|
|
@@ -88,160 +88,7 @@ config PREVENT_FIRMWARE_BUILD
|
|
|
o CONFIG_WANXL through CONFIG_WANXL_BUILD_FIRMWARE
|
|
|
o CONFIG_SCSI_AIC79XX through CONFIG_AIC79XX_BUILD_FIRMWARE
|
|
|
|
|
|
-menu "Firmware loader"
|
|
|
-
|
|
|
-config FW_LOADER
|
|
|
- tristate "Firmware loading facility" if EXPERT
|
|
|
- default y
|
|
|
- help
|
|
|
- This enables the firmware loading facility in the kernel. The kernel
|
|
|
- will first look for built-in firmware, if it has any. Next, it will
|
|
|
- look for the requested firmware in a series of filesystem paths:
|
|
|
-
|
|
|
- o firmware_class path module parameter or kernel boot param
|
|
|
- o /lib/firmware/updates/UTS_RELEASE
|
|
|
- o /lib/firmware/updates
|
|
|
- o /lib/firmware/UTS_RELEASE
|
|
|
- o /lib/firmware
|
|
|
-
|
|
|
- Enabling this feature only increases your kernel image by about
|
|
|
- 828 bytes, enable this option unless you are certain you don't
|
|
|
- need firmware.
|
|
|
-
|
|
|
- You typically want this built-in (=y) but you can also enable this
|
|
|
- as a module, in which case the firmware_class module will be built.
|
|
|
- You also want to be sure to enable this built-in if you are going to
|
|
|
- enable built-in firmware (CONFIG_EXTRA_FIRMWARE).
|
|
|
-
|
|
|
-if FW_LOADER
|
|
|
-
|
|
|
-config EXTRA_FIRMWARE
|
|
|
- string "Build named firmware blobs into the kernel binary"
|
|
|
- help
|
|
|
- Device drivers which require firmware can typically deal with
|
|
|
- having the kernel load firmware from the various supported
|
|
|
- /lib/firmware/ paths. This option enables you to build into the
|
|
|
- kernel firmware files. Built-in firmware searches are preceded
|
|
|
- over firmware lookups using your filesystem over the supported
|
|
|
- /lib/firmware paths documented on CONFIG_FW_LOADER.
|
|
|
-
|
|
|
- This may be useful for testing or if the firmware is required early on
|
|
|
- in boot and cannot rely on the firmware being placed in an initrd or
|
|
|
- initramfs.
|
|
|
-
|
|
|
- This option is a string and takes the (space-separated) names of the
|
|
|
- firmware files -- the same names that appear in MODULE_FIRMWARE()
|
|
|
- and request_firmware() in the source. These files should exist under
|
|
|
- the directory specified by the EXTRA_FIRMWARE_DIR option, which is
|
|
|
- /lib/firmware by default.
|
|
|
-
|
|
|
- For example, you might set CONFIG_EXTRA_FIRMWARE="usb8388.bin", copy
|
|
|
- the usb8388.bin file into /lib/firmware, and build the kernel. Then
|
|
|
- any request_firmware("usb8388.bin") will be satisfied internally
|
|
|
- inside the kernel without ever looking at your filesystem at runtime.
|
|
|
-
|
|
|
- WARNING: If you include additional firmware files into your binary
|
|
|
- kernel image that are not available under the terms of the GPL,
|
|
|
- then it may be a violation of the GPL to distribute the resulting
|
|
|
- image since it combines both GPL and non-GPL work. You should
|
|
|
- consult a lawyer of your own before distributing such an image.
|
|
|
-
|
|
|
-config EXTRA_FIRMWARE_DIR
|
|
|
- string "Firmware blobs root directory"
|
|
|
- depends on EXTRA_FIRMWARE != ""
|
|
|
- default "/lib/firmware"
|
|
|
- help
|
|
|
- This option controls the directory in which the kernel build system
|
|
|
- looks for the firmware files listed in the EXTRA_FIRMWARE option.
|
|
|
-
|
|
|
-config FW_LOADER_USER_HELPER
|
|
|
- bool "Enable the firmware sysfs fallback mechanism"
|
|
|
- help
|
|
|
- This option enables a sysfs loading facility to enable firmware
|
|
|
- loading to the kernel through userspace as a fallback mechanism
|
|
|
- if and only if the kernel's direct filesystem lookup for the
|
|
|
- firmware failed using the different /lib/firmware/ paths, or the
|
|
|
- path specified in the firmware_class path module parameter, or the
|
|
|
- firmware_class path kernel boot parameter if the firmware_class is
|
|
|
- built-in. For details on how to work with the sysfs fallback mechanism
|
|
|
- refer to Documentation/driver-api/firmware/fallback-mechanisms.rst.
|
|
|
-
|
|
|
- The direct filesystem lookup for firmware is always used first now.
|
|
|
-
|
|
|
- If the kernel's direct filesystem lookup for firmware fails to find
|
|
|
- the requested firmware a sysfs fallback loading facility is made
|
|
|
- available and userspace is informed about this through uevents.
|
|
|
- The uevent can be suppressed if the driver explicitly requested it,
|
|
|
- this is known as the driver using the custom fallback mechanism.
|
|
|
- If the custom fallback mechanism is used userspace must always
|
|
|
- acknowledge failure to find firmware as the timeout for the fallback
|
|
|
- mechanism is disabled, and failed requests will linger forever.
|
|
|
-
|
|
|
- This used to be the default firmware loading facility, and udev used
|
|
|
- to listen for uvents to load firmware for the kernel. The firmware
|
|
|
- loading facility functionality in udev has been removed, as such it
|
|
|
- can no longer be relied upon as a fallback mechanism. Linux no longer
|
|
|
- relies on or uses a fallback mechanism in userspace. If you need to
|
|
|
- rely on one refer to the permissively licensed firmwared:
|
|
|
-
|
|
|
- https://github.com/teg/firmwared
|
|
|
-
|
|
|
- Since this was the default firmware loading facility at one point,
|
|
|
- old userspace may exist which relies upon it, and as such this
|
|
|
- mechanism can never be removed from the kernel.
|
|
|
-
|
|
|
- You should only enable this functionality if you are certain you
|
|
|
- require a fallback mechanism and have a userspace mechanism ready to
|
|
|
- load firmware in case it is not found. One main reason for this may
|
|
|
- be if you have drivers which require firmware built-in and for
|
|
|
- whatever reason cannot place the required firmware in initramfs.
|
|
|
- Another reason kernels may have this feature enabled is to support a
|
|
|
- driver which explicitly relies on this fallback mechanism. Only two
|
|
|
- drivers need this today:
|
|
|
-
|
|
|
- o CONFIG_LEDS_LP55XX_COMMON
|
|
|
- o CONFIG_DELL_RBU
|
|
|
-
|
|
|
- Outside of supporting the above drivers, another reason for needing
|
|
|
- this may be that your firmware resides outside of the paths the kernel
|
|
|
- looks for and cannot possibly be specified using the firmware_class
|
|
|
- path module parameter or kernel firmware_class path boot parameter
|
|
|
- if firmware_class is built-in.
|
|
|
-
|
|
|
- A modern use case may be to temporarily mount a custom partition
|
|
|
- during provisioning which is only accessible to userspace, and then
|
|
|
- to use it to look for and fetch the required firmware. Such type of
|
|
|
- driver functionality may not even ever be desirable upstream by
|
|
|
- vendors, and as such is only required to be supported as an interface
|
|
|
- for provisioning. Since udev's firmware loading facility has been
|
|
|
- removed you can use firmwared or a fork of it to customize how you
|
|
|
- want to load firmware based on uevents issued.
|
|
|
-
|
|
|
- Enabling this option will increase your kernel image size by about
|
|
|
- 13436 bytes.
|
|
|
-
|
|
|
- If you are unsure about this, say N here, unless you are Linux
|
|
|
- distribution and need to support the above two drivers, or you are
|
|
|
- certain you need to support some really custom firmware loading
|
|
|
- facility in userspace.
|
|
|
-
|
|
|
-config FW_LOADER_USER_HELPER_FALLBACK
|
|
|
- bool "Force the firmware sysfs fallback mechanism when possible"
|
|
|
- depends on FW_LOADER_USER_HELPER
|
|
|
- help
|
|
|
- Enabling this option forces a sysfs userspace fallback mechanism
|
|
|
- to be used for all firmware requests which explicitly do not disable a
|
|
|
- a fallback mechanism. Firmware calls which do prohibit a fallback
|
|
|
- mechanism is request_firmware_direct(). This option is kept for
|
|
|
- backward compatibility purposes given this precise mechanism can also
|
|
|
- be enabled by setting the proc sysctl value to true:
|
|
|
-
|
|
|
- /proc/sys/kernel/firmware_config/force_sysfs_fallback
|
|
|
-
|
|
|
- If you are unsure about this, say N here.
|
|
|
-
|
|
|
-endif # FW_LOADER
|
|
|
-endmenu
|
|
|
+source "drivers/base/firmware_loader/Kconfig"
|
|
|
|
|
|
config WANT_DEV_COREDUMP
|
|
|
bool
|
Luis R. Rodriguez