Timothy Pearson (tpearson@raptorengineeringinc.com) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/12058
-gerrit
commit dd2b820877797c6aba0b231ec1789fcf1331ef99 Author: Timothy Pearson tpearson@raptorengineeringinc.com Date: Thu Aug 27 13:19:34 2015 -0500
nb/amd/mct_ddr3: Fix odd rank data corruption
The odd rank of each DIMM could experience data corruption due to incorrect DQS training. Fix the DQS training algorithm.
Change-Id: Ibc51f5052d5189e45b3d9aa98ca8febbfe13f178 Signed-off-by: Timothy Pearson tpearson@raptorengineeringinc.com --- src/northbridge/amd/amdmct/mct_ddr3/mctdqs_d.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-)
diff --git a/src/northbridge/amd/amdmct/mct_ddr3/mctdqs_d.c b/src/northbridge/amd/amdmct/mct_ddr3/mctdqs_d.c index 06597e2..9362a60 100644 --- a/src/northbridge/amd/amdmct/mct_ddr3/mctdqs_d.c +++ b/src/northbridge/amd/amdmct/mct_ddr3/mctdqs_d.c @@ -1320,9 +1320,9 @@ static uint8_t TrainDQSRdWrPos_D_Fam15(struct MCTStatStruc *pMCTstat, Receiver = receiver_start;
/* There are four receiver pairs, loosely associated with chipselects. - * This is essentially looping over each DIMM. + * This is essentially looping over each rank within each DIMM. */ - for (; Receiver < receiver_end; Receiver += 2) { + for (; Receiver < receiver_end; Receiver++) { dimm = (Receiver >> 1); if ((Receiver & 0x1) == 0) { /* Even rank of DIMM */ @@ -1336,18 +1336,27 @@ static uint8_t TrainDQSRdWrPos_D_Fam15(struct MCTStatStruc *pMCTstat, continue; }
+#if DQS_TRAIN_DEBUG > 0 + printk(BIOS_DEBUG, "TrainDQSRdWrPos: Training DQS read/write position for receiver %d (DIMM %d)\n", Receiver, dimm); +#endif + /* Initialize variables */ for (lane = lane_start; lane < lane_end; lane++) { passing_dqs_delay_found[lane] = 0; } - memset(dqs_results_array, 0, sizeof(dqs_results_array)); + if ((Receiver & 0x1) == 0) { + /* Even rank of DIMM */ + memset(dqs_results_array, 0, sizeof(dqs_results_array)); + + /* Read initial read / write DQS delays */ + read_dqs_write_timing_control_registers(initial_write_dqs_delay, dev, dct, dimm, index_reg); + read_dqs_read_data_timing_registers(initial_read_dqs_delay, dev, dct, dimm, index_reg);
- /* Read initial read / write DQS delays */ - read_dqs_write_timing_control_registers(initial_write_dqs_delay, dev, dct, dimm, index_reg); - read_dqs_read_data_timing_registers(initial_read_dqs_delay, dev, dct, dimm, index_reg); + /* Read current settings of other (previously trained) lanes */ + read_dqs_write_data_timing_registers(initial_write_data_timing, dev, dct, dimm, index_reg); + }
- /* Read current settings of other (previously trained) lanes */ - read_dqs_write_data_timing_registers(initial_write_data_timing, dev, dct, dimm, index_reg); + /* Initialize iterators */ memcpy(current_write_data_delay, initial_write_data_timing, sizeof(current_write_data_delay));
for (lane = lane_start; lane < lane_end; lane++) {