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 a27e276f25ca75b5c53f300c00f87c9e80a5df91..e9940e8e5b50e8a7ed7f2bbc9c144fcfae64923c 100644 (file)
--- 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;
                        }
                }