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authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-07 10:37:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-07 10:37:54 -0700
commitdd6ec12f3bf83ca3c4e712a9f35960aec779f6f9 (patch)
tree8b6f9f187eb0ae621a64798270c420143c698484 /Documentation/ABI
parent21c19bc7ee256094aba74af8d91a824da4bc36af (diff)
parenta4485b545e2fad4d65732cb7c60089bf4246de5c (diff)
downloadlinux-dd6ec12f3bf83ca3c4e712a9f35960aec779f6f9.tar.bz2
Merge tag 'devicetree-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull DeviceTree updates from Rob Herring: - vsprintf format specifier %pOF for device_node's. This will enable us to stop storing the full node names. Conversion of users will happen next cycle. - Update documentation to point to DT specification instead of ePAPR. - Split out graph and property functions to a separate file. - New of-graph functions for ALSA - Add vendor prefixes for RISC-V, Linksys, iWave Systems, Roofull, Itead, and BananaPi. - Improve dtx_diff utility filename printing. * tag 'devicetree-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (32 commits) of: document /sys/firmware/fdt dt-bindings: Add RISC-V vendor prefix vsprintf: Add %p extension "%pOF" for device tree of: find_node_by_full_name rewrite to compare each level of: use kbasename instead of open coding dt-bindings: thermal: add file extension to brcm,ns-thermal of: update ePAPR references to point to Devicetree Specification scripts/dtc: dtx_diff - Show real file names in diff header of: detect invalid phandle in overlay of: be consistent in form of file mode of: make __of_attach_node() static of: address.c header comment typo of: fdt.c header comment typo of: make of_fdt_is_compatible() static dt-bindings: display-timing.txt convert non-ascii characters to ascii Documentation: remove overlay-notes reference to non-existent file dt-bindings: usb: exynos-usb: Add missing required VDD properties dt-bindings: Add vendor prefix for Linksys MAINTAINERS: add device tree ABI documentation file of: Add vendor prefix for iWave Systems Technologies Pvt. Ltd ...
Diffstat (limited to 'Documentation/ABI')
-rw-r--r--Documentation/ABI/testing/sysfs-firmware-ofw26
1 files changed, 25 insertions, 1 deletions
diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
index f562b188e71d..edcab3ccfcc0 100644
--- a/Documentation/ABI/testing/sysfs-firmware-ofw
+++ b/Documentation/ABI/testing/sysfs-firmware-ofw
@@ -1,6 +1,6 @@
What: /sys/firmware/devicetree/*
Date: November 2013
-Contact: Grant Likely <grant.likely@linaro.org>
+Contact: Grant Likely <grant.likely@arm.com>, devicetree@vger.kernel.org
Description:
When using OpenFirmware or a Flattened Device Tree to enumerate
hardware, the device tree structure will be exposed in this
@@ -26,3 +26,27 @@ Description:
name plus address). Properties are represented as files
in the directory. The contents of each file is the exact
binary data from the device tree.
+
+What: /sys/firmware/fdt
+Date: February 2015
+KernelVersion: 3.19
+Contact: Frank Rowand <frowand.list@gmail.com>, devicetree@vger.kernel.org
+Description:
+ Exports the FDT blob that was passed to the kernel by
+ the bootloader. This allows userland applications such
+ as kexec to access the raw binary. This blob is also
+ useful when debugging since it contains any changes
+ made to the blob by the bootloader.
+
+ The fact that this node does not reside under
+ /sys/firmware/device-tree is deliberate: FDT is also used
+ on arm64 UEFI/ACPI systems to communicate just the UEFI
+ and ACPI entry points, but the FDT is never unflattened
+ and used to configure the system.
+
+ A CRC32 checksum is calculated over the entire FDT
+ blob, and verified at late_initcall time. The sysfs
+ entry is instantiated only if the checksum is valid,
+ i.e., if the FDT blob has not been modified in the mean
+ time. Otherwise, a warning is printed.
+Users: kexec, debugging