diff options
| author | Frank Rowand <frank.rowand@sony.com> | 2017-06-28 15:21:46 -0700 |
|---|---|---|
| committer | Rob Herring <robh@kernel.org> | 2017-06-30 09:16:51 -0500 |
| commit | 5e1743c0af9d5179cf575c0bc2777af02a79b911 (patch) | |
| tree | 835eb7527312bdb7ac5710b938f65535e0ea8060 /Documentation/ABI | |
| parent | ce437750e895639332cdde4a65d054bca526218e (diff) | |
of: document /sys/firmware/fdt
Add ABI documentation for /sys/firmware/fdt
Update contact email for /sys/firmware/devicetree/* and add mail list
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Acked-by: Grant Likely <grant.likely@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-firmware-ofw | 26 |
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 |