* [PATCH v10 2/4] firmware: Move firmware attributes class helper
2026-07-28 8:20 [PATCH v10 0/4] coreboot CFR firmware attributes Sean Rhodes
2026-07-28 8:20 ` [PATCH v10 1/4] platform/x86: Sort firmware attributes class includes Sean Rhodes
@ 2026-07-28 8:20 ` Sean Rhodes
2026-07-28 8:32 ` sashiko-bot
2026-07-28 8:20 ` [PATCH v10 3/4] firmware: Rename google firmware directory to coreboot Sean Rhodes
2026-07-28 8:20 ` [PATCH v10 4/4] firmware: coreboot: Add CFR firmware attributes driver Sean Rhodes
3 siblings, 1 reply; 7+ messages in thread
From: Sean Rhodes @ 2026-07-28 8:20 UTC (permalink / raw)
To: chrome-platform
Cc: Corentin Chary, Luke D. Jones, Denis Benato, Hans de Goede,
Ilpo Järvinen, Prasanth Ksr, Jorge Lopez, Mark Pearson,
Derek J. Clark, Joshua Grisham, platform-driver-x86, linux-kernel,
Dell.Client.Kernel, Sean Rhodes, Huacai Chen, Michael S. Tsirkin,
Chen-Yu Tsai, Tzung-Bi Shih, Brian Norris, Julius Werner,
Thomas Zimmermann, Javier Martinez Canillas, Maarten Lankhorst,
Maxime Ripard, David Airlie, Simona Vetter, Krzysztof Kozlowski,
Bjorn Andersson, Geert Uytterhoeven, Dmitry Baryshkov,
Arnd Bergmann, Eric Biggers, Luca Weiss, Michal Simek, Sven Peter,
Florian Fainelli, Bjorn Helgaas, Takashi Sakamoto,
Danilo Krummrich, Uwe Kleine-König (The Capable Hub),
Titouan Ameline de Cadeville, Kees Cook, dri-devel, Oliver Lin
Move the firmware attributes class helper from drivers/platform/x86 to
drivers/firmware and expose its class declaration through a public Linux
header.
The helper is not x86-specific. Keeping it in firmware lets coreboot
firmware drivers use the standard firmware-attributes ABI without living
under platform/x86.
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Derek J. Clark <derekjohn.clark@gmail.com>
Tested-by: Oliver Lin <oliver@liuxiaozhen.dev>
Signed-off-by: Sean Rhodes <sean@starlabs.systems>
---
MAINTAINERS | 8 ++++++++
drivers/firmware/Kconfig | 3 +++
drivers/firmware/Makefile | 1 +
.../x86 => firmware}/firmware_attributes_class.c | 2 +-
drivers/platform/x86/Kconfig | 3 ---
drivers/platform/x86/Makefile | 2 --
drivers/platform/x86/asus-armoury.c | 2 +-
drivers/platform/x86/dell/dell-wmi-sysman/sysman.c | 2 +-
drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 2 +-
drivers/platform/x86/lenovo/think-lmi.c | 2 +-
drivers/platform/x86/lenovo/wmi-other.c | 2 +-
drivers/platform/x86/samsung-galaxybook.c | 2 +-
.../linux/firmware_attributes.h | 6 +++---
13 files changed, 22 insertions(+), 15 deletions(-)
rename drivers/{platform/x86 => firmware}/firmware_attributes_class.c (94%)
rename drivers/platform/x86/firmware_attributes_class.h => include/linux/firmware_attributes.h (60%)
diff --git a/MAINTAINERS b/MAINTAINERS
index 1ab8736850ea..3b21dc411b43 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10115,6 +10115,14 @@ F: include/linux/firewire.h
F: include/uapi/linux/firewire*.h
F: tools/firewire/
+FIRMWARE ATTRIBUTES CLASS
+M: Hans de Goede <hansg@kernel.org>
+M: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
+L: platform-driver-x86@vger.kernel.org
+S: Maintained
+F: drivers/firmware/firmware_attributes_class.c
+F: include/linux/firmware_attributes.h
+
FIRMWARE FRAMEWORK FOR ARMV8-A
M: Sudeep Holla <sudeep.holla@kernel.org>
L: linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index 12dc70254842..78a239f8bbef 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -8,6 +8,9 @@ menu "Firmware Drivers"
source "drivers/firmware/arm_scmi/Kconfig"
+config FW_ATTR_CLASS
+ tristate
+
config ARM_SCPI_PROTOCOL
tristate "ARM System Control and Power Interface (SCPI) Message Protocol"
depends on ARM || ARM64 || COMPILE_TEST
diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
index 4ddec2820c96..385b6e8b7fc6 100644
--- a/drivers/firmware/Makefile
+++ b/drivers/firmware/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_FIRMWARE_MEMMAP) += memmap.o
obj-$(CONFIG_MTK_ADSP_IPC) += mtk-adsp-ipc.o
obj-$(CONFIG_RASPBERRYPI_FIRMWARE) += raspberrypi.o
obj-$(CONFIG_FW_CFG_SYSFS) += qemu_fw_cfg.o
+obj-$(CONFIG_FW_ATTR_CLASS) += firmware_attributes_class.o
obj-$(CONFIG_SYSFB) += sysfb.o
obj-$(CONFIG_SYSFB_SIMPLEFB) += sysfb_simplefb.o
obj-$(CONFIG_TH1520_AON_PROTOCOL) += thead,th1520-aon.o
diff --git a/drivers/platform/x86/firmware_attributes_class.c b/drivers/firmware/firmware_attributes_class.c
similarity index 94%
rename from drivers/platform/x86/firmware_attributes_class.c
rename to drivers/firmware/firmware_attributes_class.c
index 736e96c186d9..503ecc288086 100644
--- a/drivers/platform/x86/firmware_attributes_class.c
+++ b/drivers/firmware/firmware_attributes_class.c
@@ -3,7 +3,7 @@
/* Firmware attributes class helper module */
#include <linux/module.h>
-#include "firmware_attributes_class.h"
+#include <linux/firmware_attributes.h>
const struct class firmware_attributes_class = {
.name = "firmware-attributes",
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index b54b5212b204..beed14c38b54 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -926,9 +926,6 @@ config DASHARO_ACPI
source "drivers/platform/x86/x86-android-tablets/Kconfig"
-config FW_ATTR_CLASS
- tristate
-
config INTEL_IMR
bool "Intel Isolated Memory Region support"
depends on X86_INTEL_QUARK && IOSF_MBI
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 872ac3842391..cab20a4145e3 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -63,8 +63,6 @@ obj-$(CONFIG_X86_PLATFORM_DRIVERS_HP) += hp/
# Hewlett Packard Enterprise
obj-$(CONFIG_UV_SYSFS) += uv_sysfs.o
-obj-$(CONFIG_FW_ATTR_CLASS) += firmware_attributes_class.o
-
# IBM Thinkpad (before 2005)
obj-$(CONFIG_IBM_RTL) += ibm_rtl.o
obj-$(CONFIG_SENSORS_HDAPS) += hdaps.o
diff --git a/drivers/platform/x86/asus-armoury.c b/drivers/platform/x86/asus-armoury.c
index f3d8c5a85762..e6af93608ec5 100644
--- a/drivers/platform/x86/asus-armoury.c
+++ b/drivers/platform/x86/asus-armoury.c
@@ -20,7 +20,7 @@
#include <linux/dmi.h>
#include <linux/err.h>
#include <linux/errno.h>
-#include "firmware_attributes_class.h"
+#include <linux/firmware_attributes.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/kmod.h>
diff --git a/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c b/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c
index 4ff9003c6589..963b3473991d 100644
--- a/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c
+++ b/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c
@@ -9,7 +9,7 @@
#include <linux/align.h>
#include <linux/dmi.h>
-#include "../../firmware_attributes_class.h"
+#include <linux/firmware_attributes.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/module.h>
diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
index 1965a329be48..f13f21580acd 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
@@ -8,7 +8,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/errno.h>
-#include "../../firmware_attributes_class.h"
+#include <linux/firmware_attributes.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/module.h>
diff --git a/drivers/platform/x86/lenovo/think-lmi.c b/drivers/platform/x86/lenovo/think-lmi.c
index 9e4b3e973de9..4437785aa1f2 100644
--- a/drivers/platform/x86/lenovo/think-lmi.c
+++ b/drivers/platform/x86/lenovo/think-lmi.c
@@ -15,7 +15,7 @@
#include <linux/array_size.h>
#include <linux/dmi.h>
#include <linux/errno.h>
-#include "../firmware_attributes_class.h"
+#include <linux/firmware_attributes.h>
#include <linux/fs.h>
#include <linux/mutex.h>
#include <linux/string_helpers.h>
diff --git a/drivers/platform/x86/lenovo/wmi-other.c b/drivers/platform/x86/lenovo/wmi-other.c
index fdebaa0a9992..b175971bb308 100644
--- a/drivers/platform/x86/lenovo/wmi-other.c
+++ b/drivers/platform/x86/lenovo/wmi-other.c
@@ -33,7 +33,7 @@
#include <linux/container_of.h>
#include <linux/device.h>
#include <linux/export.h>
-#include "../firmware_attributes_class.h"
+#include <linux/firmware_attributes.h>
#include <linux/gfp_types.h>
#include <linux/hwmon.h>
#include <linux/idr.h>
diff --git a/drivers/platform/x86/samsung-galaxybook.c b/drivers/platform/x86/samsung-galaxybook.c
index 74103c00b0c8..3911f60c23ea 100644
--- a/drivers/platform/x86/samsung-galaxybook.c
+++ b/drivers/platform/x86/samsung-galaxybook.c
@@ -14,7 +14,7 @@
#include <linux/acpi.h>
#include <linux/bits.h>
#include <linux/err.h>
-#include "firmware_attributes_class.h"
+#include <linux/firmware_attributes.h>
#include <linux/i8042.h>
#include <linux/init.h>
#include <linux/input.h>
diff --git a/drivers/platform/x86/firmware_attributes_class.h b/include/linux/firmware_attributes.h
similarity index 60%
rename from drivers/platform/x86/firmware_attributes_class.h
rename to include/linux/firmware_attributes.h
index d27abe54fcf9..d4026ba1fcc2 100644
--- a/drivers/platform/x86/firmware_attributes_class.h
+++ b/include/linux/firmware_attributes.h
@@ -2,11 +2,11 @@
/* Firmware attributes class helper module */
-#ifndef FW_ATTR_CLASS_H
-#define FW_ATTR_CLASS_H
+#ifndef _LINUX_FIRMWARE_ATTRIBUTES_H
+#define _LINUX_FIRMWARE_ATTRIBUTES_H
#include <linux/device/class.h>
extern const struct class firmware_attributes_class;
-#endif /* FW_ATTR_CLASS_H */
+#endif /* _LINUX_FIRMWARE_ATTRIBUTES_H */
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH v10 3/4] firmware: Rename google firmware directory to coreboot
2026-07-28 8:20 [PATCH v10 0/4] coreboot CFR firmware attributes Sean Rhodes
2026-07-28 8:20 ` [PATCH v10 1/4] platform/x86: Sort firmware attributes class includes Sean Rhodes
2026-07-28 8:20 ` [PATCH v10 2/4] firmware: Move firmware attributes class helper Sean Rhodes
@ 2026-07-28 8:20 ` Sean Rhodes
2026-07-28 8:20 ` [PATCH v10 4/4] firmware: coreboot: Add CFR firmware attributes driver Sean Rhodes
3 siblings, 0 replies; 7+ messages in thread
From: Sean Rhodes @ 2026-07-28 8:20 UTC (permalink / raw)
To: chrome-platform
Cc: Corentin Chary, Luke D. Jones, Denis Benato, Hans de Goede,
Ilpo Järvinen, Prasanth Ksr, Jorge Lopez, Mark Pearson,
Derek J. Clark, Joshua Grisham, platform-driver-x86, linux-kernel,
Dell.Client.Kernel, Sean Rhodes, Huacai Chen, Michael S. Tsirkin,
Chen-Yu Tsai, Tzung-Bi Shih, Brian Norris, Julius Werner,
Thomas Zimmermann, Javier Martinez Canillas, Maarten Lankhorst,
Maxime Ripard, David Airlie, Simona Vetter, Krzysztof Kozlowski,
Bjorn Andersson, Geert Uytterhoeven, Dmitry Baryshkov,
Arnd Bergmann, Eric Biggers, Luca Weiss, Michal Simek, Sven Peter,
Florian Fainelli, Bjorn Helgaas, Takashi Sakamoto,
Danilo Krummrich, Uwe Kleine-König (The Capable Hub),
Titouan Ameline de Cadeville, Kees Cook, dri-devel, Oliver Lin
Most drivers in drivers/firmware/google are coreboot table drivers rather
than Google-specific firmware drivers. Rename the directory to coreboot
and update the Kconfig prompt, build path and maintainer entry.
Rename the generic coreboot Kconfig symbols at the same time. Keep the old
CONFIG_GOOGLE_* names as transitional symbols so existing configurations
migrate to the new names.
Suggested-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Sean Rhodes <sean@starlabs.systems>
---
MAINTAINERS | 4 +-
arch/arm64/configs/defconfig | 6 +-
drivers/firmware/Kconfig | 2 +-
drivers/firmware/Makefile | 2 +-
drivers/firmware/{google => coreboot}/Kconfig | 74 ++++++++++++++-----
.../firmware/{google => coreboot}/Makefile | 10 +--
drivers/firmware/{google => coreboot}/cbmem.c | 0
.../{google => coreboot}/coreboot_table.c | 0
.../{google => coreboot}/coreboot_table.h | 0
.../framebuffer-coreboot.c | 0
drivers/firmware/{google => coreboot}/gsmi.c | 0
.../memconsole-coreboot.c | 0
.../memconsole-x86-legacy.c | 0
.../{google => coreboot}/memconsole.c | 0
.../{google => coreboot}/memconsole.h | 6 +-
drivers/firmware/{google => coreboot}/vpd.c | 0
.../{google => coreboot}/vpd_decode.c | 0
.../{google => coreboot}/vpd_decode.h | 0
drivers/gpu/drm/sysfb/Kconfig | 2 +-
19 files changed, 72 insertions(+), 34 deletions(-)
rename drivers/firmware/{google => coreboot}/Kconfig (64%)
rename drivers/firmware/{google => coreboot}/Makefile (51%)
rename drivers/firmware/{google => coreboot}/cbmem.c (100%)
rename drivers/firmware/{google => coreboot}/coreboot_table.c (100%)
rename drivers/firmware/{google => coreboot}/coreboot_table.h (100%)
rename drivers/firmware/{google => coreboot}/framebuffer-coreboot.c (100%)
rename drivers/firmware/{google => coreboot}/gsmi.c (100%)
rename drivers/firmware/{google => coreboot}/memconsole-coreboot.c (100%)
rename drivers/firmware/{google => coreboot}/memconsole-x86-legacy.c (100%)
rename drivers/firmware/{google => coreboot}/memconsole.c (100%)
rename drivers/firmware/{google => coreboot}/memconsole.h (82%)
rename drivers/firmware/{google => coreboot}/vpd.c (100%)
rename drivers/firmware/{google => coreboot}/vpd_decode.c (100%)
rename drivers/firmware/{google => coreboot}/vpd_decode.h (100%)
diff --git a/MAINTAINERS b/MAINTAINERS
index 3b21dc411b43..8c2634a8dc13 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11069,14 +11069,14 @@ S: Maintained
F: Documentation/networking/device_drivers/ethernet/google/gve.rst
F: drivers/net/ethernet/google
-GOOGLE FIRMWARE DRIVERS
+COREBOOT FIRMWARE DRIVERS
M: Tzung-Bi Shih <tzungbi@kernel.org>
R: Brian Norris <briannorris@chromium.org>
R: Julius Werner <jwerner@chromium.org>
L: chrome-platform@lists.linux.dev
S: Maintained
T: git git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux.git
-F: drivers/firmware/google/
+F: drivers/firmware/coreboot/
F: include/linux/coreboot.h
GOOGLE TENSOR SoC SUPPORT
diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 654a102cb5bc..32ec89a872d9 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -267,9 +267,9 @@ CONFIG_RASPBERRYPI_FIRMWARE=y
CONFIG_INTEL_STRATIX10_SERVICE=y
CONFIG_INTEL_STRATIX10_RSU=m
CONFIG_MTK_ADSP_IPC=m
-CONFIG_GOOGLE_FIRMWARE=y
-CONFIG_GOOGLE_CBMEM=m
-CONFIG_GOOGLE_COREBOOT_TABLE=m
+CONFIG_COREBOOT_FIRMWARE=y
+CONFIG_COREBOOT_CBMEM=m
+CONFIG_COREBOOT_TABLE=m
CONFIG_EFI_CAPSULE_LOADER=y
CONFIG_IMX_SCU=y
CONFIG_QCOM_TZMEM_MODE_SHMBRIDGE=y
diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index 78a239f8bbef..4df0a0ad18b8 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -293,7 +293,7 @@ endif # TURRIS_MOX_RWTM
source "drivers/firmware/arm_ffa/Kconfig"
source "drivers/firmware/broadcom/Kconfig"
source "drivers/firmware/cirrus/Kconfig"
-source "drivers/firmware/google/Kconfig"
+source "drivers/firmware/coreboot/Kconfig"
source "drivers/firmware/efi/Kconfig"
source "drivers/firmware/imx/Kconfig"
source "drivers/firmware/meson/Kconfig"
diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
index 385b6e8b7fc6..f8da96382680 100644
--- a/drivers/firmware/Makefile
+++ b/drivers/firmware/Makefile
@@ -30,7 +30,7 @@ obj-y += broadcom/
obj-y += cirrus/
obj-y += meson/
obj-y += microchip/
-obj-$(CONFIG_GOOGLE_FIRMWARE) += google/
+obj-$(CONFIG_COREBOOT_FIRMWARE) += coreboot/
obj-y += efi/
obj-y += imx/
obj-y += psci/
diff --git a/drivers/firmware/google/Kconfig b/drivers/firmware/coreboot/Kconfig
similarity index 64%
rename from drivers/firmware/google/Kconfig
rename to drivers/firmware/coreboot/Kconfig
index b78c644fa253..d273bd836245 100644
--- a/drivers/firmware/google/Kconfig
+++ b/drivers/firmware/coreboot/Kconfig
@@ -1,13 +1,16 @@
# SPDX-License-Identifier: GPL-2.0-only
-menuconfig GOOGLE_FIRMWARE
- bool "Google Firmware Drivers"
+menuconfig COREBOOT_FIRMWARE
+ bool "coreboot firmware drivers"
+ default GOOGLE_FIRMWARE
default n
help
- These firmware drivers are used by Google servers,
- Chromebooks and other devices using coreboot firmware.
+ These firmware drivers are used by devices running coreboot
+ firmware, including Chromebooks and some Google servers.
+ They include shared support for coreboot table entries and
+ drivers for CBMEM, framebuffer, firmware console and VPD records.
If in doubt, say "N".
-if GOOGLE_FIRMWARE
+if COREBOOT_FIRMWARE
config GOOGLE_SMI
tristate "SMI interface for Google platforms"
@@ -19,9 +22,10 @@ config GOOGLE_SMI
driver provides an interface for reading and writing NVRAM
variables.
-config GOOGLE_CBMEM
+config COREBOOT_CBMEM
tristate "CBMEM entries in sysfs"
- depends on GOOGLE_COREBOOT_TABLE
+ depends on COREBOOT_TABLE
+ default GOOGLE_CBMEM
help
CBMEM is a downwards-growing memory region created by the
Coreboot BIOS containing tagged data structures from the
@@ -34,9 +38,10 @@ config GOOGLE_CBMEM
memory for each entry in sysfs under
/sys/bus/coreboot/devices/cbmem-<id>.
-config GOOGLE_COREBOOT_TABLE
+config COREBOOT_TABLE
tristate "Coreboot Table Access"
depends on HAS_IOMEM && (ACPI || OF)
+ default GOOGLE_COREBOOT_TABLE
help
This option enables the coreboot_table module, which provides other
firmware modules access to the coreboot table. The coreboot table
@@ -44,42 +49,75 @@ config GOOGLE_COREBOOT_TABLE
device tree node /firmware/coreboot.
If unsure say N.
-config GOOGLE_MEMCONSOLE
+config COREBOOT_MEMCONSOLE_COMMON
tristate
- depends on GOOGLE_MEMCONSOLE_X86_LEGACY || GOOGLE_MEMCONSOLE_COREBOOT
+ depends on GOOGLE_MEMCONSOLE_X86_LEGACY || COREBOOT_MEMCONSOLE
+ default GOOGLE_MEMCONSOLE
config GOOGLE_MEMCONSOLE_X86_LEGACY
tristate "Firmware Memory Console - X86 Legacy support"
depends on X86 && ACPI && DMI
- select GOOGLE_MEMCONSOLE
+ select COREBOOT_MEMCONSOLE_COMMON
help
This option enables the kernel to search for a firmware log in
the EBDA on Google servers. If found, this log is exported to
userland in the file /sys/firmware/log.
+ This driver is limited to x86 systems that expose the legacy
+ Google EBDA console format.
-config GOOGLE_FRAMEBUFFER_COREBOOT
+config COREBOOT_FRAMEBUFFER
tristate "Coreboot Framebuffer"
- depends on GOOGLE_COREBOOT_TABLE
+ depends on COREBOOT_TABLE
+ default GOOGLE_FRAMEBUFFER_COREBOOT
help
This option enables the kernel to search for a framebuffer in
the coreboot table. If found, it is registered with a platform
device of type coreboot-framebuffer. Using the old device of
type simple-framebuffer is deprecated.
-config GOOGLE_MEMCONSOLE_COREBOOT
+config COREBOOT_MEMCONSOLE
tristate "Firmware Memory Console"
- depends on GOOGLE_COREBOOT_TABLE
- select GOOGLE_MEMCONSOLE
+ depends on COREBOOT_TABLE
+ select COREBOOT_MEMCONSOLE_COMMON
+ default GOOGLE_MEMCONSOLE_COREBOOT
help
This option enables the kernel to search for a firmware log in
the coreboot table. If found, this log is exported to userland
in the file /sys/firmware/log.
+ This is the coreboot-table backed variant of the firmware memory
+ console driver.
config GOOGLE_VPD
tristate "Vital Product Data"
- depends on GOOGLE_COREBOOT_TABLE
+ depends on COREBOOT_TABLE
help
This option enables the kernel to expose the content of Google VPD
under /sys/firmware/vpd.
+ VPD records carry firmware-provided key/value data used by
+ Google devices.
+
+endif # COREBOOT_FIRMWARE
-endif # GOOGLE_FIRMWARE
+config GOOGLE_FIRMWARE
+ bool
+ transitional
+
+config GOOGLE_CBMEM
+ tristate
+ transitional
+
+config GOOGLE_COREBOOT_TABLE
+ tristate
+ transitional
+
+config GOOGLE_MEMCONSOLE
+ tristate
+ transitional
+
+config GOOGLE_FRAMEBUFFER_COREBOOT
+ tristate
+ transitional
+
+config GOOGLE_MEMCONSOLE_COREBOOT
+ tristate
+ transitional
diff --git a/drivers/firmware/google/Makefile b/drivers/firmware/coreboot/Makefile
similarity index 51%
rename from drivers/firmware/google/Makefile
rename to drivers/firmware/coreboot/Makefile
index 8151e323cc43..e681f274417a 100644
--- a/drivers/firmware/google/Makefile
+++ b/drivers/firmware/coreboot/Makefile
@@ -1,14 +1,14 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_GOOGLE_SMI) += gsmi.o
-obj-$(CONFIG_GOOGLE_COREBOOT_TABLE) += coreboot_table.o
-obj-$(CONFIG_GOOGLE_FRAMEBUFFER_COREBOOT) += framebuffer-coreboot.o
-obj-$(CONFIG_GOOGLE_MEMCONSOLE) += memconsole.o
-obj-$(CONFIG_GOOGLE_MEMCONSOLE_COREBOOT) += memconsole-coreboot.o
+obj-$(CONFIG_COREBOOT_TABLE) += coreboot_table.o
+obj-$(CONFIG_COREBOOT_FRAMEBUFFER) += framebuffer-coreboot.o
+obj-$(CONFIG_COREBOOT_MEMCONSOLE_COMMON) += memconsole.o
+obj-$(CONFIG_COREBOOT_MEMCONSOLE) += memconsole-coreboot.o
obj-$(CONFIG_GOOGLE_MEMCONSOLE_X86_LEGACY) += memconsole-x86-legacy.o
# Must come after coreboot_table.o, as this driver depends on that bus type.
-obj-$(CONFIG_GOOGLE_CBMEM) += cbmem.o
+obj-$(CONFIG_COREBOOT_CBMEM) += cbmem.o
vpd-sysfs-y := vpd.o vpd_decode.o
obj-$(CONFIG_GOOGLE_VPD) += vpd-sysfs.o
diff --git a/drivers/firmware/google/cbmem.c b/drivers/firmware/coreboot/cbmem.c
similarity index 100%
rename from drivers/firmware/google/cbmem.c
rename to drivers/firmware/coreboot/cbmem.c
diff --git a/drivers/firmware/google/coreboot_table.c b/drivers/firmware/coreboot/coreboot_table.c
similarity index 100%
rename from drivers/firmware/google/coreboot_table.c
rename to drivers/firmware/coreboot/coreboot_table.c
diff --git a/drivers/firmware/google/coreboot_table.h b/drivers/firmware/coreboot/coreboot_table.h
similarity index 100%
rename from drivers/firmware/google/coreboot_table.h
rename to drivers/firmware/coreboot/coreboot_table.h
diff --git a/drivers/firmware/google/framebuffer-coreboot.c b/drivers/firmware/coreboot/framebuffer-coreboot.c
similarity index 100%
rename from drivers/firmware/google/framebuffer-coreboot.c
rename to drivers/firmware/coreboot/framebuffer-coreboot.c
diff --git a/drivers/firmware/google/gsmi.c b/drivers/firmware/coreboot/gsmi.c
similarity index 100%
rename from drivers/firmware/google/gsmi.c
rename to drivers/firmware/coreboot/gsmi.c
diff --git a/drivers/firmware/google/memconsole-coreboot.c b/drivers/firmware/coreboot/memconsole-coreboot.c
similarity index 100%
rename from drivers/firmware/google/memconsole-coreboot.c
rename to drivers/firmware/coreboot/memconsole-coreboot.c
diff --git a/drivers/firmware/google/memconsole-x86-legacy.c b/drivers/firmware/coreboot/memconsole-x86-legacy.c
similarity index 100%
rename from drivers/firmware/google/memconsole-x86-legacy.c
rename to drivers/firmware/coreboot/memconsole-x86-legacy.c
diff --git a/drivers/firmware/google/memconsole.c b/drivers/firmware/coreboot/memconsole.c
similarity index 100%
rename from drivers/firmware/google/memconsole.c
rename to drivers/firmware/coreboot/memconsole.c
diff --git a/drivers/firmware/google/memconsole.h b/drivers/firmware/coreboot/memconsole.h
similarity index 82%
rename from drivers/firmware/google/memconsole.h
rename to drivers/firmware/coreboot/memconsole.h
index aaff2b72b606..58899c2abaaa 100644
--- a/drivers/firmware/google/memconsole.h
+++ b/drivers/firmware/coreboot/memconsole.h
@@ -7,8 +7,8 @@
* Copyright 2017 Google Inc.
*/
-#ifndef __FIRMWARE_GOOGLE_MEMCONSOLE_H
-#define __FIRMWARE_GOOGLE_MEMCONSOLE_H
+#ifndef __FIRMWARE_COREBOOT_MEMCONSOLE_H
+#define __FIRMWARE_COREBOOT_MEMCONSOLE_H
#include <linux/types.h>
@@ -33,4 +33,4 @@ int memconsole_sysfs_init(void);
*/
void memconsole_exit(void);
-#endif /* __FIRMWARE_GOOGLE_MEMCONSOLE_H */
+#endif /* __FIRMWARE_COREBOOT_MEMCONSOLE_H */
diff --git a/drivers/firmware/google/vpd.c b/drivers/firmware/coreboot/vpd.c
similarity index 100%
rename from drivers/firmware/google/vpd.c
rename to drivers/firmware/coreboot/vpd.c
diff --git a/drivers/firmware/google/vpd_decode.c b/drivers/firmware/coreboot/vpd_decode.c
similarity index 100%
rename from drivers/firmware/google/vpd_decode.c
rename to drivers/firmware/coreboot/vpd_decode.c
diff --git a/drivers/firmware/google/vpd_decode.h b/drivers/firmware/coreboot/vpd_decode.h
similarity index 100%
rename from drivers/firmware/google/vpd_decode.h
rename to drivers/firmware/coreboot/vpd_decode.h
diff --git a/drivers/gpu/drm/sysfb/Kconfig b/drivers/gpu/drm/sysfb/Kconfig
index 2559ead6cf1f..34d3fa8b30c9 100644
--- a/drivers/gpu/drm/sysfb/Kconfig
+++ b/drivers/gpu/drm/sysfb/Kconfig
@@ -10,7 +10,7 @@ config DRM_SYSFB_HELPER
config DRM_COREBOOTDRM
tristate "Coreboot framebuffer driver"
depends on DRM && MMU
- depends on GOOGLE_FRAMEBUFFER_COREBOOT
+ depends on COREBOOT_FRAMEBUFFER
select APERTURE_HELPERS
select DRM_CLIENT_SELECTION
select DRM_GEM_SHMEM_HELPER
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH v10 4/4] firmware: coreboot: Add CFR firmware attributes driver
2026-07-28 8:20 [PATCH v10 0/4] coreboot CFR firmware attributes Sean Rhodes
` (2 preceding siblings ...)
2026-07-28 8:20 ` [PATCH v10 3/4] firmware: Rename google firmware directory to coreboot Sean Rhodes
@ 2026-07-28 8:20 ` Sean Rhodes
2026-07-28 8:34 ` sashiko-bot
3 siblings, 1 reply; 7+ messages in thread
From: Sean Rhodes @ 2026-07-28 8:20 UTC (permalink / raw)
To: chrome-platform
Cc: Corentin Chary, Luke D. Jones, Denis Benato, Hans de Goede,
Ilpo Järvinen, Prasanth Ksr, Jorge Lopez, Mark Pearson,
Derek J. Clark, Joshua Grisham, platform-driver-x86, linux-kernel,
Dell.Client.Kernel, Sean Rhodes, Huacai Chen, Michael S. Tsirkin,
Chen-Yu Tsai, Tzung-Bi Shih, Brian Norris, Julius Werner,
Thomas Zimmermann, Javier Martinez Canillas, Maarten Lankhorst,
Maxime Ripard, David Airlie, Simona Vetter, Krzysztof Kozlowski,
Bjorn Andersson, Geert Uytterhoeven, Dmitry Baryshkov,
Arnd Bergmann, Eric Biggers, Luca Weiss, Michal Simek, Sven Peter,
Florian Fainelli, Bjorn Helgaas, Takashi Sakamoto,
Danilo Krummrich, Uwe Kleine-König (The Capable Hub),
Titouan Ameline de Cadeville, Kees Cook, dri-devel, Oliver Lin
coreboot can publish a CFR tree in its coreboot table to describe
firmware setup options. Add a firmware-attributes driver for that table
entry under the coreboot firmware driver directory.
The driver exposes runtime EFI variable-backed boolean, enum and integer
settings through the firmware-attributes ABI. It only registers settings
with readable runtime EFI variables, skips suppressed, volatile,
dependency-gated and non-runtime options, and keeps read-only or inactive
options read-only in sysfs.
For settings with an APM_CNT runtime-apply record, write the EFI variable
and ask firmware to apply the setting immediately on x86. If firmware
reports a failure, restore the old EFI variable value. Settings without a
runtime apply hook, or non-x86 builds, keep the EFI variable update and
set pending_reboot.
Tested on a Star Labs Byte with firmware 26.07 and the driver built as a
module against Linux 6.17: runtime APM_CNT apply was verified with
power_led, and reboot-needed behavior was verified with debug_level.
Link: https://doc.coreboot.org/drivers/cfr.html
Link: https://doc.coreboot.org/drivers/cfr_internal.html
Signed-off-by: Sean Rhodes <sean@starlabs.systems>
---
MAINTAINERS | 6 +
drivers/firmware/coreboot/Kconfig | 14 +
drivers/firmware/coreboot/Makefile | 1 +
drivers/firmware/coreboot/coreboot-cfr.c | 1193 ++++++++++++++++++++++
4 files changed, 1214 insertions(+)
create mode 100644 drivers/firmware/coreboot/coreboot-cfr.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 8c2634a8dc13..a32e4405d20e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6666,6 +6666,12 @@ F: tools/testing/selftests/cgroup/test_hugetlb_memcg.c
F: tools/testing/selftests/cgroup/test_kmem.c
F: tools/testing/selftests/cgroup/test_memcontrol.c
+COREBOOT CFR FIRMWARE ATTRIBUTES DRIVER
+M: Sean Rhodes <sean@starlabs.systems>
+L: chrome-platform@lists.linux.dev
+S: Maintained
+F: drivers/firmware/coreboot/coreboot-cfr.c
+
CORETEMP HARDWARE MONITORING DRIVER
L: linux-hwmon@vger.kernel.org
S: Orphan
diff --git a/drivers/firmware/coreboot/Kconfig b/drivers/firmware/coreboot/Kconfig
index d273bd836245..30ee5a814a88 100644
--- a/drivers/firmware/coreboot/Kconfig
+++ b/drivers/firmware/coreboot/Kconfig
@@ -49,6 +49,20 @@ config COREBOOT_TABLE
device tree node /firmware/coreboot.
If unsure say N.
+config COREBOOT_CFR
+ tristate "coreboot CFR firmware attributes"
+ depends on EFI
+ depends on COREBOOT_TABLE
+ select CRC32
+ select FW_ATTR_CLASS
+ help
+ This driver parses the coreboot CFR table and exposes runtime EFI
+ variable-backed options through the firmware-attributes sysfs
+ interface.
+
+ If you have a system running coreboot with CFR runtime
+ configuration support, say Y or M here.
+
config COREBOOT_MEMCONSOLE_COMMON
tristate
depends on GOOGLE_MEMCONSOLE_X86_LEGACY || COREBOOT_MEMCONSOLE
diff --git a/drivers/firmware/coreboot/Makefile b/drivers/firmware/coreboot/Makefile
index e681f274417a..a08d167a95a8 100644
--- a/drivers/firmware/coreboot/Makefile
+++ b/drivers/firmware/coreboot/Makefile
@@ -2,6 +2,7 @@
obj-$(CONFIG_GOOGLE_SMI) += gsmi.o
obj-$(CONFIG_COREBOOT_TABLE) += coreboot_table.o
+obj-$(CONFIG_COREBOOT_CFR) += coreboot-cfr.o
obj-$(CONFIG_COREBOOT_FRAMEBUFFER) += framebuffer-coreboot.o
obj-$(CONFIG_COREBOOT_MEMCONSOLE_COMMON) += memconsole.o
obj-$(CONFIG_COREBOOT_MEMCONSOLE) += memconsole-coreboot.o
diff --git a/drivers/firmware/coreboot/coreboot-cfr.c b/drivers/firmware/coreboot/coreboot-cfr.c
new file mode 100644
index 000000000000..21b06aa36311
--- /dev/null
+++ b/drivers/firmware/coreboot/coreboot-cfr.c
@@ -0,0 +1,1193 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * coreboot CFR firmware attributes driver.
+ *
+ * Parses LB_TAG_CFR_ROOT records from the coreboot table and exposes
+ * runtime EFI variable-backed options through the firmware-attributes class.
+ */
+
+#include <linux/array_size.h>
+#include <linux/bitops.h>
+#include <linux/cleanup.h>
+#include <linux/compiler_attributes.h>
+#include <linux/container_of.h>
+#include <linux/crc32.h>
+#include <linux/ctype.h>
+#include <linux/device.h>
+#include <linux/device-id/coreboot.h>
+#include <linux/efi.h>
+#include <linux/err.h>
+#include <linux/firmware_attributes.h>
+#include <linux/io.h>
+#include <linux/kdev_t.h>
+#include <linux/kobject.h>
+#include <linux/kstrtox.h>
+#include <linux/limits.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include "coreboot_table.h"
+
+#define DRIVER_NAME "coreboot-cfr"
+
+#define LB_TAG_CFR_ROOT 0x47
+#define CFR_VERSION 0
+
+enum cfr_tags {
+ CFR_TAG_OPTION_FORM = 1,
+ CFR_TAG_ENUM_VALUE = 2,
+ CFR_TAG_OPTION_ENUM = 3,
+ CFR_TAG_OPTION_NUMBER = 4,
+ CFR_TAG_OPTION_BOOL = 5,
+ CFR_TAG_VARCHAR_OPT_NAME = 7,
+ CFR_TAG_VARCHAR_UI_NAME = 8,
+ CFR_TAG_RUNTIME_APPLY = 13,
+};
+
+enum cfr_option_flags {
+ CFR_OPTFLAG_READONLY = BIT(0),
+ CFR_OPTFLAG_INACTIVE = BIT(1),
+ CFR_OPTFLAG_SUPPRESS = BIT(2),
+ CFR_OPTFLAG_VOLATILE = BIT(3),
+ CFR_OPTFLAG_RUNTIME = BIT(4),
+};
+
+enum cfr_runtime_apply_method {
+ CFR_RUNTIME_APPLY_NONE = 0,
+ CFR_RUNTIME_APPLY_APM_CNT = 1,
+};
+
+struct lb_cfr {
+ u32 tag;
+ u32 size;
+ u32 version;
+ u32 checksum;
+} __packed;
+
+struct lb_cfr_varbinary {
+ u32 tag;
+ u32 size;
+ u32 data_length;
+} __packed;
+
+struct lb_cfr_enum_value {
+ u32 tag;
+ u32 size;
+ u32 value;
+} __packed;
+
+struct lb_cfr_runtime_apply {
+ u32 tag;
+ u32 size;
+ u32 method;
+ u32 id;
+} __packed;
+
+struct lb_cfr_numeric_option {
+ u32 tag;
+ u32 size;
+ cb_u64 object_id;
+ cb_u64 dependency_id;
+ u32 flags;
+ u32 default_value;
+ u32 min;
+ u32 max;
+ u32 step;
+ u32 display_flags;
+} __packed;
+
+struct lb_cfr_option_form {
+ u32 tag;
+ u32 size;
+ cb_u64 object_id;
+ cb_u64 dependency_id;
+ u32 flags;
+} __packed;
+
+#define COREBOOT_CFR_OPT_SKIP_FLAGS \
+ (CFR_OPTFLAG_SUPPRESS | CFR_OPTFLAG_VOLATILE)
+
+#define COREBOOT_CFR_OPT_READ_ONLY_FLAGS \
+ (CFR_OPTFLAG_READONLY | CFR_OPTFLAG_INACTIVE)
+
+#define COREBOOT_CFR_EFI_ATTRS \
+ (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | \
+ EFI_VARIABLE_RUNTIME_ACCESS)
+
+#define COREBOOT_CFR_APM_CNT_PORT 0xb2
+#define COREBOOT_CFR_APM_STS_PORT 0xb3
+#define COREBOOT_CFR_APM_APPLY_CMD 0xe3
+#define COREBOOT_CFR_MAX_FORM_DEPTH 16
+
+static efi_guid_t coreboot_cfr_guid = EFI_GUID(0xceae4c1d, 0x335b, 0x4685,
+ 0xa4, 0xa0, 0xfc, 0x4a,
+ 0x94, 0xee, 0xa0, 0x85);
+
+enum coreboot_cfr_setting_type {
+ COREBOOT_CFR_SETTING_ENUM,
+ COREBOOT_CFR_SETTING_NUMBER,
+ COREBOOT_CFR_SETTING_BOOL,
+};
+
+struct coreboot_cfr_enum {
+ char *label;
+ u32 value;
+};
+
+struct coreboot_cfr_setting {
+ struct kobject kobj;
+ struct list_head node;
+ struct coreboot_cfr_drvdata *drvdata;
+ enum coreboot_cfr_setting_type type;
+ char *name;
+ char *display_name;
+ struct coreboot_cfr_enum *values;
+ unsigned int n_values;
+ u32 default_value;
+ u32 min;
+ u32 max;
+ u32 step;
+ u32 runtime_apply_method;
+ u32 runtime_apply_id;
+ bool read_only;
+};
+
+struct coreboot_cfr_drvdata {
+ struct device *class_dev;
+ struct kset *attrs_kset;
+ struct list_head settings;
+ /* Serializes EFI variable writes and the matching runtime apply hook. */
+ struct mutex lock;
+ bool efi_writes_supported;
+ bool pending_reboot;
+};
+
+struct coreboot_cfr_iterator {
+ const u8 *cursor;
+ size_t remaining;
+};
+
+static struct coreboot_cfr_setting *to_coreboot_cfr_setting(struct kobject *kobj)
+{
+ return container_of(kobj, struct coreboot_cfr_setting, kobj);
+}
+
+static bool coreboot_cfr_string_is_valid_name(const char *name)
+{
+ return name && name[0] && !strchr(name, '/');
+}
+
+static char *coreboot_cfr_string_dup(const struct lb_cfr_varbinary *str)
+{
+ const char *data = (const char *)(str + 1);
+ size_t len = str->data_length;
+
+ if (len && !data[len - 1])
+ len--;
+
+ return kmemdup_nul(data, len, GFP_KERNEL);
+}
+
+static const struct coreboot_table_entry *
+coreboot_cfr_next_entry(struct coreboot_cfr_iterator *iterator)
+{
+ const struct coreboot_table_entry *entry;
+
+ if (!iterator->remaining)
+ return NULL;
+
+ if (iterator->remaining < sizeof(*entry))
+ return ERR_PTR(-EINVAL);
+
+ entry = (const struct coreboot_table_entry *)iterator->cursor;
+ if (entry->size < sizeof(*entry) || entry->size > iterator->remaining)
+ return ERR_PTR(-EINVAL);
+
+ iterator->cursor += entry->size;
+ iterator->remaining -= entry->size;
+
+ return entry;
+}
+
+static const struct coreboot_table_entry *
+coreboot_cfr_child_entry(const void *base, size_t len, u32 tag)
+{
+ struct coreboot_cfr_iterator iterator = {
+ .cursor = base,
+ .remaining = len,
+ };
+ const struct coreboot_table_entry *entry;
+
+ for (;;) {
+ entry = coreboot_cfr_next_entry(&iterator);
+ if (!entry || IS_ERR(entry))
+ return entry;
+
+ if (entry->tag == tag)
+ return entry;
+ }
+}
+
+static const struct lb_cfr_varbinary *
+coreboot_cfr_child_string(const void *base, size_t len, u32 tag)
+{
+ const struct lb_cfr_varbinary *str;
+ const struct coreboot_table_entry *entry;
+
+ entry = coreboot_cfr_child_entry(base, len, tag);
+ if (IS_ERR(entry))
+ return ERR_CAST(entry);
+ if (!entry)
+ return NULL;
+
+ if (entry->size < sizeof(*str))
+ return ERR_PTR(-EINVAL);
+
+ str = (const struct lb_cfr_varbinary *)entry;
+ if (str->data_length > entry->size - sizeof(*str))
+ return ERR_PTR(-EINVAL);
+
+ return str;
+}
+
+static const struct lb_cfr_runtime_apply *
+coreboot_cfr_child_runtime_apply(const void *base, size_t len)
+{
+ const struct lb_cfr_runtime_apply *runtime_apply;
+ const struct coreboot_table_entry *entry;
+
+ entry = coreboot_cfr_child_entry(base, len, CFR_TAG_RUNTIME_APPLY);
+ if (IS_ERR(entry))
+ return ERR_CAST(entry);
+ if (!entry)
+ return NULL;
+
+ if (entry->size < sizeof(*runtime_apply))
+ return ERR_PTR(-EINVAL);
+
+ runtime_apply = (const struct lb_cfr_runtime_apply *)entry;
+ if (runtime_apply->method == CFR_RUNTIME_APPLY_APM_CNT &&
+ runtime_apply->id > U8_MAX)
+ return ERR_PTR(-EINVAL);
+
+ return runtime_apply;
+}
+
+static efi_char16_t *coreboot_cfr_efi_name(const char *name)
+{
+ size_t len, i;
+
+ len = strlen(name);
+ if (len >= EFI_VAR_NAME_LEN)
+ return ERR_PTR(-ENAMETOOLONG);
+
+ efi_char16_t *efi_name __free(kfree) =
+ kcalloc(len + 1, sizeof(*efi_name), GFP_KERNEL);
+ if (!efi_name)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < len; i++) {
+ if (!isascii(name[i]))
+ return ERR_PTR(-EINVAL);
+ efi_name[i] = name[i];
+ }
+
+ return no_free_ptr(efi_name);
+}
+
+/* Caller must hold the efivar lock. */
+static int coreboot_cfr_read_efi_value(efi_char16_t *efi_name, u32 *value,
+ u32 *attrs)
+{
+ unsigned long size = sizeof(__le32);
+ efi_status_t status;
+ __le32 data;
+ u32 attr;
+
+ status = efivar_get_variable(efi_name, &coreboot_cfr_guid, &attr,
+ &size, &data);
+ if (status != EFI_SUCCESS)
+ return efi_status_to_err(status);
+
+ if (size != sizeof(data))
+ return -EINVAL;
+
+ if (!(attr & EFI_VARIABLE_RUNTIME_ACCESS))
+ return -EOPNOTSUPP;
+
+ *value = le32_to_cpu(data);
+ if (attrs)
+ *attrs = attr;
+
+ return 0;
+}
+
+static int coreboot_cfr_read_value(const struct coreboot_cfr_setting *setting,
+ u32 *value, u32 *attrs)
+{
+ efi_char16_t *efi_name __free(kfree) =
+ coreboot_cfr_efi_name(setting->name);
+ int ret;
+
+ if (IS_ERR(efi_name))
+ return PTR_ERR(no_free_ptr(efi_name));
+
+ ret = efivar_lock();
+ if (ret)
+ return ret;
+
+ ret = coreboot_cfr_read_efi_value(efi_name, value, attrs);
+ efivar_unlock();
+
+ return ret;
+}
+
+/* Caller must hold the efivar lock. */
+static int coreboot_cfr_write_efi_value(efi_char16_t *efi_name, u32 value,
+ u32 attrs)
+{
+ efi_status_t status;
+ __le32 data;
+
+ if (!efivar_supports_writes())
+ return -EROFS;
+
+ data = cpu_to_le32(value);
+ status = efivar_set_variable_locked(efi_name, &coreboot_cfr_guid, attrs,
+ sizeof(data), &data, false);
+ if (status != EFI_SUCCESS)
+ return efi_status_to_err(status);
+
+ return 0;
+}
+
+static int coreboot_cfr_apply_runtime(struct coreboot_cfr_setting *setting)
+{
+#ifdef CONFIG_X86
+ u8 status;
+
+ if (setting->runtime_apply_method != CFR_RUNTIME_APPLY_APM_CNT)
+ return -EOPNOTSUPP;
+
+ outb((u8)setting->runtime_apply_id, COREBOOT_CFR_APM_STS_PORT);
+ outb(COREBOOT_CFR_APM_APPLY_CMD, COREBOOT_CFR_APM_CNT_PORT);
+ status = inb(COREBOOT_CFR_APM_STS_PORT);
+ if (status)
+ return -EIO;
+
+ return 0;
+#else
+ return -EOPNOTSUPP;
+#endif
+}
+
+static int coreboot_cfr_write_value(struct coreboot_cfr_setting *setting,
+ u32 value)
+{
+ efi_char16_t *efi_name __free(kfree) = NULL;
+ u32 attrs;
+ u32 old;
+ int restore_ret;
+ int ret;
+
+ if (setting->read_only)
+ return -EACCES;
+
+ efi_name = coreboot_cfr_efi_name(setting->name);
+ if (IS_ERR(efi_name))
+ return PTR_ERR(no_free_ptr(efi_name));
+
+ guard(mutex)(&setting->drvdata->lock);
+
+ ret = efivar_lock();
+ if (ret)
+ return ret;
+
+ ret = coreboot_cfr_read_efi_value(efi_name, &old, &attrs);
+ if (ret)
+ goto out_unlock_efi;
+
+ if ((attrs & COREBOOT_CFR_EFI_ATTRS) != COREBOOT_CFR_EFI_ATTRS) {
+ ret = -EOPNOTSUPP;
+ goto out_unlock_efi;
+ }
+
+ if (old == value)
+ goto out_unlock_efi;
+
+ ret = coreboot_cfr_write_efi_value(efi_name, value, attrs);
+ if (ret)
+ goto out_unlock_efi;
+
+ ret = coreboot_cfr_apply_runtime(setting);
+ if (ret == -EOPNOTSUPP) {
+ /* EFI changed; firmware will consume it after reboot. */
+ setting->drvdata->pending_reboot = true;
+ ret = 0;
+ } else if (ret) {
+ restore_ret = coreboot_cfr_write_efi_value(efi_name, old, attrs);
+ if (restore_ret) {
+ setting->drvdata->pending_reboot = true;
+ ret = restore_ret;
+ } else {
+ goto out_unlock_efi;
+ }
+ }
+
+ efivar_unlock();
+ kobject_uevent(&setting->drvdata->class_dev->kobj, KOBJ_CHANGE);
+ return ret;
+
+out_unlock_efi:
+ efivar_unlock();
+ return ret;
+}
+
+static const char *
+coreboot_cfr_label_from_value(const struct coreboot_cfr_setting *setting,
+ u32 value)
+{
+ unsigned int i;
+
+ for (i = 0; i < setting->n_values; i++) {
+ if (setting->values[i].value == value)
+ return setting->values[i].label;
+ }
+
+ return NULL;
+}
+
+static int coreboot_cfr_parse_value(struct coreboot_cfr_setting *setting,
+ const char *label, u32 *value_out)
+{
+ unsigned int i;
+
+ for (i = 0; i < setting->n_values; i++) {
+ if (!sysfs_streq(label, setting->values[i].label))
+ continue;
+
+ *value_out = setting->values[i].value;
+ return 0;
+ }
+
+ return kstrtou32(label, 0, value_out);
+}
+
+static bool coreboot_cfr_value_is_valid(struct coreboot_cfr_setting *setting,
+ u32 value)
+{
+ u32 delta;
+
+ if (setting->type != COREBOOT_CFR_SETTING_NUMBER) {
+ /* Enum and bool values are valid only if they have a label. */
+ return coreboot_cfr_label_from_value(setting, value);
+ }
+
+ if (value < setting->min || value > setting->max)
+ return false;
+
+ if (!setting->step)
+ return true;
+
+ delta = value - setting->min;
+ return delta % setting->step == 0;
+}
+
+static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+
+ if (setting->type == COREBOOT_CFR_SETTING_NUMBER)
+ return sysfs_emit(buf, "integer\n");
+
+ return sysfs_emit(buf, "enumeration\n");
+}
+
+static ssize_t display_name_language_code_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return sysfs_emit(buf, "en_US.UTF-8\n");
+}
+
+static ssize_t display_name_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+
+ return sysfs_emit(buf, "%s\n", setting->display_name);
+}
+
+static ssize_t possible_values_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+ ssize_t len = 0;
+ unsigned int i;
+
+ for (i = 0; i < setting->n_values; i++) {
+ len += sysfs_emit_at(buf, len, "%s%s", i ? ";" : "",
+ setting->values[i].label);
+ }
+
+ len += sysfs_emit_at(buf, len, "\n");
+ return len;
+}
+
+static ssize_t min_value_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+
+ return sysfs_emit(buf, "%u\n", setting->min);
+}
+
+static ssize_t max_value_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+
+ return sysfs_emit(buf, "%u\n", setting->max);
+}
+
+static ssize_t scalar_increment_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+
+ return sysfs_emit(buf, "%u\n", setting->step);
+}
+
+static ssize_t default_value_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+ const char *label;
+
+ if (setting->type == COREBOOT_CFR_SETTING_NUMBER)
+ return sysfs_emit(buf, "%u\n", setting->default_value);
+
+ label = coreboot_cfr_label_from_value(setting, setting->default_value);
+ if (!label)
+ return sysfs_emit(buf, "%u\n", setting->default_value);
+
+ return sysfs_emit(buf, "%s\n", label);
+}
+
+static ssize_t current_value_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+ const char *label;
+ u32 value;
+ int ret;
+
+ ret = coreboot_cfr_read_value(setting, &value, NULL);
+ if (ret)
+ return ret;
+
+ if (setting->type == COREBOOT_CFR_SETTING_NUMBER)
+ return sysfs_emit(buf, "%u\n", value);
+
+ label = coreboot_cfr_label_from_value(setting, value);
+ if (!label)
+ return -EINVAL;
+
+ return sysfs_emit(buf, "%s\n", label);
+}
+
+static ssize_t current_value_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+ u32 value;
+ int ret;
+
+ ret = coreboot_cfr_parse_value(setting, buf, &value);
+ if (ret)
+ return ret;
+
+ if (!coreboot_cfr_value_is_valid(setting, value))
+ return -EINVAL;
+
+ ret = coreboot_cfr_write_value(setting, value);
+ if (ret)
+ return ret;
+
+ return count;
+}
+
+static struct kobj_attribute type_attr = __ATTR_RO(type);
+static struct kobj_attribute display_name_language_code_attr =
+ __ATTR_RO(display_name_language_code);
+static struct kobj_attribute display_name_attr = __ATTR_RO(display_name);
+static struct kobj_attribute possible_values_attr = __ATTR_RO(possible_values);
+static struct kobj_attribute min_value_attr = __ATTR_RO(min_value);
+static struct kobj_attribute max_value_attr = __ATTR_RO(max_value);
+static struct kobj_attribute scalar_increment_attr = __ATTR_RO(scalar_increment);
+static struct kobj_attribute default_value_attr = __ATTR_RO(default_value);
+static struct kobj_attribute current_value_attr = __ATTR_RW(current_value);
+
+static struct attribute *coreboot_cfr_setting_attrs[] = {
+ &type_attr.attr,
+ &display_name_language_code_attr.attr,
+ &display_name_attr.attr,
+ &possible_values_attr.attr,
+ &min_value_attr.attr,
+ &max_value_attr.attr,
+ &scalar_increment_attr.attr,
+ &default_value_attr.attr,
+ ¤t_value_attr.attr,
+ NULL,
+};
+
+static umode_t coreboot_cfr_attr_is_visible(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ struct coreboot_cfr_setting *setting = to_coreboot_cfr_setting(kobj);
+
+ if (setting->type == COREBOOT_CFR_SETTING_NUMBER &&
+ attr == &possible_values_attr.attr)
+ return 0;
+
+ if (setting->type != COREBOOT_CFR_SETTING_NUMBER &&
+ (attr == &min_value_attr.attr || attr == &max_value_attr.attr ||
+ attr == &scalar_increment_attr.attr))
+ return 0;
+
+ if (setting->read_only && attr == ¤t_value_attr.attr)
+ return 0444;
+
+ return attr->mode;
+}
+
+static const struct attribute_group coreboot_cfr_setting_group = {
+ .attrs = coreboot_cfr_setting_attrs,
+ .is_visible = coreboot_cfr_attr_is_visible,
+};
+
+static void coreboot_cfr_free_setting(struct coreboot_cfr_setting *setting)
+{
+ unsigned int i;
+
+ for (i = 0; i < setting->n_values; i++)
+ kfree(setting->values[i].label);
+
+ kfree(setting->values);
+ kfree(setting->display_name);
+ kfree(setting->name);
+ kfree(setting);
+}
+
+static void coreboot_cfr_setting_release(struct kobject *kobj)
+{
+ coreboot_cfr_free_setting(to_coreboot_cfr_setting(kobj));
+}
+
+static const struct kobj_type coreboot_cfr_setting_ktype = {
+ .release = coreboot_cfr_setting_release,
+ .sysfs_ops = &kobj_sysfs_ops,
+};
+
+static ssize_t pending_reboot_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ struct device *dev = kobj_to_dev(kobj->parent);
+ struct coreboot_cfr_drvdata *data;
+
+ data = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%d\n", data->pending_reboot);
+}
+
+static struct kobj_attribute pending_reboot_attr = __ATTR_RO(pending_reboot);
+
+static int coreboot_cfr_copy_bool_values(struct coreboot_cfr_setting *setting)
+{
+ static const struct coreboot_cfr_enum bool_values[] = {
+ { .label = "Disabled", .value = 0 },
+ { .label = "Enabled", .value = 1 },
+ };
+ unsigned int i;
+
+ setting->values = kcalloc(ARRAY_SIZE(bool_values), sizeof(*setting->values),
+ GFP_KERNEL);
+ if (!setting->values)
+ return -ENOMEM;
+
+ for (i = 0; i < ARRAY_SIZE(bool_values); i++) {
+ setting->values[i].label = kstrdup(bool_values[i].label,
+ GFP_KERNEL);
+ if (!setting->values[i].label)
+ return -ENOMEM;
+ setting->values[i].value = bool_values[i].value;
+ setting->n_values++;
+ }
+
+ return 0;
+}
+
+static int coreboot_cfr_count_enum_values(const void *base, size_t len)
+{
+ struct coreboot_cfr_iterator iterator = {
+ .cursor = base,
+ .remaining = len,
+ };
+ const struct coreboot_table_entry *entry;
+ int count = 0;
+
+ for (;;) {
+ entry = coreboot_cfr_next_entry(&iterator);
+ if (IS_ERR(entry))
+ return PTR_ERR(entry);
+ if (!entry)
+ return count;
+
+ if (entry->tag == CFR_TAG_ENUM_VALUE)
+ count++;
+ }
+}
+
+static int coreboot_cfr_copy_enum_values(struct coreboot_cfr_setting *setting,
+ const void *base, size_t len)
+{
+ struct coreboot_cfr_iterator iterator = {
+ .cursor = base,
+ .remaining = len,
+ };
+ const struct lb_cfr_enum_value *enum_value;
+ const struct lb_cfr_varbinary *label;
+ const struct coreboot_table_entry *entry;
+ struct coreboot_cfr_enum *value;
+ int count;
+
+ count = coreboot_cfr_count_enum_values(base, len);
+ if (count <= 0)
+ return count ?: -EINVAL;
+
+ setting->values = kcalloc(count, sizeof(*setting->values), GFP_KERNEL);
+ if (!setting->values)
+ return -ENOMEM;
+
+ for (;;) {
+ entry = coreboot_cfr_next_entry(&iterator);
+ if (IS_ERR(entry))
+ return PTR_ERR(entry);
+ if (!entry)
+ return 0;
+
+ if (entry->tag != CFR_TAG_ENUM_VALUE)
+ continue;
+
+ if (entry->size < sizeof(*enum_value))
+ return -EINVAL;
+
+ enum_value = (const struct lb_cfr_enum_value *)entry;
+ label = coreboot_cfr_child_string(enum_value + 1,
+ enum_value->size - sizeof(*enum_value),
+ CFR_TAG_VARCHAR_UI_NAME);
+ if (IS_ERR(label))
+ return PTR_ERR(label);
+ if (!label)
+ return -EINVAL;
+
+ value = &setting->values[setting->n_values];
+ value->label = coreboot_cfr_string_dup(label);
+ if (!value->label)
+ return -ENOMEM;
+
+ value->value = enum_value->value;
+ setting->n_values++;
+ }
+}
+
+static bool
+coreboot_cfr_possible_values_fit(const struct coreboot_cfr_setting *setting)
+{
+ size_t len = 1; /* Trailing newline. */
+ size_t label_len;
+ unsigned int i;
+
+ for (i = 0; i < setting->n_values; i++) {
+ if (len >= PAGE_SIZE)
+ return false;
+
+ if (i)
+ len++;
+
+ label_len = strlen(setting->values[i].label);
+ if (label_len >= PAGE_SIZE - len)
+ return false;
+
+ len += label_len;
+ }
+
+ return true;
+}
+
+static int coreboot_cfr_setting_is_usable(struct coreboot_cfr_setting *setting)
+{
+ u32 value;
+ int ret;
+
+ ret = coreboot_cfr_read_value(setting, &value, NULL);
+ if (ret)
+ return ret;
+
+ if (!coreboot_cfr_value_is_valid(setting, value))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int coreboot_cfr_register_setting(struct coreboot_cfr_drvdata *data,
+ struct coreboot_cfr_setting *setting)
+{
+ int ret;
+
+ ret = kobject_init_and_add(&setting->kobj, &coreboot_cfr_setting_ktype,
+ &data->attrs_kset->kobj, "%s", setting->name);
+ if (ret)
+ goto err_put_kobj;
+
+ ret = sysfs_create_group(&setting->kobj, &coreboot_cfr_setting_group);
+ if (ret)
+ goto err_put_kobj;
+
+ list_add_tail(&setting->node, &data->settings);
+ return 0;
+
+err_put_kobj:
+ kobject_put(&setting->kobj);
+ return ret;
+}
+
+static int coreboot_cfr_add_numeric_option(struct coreboot_cfr_drvdata *data,
+ const struct lb_cfr_numeric_option *option,
+ bool parent_read_only)
+{
+ const struct lb_cfr_varbinary *name;
+ const struct lb_cfr_varbinary *display_name;
+ const struct lb_cfr_runtime_apply *runtime_apply;
+ const void *child_base = option + 1;
+ struct coreboot_cfr_setting *setting;
+ size_t child_len = option->size - sizeof(*option);
+ int ret;
+
+ if (!(option->flags & CFR_OPTFLAG_RUNTIME))
+ return 0;
+
+ if (option->flags & COREBOOT_CFR_OPT_SKIP_FLAGS)
+ return 0;
+
+ if (option->dependency_id)
+ return 0;
+
+ setting = kzalloc_obj(*setting, GFP_KERNEL);
+ if (!setting)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&setting->node);
+ setting->drvdata = data;
+ setting->default_value = option->default_value;
+ setting->min = option->min;
+ setting->max = option->max;
+ setting->step = option->step ?: 1;
+ setting->read_only =
+ (option->flags & COREBOOT_CFR_OPT_READ_ONLY_FLAGS) ||
+ !data->efi_writes_supported || parent_read_only;
+
+ runtime_apply = coreboot_cfr_child_runtime_apply(child_base, child_len);
+ if (IS_ERR(runtime_apply)) {
+ ret = PTR_ERR(runtime_apply);
+ goto err_put_setting;
+ }
+
+ if (runtime_apply && runtime_apply->method == CFR_RUNTIME_APPLY_APM_CNT) {
+ setting->runtime_apply_method = runtime_apply->method;
+ setting->runtime_apply_id = runtime_apply->id;
+ }
+
+ name = coreboot_cfr_child_string(child_base, child_len,
+ CFR_TAG_VARCHAR_OPT_NAME);
+ if (IS_ERR(name)) {
+ ret = PTR_ERR(name);
+ goto err_put_setting;
+ }
+ if (!name) {
+ ret = -EINVAL;
+ goto err_put_setting;
+ }
+
+ setting->name = coreboot_cfr_string_dup(name);
+ if (!setting->name) {
+ ret = -ENOMEM;
+ goto err_put_setting;
+ }
+
+ if (!coreboot_cfr_string_is_valid_name(setting->name)) {
+ ret = -EINVAL;
+ goto err_put_setting;
+ }
+
+ display_name = coreboot_cfr_child_string(child_base, child_len,
+ CFR_TAG_VARCHAR_UI_NAME);
+ if (IS_ERR(display_name)) {
+ ret = PTR_ERR(display_name);
+ goto err_put_setting;
+ }
+ if (display_name)
+ setting->display_name = coreboot_cfr_string_dup(display_name);
+ else
+ setting->display_name = kstrdup(setting->name, GFP_KERNEL);
+ if (!setting->display_name) {
+ ret = -ENOMEM;
+ goto err_put_setting;
+ }
+
+ switch (option->tag) {
+ case CFR_TAG_OPTION_BOOL:
+ setting->type = COREBOOT_CFR_SETTING_BOOL;
+ setting->min = 0;
+ setting->max = 1;
+ setting->step = 1;
+ ret = coreboot_cfr_copy_bool_values(setting);
+ break;
+ case CFR_TAG_OPTION_ENUM:
+ setting->type = COREBOOT_CFR_SETTING_ENUM;
+ ret = coreboot_cfr_copy_enum_values(setting, child_base,
+ child_len);
+ break;
+ case CFR_TAG_OPTION_NUMBER:
+ setting->type = COREBOOT_CFR_SETTING_NUMBER;
+ if (!setting->min && !setting->max)
+ setting->max = U32_MAX;
+ else if (setting->max < setting->min)
+ setting->max = U32_MAX;
+ ret = 0;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ if (ret)
+ goto err_put_setting;
+ /* possible_values must be returned completely in one sysfs read. */
+ if (setting->type != COREBOOT_CFR_SETTING_NUMBER &&
+ !coreboot_cfr_possible_values_fit(setting)) {
+ ret = 0;
+ goto err_put_setting;
+ }
+
+ ret = coreboot_cfr_setting_is_usable(setting);
+ if (ret) {
+ /*
+ * CFR may describe options without a matching, readable runtime
+ * EFI variable. Skip those, but propagate transient EFI failures.
+ */
+ if (ret == -ENOENT || ret == -EINVAL || ret == -EOPNOTSUPP ||
+ ret == -ENAMETOOLONG)
+ ret = 0;
+ goto err_put_setting;
+ }
+
+ /* The kobject release callback owns setting after this call. */
+ return coreboot_cfr_register_setting(data, setting);
+
+err_put_setting:
+ coreboot_cfr_free_setting(setting);
+ return ret;
+}
+
+static int coreboot_cfr_parse_records(struct coreboot_cfr_drvdata *data,
+ const void *base, size_t len,
+ unsigned int depth,
+ bool parent_read_only)
+{
+ struct coreboot_cfr_iterator iterator = {
+ .cursor = base,
+ .remaining = len,
+ };
+ const struct lb_cfr_option_form *form;
+ const struct lb_cfr_numeric_option *option;
+ const struct coreboot_table_entry *entry;
+ const void *child_base;
+ size_t child_len;
+ int ret;
+
+ for (;;) {
+ entry = coreboot_cfr_next_entry(&iterator);
+ if (IS_ERR(entry))
+ return PTR_ERR(entry);
+ if (!entry)
+ return 0;
+
+ switch (entry->tag) {
+ case CFR_TAG_OPTION_FORM:
+ if (entry->size < sizeof(struct lb_cfr_option_form))
+ return -EINVAL;
+
+ form = (const struct lb_cfr_option_form *)entry;
+ if (form->dependency_id ||
+ form->flags & CFR_OPTFLAG_SUPPRESS)
+ break;
+
+ if (depth >= COREBOOT_CFR_MAX_FORM_DEPTH)
+ return -E2BIG;
+
+ child_base = form + 1;
+ child_len = entry->size - sizeof(struct lb_cfr_option_form);
+ ret = coreboot_cfr_parse_records(data, child_base,
+ child_len, depth + 1,
+ parent_read_only ||
+ (form->flags &
+ COREBOOT_CFR_OPT_READ_ONLY_FLAGS));
+ if (ret)
+ return ret;
+ break;
+ case CFR_TAG_OPTION_ENUM:
+ case CFR_TAG_OPTION_NUMBER:
+ case CFR_TAG_OPTION_BOOL:
+ option = (const struct lb_cfr_numeric_option *)entry;
+ if (entry->size < sizeof(*option))
+ return -EINVAL;
+ ret = coreboot_cfr_add_numeric_option(data, option,
+ parent_read_only);
+ if (ret)
+ return ret;
+ break;
+ default:
+ /* Ignore unsupported, child-only and future record types. */
+ break;
+ }
+ }
+}
+
+static void coreboot_cfr_unregister_settings(struct coreboot_cfr_drvdata *data)
+{
+ struct coreboot_cfr_setting *setting, *tmp;
+
+ list_for_each_entry_safe(setting, tmp, &data->settings, node) {
+ sysfs_remove_group(&setting->kobj, &coreboot_cfr_setting_group);
+ list_del(&setting->node);
+ kobject_put(&setting->kobj);
+ }
+}
+
+static int coreboot_cfr_probe(struct coreboot_device *dev)
+{
+ const struct lb_cfr *root = (const struct lb_cfr *)dev->raw;
+ struct coreboot_cfr_drvdata *data;
+ size_t payload_len;
+ int ret;
+
+ if (dev->entry.size < sizeof(*root))
+ return -EINVAL;
+
+ if (root->tag != LB_TAG_CFR_ROOT || root->version != CFR_VERSION)
+ return -EINVAL;
+
+ if (root->size < sizeof(*root) || root->size > dev->entry.size)
+ return -EINVAL;
+
+ payload_len = root->size - sizeof(*root);
+ if (crc32_be(0, root + 1, payload_len) != root->checksum)
+ return -EBADMSG;
+
+ if (!efivar_is_available())
+ return -EPROBE_DEFER;
+
+ data = devm_kzalloc(&dev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ ret = efivar_lock();
+ if (ret)
+ return ret;
+ data->efi_writes_supported = efivar_supports_writes();
+ efivar_unlock();
+
+ INIT_LIST_HEAD(&data->settings);
+ ret = devm_mutex_init(&dev->dev, &data->lock);
+ if (ret)
+ return ret;
+
+ dev_set_drvdata(&dev->dev, data);
+
+ data->class_dev = device_create(&firmware_attributes_class, NULL,
+ MKDEV(0, 0), NULL, DRIVER_NAME);
+ if (IS_ERR(data->class_dev))
+ return PTR_ERR(data->class_dev);
+ dev_set_drvdata(data->class_dev, data);
+
+ data->attrs_kset = kset_create_and_add("attributes", NULL,
+ &data->class_dev->kobj);
+ if (!data->attrs_kset) {
+ ret = -ENOMEM;
+ goto err_unregister_dev;
+ }
+
+ ret = sysfs_create_file(&data->attrs_kset->kobj,
+ &pending_reboot_attr.attr);
+ if (ret)
+ goto err_unregister_attrs;
+
+ ret = coreboot_cfr_parse_records(data, root + 1, payload_len, 0, false);
+ if (ret)
+ goto err_unregister_settings;
+
+ if (list_empty(&data->settings)) {
+ ret = -ENODEV;
+ goto err_unregister_settings;
+ }
+
+ return 0;
+
+err_unregister_settings:
+ coreboot_cfr_unregister_settings(data);
+ sysfs_remove_file(&data->attrs_kset->kobj, &pending_reboot_attr.attr);
+err_unregister_attrs:
+ kset_unregister(data->attrs_kset);
+err_unregister_dev:
+ device_unregister(data->class_dev);
+ return ret;
+}
+
+static void coreboot_cfr_remove(struct coreboot_device *dev)
+{
+ struct coreboot_cfr_drvdata *data = dev_get_drvdata(&dev->dev);
+
+ coreboot_cfr_unregister_settings(data);
+ sysfs_remove_file(&data->attrs_kset->kobj, &pending_reboot_attr.attr);
+ kset_unregister(data->attrs_kset);
+ device_unregister(data->class_dev);
+}
+
+static const struct coreboot_device_id coreboot_cfr_ids[] = {
+ { .tag = LB_TAG_CFR_ROOT },
+ { }
+};
+MODULE_DEVICE_TABLE(coreboot, coreboot_cfr_ids);
+
+static struct coreboot_driver coreboot_cfr_driver = {
+ .probe = coreboot_cfr_probe,
+ .remove = coreboot_cfr_remove,
+ .drv = {
+ .name = DRIVER_NAME,
+ },
+ .id_table = coreboot_cfr_ids,
+};
+module_coreboot_driver(coreboot_cfr_driver);
+
+MODULE_AUTHOR("Sean Rhodes <sean@starlabs.systems>");
+MODULE_DESCRIPTION("coreboot CFR firmware attributes driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("EFIVAR");
^ permalink raw reply related [flat|nested] 7+ messages in thread