nb/sandybridge: Add a kconfig option to ignore XMP max DIMMs
XMP profiles can have a restriction on max supported DIMMs per channel,
but many configurations work with more DIMMs.
This is relevant on mainboards with 2 DIMM slots per channel (usually 4
in total). Populating both slots with DIMMs that support XMP profiles only
with 1 DIMM per channel turns off said XMP profiles.
TEST=On a system with two DIMM slots per channel populate both slots on
one channel and ensure that DIMMs run with XMP profiles enabled.
Change-Id: I1f22d981afcef0ee73785823b0a943cf3d3564e3
Signed-off-by: Vagiz Trakhanov <rakkin@autistici.org>
Reviewed-on: https://review.coreboot.org/21841
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/src/northbridge/intel/sandybridge/Kconfig b/src/northbridge/intel/sandybridge/Kconfig
index 1a47f0d..043e8de 100644
--- a/src/northbridge/intel/sandybridge/Kconfig
+++ b/src/northbridge/intel/sandybridge/Kconfig
@@ -54,6 +54,15 @@
Disabled by default as it might causes system instability.
Handle with care!
+config NATIVE_RAMINIT_IGNORE_XMP_MAX_DIMMS
+ bool "Ignore XMP profile max DIMMs per channel"
+ default n
+ depends on USE_NATIVE_RAMINIT
+ help
+ Ignore the max DIMMs per channel restriciton defined in XMP profiles.
+ Disabled by default as it might cause system instability.
+ Handle with care!
+
config CBFS_SIZE
hex
default 0x100000
diff --git a/src/northbridge/intel/sandybridge/raminit.c b/src/northbridge/intel/sandybridge/raminit.c
index bdba748..12384b4 100644
--- a/src/northbridge/intel/sandybridge/raminit.c
+++ b/src/northbridge/intel/sandybridge/raminit.c
@@ -234,7 +234,10 @@
printram("XMP profile supports %u DIMMs, but %u DIMMs are installed.\n",
dimm->dimm[channel][slot].dimms_per_channel,
dimms_on_channel);
- spd_decode_ddr3(&dimm->dimm[channel][slot], spd[spd_slot]);
+ if (IS_ENABLED(CONFIG_NATIVE_RAMINIT_IGNORE_XMP_MAX_DIMMS))
+ printk(BIOS_WARNING, "XMP maximum DIMMs will be ignored.\n");
+ else
+ spd_decode_ddr3(&dimm->dimm[channel][slot], spd[spd_slot]);
} else if (dimm->dimm[channel][slot].voltage != 1500) {
/* TODO: support other DDR3 voltage than 1500mV */
printram("XMP profile's requested %u mV is unsupported.\n",