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| author | Patrick Rudolph <patrick.rudolph@9elements.com> | 2020-04-17 16:16:49 +0200 |
|---|---|---|
| committer | Michał Żygowski <michal.zygowski@3mdeb.com> | 2020-10-22 12:29:47 +0000 |
| commit | bc744f5893fc4d53275ed26dd8d968011c6a09c1 (patch) | |
| tree | fb283c9d57431020405a5404db04b425428f7709 /src/commonlib | |
| parent | a693fa06cd32da8239f820d833bb7a1bf55bf351 (diff) | |
| download | coreboot-bc744f5893fc4d53275ed26dd8d968011c6a09c1.tar.xz | |
drivers/smmstore: Implement SMMSTORE version 2
SMMSTORE version 2 is a complete redesign of the current driver. It is
not backwards-compatible with version 1, and only one version can be
used at a time.
Key features:
* Uses a fixed communication buffer instead of writing to arbitrary
memory addresses provided by untrusted ring0 code.
* Gives the caller full control over the used data format.
* Splits the store into smaller chunks to allow fault tolerant updates.
* Doesn't provide feedback about the actual read/written bytes, just
returns error or success in registers.
* Returns an error if the requested operation would overflow the
communication buffer.
Separate the SMMSTORE into 64 KiB blocks that can individually be
read/written/erased. To be used by payloads that implement a
FaultTolerant Variable store like TianoCore.
The implementation has been tested against EDK2 master.
An example EDK2 implementation can be found here:
https://github.com/9elements/edk2-1/commit/eb1127744a3a5d5c8ac4e8eb76f07e79c736dbe2
Change-Id: I25e49d184135710f3e6dd1ad3bed95de950fe057
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Signed-off-by: Christian Walter <christian.walter@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40520
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michał Żygowski <michal.zygowski@3mdeb.com>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
Diffstat (limited to 'src/commonlib')
| -rw-r--r-- | src/commonlib/include/commonlib/cbmem_id.h | 1 | ||||
| -rw-r--r-- | src/commonlib/include/commonlib/coreboot_tables.h | 17 |
2 files changed, 18 insertions, 0 deletions
diff --git a/src/commonlib/include/commonlib/cbmem_id.h b/src/commonlib/include/commonlib/cbmem_id.h index ac271a06bc..6b4d60469e 100644 --- a/src/commonlib/include/commonlib/cbmem_id.h +++ b/src/commonlib/include/commonlib/cbmem_id.h @@ -68,6 +68,7 @@ #define CBMEM_ID_ROM3 0x524f4d33 #define CBMEM_ID_FMAP 0x464d4150 #define CBMEM_ID_FSP_LOGO 0x4c4f474f +#define CBMEM_ID_SMM_COMBUFFER 0x53534d32 #define CBMEM_ID_TO_NAME_TABLE \ { CBMEM_ID_ACPI, "ACPI " }, \ diff --git a/src/commonlib/include/commonlib/coreboot_tables.h b/src/commonlib/include/commonlib/coreboot_tables.h index 6393c01e6e..44060025b3 100644 --- a/src/commonlib/include/commonlib/coreboot_tables.h +++ b/src/commonlib/include/commonlib/coreboot_tables.h @@ -80,6 +80,7 @@ enum { LB_TAG_TCPA_LOG = 0x0036, LB_TAG_FMAP = 0x0037, LB_TAG_PLATFORM_BLOB_VERSION = 0x0038, + LB_TAG_SMMSTOREV2 = 0x0039, LB_TAG_CMOS_OPTION_TABLE = 0x00c8, LB_TAG_OPTION = 0x00c9, LB_TAG_OPTION_ENUM = 0x00ca, @@ -484,4 +485,20 @@ struct cmos_checksum { #define CHECKSUM_PCBIOS 1 }; +/* SMMSTOREv2 record + * This record contains information to use SMMSTOREv2. + */ + +struct lb_smmstorev2 { + uint32_t tag; + uint32_t size; + uint32_t num_blocks; /* Number of writeable blocks in SMM */ + uint32_t block_size; /* Size of a block in byte. Default: 64 KiB */ + uint32_t mmap_addr; /* MMIO address of the store for read only access */ + uint32_t com_buffer; /* Physical address of the communication buffer */ + uint32_t com_buffer_size; /* Size of the communication buffer in bytes */ + uint8_t apm_cmd; /* The command byte to write to the APM I/O port */ + uint8_t unused[3]; /* Set to zero */ +}; + #endif |