From: Stefan Roese <sr@denx.de>
Date: Fri, 18 Jul 2008 13:57:23 +0000 (+0200)
Subject: ppc4xx: Fix incorrect MODTx setup for some DIMM configurations
X-Git-Tag: v1.3.4-rc2~31^2~1
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=66fe183b1dd9c7534605147a8ecfed1c02345ee5;p=u-boot

ppc4xx: Fix incorrect MODTx setup for some DIMM configurations

This patch fixes a problem with incorrect MODTx (On Die Termination)
setup for a configuration with multiple DIMM's and multiple ranks.
Without this change Katmai was unable to boot Linux with DDR2 frequency
>= 533MHz and mem>=3GB. With this patch Katmai successfully boots Linux
with DDR2 frequency = 640MHz and mem=4GB.

Signed-off-by: Stefan Roese <sr@denx.de>
---

diff --git a/cpu/ppc4xx/44x_spd_ddr2.c b/cpu/ppc4xx/44x_spd_ddr2.c
index a27e276f25..e9940e8e5b 100644
--- a/cpu/ppc4xx/44x_spd_ddr2.c
+++ b/cpu/ppc4xx/44x_spd_ddr2.c
@@ -1150,50 +1150,50 @@ static void program_codt(unsigned long *dimm_populated,
 	if (dimm_type == SDRAM_DDR2) {
 		codt |= SDRAM_CODT_DQS_1_8_V_DDR2;
 		if ((total_dimm == 1) && (firstSlot == TRUE)) {
-			if (total_rank == 1) {
+			if (total_rank == 1) {	/* PUUU */
 				codt |= CALC_ODT_R(0);
 				modt0 = CALC_ODT_W(0);
 				modt1 = 0x00000000;
 				modt2 = 0x00000000;
 				modt3 = 0x00000000;
 			}
-			if (total_rank == 2) {
+			if (total_rank == 2) {	/* PPUU */
 				codt |= CALC_ODT_R(0) | CALC_ODT_R(1);
-				modt0 = CALC_ODT_W(0);
-				modt1 = CALC_ODT_W(0);
+				modt0 = CALC_ODT_W(0) | CALC_ODT_W(1);
+				modt1 = 0x00000000;
 				modt2 = 0x00000000;
 				modt3 = 0x00000000;
 			}
 		} else if ((total_dimm == 1) && (firstSlot != TRUE)) {
-			if (total_rank == 1) {
+			if (total_rank == 1) {	/* UUPU */
 				codt |= CALC_ODT_R(2);
 				modt0 = 0x00000000;
 				modt1 = 0x00000000;
 				modt2 = CALC_ODT_W(2);
 				modt3 = 0x00000000;
 			}
-			if (total_rank == 2) {
+			if (total_rank == 2) {	/* UUPP */
 				codt |= CALC_ODT_R(2) | CALC_ODT_R(3);
 				modt0 = 0x00000000;
 				modt1 = 0x00000000;
-				modt2 = CALC_ODT_W(2);
-				modt3 = CALC_ODT_W(2);
+				modt2 = CALC_ODT_W(2) | CALC_ODT_W(3);
+				modt3 = 0x00000000;
 			}
 		}
 		if (total_dimm == 2) {
-			if (total_rank == 2) {
+			if (total_rank == 2) {	/* PUPU */
 				codt |= CALC_ODT_R(0) | CALC_ODT_R(2);
 				modt0 = CALC_ODT_RW(2);
 				modt1 = 0x00000000;
 				modt2 = CALC_ODT_RW(0);
 				modt3 = 0x00000000;
 			}
-			if (total_rank == 4) {
+			if (total_rank == 4) {	/* PPPP */
 				codt |= CALC_ODT_R(0) | CALC_ODT_R(1) |
 					CALC_ODT_R(2) | CALC_ODT_R(3);
-				modt0 = CALC_ODT_RW(2);
+				modt0 = CALC_ODT_RW(2) | CALC_ODT_RW(3);
 				modt1 = 0x00000000;
-				modt2 = CALC_ODT_RW(0);
+				modt2 = CALC_ODT_RW(0) | CALC_ODT_RW(1);
 				modt3 = 0x00000000;
 			}
 		}