baytrail: adjust cache policy during romstage

The caching policy for romstage was previously using a 32KiB
of cache-as-ram for both the MRC wrapper and the romstage stack/data.
It also used a 32KiB code cache region. The BWG's limitations for
the code and data region before memory is up was wrong. It consists
of a 16-way set associative 1MiB cache. As long as enough addresses
are not read there isn't a risk of evicting the data/stack.

Now create a 64KiB cache-as-ram region split evenly between romstage
and the MRC wrapper. Additionally cache the memory just below
4GiB in CBFS size. This will cover any code and read-only data needed.

BUG=chrome-os-partner:22858
BRANCH=None
TEST=Built and booted quickly with corresponding changes to MRC warpper.
CQ-DEPEND=CL:*146175

Change-Id: I021cecb886a9c0622005edc389136d22905d4520
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/172150
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/4868
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
This commit is contained in:
Aaron Durbin 2013-10-07 16:24:44 -05:00 committed by Aaron Durbin
parent 3f5a1ffb83
commit 08a4613219
2 changed files with 10 additions and 19 deletions

View File

@ -92,15 +92,6 @@ endif # CACHE_MRC_SETTINGS
endif # HAVE_MRC
config CAR_TILE_SIZE
hex
default 0x8000
help
The tile size is the limit that can be assigned to cache-as-ram
region as well as the amount of code cache used during cache-as-ram.
Also note that (DCACHE_RAM_BASE ^ MRC_BIN_ADDRESS) & CAR_TILE_SIZE ==
CAR_TILE_SIZE.
# Cache As RAM region layout:
#
# +-------------+ DCACHE_RAM_BASE + DCACHE_RAM_SIZE + DCACHE_RAM_MRC_VAR_SIZE
@ -123,11 +114,11 @@ config CAR_TILE_SIZE
config DCACHE_RAM_BASE
hex
default 0xff7f8000
default 0xff800000
config DCACHE_RAM_SIZE
hex
default 0x1000
default 0x8000
help
The size of the cache-as-ram region required during bootblock
and/or romstage. Note DCACHE_RAM_SIZE and DCACHE_RAM_MRC_VAR_SIZE
@ -135,7 +126,7 @@ config DCACHE_RAM_SIZE
config DCACHE_RAM_MRC_VAR_SIZE
hex
default 0x7000
default 0x8000
help
The amount of cache-as-ram region required by the reference code.

View File

@ -31,10 +31,10 @@
(CONFIG_DCACHE_RAM_SIZE + CONFIG_DCACHE_RAM_MRC_VAR_SIZE)
#define CACHE_AS_RAM_BASE CONFIG_DCACHE_RAM_BASE
/* Enough room to cache CAR_TILE_SIZE starting at MRC_BIN_ADDRESS */
#define CACHE_MRC_BASE (CONFIG_MRC_BIN_ADDRESS)
#define CACHE_MRC_MASK (~(CONFIG_CAR_TILE_SIZE - 1))
/* Cache all of CBFS just below 4GiB as Write-Protect type. */
#define CODE_CACHE_SIZE (CONFIG_CBFS_SIZE)
#define CODE_CACHE_BASE (-CODE_CACHE_SIZE)
#define CODE_CACHE_MASK (~(CODE_CACHE_SIZE - 1))
#define CPU_PHYSMASK_HI ((1 << (CONFIG_CPU_ADDR_BITS - 32)) - 1)
#define NoEvictMod_MSR 0x2e0
@ -109,14 +109,14 @@ wait_for_sipi:
wrmsr
post_code(0x25)
/* Set Cache-as-RAM base address. */
/* Set code caching up for romstage. */
movl $(MTRRphysBase_MSR(1)), %ecx
movl $(CACHE_MRC_BASE | MTRR_TYPE_WRPROT), %eax
movl $(CODE_CACHE_BASE | MTRR_TYPE_WRPROT), %eax
xorl %edx, %edx
wrmsr
movl $(MTRRphysMask_MSR(1)), %ecx
movl $(CACHE_MRC_MASK | MTRRphysMaskValid), %eax
movl $(CODE_CACHE_MASK | MTRRphysMaskValid), %eax
movl $CPU_PHYSMASK_HI, %edx
wrmsr