3 files changed, 58 insertions, 5 deletions

diff --git a/src/soc/intel/common/block/include/intelblocks/meminit.h b/src/soc/intel/common/block/include/intelblocks/meminit.h
index 1fed02f5c6..130249cf71 100644
--- a/src/soc/intel/common/block/include/intelblocks/meminit.h
+++ b/src/soc/intel/common/block/include/intelblocks/meminit.h
@@ -134,11 +134,13 @@ struct mem_channel_data {
  *                 the mainboard.
  * spd_info      : Information about the memory topology.
  * half_populated: Hint from mainboard if channels are half populated.
+ * dimms_changed: True if the dimms is changed after caching the spd data.
  */
 void mem_populate_channel_data(const struct soc_mem_cfg *soc_mem_cfg,
 				const struct mem_spd *spd_info,
 				bool half_populated,
-				struct mem_channel_data *data);
+				struct mem_channel_data *data,
+				bool *dimms_changed);
 
 /*
  * Given a channel number and the maximum number of supported channels, this
diff --git a/src/soc/intel/common/block/memory/Kconfig b/src/soc/intel/common/block/memory/Kconfig
index fdcccbf742..7156be7ff6 100644
--- a/src/soc/intel/common/block/memory/Kconfig
+++ b/src/soc/intel/common/block/memory/Kconfig
@@ -28,4 +28,12 @@ config MRC_CHANNEL_WIDTH
 	  support is expected to set MRC_CHANNEL_WIDTH as per the FSP
 	  MRC expectation.
 
+config SPD_CACHE_ENABLE
+	bool
+	default n
+	help
+	  Enable to cache the spd data to the RW_SPD_CACHE region. If
+	  this option is enabled, please make sure the RW_SPD_CACHE
+	  region is added to the flash layout.
+
 endif
diff --git a/src/soc/intel/common/block/memory/meminit.c b/src/soc/intel/common/block/memory/meminit.c
index 78dc2d443a..89cd4e323e 100644
--- a/src/soc/intel/common/block/memory/meminit.c
+++ b/src/soc/intel/common/block/memory/meminit.c
@@ -5,6 +5,7 @@
 #include <intelblocks/meminit.h>
 #include <commonlib/region.h>
 #include <spd_bin.h>
+#include <spd_cache.h>
 #include <string.h>
 #include <types.h>
 
@@ -96,7 +97,7 @@ static void read_spd_md(const struct soc_mem_cfg *soc_mem_cfg, const struct mem_
 
 static bool read_spd_dimm(const struct soc_mem_cfg *soc_mem_cfg, const struct mem_spd *info,
 			bool half_populated, struct mem_channel_data *channel_data,
-			size_t *spd_len)
+			size_t *spd_len, bool *dimms_changed)
 {
 	size_t ch, dimm;
 	struct spd_block blk = { 0 };
@@ -108,6 +109,7 @@ static bool read_spd_dimm(const struct soc_mem_cfg *soc_mem_cfg, const struct me
 	 * channel is marked as populated.
 	 */
 	uint32_t pop_mask = 0;
+	*dimms_changed = false;
 
 	if (!(info->topo & MEM_TOPO_DIMM_MODULE))
 		return false;
@@ -119,7 +121,46 @@ static bool read_spd_dimm(const struct soc_mem_cfg *soc_mem_cfg, const struct me
 		}
 	}
 
-	get_spd_smbus(&blk);
+	if (CONFIG(SPD_CACHE_ENABLE)) {
+		uint8_t *spd_cache;
+		size_t spd_cache_sz;
+		bool need_update_cache = false;
+		bool dimm_changed = true;
+
+		/* load spd cache from RW_SPD_CACHE */
+		if (load_spd_cache(&spd_cache, &spd_cache_sz) == CB_SUCCESS) {
+			if (!spd_cache_is_valid(spd_cache, spd_cache_sz)) {
+				printk(BIOS_WARNING, "Invalid SPD cache\n");
+			} else {
+				dimm_changed = check_if_dimm_changed(spd_cache, &blk);
+				if (dimm_changed) {
+					/*
+					 * Set flag to indicate that the
+					 * mrc_cache need to be invalidated
+					 */
+					printk(BIOS_INFO,
+					"DIMM change, invalidate cache.\n");
+					*dimms_changed = true;
+				}
+			}
+			need_update_cache = true;
+		}
+
+		if (!dimm_changed) {
+			printk(BIOS_INFO, "Use the SPD cache data\n");
+			spd_fill_from_cache(spd_cache, &blk);
+		} else {
+			/* Access memory info through SMBUS. */
+			get_spd_smbus(&blk);
+
+			if (need_update_cache &&
+				update_spd_cache(&blk) == CB_ERR)
+				printk(BIOS_ERR, "update SPD cache failed\n");
+		}
+	} else {
+		get_spd_smbus(&blk);
+	}
+
 	*spd_len = blk.len;
 
 	for (ch = 0; ch < num_phys_ch; ch++) {
@@ -145,7 +186,8 @@ static bool read_spd_dimm(const struct soc_mem_cfg *soc_mem_cfg, const struct me
 void mem_populate_channel_data(const struct soc_mem_cfg *soc_mem_cfg,
 				const struct mem_spd *spd_info,
 				bool half_populated,
-				struct mem_channel_data *data)
+				struct mem_channel_data *data,
+				bool *dimms_changed)
 {
 	size_t spd_md_len = 0, spd_dimm_len = 0;
 	bool have_dimms;
@@ -153,7 +195,8 @@ void mem_populate_channel_data(const struct soc_mem_cfg *soc_mem_cfg,
 	memset(data, 0, sizeof(*data));
 
 	read_spd_md(soc_mem_cfg, spd_info, half_populated, data, &spd_md_len);
-	have_dimms = read_spd_dimm(soc_mem_cfg, spd_info, half_populated, data, &spd_dimm_len);
+	have_dimms = read_spd_dimm(soc_mem_cfg, spd_info, half_populated, data,
+				&spd_dimm_len, dimms_changed);
 
 	if (data->ch_population_flags == NO_CHANNEL_POPULATED)
 		die("No channels are populated. Incorrect memory configuration!\n");