path: root/src/arch/x86/init
diff options
authorAaron Durbin <adurbin@chromium.org>2013-05-10 00:33:32 -0500
committerAaron Durbin <adurbin@google.com>2013-05-16 01:29:50 +0200
commit716738a6b84535f731ee9749f161505945eab93c (patch)
tree1698dbb1c22e5feca94bba6df30a49ed5f0d8d36 /src/arch/x86/init
parentadc300d88b35ceafafb4d4b6426c6458dc46b685 (diff)
x86: add cache-as-ram migration option
There are some boards that do a significant amount of work after cache-as-ram is torn down but before ramstage is loaded. For example, using vboot to verify the ramstage is one such operation. However, there are pieces of code that are executed that reference global variables that are linked in the cache-as-ram region. If those variables are referenced after cache-as-ram is torn down then the values observed will most likely be incorrect. Therefore provide a Kconfig option to select cache-as-ram migration to memory using cbmem. This option is named CAR_MIGRATION. When enabled, the address of cache-as-ram variables may be obtained dynamically. Additionally, when cache-as-ram migration occurs the cache-as-ram data region for global variables is copied into cbmem. There are also automatic callbacks for other modules to perform their own migration, if necessary. Change-Id: I2e77219647c2bd2b1aa845b262be3b2543f1fcb7 Signed-off-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: http://review.coreboot.org/3232 Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src/arch/x86/init')
1 files changed, 12 insertions, 0 deletions
diff --git a/src/arch/x86/init/romstage.ld b/src/arch/x86/init/romstage.ld
index 88c56573a..f44185f24 100644
--- a/src/arch/x86/init/romstage.ld
+++ b/src/arch/x86/init/romstage.ld
@@ -35,6 +35,10 @@ SECTIONS
. = ALIGN(16);
+ _car_migrate_start = .;
+ *(.car.migrate);
+ _car_migrate_end = .;
+ . = ALIGN(16);
_erom = .;
@@ -48,8 +52,16 @@ SECTIONS
.car.data . (NOLOAD) : {
+ _car_data_start = .;
+ /* The cbmem_console section comes last to take advantage of
+ * a zero-sized array to hold the memconsole contents that
+ * grows to a bound of CONFIG_CONSOLE_CAR_BUFFER_SIZE. However,
+ * collisions within the cache-as-ram region cannot be
+ * statically checked because the cache-as-ram region usage is
+ * cpu/chipset dependent. */
+ _car_data_end = .;
_bogus = ASSERT((SIZEOF(.car.data) <= CONFIG_DCACHE_RAM_SIZE), "Cache as RAM area is too full");