[PATCH v3 0/5] Introduce Platform Firmware Runtime Update and Telemetry drivers

From: Chen Yu
Date: Thu Sep 16 2021 - 11:48:24 EST


High Service Level Agreements (SLAs) requires that the system runs without
service interruptions. Generally, system firmware provides runtime services
such as RAS(Reliability, Availability and Serviceability) features, UEFI runtime
services and ACPI services. Currently if there is any firmware code changes in
these code area, the system firmware update and reboot is required. Example of
bug fix could be wrong register size or location of the register. This means
customer services are not available during the firmware upgrade, which could
approach several minutes, resulting in not able to meet SLAs.

Intel provides a mechanism named Management Mode Runtime Update to help the users
update the firmware without having to reboot[1].

This series provides the following facilities.

1. Perform a runtime firmware driver update and activate.
2. Ability to inject firmware code at runtime, for dynamic instrumentation.
3. Facility to retrieve logs from runtime firmware update and activate telemetry.
(The telemetry is based on runtime firmware update: it records the logs during
runtime update(code injection and driver update).

The Management Mode Runtime Update OS Interface Specification[1] provides two ACPI
device objects to interface with system firmware to perform these updates. This patch
series introduces the drivers for those ACPI devices.

[1] https://uefi.org/sites/default/files/resources/Intel_MM_OS_Interface_Spec_Rev100.pdf

=============
- Change from v2 to v3:
- Use valid types for structures that cross the user/kernel boundry
in the uapi header. (Greg Kroah-Hartman)
- Rename the structure in uapi to start with a prefix pfru so as
to avoid confusing in the global namespace. (Greg Kroah-Hartman)
- Change from v1 to v2:
- Add a spot in index.rst so it becomes part of the docs build
(Jonathan Corbet).
- Sticking to the 80-column limit(Jonathan Corbet).
- Underline lengths should match the title text(Jonathan Corbet).
- Use literal blocks for the code samples(Jonathan Corbet).
- Add sanity check for duplicated instance of ACPI device.
- Update the driver to work with allocated pfru_device objects.
(Mike Rapoport)
- For each switch case pair, get rid of the magic case numbers
and add a default clause with the error handling.(Mike Rapoport)
- Move the obj->type checks outside the switch to reduce redundancy.
(Mike Rapoport)
- Parse the code_inj_id and drv_update_id at driver initialization time
to reduce the re-parsing at runtime. (Mike Rapoport)
- Explain in detail how the size needs to be adjusted when doing
version check. (Mike Rapoport)
- Rename parse_update_result() to dump_update_result()
(Mike Rapoport)
- Remove redundant return.(Mike Rapoport)
- Do not expose struct capsulate_buf_info to uapi, since it is
not needed in userspace. (Mike Rapoport)
- Do not allow non-root user to run this test.(Shuah Khan)
- Test runs on platform without pfru_telemetry should skip
instead of reporting failure/error.(Shuah Khan)
- Reuse uapi/linux/pfru.h instead of copying it into the test
directory. (Mike Rapoport)

Chen Yu (5):
Documentation: Introduce Platform Firmware Runtime Update
documentation
efi: Introduce EFI_FIRMWARE_MANAGEMENT_CAPSULE_HEADER and
corresponding structures
drivers/acpi: Introduce Platform Firmware Runtime Update device driver
drivers/acpi: Introduce Platform Firmware Runtime Update Telemetry
selftests/pfru: add test for Platform Firmware Runtime Update and
Telemetry

.../userspace-api/ioctl/ioctl-number.rst | 1 +
Documentation/x86/index.rst | 1 +
Documentation/x86/pfru.rst | 100 +++
drivers/acpi/Kconfig | 1 +
drivers/acpi/Makefile | 1 +
drivers/acpi/pfru/Kconfig | 29 +
drivers/acpi/pfru/Makefile | 3 +
drivers/acpi/pfru/pfru_telemetry.c | 412 +++++++++++++
drivers/acpi/pfru/pfru_update.c | 567 ++++++++++++++++++
include/linux/efi.h | 50 ++
include/uapi/linux/pfru.h | 149 +++++
tools/testing/selftests/Makefile | 1 +
tools/testing/selftests/pfru/Makefile | 7 +
tools/testing/selftests/pfru/config | 2 +
tools/testing/selftests/pfru/pfru_test.c | 328 ++++++++++
15 files changed, 1652 insertions(+)
create mode 100644 Documentation/x86/pfru.rst
create mode 100644 drivers/acpi/pfru/Kconfig
create mode 100644 drivers/acpi/pfru/Makefile
create mode 100644 drivers/acpi/pfru/pfru_telemetry.c
create mode 100644 drivers/acpi/pfru/pfru_update.c
create mode 100644 include/uapi/linux/pfru.h
create mode 100644 tools/testing/selftests/pfru/Makefile
create mode 100644 tools/testing/selftests/pfru/config
create mode 100644 tools/testing/selftests/pfru/pfru_test.c

--
2.25.1