On Tue, 14 May 2019 04:18:19 -0700
Dongjiu Geng <gengdongjiu@xxxxxxxxxx> wrote:
> Add APEI/GHES detailed design document
>
> Signed-off-by: Dongjiu Geng <gengdongjiu@xxxxxxxxxx>
> ---
> docs/specs/acpi_hest_ghes.txt | 97 +++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 97 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 0000000..fbfc787
> --- /dev/null
> +++ b/docs/specs/acpi_hest_ghes.txt
> @@ -0,0 +1,97 @@
> +APEI tables generating and CPER record
> +=============================
> +
> +Copyright (C) 2017 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 type.
> +
> +(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 one address registers table and one Error Status Data Block
s/one/a/
in both cases
> + table, all of which are pre-allocated.
drop /, all of which are pre-allocated./
> +
> +(3) The address registers table contains N Error Block Address entries
> + and N Read Ack Address 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.
where 'N' is specified?
> +
> +(4) QEMU generates the ACPI linker/loader script for the firmware
> +
> +(4a) The HEST table is part of "etc/acpi/tables", the firmware already
> + allocates the memory for it, because QEMU already generates an ALLOCATE
> + linker/loader command for it
> +
> +(4b) QEMU creates another ALLOCATE command for the "etc/hardware_errors"
> + blob. The firmware allocates memory for this blob and downloads it.
may be merge both points, like:
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 the downloaded "etc/hardware_errors"
> + blob.
s/the downloaded//
the same applies to to other similar occurrences below
> +
> +(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 the downloaded "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 the downloaded "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".
> Then
> + Qemu will know the Error Status Data Block for every error source. Each of
> + Error Status Data Block has fixed size which is 4096(0x1000).
this probably is not necessary.
> +
> +(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.
