diff options
| author | Gang Chen <gang.c.chen@intel.com> | 2024-05-22 19:58:23 +0800 |
|---|---|---|
| committer | Felix Held <felix-coreboot@felixheld.de> | 2024-09-30 16:25:34 +0000 |
| commit | b161d90f065e9da96e8e464335c939ab45dca821 (patch) | |
| tree | 688b45e672d78aaee0bcfee9cfc827dbe8bb58a5 /src/arch/x86 | |
| parent | 540d605f484913b885af9fd2b3084db685770960 (diff) | |
arch/x86: Configure EBDA through Kconfig
EBDA (Extended BIOS Data Area) is a memory area below 0xA0000 and
one of the default areas where OS will scan ACPI RSDP pointer from.
coreboot's default EBDA's starting address is 0xF6000, which is in
PAM (Programmable Attribute Map) F-segment's scope. For some platforms
without writeable PAM-F segment (e.g. some simics virtual platforms),
corboot's default EBDA is not writable.
Make DEFAULT_EBDA_LOWMEM, DEFAULT_EBDA_SEGMENT, DEFAULT_EBDA_SIZE
as Kconfig items so that coreboot's EBDA could be relocated to a
writable low memory place.
Change-Id: Icd7ba0c902560f7d498934392685dc2af9c5ce09
Signed-off-by: Gang Chen <gang.c.chen@intel.com>
Co-authored-by: Shuo Liu <shuo.liu@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/84321
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-by: Jérémy Compostella <jeremy.compostella@intel.com>
Diffstat (limited to 'src/arch/x86')
| -rw-r--r-- | src/arch/x86/Kconfig | 17 | ||||
| -rw-r--r-- | src/arch/x86/ebda.c | 13 |
2 files changed, 21 insertions, 9 deletions
diff --git a/src/arch/x86/Kconfig b/src/arch/x86/Kconfig index 16d8a7041d..4737e3cca1 100644 --- a/src/arch/x86/Kconfig +++ b/src/arch/x86/Kconfig @@ -422,4 +422,21 @@ config X86_BOOTBLOCK_EXTRA_PROGRAM_SZ The default value is 1024 bytes (1 KiB) for ChromeOS and 0 for other platforms. +config DEFAULT_EBDA_LOWMEM + hex + default 0x100000 + help + The default value of EBDA low memory is (1024 << 10). + +config DEFAULT_EBDA_SEGMENT + hex + default 0xF600 + help + The default value of EBDA segment is 0xF600. + +config DEFAULT_EBDA_SIZE + hex + default 0x400 + help + The default value of EBDA size is 0x400. endif diff --git a/src/arch/x86/ebda.c b/src/arch/x86/ebda.c index e835fcefef..f3e8fd2844 100644 --- a/src/arch/x86/ebda.c +++ b/src/arch/x86/ebda.c @@ -10,14 +10,9 @@ #define X86_EBDA_SEGMENT ((void *)0x40e) #define X86_EBDA_LOWMEM ((void *)0x413) -#define DEFAULT_EBDA_LOWMEM (1024 << 10) -#define DEFAULT_EBDA_SEGMENT 0xF600 -#define DEFAULT_EBDA_SIZE 0x400 - - static void *get_ebda_start(void) { - return (void *)((uintptr_t)DEFAULT_EBDA_SEGMENT << 4); + return (void *)((uintptr_t)CONFIG_DEFAULT_EBDA_SEGMENT << 4); } /* @@ -55,9 +50,9 @@ static void setup_default_ebda(void *unused) if (acpi_is_wakeup_s3()) return; - setup_ebda(DEFAULT_EBDA_LOWMEM, - DEFAULT_EBDA_SEGMENT, - DEFAULT_EBDA_SIZE); + setup_ebda(CONFIG_DEFAULT_EBDA_LOWMEM, + CONFIG_DEFAULT_EBDA_SEGMENT, + CONFIG_DEFAULT_EBDA_SIZE); } /* Ensure EBDA is prepared before Option ROMs. */ |