tree c846fc18062f1b07b0730586268c30708bba749d
parent 2c06ef9f8c4b96bc2970f812f0beddde374e3c3b
author Subrata Banik <subratabanik@google.com> 1688721682 +0000
committer Subrata Banik <subratabanik@google.com> 1689007348 +0000

mb/google/rex/var/ovis: Enable both Memory Channels (MC0 and MC1)

This patch skips reading the MEM_CH_SEL GPIO aka GPP_E13 to determine
the memory channel configuration. The signal behavior is not proper,
hence limiting the DIMM capacity to half (only MC0 is enabled).

This patch always reports the full memory capacity as in dual channel
(both MC0 and MC1 enabled).

This change is necessary to ensure that the system reports the correct
memory capacity, even if the MEM_CH_SEL GPIO is not working properly.

BUG=b:290174538
TEST=Able to detect 32GB memory capacity while booting google/ovis.

Without this patch:
  localhost ~ # cat /proc/meminfo
  MemTotal: 16183080 kB

With this patch:
  localhost ~ # cat /proc/meminfo
  MemTotal: 32673664 kB

Change-Id: I6c3fa941abb044b79b13785f7b65d09957f0487d
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/76359
Reviewed-by: Sumeet R Pawnikar <sumeet.r.pawnikar@intel.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>