From: Dongjiu Geng <gengdongjiu@xxxxxxxxxx> Add APEI/GHES detailed design document Signed-off-by: Dongjiu Geng <gengdongjiu@xxxxxxxxxx> Signed-off-by: Xiang Zheng <zhengxiang9@xxxxxxxxxx> --- docs/specs/acpi_hest_ghes.txt | 88 +++++++++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 docs/specs/acpi_hest_ghes.txt diff --git a/docs/specs/acpi_hest_ghes.txt b/docs/specs/acpi_hest_ghes.txt new file mode 100644 index 0000000000..690d4b2bd0 --- /dev/null +++ b/docs/specs/acpi_hest_ghes.txt @@ -0,0 +1,88 @@ +APEI tables generating and CPER record +============================= + +Copyright (C) 2019 Huawei Corporation. + +Design Details: +------------------- + + etc/acpi/tables etc/hardware_errors + ==================== ========================================== ++ +--------------------------+ +-----------------------+ +| | HEST | | address | +--------------+ +| +--------------------------+ | registers | | Error Status | +| | GHES1 | | +---------------------+ | Data Block 1 | +| +--------------------------+ +--------->| |error_block_address1 |----------->| +------------+ +| | ................. | | | +---------------------+ | | CPER | +| | error_status_address-----+-+ +------->| |error_block_address2 |--------+ | | CPER | +| | ................. | | | +---------------------+ | | | .... | +| | read_ack_register--------+-+ | | | .............. | | | | CPER | +| | read_ack_preserve | | | +-----------------------+ | | +------------+ +| | read_ack_write | | | +----->| |error_block_addressN |------+ | | Error Status | ++ +--------------------------+ | | | | +---------------------+ | | | Data Block 2 | +| | GHES2 | +-+-+----->| |read_ack_register1 | | +-->| +------------+ ++ +--------------------------+ | | | +---------------------+ | | | CPER | +| | ................. | | | +--->| |read_ack_register2 | | | | CPER | +| | error_status_address-----+---+ | | | +---------------------+ | | | .... | +| | ................. | | | | | ............. | | | | CPER | +| | read_ack_register--------+-----+-+ | +---------------------+ | +-+------------+ +| | read_ack_preserve | | +->| |read_ack_registerN | | | |.......... | +| | read_ack_write | | | | +---------------------+ | | +------------+ ++ +--------------------------| | | | | Error Status | +| | ............... | | | | | Data Block N | ++ +--------------------------+ | | +---->| +------------+ +| | GHESN | | | | | CPER | ++ +--------------------------+ | | | | CPER | +| | ................. | | | | | .... | +| | error_status_address-----+-----+ | | | CPER | +| | ................. | | +-+------------+ +| | read_ack_register--------+---------+ +| | read_ack_preserve | +| | read_ack_write | ++ +--------------------------+ + +(1) QEMU generates the ACPI HEST table. This table goes in the current + "etc/acpi/tables" fw_cfg blob. Each error source has different + notification types. + +(2) A new fw_cfg blob called "etc/hardware_errors" is introduced. QEMU + also need to populate this blob. The "etc/hardwre_errors" fw_cfg blob + contains an address registers table and an Error Status Data Block table. + +(3) The address registers table contains N Error Block Address entries + and N Read Ack Register entries, the size for each entry is 8-byte. + The Error Status Data Block table contains N Error Status Data Block + entries, the size for each entry is 4096(0x1000) bytes. The total size + for "etc/hardware_errors" fw_cfg blob is (N * 8 * 2 + N * 4096) bytes. + N is the kinds of hardware error sources. + +(4) QEMU generates the ACPI linker/loader script for the firmware, the + firmware pre-allocates memory for "etc/acpi/tables", "etc/hardware_errors" + and copies blobs content there. + +(5) QEMU generates N ADD_POINTER commands, which patch address in the + "error_status_address" fields of the HEST table with a pointer to the + corresponding "address registers" in "etc/hardware_errors" blob. + +(6) QEMU generates N ADD_POINTER commands, which patch address in the + "read_ack_register" fields of the HEST table with a pointer to the + corresponding "address registers" in "etc/hardware_errors" blob. + +(7) QEMU generates N ADD_POINTER commands for the firmware, which patch + address in the " error_block_address" fields with a pointer to the + respective "Error Status Data Block" in "etc/hardware_errors" blob. + +(8) QEMU defines a third and write-only fw_cfg blob which is called + "etc/hardware_errors_addr". Through that blob, the firmware can send back + the guest-side allocation addresses to QEMU. The "etc/hardware_errors_addr" + blob contains a 8-byte entry. QEMU generates a single WRITE_POINTER commands + for the firmware, the firmware will write back the start address of + "etc/hardware_errors" blob to fw_cfg file "etc/hardware_errors_addr". + +(9) When QEMU gets SIGBUS from the kernel, QEMU formats the CPER right into + guest memory, and then injects whatever interrupt (or assert whatever GPIO + line) as a notification which is necessary for notifying the guest. + +(10) This notification (in virtual hardware) will be handled by guest kernel, + guest APEI driver will read the CPER which is recorded by QEMU and do the + recovery. -- 2.19.1