[coreboot-gerrit] Change in coreboot[master]: nb/intel/sandybridge/raminit: Fix ECC scrub

[Patrick Rudolph (Code Review)]

Hello build bot (Jenkins), Patrick Georgi, Jonathan Kollasch, Angel Pons, Arthur Heymans, Patrick Rudolph,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/40721

to look at the new patch set (#2).

Change subject: nb/intel/sandybridge/raminit: Fix ECC scrub
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nb/intel/sandybridge/raminit: Fix ECC scrub

The scrubbing method was never correct nor tested.
Fix that by observations made on mrc.bin.

* Add ECC test code when DEBUG_RAM_SETUP
* Move ECC scrubbing after set_scrambling_seed() to be able to observe
  what has been cleared.
* ECC scrubbing must happen after dram_dimm_set_mapping()
* Move method out of try_init_dram_ddr3()
* Add comments with observations made while fixing the code

Tested on HPZ220 with ECC memory and XeonE3 CPU:
The whole memory is now scrubbed.

Change-Id: Ia9fcc236fbf73f51fe944c6dda5d22ba9d334ec7
Signed-off-by: Patrick Rudolph 
---
M src/northbridge/intel/sandybridge/raminit.c
M src/northbridge/intel/sandybridge/raminit_common.c
M src/northbridge/intel/sandybridge/raminit_native.c
3 files changed, 80 insertions(+), 34 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/21/40721/2