coreboot.git - my copy of coreboot

Age	Commit message (Collapse)	Author
2018-05-24	nb/intel/x4x: Implement write leveling	Arthur Heymans
	DDR3 adapted a fly-by topology which allows for better signal integrity but at the same time requires additional calibration. This is done by settings the targeted rank in write leveling mode while disabling output buffer on the other ranks. After that the DQS signal gets sampled over DQ until a transition from high to low is found. Change-Id: I695969868b4534f87dd1f37244fdfac891a417f0 Signed-off-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-on: https://review.coreboot.org/22995 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
2018-05-01	nb/intel/x4x: Implement both read and write training	Arthur Heymans
	This training find the optimal write DQ delay and read DQS delay settings. It does so on all lanes at the same time, like vendor (training each lane individually has poor results). The results are stored in the sysinfo struct and restored on next boots and S3 resume. This potentially increases stability as optimal settings are chosen and is more necessary for DDR3 raminit where the write DQS delays are leveled/variable due to the flyby topology. TESTED on Intel DG43GT with (2G + 1G) on each channel, see that the results are quite close to the safe original ones (that previous worked fine) and tested with memtest86+. Change-Id: Iacdc63b91b4705d1a80437314bfe55385ea5b6c1 Signed-off-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-on: https://review.coreboot.org/22329 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Felix Held <felix-coreboot@felixheld.de>