diff options
author | Jonathan Corbet <corbet@lwn.net> | 2023-03-15 02:06:44 +0300 |
---|---|---|
committer | Jonathan Corbet <corbet@lwn.net> | 2023-03-30 21:58:51 +0300 |
commit | ff61f0791ce969d2db6c9f3b71d74ceec0a2e958 (patch) | |
tree | fe32be44aaf65f9c436a8f37cd4a18f6ec47c3cb /Documentation/arch/x86/booting-dt.rst | |
parent | f030c8fd64cea916d57d40bb7b59c1cff9ea3bc3 (diff) | |
download | linux-ff61f0791ce969d2db6c9f3b71d74ceec0a2e958.tar.xz |
docs: move x86 documentation into Documentation/arch/
Move the x86 documentation under Documentation/arch/ as a way of cleaning
up the top-level directory and making the structure of our docs more
closely match the structure of the source directories it describes.
All in-kernel references to the old paths have been updated.
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-arch@vger.kernel.org
Cc: x86@kernel.org
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20230315211523.108836-1-corbet@lwn.net/
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation/arch/x86/booting-dt.rst')
-rw-r--r-- | Documentation/arch/x86/booting-dt.rst | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/Documentation/arch/x86/booting-dt.rst b/Documentation/arch/x86/booting-dt.rst new file mode 100644 index 000000000000..b089ffd56e6e --- /dev/null +++ b/Documentation/arch/x86/booting-dt.rst @@ -0,0 +1,21 @@ +.. SPDX-License-Identifier: GPL-2.0 + +DeviceTree Booting +------------------ + + There is one single 32bit entry point to the kernel at code32_start, + the decompressor (the real mode entry point goes to the same 32bit + entry point once it switched into protected mode). That entry point + supports one calling convention which is documented in + Documentation/arch/x86/boot.rst + The physical pointer to the device-tree block is passed via setup_data + which requires at least boot protocol 2.09. + The type filed is defined as + + #define SETUP_DTB 2 + + This device-tree is used as an extension to the "boot page". As such it + does not parse / consider data which is already covered by the boot + page. This includes memory size, reserved ranges, command line arguments + or initrd address. It simply holds information which can not be retrieved + otherwise like interrupt routing or a list of devices behind an I2C bus. |