nb/amd/amdmct/mct_ddr3: Save and restore SkewMemClk for S3 resume

Change-Id: Ib331bd330530d4d6be5eb7351d9f9b15c135dd63
Signed-off-by: Timothy Pearson <tpearson@raptorengineeringinc.com>
Reviewed-on: https://review.coreboot.org/13167
Tested-by: build bot (Jenkins)
Tested-by: Raptor Engineering Automated Test Stand <noreply@raptorengineeringinc.com>
Reviewed-by: Martin Roth <martinroth@google.com>

src/northbridge/amd/amdmct/mct_ddr3/mct_d.h

@@ -729,7 +729,7 @@ struct amd_s3_persistent_mct_channel_data {
 	uint32_t f3x5c;
 	uint32_t f3x60;
 
-	/* Family 15h-specific registers (90 dwords) */
+	/* Family 15h-specific registers (91 dwords) */
 	uint32_t f2x200;
 	uint32_t f2x204;
 	uint32_t f2x208;
@@ -785,8 +785,9 @@ struct amd_s3_persistent_mct_channel_data {
 	uint32_t f2x9cx0d0fc231;
 	uint32_t f2x9cx0d0f0_0_f_31[9];		/* [lane] */
 	uint32_t f2x9cx0d0f8021;
+	uint32_t f2x9cx0d0fe00a;
 
-	/* TOTAL: 342 dwords */
+	/* TOTAL: 343 dwords */
 } __attribute__((packed));
 
 struct amd_s3_persistent_node_data {

src/northbridge/amd/amdmct/mct_ddr3/s3utils.c

@@ -454,6 +454,9 @@ void copy_mct_data_to_save_variable(struct amd_s3_persistent_data* persistent_da
 					data->f2x9cx0d0f0_0_f_31[i] = read_amd_dct_index_register_dct(dev_fn2, node, channel, 0x98, 0x0d0f0031 | (i << 8));
 
 				data->f2x9cx0d0f8021 = read_amd_dct_index_register_dct(dev_fn2, node, channel, 0x98, 0x0d0f8021);
+
+				if (channel == 1)
+					data->f2x9cx0d0fe00a = read_amd_dct_index_register_dct(dev_fn2, node, channel, 0x98, 0x0d0fe00a);
 			}
 
 			/* Stage 4 */
@@ -796,6 +799,9 @@ void restore_mct_data_from_save_variable(struct amd_s3_persistent_data* persiste
 					write_amd_dct_index_register_dct(PCI_DEV(0, 0x18 + node, 2), node, channel, 0x98, 0x0d0f0031 | (i << 8), data->f2x9cx0d0f0_0_f_31[i]);
 
 				write_amd_dct_index_register_dct(PCI_DEV(0, 0x18 + node, 2), node, channel, 0x98, 0x0d0f8021, data->f2x9cx0d0f8021);
+
+				if (channel == 1)
+					write_amd_dct_index_register_dct(PCI_DEV(0, 0x18 + node, 2), node, channel, 0x98, 0x0d0fe00a, data->f2x9cx0d0fe00a);
 			}
 		}
 	}