Commit graph

2 commits

Author SHA1 Message Date
Lee Leahy
5f4b4c4296 arch/x86: Add bootblock and postcar support for SOC MTRR access
Quark does not support the rdmsr and wrmsr instructions.  Use SOC
specific routines to configure the MTRRs on Quark based platforms.
Add cpu_common.c as a build dependency to provide access to the routine
cpu_phys_address_size.

TEST=Build and run on Galileo Gen2

Change-Id: I43b7067c66c5c55b42097937e862078adf17fb19
Signed-off-by: Lee Leahy <leroy.p.leahy@intel.com>
Reviewed-on: https://review.coreboot.org/15846
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2016-07-27 13:50:39 +02:00
Aaron Durbin
7f8afe0631 arch/x86: introduce postcar stage/phase
Certain chipsets don't have a memory-mapped boot media
so their code execution for stages prior to DRAM initialization
is backed by SRAM or cache-as-ram. The postcar stage/phase
handles the cache-as-ram situation where in order to tear down
cache-as-ram one needs to be executing out of a backing
store that isn't transient. By current definition, cache-as-ram
is volatile and tearing it down leads to its contents disappearing.
Therefore provide a shim layer, postcar, that's loaded into
memory and executed which does 2 things:

1. Tears down cache-as-ram with a chipset helper function.
2. Loads and runs ramstage.

Because those 2 things are executed out of ram there's no issue
of the code's backing store while executing the code that
tears down cache-as-ram. The current implementation makes no
assumption regarding cacheability of the DRAM itself. If the
chipset code wishes to cache DRAM for loading of the postcar
stage/phase then it's also up to the chipset to handle any
coherency issues pertaining to cache-as-ram destruction.

Change-Id: Ia58efdadd0b48f20cfe7de2f49ab462306c3a19b
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/14140
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-by: Furquan Shaikh <furquan@google.com>
2016-03-23 14:24:30 +01:00