mb/clevo/l140cu: clean up memcfg

The DQ and DQS byte maps do not apply to DDR4 configurations, thus
simply drop them.

Also drop ECT, as it's already initialized to zero and can't be used on
DDR4 anyway.

Further, trim down all the meaningless and/or wrong comments.

Change-Id: I32f1b7bb46eaaf0f0ecad1df310f5de988f64c85
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46249
Reviewed-by:  Felix Singer <felixsinger@posteo.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 5 insertions, 51 deletions

diff --git a/src/mainboard/clevo/cml-u/variants/l140cu/romstage.c b/src/mainboard/clevo/cml-u/variants/l140cu/romstage.c
index 44014831e0..4cad131765 100644
--- a/src/mainboard/clevo/cml-u/variants/l140cu/romstage.c
+++ b/src/mainboard/clevo/cml-u/variants/l140cu/romstage.c
@@ -13,66 +13,20 @@ static const struct cnl_mb_cfg memcfg = {
 		.spd_spec = {.spd_smbus_address = 0xa4},
 	},
 
-	/*
-	 * For each channel, there are 3 sets of DQ byte mappings,
-	 * where each set has a package 0 and a package 1 value (package 0
-	 * represents the first 64-bit lpddr4 chip combination, and package 1
-	 * represents the second 64-bit lpddr4 chip combination).
-	 * The first three sets are for CLK, CMD, and CTL.
-	 * The fsp package actually expects 6 sets, but the last 3 sets are
-	 * not used in CNL, so we only define the three sets that are used
-	 * and let the meminit_lpddr4() routine take care of clearing the
-	 * unused fields for the caller.
-	 */
-	.dq_map[DDR_CH0] = {
-		{0x0F, 0xF0}, {0x00, 0xF0}, {0x0F, 0xF0},
-		//{0x0F, 0x00}, {0xFF, 0x00}, {0xFF, 0x00}
-	},
-	.dq_map[DDR_CH1] = {
-		{0x33, 0xCC}, {0x00, 0xCC}, {0x33, 0xCC},
-		//{0x33, 0x00}, {0xFF, 0x00}, {0xFF, 0x00}
-	},
-
-	/*
-	 * DQS CPU<>DRAM map Ch0 and Ch1.  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_map[DDR_CH0] = {0, 1, 2, 3, 4, 5, 6, 7},
-	.dqs_map[DDR_CH1] = {1, 0, 2, 3, 4, 5, 6, 7},
-
-	/*
-	 * Rcomp resistor values.  These values represent the resistance in
-	 * ohms of the three rcomp resistors attached to the DDR_COMP_0,
-	 * DDR_COMP_1, and DDR_COMP_2 pins on the DRAM.
-	 */
+	/* Values of the resistors connected to the DDR_RCOMP_[2:0] pins of the CPU */
 	.rcomp_resistor = { 121, 81, 100 },
 
-	/*
-	 * Rcomp target values.  These will typically be the following
-	 * values for Cannon Lake : { 80, 40, 40, 40, 30 }
-	 */
+	/* Rcomp target values */
 	.rcomp_targets = { 100, 40, 20, 20, 26 },
 
-	/*
-	 * Indicates whether memory is interleaved.
-	 * Set to 1 for an interleaved design,
-	 * set to 0 for non-interleaved design.
-	 */
+	/* Interleaved ("back-to-back") pin mapping */
 	.dq_pins_interleaved = 1,
 
 	/*
-	 * VREF_CA configuration.
-	 * Set to 0 VREF_CA goes to both CH_A and CH_B,
-	 * set to 1 VREF_CA goes to CH_A and VREF_DQ_A goes to CH_B,
-	 * set to 2 VREF_CA goes to CH_A and VREF_DQ_B goes to CH_B.
+	 * DDR4 Vref mapping
+	 * VREF_CA goes to CH_A and VREF_DQ_B (DDR1_VREF_DQ) goes to CH_B.
 	 */
 	.vref_ca_config = 2,
-
-	/* Early Command Training */
-	.ect = 0,
 };
 
 void mainboard_memory_init_params(FSPM_UPD *memupd)