diff options
Diffstat (limited to 'src/northbridge/intel')
| -rw-r--r-- | src/northbridge/intel/x4x/dq_dqs.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/src/northbridge/intel/x4x/dq_dqs.c b/src/northbridge/intel/x4x/dq_dqs.c index 64131d89b8..fbdb4f9f17 100644 --- a/src/northbridge/intel/x4x/dq_dqs.c +++ b/src/northbridge/intel/x4x/dq_dqs.c @@ -447,8 +447,12 @@ static int rt_find_dqs_limit(struct sysinfo *s, u8 channel, * - use the mean between the saved succeeding and failing value * - note0: bytelanes cannot be trained independently, so the delays need to be * adjusted and tested for all of them at the same time - * - note1: this memory controller appears to have per rank registers for these - * DQS rx delays, but only the one rank 0 seems to be used for all of them + * - note1: At this stage all ranks effectively use the rank0's rt_dqs settings, + * but later on their respective settings are used (TODO where is the + * 'switch' register??). So programming the results for all ranks at the end + * of the training. Programming on all ranks instead of all populated ranks, + * seems to be required, most likely because the signals can't really be generated + * separately. */ int do_read_training(struct sysinfo *s) { @@ -519,7 +523,9 @@ int do_read_training(struct sysinfo *s) printk(BIOS_ERR, "Huh? read training overflowed!!\n"); } - FOR_EACH_POPULATED_RANK_IN_CHANNEL(s->dimms, channel, rank) + /* Later on separate settings for each rank are used so program + all of them */ + FOR_EACH_RANK_IN_CHANNEL(rank) rt_set_dqs(channel, lane, rank, &s->rt_dqs[channel][lane]); printk(BIOS_DEBUG, "\tlane%d: %d.%d\n", |