened here. */
+ if (get_spd_sn(blk->addr_map[i], &sn) == CB_ERR)
+ return true;
+ dimm_present_in_cache = get_cached_dimm_present(spd_cache, i);
+ /* Dimm is not present now. */
+ if (sn == 0xffffffff) {
+ if (dimm_present_in_cache == false)
+ printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d is not present\n", i);
+ else {
+ printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d lost\n", i);
+ dimm_changed = true;
+ }
+ } else { /* Dimm is present now. */
+ if (dimm_present_in_cache == true) {
+ if (memcmp(&sn, spd_cache + SC_SPD_OFFSET(i) + DDR4_SPD_SN_OFF,
+ SPD_SN_LEN) == 0)
+ printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d is the same\n",
+ i);
+ else {
+ printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d is new one\n",
+ i);
+ dimm_changed = true;
+ }
+ } else {
+ printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d is new one\n", i);
+ dimm_changed = true;
+ }
+ }
+ }
+ return dimm_changed;
+}
+
+/* Use to fill the struct spd_block with cache data.*/
+enum cb_err spd_fill_from_cache(uint8_t *spd_cache, struct spd_block *blk)
+{
+ int i;
+ u8 dram_type;
+
+ /* Find the first present SPD */
+ for (i = 0; i < SC_SPD_NUMS; i++)
+ if (get_cached_dimm_present(spd_cache, i) == true)
+ break;
+
+ if (i == SC_SPD_NUMS) {
+ printk(BIOS_ERR, "SPD_CACHE: No DIMM is present.\n");
+ return CB_ERR;
+ }
+
+ dram_type = *(spd_cache + SC_SPD_OFFSET(i) + SPD_DRAM_TYPE);
+
+ if (dram_type == SPD_DRAM_DDR4)
+ blk->len = SPD_PAGE_LEN_DDR4;
+ else
+ blk->len = SPD_PAGE_LEN;
+
+ for (i = 0; i < SC_SPD_NUMS; i++)
+ if (get_cached_dimm_present(spd_cache, i) == true)
+ blk->spd_array[i] = spd_cache + SC_SPD_OFFSET(i);
+ else
+ blk->spd_array[i] = NULL;
+
+ return CB_SUCCESS;
+}