[coreboot-gerrit] Patch set updated for coreboot: 71982c0 coreboot: differentiate on early reliable writable globals

[Aaron Durbin (adurbin@google.com)]

Aaron Durbin (adurbin at google.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/8943

-gerrit

commit 71982c002214b5effe62ce2722430297cab4057e
Author: Aaron Durbin <adurbin at chromium.org>
Date:   Tue Mar 24 09:20:45 2015 -0500

    coreboot: differentiate on early reliable writable globals
    
    There is a big difference between the boards supported in coreboot
    and the properties they provide within each stage during the bootflow.
    The leads to core infrastructure relying on supporting the least
    common denominator when writing APIs.
    
    Therefore, provide PLATFORM_HAS_EARLY_WRITABLE_GLOBALS which indicates
    that the platform has reliable writable global variables in the early
    stages of boot. For x86 that would be romstage, and for the other
    architetures which have SRAM it would encompass bootblock and romstage.
    
    Change-Id: I2cefeaee0551ee241e138fcee0d199679002c3be
    Signed-off-by: Aaron Durbin <adurbin at chromium.org>
---
 src/Kconfig | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/Kconfig b/src/Kconfig
index 7aee478..2625266 100644
--- a/src/Kconfig
+++ b/src/Kconfig
@@ -293,6 +293,25 @@ config SYSTEM_TYPE_LAPTOP
        default n
        bool
 
+config PLATFORM_HAS_EARLY_WRITABLE_GLOBALS
+	bool
+	default y if !ARCH_X86
+	help
+	 This option signals to the rest of the infrastructure that
+	 the platform supports writable globals in bootblock and
+	 romstage. Fox traditional x86 systems without any SRAM this
+	 would mean cache-as-ram globals are migrated correctly from
+	 the CAR area once memory is trained. After the migration the
+	 variables are accessible using the CAR API. This behavior
+	 puts such x86 systems on par with ARM and MIPS systems.
+
+config PLATFORM_NO_EARLY_WRITABLE_GLOBALS
+	bool
+	default y if !PLATFORM_HAS_EARLY_WRITABLE_GLOBALS
+	help
+	 This is just the opposite of PLATFORM_HAS_EARLY_WRITABLE_GLOBALS
+	 to enable cleaner Makefiles.
+
 menu "Chipset"
 
 comment "CPU"