soc/intel/tigerlake: Reorganize memory initialization support

This change reorganizes memory initialization code for LPDDR4x on
TGL to allow sharing of code when adding support for other memory
types. In follow-up changes, support for DDR4 will be added.

1. It adds configuration for memory topology which is currently only
MEMORY_DOWN, however DDR4 requires more topologies to be
supported.
2. spd_info structure is organized to allow mixed topologies as well.
3. DQ/DQS maps are organized to reflect hardware configuration.

TEST=Verified that volteer still boots and memory initialization is
successful.

Signed-off-by: Furquan Shaikh <furquan@google.com>
Change-Id: Ib625f2ab30a6e1362a310d9abb3f2051f85c3013
Reviewed-on: https://review.coreboot.org/c/coreboot/+/39865
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: EricR Lai <ericr_lai@compal.corp-partner.google.com>

2 files changed, 282 insertions, 139 deletions

diff --git a/src/soc/intel/tigerlake/include/soc/meminit.h b/src/soc/intel/tigerlake/include/soc/meminit.h
index 2345b2b12d..aab155e43c 100644
--- a/src/soc/intel/tigerlake/include/soc/meminit.h
+++ b/src/soc/intel/tigerlake/include/soc/meminit.h
@@ -12,46 +12,65 @@
 #include <stdint.h>
 #include <fsp/soc_binding.h>
 
-#define BYTES_PER_CHANNEL	2
-#define BITS_PER_BYTE		8
-#define DQS_PER_CHANNEL		2
-#define NUM_CHANNELS		8
+#define BITS_PER_BYTE			8
 
-struct spd_by_pointer {
-	size_t spd_data_len;
-	uintptr_t spd_data_ptr;
+#define LPDDR4X_CHANNELS		8
+#define LPDDR4X_BYTES_PER_CHANNEL	2
+
+enum mem_topology {
+	MEMORY_DOWN,	/* Supports reading SPD from CBFS or in-memory pointer. */
 };
 
-enum mem_info_read_type {
-	NOT_EXISTING,	/* No memory in this channel */
-	READ_SPD_CBFS,	/* Find spd file in CBFS. */
-	READ_SPD_MEMPTR	/* Find spd data from pointer. */
+enum md_spd_loc {
+	 /* Read SPD from pointer provided to memory location. */
+	SPD_MEMPTR,
+	/* Read SPD using index into spd.bin in CBFS.  */
+	SPD_CBFS,
 };
 
 struct spd_info {
-	enum mem_info_read_type read_type;
-	union spd_data_by {
-		/* To identify spd file when read_type is READ_SPD_CBFS. */
-		int spd_index;
+	enum mem_topology topology;
+
+	/* SPD info for Memory down topology */
+	enum md_spd_loc md_spd_loc;
+	union {
+		/* Used for SPD_CBFS */
+		uint8_t cbfs_index;
 
-		/* To find spd data when read_type is READ_SPD_MEMPTR. */
-		struct spd_by_pointer spd_data_ptr_info;
-	} spd_spec;
+		struct {
+			/* Used for SPD_MEMPTR */
+			uintptr_t data_ptr;
+			size_t data_len;
+		};
+	};
 };
 
 /* Board-specific memory configuration information */
-struct mb_lpddr4x_cfg {
-	/* DQ mapping */
-	uint8_t dq_map[NUM_CHANNELS][BYTES_PER_CHANNEL * BITS_PER_BYTE];
+struct lpddr4x_cfg {
+	/*
+	 * DQ CPU<>DRAM map:
+	 * LPDDR4x memory interface has 2 DQs per channel. Each DQ consists of 8 bits(1
+	 * byte). Thus, dq_map is represented as DDR[7-0]_DQ[1-0][7:0], where
+	 * DDR[7-0] : LPDDR4x channel #
+	 * DQ[1-0]  : DQ # within the channel
+	 * [7:0]    : Bits within the DQ
+	 *
+	 * Index of the array represents DQ pin# on the CPU, whereas value in
+	 * the array represents DQ pin# on the memory part.
+	 */
+	uint8_t dq_map[LPDDR4X_CHANNELS][LPDDR4X_BYTES_PER_CHANNEL][BITS_PER_BYTE];
 
 	/*
-	 * DQS CPU<>DRAM map.  Each array entry represents a
-	 * mapping of a dq bit on the CPU to the bit it's connected to on
-	 * the memory part.  The array index represents the dqs bit number
-	 * on the memory part, and the values in the array represent which
-	 * pin on the CPU that DRAM pin connects to.
+	 * DQS CPU<>DRAM map:
+	 * LPDDR4x memory interface has 2 DQS pairs(P/N) per channel. Thus, dqs_map is
+	 * represented as DDR[7-0]_DQS[1:0], where
+	 * DDR[7-0]  : LPDDR4x channel #
+	 * DQS[1-0]  : DQS # within the channel
+	 *
+	 * Index of the array represents DQS pin# on the CPU, whereas value in
+	 * the array represents DQ pin# on the memory part.
 	 */
-	uint8_t dqs_map[NUM_CHANNELS][DQS_PER_CHANNEL];
+	uint8_t dqs_map[LPDDR4X_CHANNELS][LPDDR4X_BYTES_PER_CHANNEL];
 
 	/*
 	 * Early Command Training Enable/Disable Control
@@ -60,10 +79,7 @@ struct mb_lpddr4x_cfg {
 	uint8_t ect;
 };
 
-/* Initialize default memory configurations for dimm0-only lpddr4x */
-void meminit_lpddr4x_dimm0(FSP_M_CONFIG *mem_cfg,
-			   const struct mb_lpddr4x_cfg *board_cfg,
-			   const struct spd_info *spd,
-			   bool half_populated);
+void meminit_lpddr4x(FSP_M_CONFIG *mem_cfg, const struct lpddr4x_cfg *board_cfg,
+		const struct spd_info *spd, bool half_populated);
 
 #endif /* _SOC_TIGERLAKE_MEMINIT_H_ */
diff --git a/src/soc/intel/tigerlake/meminit.c b/src/soc/intel/tigerlake/meminit.c
index e6cdae0a30..864f0795e4 100644
--- a/src/soc/intel/tigerlake/meminit.c
+++ b/src/soc/intel/tigerlake/meminit.c
@@ -12,6 +12,10 @@
 #include <spd_bin.h>
 #include <string.h>
 
+/* If memory is half-populated, then upper half of the channels need to be left empty. */
+#define LPDDR4X_CHANNEL_UNPOPULATED(ch, half_populated)		\
+	((half_populated) && ((ch) >= (LPDDR4X_CHANNELS / 2)))
+
 enum dimm_enable_options {
 	ENABLE_BOTH_DIMMS = 0,
 	DISABLE_DIMM0 = 1,
@@ -19,145 +23,268 @@ enum dimm_enable_options {
 	DISABLE_BOTH_DIMMS = 3
 };
 
-#define MEM_INIT_CH_DQ_DQS_MAP(_mem_cfg, _b_cfg, _ch)		\
-	do {							\
-		memcpy(&_mem_cfg->DqMapCpu2DramCh ## _ch,	\
-		       &_b_cfg->dq_map[_ch],			\
-			sizeof(_b_cfg->dq_map[_ch]));		\
-		memcpy(&_mem_cfg->DqsMapCpu2DramCh ## _ch,	\
-			&_b_cfg->dqs_map[_ch],			\
-			sizeof(_b_cfg->dqs_map[_ch]));		\
-	} while (0)
+static uint8_t get_dimm_cfg(uintptr_t dimm0, uintptr_t dimm1)
+{
+	if (dimm0 && dimm1)
+		return ENABLE_BOTH_DIMMS;
+	if (!dimm0 && !dimm1)
+		return DISABLE_BOTH_DIMMS;
+	if (!dimm1)
+		return DISABLE_DIMM1;
+	if (!dimm0)
+		die("Disabling of only dimm0 is not supported!\n");
 
+	return DISABLE_BOTH_DIMMS;
+}
 
-static void spd_read_from_cbfs(const struct spd_info *spd,
-			       uintptr_t *spd_data_ptr, size_t *spd_data_len)
+static void init_spd_upds(FSP_M_CONFIG *mem_cfg, int channel, uintptr_t spd_dimm0,
+			  uintptr_t spd_dimm1)
 {
-	struct region_device spd_rdev;
-	size_t spd_index = spd->spd_spec.spd_index;
+	mem_cfg->Reserved9[channel] = get_dimm_cfg(spd_dimm0, spd_dimm1);
 
-	printk(BIOS_DEBUG, "SPD INDEX = %lu\n", spd_index);
-	if (get_spd_cbfs_rdev(&spd_rdev, spd_index) < 0)
-		die("spd.bin not found or incorrect index\n");
+	switch (channel) {
+	case 0:
+		mem_cfg->MemorySpdPtr00 = spd_dimm0;
+		mem_cfg->MemorySpdPtr01 = spd_dimm1;
+		break;
 
-	*spd_data_len = region_device_sz(&spd_rdev);
+	case 1:
+		mem_cfg->MemorySpdPtr02 = spd_dimm0;
+		mem_cfg->MemorySpdPtr03 = spd_dimm1;
+		break;
 
-	/* Memory leak is ok since we have memory mapped boot media */
-	assert(CONFIG(BOOT_DEVICE_MEMORY_MAPPED));
+	case 2:
+		mem_cfg->MemorySpdPtr04 = spd_dimm0;
+		mem_cfg->MemorySpdPtr05 = spd_dimm1;
+		break;
+
+	case 3:
+		mem_cfg->MemorySpdPtr06 = spd_dimm0;
+		mem_cfg->MemorySpdPtr07 = spd_dimm1;
+		break;
+
+	case 4:
+		mem_cfg->MemorySpdPtr08 = spd_dimm0;
+		mem_cfg->MemorySpdPtr09 = spd_dimm1;
+		break;
+
+	case 5:
+		mem_cfg->MemorySpdPtr10 = spd_dimm0;
+		mem_cfg->MemorySpdPtr11 = spd_dimm1;
+		break;
+
+	case 6:
+		mem_cfg->MemorySpdPtr12 = spd_dimm0;
+		mem_cfg->MemorySpdPtr13 = spd_dimm1;
+		break;
 
-	*spd_data_ptr = (uintptr_t)rdev_mmap_full(&spd_rdev);
+	case 7:
+		mem_cfg->MemorySpdPtr14 = spd_dimm0;
+		mem_cfg->MemorySpdPtr15 = spd_dimm1;
+		break;
+
+	default:
+		die("Invalid channel: %d\n", channel);
+	}
 }
 
-static void get_spd_data(const struct spd_info *spd,
-			 uintptr_t *spd_data_ptr, size_t *spd_data_len)
+static inline void init_spd_upds_empty(FSP_M_CONFIG *mem_cfg, int channel)
 {
-	if (spd->read_type == READ_SPD_MEMPTR) {
-		*spd_data_ptr = spd->spd_spec.spd_data_ptr_info.spd_data_ptr;
-		*spd_data_len = spd->spd_spec.spd_data_ptr_info.spd_data_len;
-		return;
-	}
+	init_spd_upds(mem_cfg, channel, 0, 0);
+}
 
-	if (spd->read_type == READ_SPD_CBFS) {
-		spd_read_from_cbfs(spd, spd_data_ptr, spd_data_len);
-		return;
+static inline void init_spd_upds_dimm0(FSP_M_CONFIG *mem_cfg, int channel, uintptr_t spd_dimm0)
+{
+	init_spd_upds(mem_cfg, channel, spd_dimm0, 0);
+}
+
+static void init_dq_upds(FSP_M_CONFIG *mem_cfg, int byte_pair, const uint8_t *dq_byte0,
+			 const uint8_t *dq_byte1)
+{
+	uint8_t *dq_upd;
+
+	switch (byte_pair) {
+	case 0:
+		dq_upd = mem_cfg->DqMapCpu2DramCh0;
+		break;
+	case 1:
+		dq_upd = mem_cfg->DqMapCpu2DramCh1;
+		break;
+	case 2:
+		dq_upd = mem_cfg->DqMapCpu2DramCh2;
+		break;
+	case 3:
+		dq_upd = mem_cfg->DqMapCpu2DramCh3;
+		break;
+	case 4:
+		dq_upd = mem_cfg->DqMapCpu2DramCh4;
+		break;
+	case 5:
+		dq_upd = mem_cfg->DqMapCpu2DramCh5;
+		break;
+	case 6:
+		dq_upd = mem_cfg->DqMapCpu2DramCh6;
+		break;
+	case 7:
+		dq_upd = mem_cfg->DqMapCpu2DramCh7;
+		break;
+	default:
+		die("Invalid byte_pair: %d\n", byte_pair);
 	}
 
-	die("no valid way to read SPD info");
+	if (dq_byte0 && dq_byte1) {
+		memcpy(dq_upd, dq_byte0, BITS_PER_BYTE);
+		memcpy(dq_upd + BITS_PER_BYTE, dq_byte1, BITS_PER_BYTE);
+	} else {
+		memset(dq_upd, 0, BITS_PER_BYTE * 2);
+	}
 }
 
-static void meminit_dq_dqs_map(FSP_M_CONFIG *mem_cfg,
-			       const struct mb_lpddr4x_cfg *board_cfg,
-			       bool half_populated)
+static inline void init_dq_upds_empty(FSP_M_CONFIG *mem_cfg, int byte_pair)
 {
-	MEM_INIT_CH_DQ_DQS_MAP(mem_cfg, board_cfg, 0);
-	MEM_INIT_CH_DQ_DQS_MAP(mem_cfg, board_cfg, 1);
-	MEM_INIT_CH_DQ_DQS_MAP(mem_cfg, board_cfg, 2);
-	MEM_INIT_CH_DQ_DQS_MAP(mem_cfg, board_cfg, 3);
-
-	if (half_populated)
-		return;
-
-	MEM_INIT_CH_DQ_DQS_MAP(mem_cfg, board_cfg, 4);
-	MEM_INIT_CH_DQ_DQS_MAP(mem_cfg, board_cfg, 5);
-	MEM_INIT_CH_DQ_DQS_MAP(mem_cfg, board_cfg, 6);
-	MEM_INIT_CH_DQ_DQS_MAP(mem_cfg, board_cfg, 7);
+	init_dq_upds(mem_cfg, byte_pair, NULL, NULL);
 }
 
-static void meminit_channels_dimm0(FSP_M_CONFIG *mem_cfg,
-				   const struct mb_lpddr4x_cfg *board_cfg,
-				   uintptr_t spd_data_ptr,
-				   bool half_populated)
+static void init_dqs_upds(FSP_M_CONFIG *mem_cfg, int byte_pair, uint8_t dqs_byte0,
+			  uint8_t dqs_byte1)
 {
-	uint8_t dimm_cfg = DISABLE_DIMM1; /* Use only DIMM0 */
-
-	/* Channel 0 */
-	mem_cfg->Reserved9[0] = dimm_cfg;
-	mem_cfg->MemorySpdPtr00 = spd_data_ptr;
-	mem_cfg->MemorySpdPtr01 = 0;
-
-	/* Channel 1 */
-	mem_cfg->Reserved9[1] = dimm_cfg;
-	mem_cfg->MemorySpdPtr02 = spd_data_ptr;
-	mem_cfg->MemorySpdPtr03 = 0;
-
-	/* Channel 2 */
-	mem_cfg->Reserved9[2] = dimm_cfg;
-	mem_cfg->MemorySpdPtr04 = spd_data_ptr;
-	mem_cfg->MemorySpdPtr05 = 0;
-
-	/* Channel 3 */
-	mem_cfg->Reserved9[3] = dimm_cfg;
-	mem_cfg->MemorySpdPtr06 = spd_data_ptr;
-	mem_cfg->MemorySpdPtr07 = 0;
-
-	if (half_populated) {
-		printk(BIOS_INFO, "%s: DRAM half-populated\n", __func__);
-		dimm_cfg = DISABLE_BOTH_DIMMS;
-		spd_data_ptr = 0;
+	uint8_t *dqs_upd;
+
+	switch (byte_pair) {
+	case 0:
+		dqs_upd = mem_cfg->DqsMapCpu2DramCh0;
+		break;
+	case 1:
+		dqs_upd = mem_cfg->DqsMapCpu2DramCh1;
+		break;
+	case 2:
+		dqs_upd = mem_cfg->DqsMapCpu2DramCh2;
+		break;
+	case 3:
+		dqs_upd = mem_cfg->DqsMapCpu2DramCh3;
+		break;
+	case 4:
+		dqs_upd = mem_cfg->DqsMapCpu2DramCh4;
+		break;
+	case 5:
+		dqs_upd = mem_cfg->DqsMapCpu2DramCh5;
+		break;
+	case 6:
+		dqs_upd = mem_cfg->DqsMapCpu2DramCh6;
+		break;
+	case 7:
+		dqs_upd = mem_cfg->DqsMapCpu2DramCh7;
+		break;
+	default:
+		die("Invalid byte_pair: %d\n", byte_pair);
 	}
 
-	/* Channel 4 */
-	mem_cfg->Reserved9[4] = dimm_cfg;
-	mem_cfg->MemorySpdPtr08 = spd_data_ptr;
-	mem_cfg->MemorySpdPtr09 = 0;
+	dqs_upd[0] = dqs_byte0;
+	dqs_upd[1] = dqs_byte1;
+}
 
-	/* Channel 5 */
-	mem_cfg->Reserved9[5] = dimm_cfg;
-	mem_cfg->MemorySpdPtr10 = spd_data_ptr;
-	mem_cfg->MemorySpdPtr11 = 0;
+static inline void init_dqs_upds_empty(FSP_M_CONFIG *mem_cfg, int byte_pair)
+{
+	init_dqs_upds(mem_cfg, byte_pair, 0, 0);
+}
 
-	/* Channel 6 */
-	mem_cfg->Reserved9[6] = dimm_cfg;
-	mem_cfg->MemorySpdPtr12 = spd_data_ptr;
-	mem_cfg->MemorySpdPtr13 = 0;
+static void read_spd_from_cbfs(uint8_t index, uintptr_t *data, size_t *len)
+{
+	struct region_device spd_rdev;
 
-	/* Channel 7 */
-	mem_cfg->Reserved9[7] = dimm_cfg;
-	mem_cfg->MemorySpdPtr14 = spd_data_ptr;
-	mem_cfg->MemorySpdPtr15 = 0;
+	printk(BIOS_DEBUG, "SPD INDEX = %u\n", index);
+	if (get_spd_cbfs_rdev(&spd_rdev, index) < 0)
+		die("spd.bin not found or incorrect index\n");
 
-	meminit_dq_dqs_map(mem_cfg, board_cfg, half_populated);
-}
+	/* Memory leak is ok since we have memory mapped boot media */
+	assert(CONFIG(BOOT_DEVICE_MEMORY_MAPPED));
 
-/* Initialize onboard memory configurations for lpddr4x */
-void meminit_lpddr4x_dimm0(FSP_M_CONFIG *mem_cfg,
-			   const struct mb_lpddr4x_cfg *board_cfg,
-			   const struct spd_info *spd,
-			   bool half_populated)
+	*len = region_device_sz(&spd_rdev);
+	*data = (uintptr_t)rdev_mmap_full(&spd_rdev);
+}
 
+static void read_md_spd(const struct spd_info *info, uintptr_t *data, size_t *len)
 {
-	size_t spd_data_len;
-	uintptr_t spd_data_ptr;
+	if (info->md_spd_loc == SPD_MEMPTR) {
+		*data = info->data_ptr;
+		*len = info->data_len;
+	} else if (info->md_spd_loc == SPD_CBFS) {
+		read_spd_from_cbfs(info->cbfs_index, data, len);
+	} else {
+		die("Not a valid location(%d) for Memory-down SPD!\n", info->md_spd_loc);
+	}
 
-	get_spd_data(spd, &spd_data_ptr, &spd_data_len);
-	print_spd_info((unsigned char *)spd_data_ptr);
+	print_spd_info((unsigned char *)data);
+}
+
+void meminit_lpddr4x(FSP_M_CONFIG *mem_cfg, const struct lpddr4x_cfg *board_cfg,
+			const struct spd_info *info, bool half_populated)
+
+{
+	size_t spd_len;
+	uintptr_t spd_data;
+	int i;
 
-	mem_cfg->MemorySpdDataLen = spd_data_len;
-	meminit_channels_dimm0(mem_cfg, board_cfg, spd_data_ptr,
-			       half_populated);
+	if (info->topology != MEMORY_DOWN)
+		die("LPDDR4x only support memory-down topology.\n");
 
-	/* LPDDR4 does not allow interleaved memory */
+	/* LPDDR4x does not allow interleaved memory */
 	mem_cfg->DqPinsInterleaved = 0;
 	mem_cfg->ECT = board_cfg->ect;
 	mem_cfg->MrcSafeConfig = 0x1;
+
+	read_md_spd(info, &spd_data, &spd_len);
+	mem_cfg->MemorySpdDataLen = spd_len;
+
+	for (i = 0; i < LPDDR4X_CHANNELS; i++) {
+		if (LPDDR4X_CHANNEL_UNPOPULATED(i, half_populated))
+			init_spd_upds_empty(mem_cfg, i);
+		else
+			init_spd_upds_dimm0(mem_cfg, i, spd_data);
+	}
+
+	/*
+	 * LPDDR4x memory interface has 2 DQs per channel. Each DQ consists of 8 bits (1
+	 * byte). However, FSP UPDs for DQ Map expect a DQ pair (i.e. mapping for 2 bytes) in
+	 * each UPD.
+	 *
+	 * Thus, init_dq_upds() needs to be called for dq pair of each channel.
+	 * DqMapCpu2DramCh0 --> dq_map[CHAN=0][0-1]
+	 * DqMapCpu2DramCh1 --> dq_map[CHAN=1][0-1]
+	 * DqMapCpu2DramCh2 --> dq_map[CHAN=2][0-1]
+	 * DqMapCpu2DramCh3 --> dq_map[CHAN=3][0-1]
+	 * DqMapCpu2DramCh4 --> dq_map[CHAN=4][0-1]
+	 * DqMapCpu2DramCh5 --> dq_map[CHAN=5][0-1]
+	 * DqMapCpu2DramCh6 --> dq_map[CHAN=6][0-1]
+	 * DqMapCpu2DramCh7 --> dq_map[CHAN=7][0-1]
+	 */
+	for (i = 0; i < LPDDR4X_CHANNELS; i++) {
+		if (LPDDR4X_CHANNEL_UNPOPULATED(i, half_populated))
+			init_dq_upds_empty(mem_cfg, i);
+		else
+			init_dq_upds(mem_cfg, i, board_cfg->dq_map[i][0],
+				     board_cfg->dq_map[i][1]);
+	}
+
+	/*
+	 * LPDDR4x memory interface has 2 DQS pairs per channel. FSP UPDs for DQS Map expect a
+	 * pair in each UPD.
+	 *
+	 * Thus, init_dqs_upds() needs to be called for dqs pair of each channel.
+	 * DqsMapCpu2DramCh0 --> dqs_map[CHAN=0][0-1]
+	 * DqsMapCpu2DramCh1 --> dqs_map[CHAN=1][0-1]
+	 * DqsMapCpu2DramCh2 --> dqs_map[CHAN=2][0-1]
+	 * DqsMapCpu2DramCh3 --> dqs_map[CHAN=3][0-1]
+	 * DqsMapCpu2DramCh4 --> dqs_map[CHAN=4][0-1]
+	 * DqsMapCpu2DramCh5 --> dqs_map[CHAN=5][0-1]
+	 * DqsMapCpu2DramCh6 --> dqs_map[CHAN=6][0-1]
+	 * DqsMapCpu2DramCh7 --> dqs_map[CHAN=7][0-1]
+	 */
+	for (i = 0; i < LPDDR4X_CHANNELS; i++) {
+		if (LPDDR4X_CHANNEL_UNPOPULATED(i, half_populated))
+			init_dqs_upds_empty(mem_cfg, i);
+		else
+			init_dqs_upds(mem_cfg, i, board_cfg->dqs_map[i][0],
+				      board_cfg->dqs_map[i][1]);
+	}
 }