From 7f5a97ce98120561dff449cbbf9f953bd9b6d623 Mon Sep 17 00:00:00 2001 From: Angel Pons Date: Fri, 13 Nov 2020 16:58:46 +0100 Subject: nb/intel/sandybridge: Rename `read_training` function Given that it sets the receive enable mode bit in the GDCRTRAININGMOD register, it's clear that this is about receive enable calibration. Remove a potentially-outdated comment. Proper documentation will be written once code refactoring and various improvements are complete. Change-Id: Iaefc8905adf2878bec3b43494dc53530064a9f5d Signed-off-by: Angel Pons Reviewed-on: https://review.coreboot.org/c/coreboot/+/47576 Reviewed-by: Arthur Heymans Tested-by: build bot (Jenkins) --- src/northbridge/intel/sandybridge/raminit_common.c | 20 +------------------- src/northbridge/intel/sandybridge/raminit_common.h | 2 +- src/northbridge/intel/sandybridge/raminit_native.c | 2 +- 3 files changed, 3 insertions(+), 21 deletions(-) (limited to 'src/northbridge/intel/sandybridge') diff --git a/src/northbridge/intel/sandybridge/raminit_common.c b/src/northbridge/intel/sandybridge/raminit_common.c index 5aaafdd9f1..5332e24f8b 100644 --- a/src/northbridge/intel/sandybridge/raminit_common.c +++ b/src/northbridge/intel/sandybridge/raminit_common.c @@ -1316,25 +1316,7 @@ static void compute_final_logic_delay(ramctr_timing *ctrl, int channel, int slot printram("4028 -= %d;\n", logic_delay_min); } -/* - * Compensate the skew between DQS and DQs. - * - * To ease PCB design, a small skew between Data Strobe signals and Data Signals is allowed. - * The controller has to measure and compensate this skew for every byte-lane. By delaying - * either all DQ signals or DQS signal, a full phase shift can be introduced. It is assumed - * that one byte-lane's DQs signals have the same routing delay. - * - * To measure the actual skew, the DRAM is placed in "read leveling" mode. In read leveling - * mode the DRAM-chip outputs an alternating periodic pattern. The memory controller iterates - * over all possible values to do a full phase shift and issues read commands. With DQS and - * DQ in phase the data being read is expected to alternate on every byte: - * - * 0xFF 0x00 0xFF ... - * - * Once the controller has detected this pattern a bit in the result register is set for the - * current phase shift. - */ -int read_training(ramctr_timing *ctrl) +int receive_enable_calibration(ramctr_timing *ctrl) { int channel, slotrank, lane; int err; diff --git a/src/northbridge/intel/sandybridge/raminit_common.h b/src/northbridge/intel/sandybridge/raminit_common.h index 4a7e8065c2..10dd59d844 100644 --- a/src/northbridge/intel/sandybridge/raminit_common.h +++ b/src/northbridge/intel/sandybridge/raminit_common.h @@ -400,7 +400,7 @@ void dram_dimm_set_mapping(ramctr_timing *ctrl, int training); void dram_zones(ramctr_timing *ctrl, int training); void dram_memorymap(ramctr_timing *ctrl, int me_uma_size); void dram_jedecreset(ramctr_timing *ctrl); -int read_training(ramctr_timing *ctrl); +int receive_enable_calibration(ramctr_timing *ctrl); int write_training(ramctr_timing *ctrl); int command_training(ramctr_timing *ctrl); int read_mpr_training(ramctr_timing *ctrl); diff --git a/src/northbridge/intel/sandybridge/raminit_native.c b/src/northbridge/intel/sandybridge/raminit_native.c index 454ba011ab..e0b5a3dfc2 100644 --- a/src/northbridge/intel/sandybridge/raminit_native.c +++ b/src/northbridge/intel/sandybridge/raminit_native.c @@ -680,7 +680,7 @@ int try_init_dram_ddr3(ramctr_timing *ctrl, int fast_boot, int s3resume, int me_ /* Prepare for memory training */ prepare_training(ctrl); - err = read_training(ctrl); + err = receive_enable_calibration(ctrl); if (err) return err; -- cgit v1.2.3