broadwell: Decouple LPDDR3 DQ/DQS maps from pei_data

Introduce the `BROADWELL_LPDDR3` Kconfig option along with some wrapper
code to allow mainboards using LPDDR3 DRAM to supply the DQ/DQS maps to
chipset code without having to use `pei_data`. The only mainboard using
LPDDR3 is Google Samus.

Change-Id: I0aaf0ace243c03600430c2a7ab6389a7b20cb432
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/55812
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/intel/broadwell/Kconfig

@@ -13,6 +13,12 @@ config SOC_SPECIFIC_OPTIONS
 	select MRC_SETTINGS_PROTECT
 	select REG_SCRIPT
 
+config BROADWELL_LPDDR3
+	bool
+	help
+	  Selected by mainboards using LPDDR3 DRAM to supply mainboard-specific
+	  LPDDR3 DQ and DQS CPU-to-DRAM mapping info needed to perform raminit.
+
 config ECAM_MMCONF_BASE_ADDRESS
 	default 0xf0000000
 

src/soc/intel/broadwell/include/soc/pei_wrapper.h

@@ -33,9 +33,17 @@ struct spd_info {
 	unsigned int spd_index;
 };
 
+struct lpddr3_dq_dqs_map {
+	uint8_t dq[2][6][2];
+	uint8_t dqs[2][8];
+};
+
 /* Mainboard callback to fill in the SPD addresses */
 void mb_get_spd_map(struct spd_info *spdi);
 
+/* Mainboard callback to retrieve the LPDDR3-specific DQ/DQS mapping */
+const struct lpddr3_dq_dqs_map *mb_get_lpddr3_dq_dqs_map(void);
+
 void broadwell_fill_pei_data(struct pei_data *pei_data);
 void mainboard_fill_pei_data(struct pei_data *pei_data);
 

src/soc/intel/broadwell/raminit.c

@@ -196,6 +196,13 @@ void perform_raminit(const struct chipset_power_state *const power_state)
 
 	mainboard_fill_pei_data(&pei_data);
 
+	if (CONFIG(BROADWELL_LPDDR3)) {
+		const struct lpddr3_dq_dqs_map *lpddr3_map = mb_get_lpddr3_dq_dqs_map();
+		assert(lpddr3_map);
+		memcpy(pei_data.dq_map, lpddr3_map->dq, sizeof(pei_data.dq_map));
+		memcpy(pei_data.dqs_map, lpddr3_map->dqs, sizeof(pei_data.dqs_map));
+	}
+
 	/* Obtain the SPD addresses from mainboard code */
 	struct spd_info spdi = { 0 };
 	mb_get_spd_map(&spdi);