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From: Nate DeSimone <nathaniel.l.desimone@intel.com>
To: rafael@kernel.org
Cc: lenb@kernel.org, linux-acpi@vger.kernel.org, tony.luck@intel.com
Subject: [PATCH v3 0/2] ACPI: FPDT: expose FBPT and S3PT subtables via sysfs
Date: Tue, 24 Mar 2026 16:14:53 -0700	[thread overview]
Message-ID: <20260324231456.701-1-nathaniel.l.desimone@intel.com> (raw)

The ACPI Firmware Performance Data Table (FPDT) can contain two subtables:

1. Firmware Basic Boot Performance Table (FBPT)
2. S3 Performance Table (S3PT)

The existing /sys/firmware/acpi/tables/FPDT sysfs entry
only exposes the top-level FPDT header, not the subtables themselves.

This series adds sysfs attributes at /sys/firmware/acpi/fpdt/FBPT and
/sys/firmware/acpi/fpdt/S3PT that expose the raw contents of these
subtables. This mirrors the model used by /sys/firmware/dmi/tables/DMI
for DMI/SMBIOS data, and allows userspace tools to parse newer FPDT
record types defined in recent ACPI specifications[1] (e.g. String
Event Records, Microcontroller Boot Performance Data Records, etc.)
without requiring kernel changes for each new record type.

[1]
https://uefi.org/specs/ACPI/6.6/05_ACPI_Software_Programming_Model.html#performance-event-record-types

Signed-off-by: Nate DeSimone <nathaniel.l.desimone@intel.com>
---

Changes in v3:
- changed sysfs_create_bin_file() error handling to a non-fatal warning

Changes in v2:
- removed the intermediate /sys/firmware/acpi/tables/ subdirectory
- tightened file permissions for FBPT and S3PT from 0444 to 0400
- added documentation to Documentation/ABI/testing/sysfs-firmware-acpi

---
Nate DeSimone (2):
  ACPI: FPDT: expose FBPT and S3PT subtables via sysfs
  Documentation: ABI: add FBPT and S3PT entries to sysfs-firmware-acpi

 Documentation/ABI/testing/sysfs-firmware-acpi |  6 ++++
 drivers/acpi/acpi_fpdt.c                      | 28 +++++++++++++++++++
 2 files changed, 34 insertions(+)


base-commit: 24f9515de8778410e4b84c85b196c9850d2c1e18
-- 
2.34.1


             reply	other threads:[~2026-03-24 23:17 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-24 23:14 Nate DeSimone [this message]
2026-03-24 23:14 ` [PATCH v3 1/2] ACPI: FPDT: expose FBPT and S3PT subtables via sysfs Nate DeSimone
2026-03-26 15:32   ` Rafael J. Wysocki
2026-03-24 23:14 ` [PATCH v3 2/2] Documentation: ABI: add FBPT and S3PT entries to sysfs-firmware-acpi Nate DeSimone

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