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authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-15 22:58:58 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-15 22:58:58 +0300
commit486088bc4689f826b80aa317b45ac9e42e8b25ee (patch)
treeadf5847a6119d24da990d9e336f005c4a316e6be /Documentation/efi-stub.txt
parent52f6c588c77b76d548201470c2a28263a41b462b (diff)
parent43e5f7e1fa66531777c49791014c3124ea9208d8 (diff)
downloadlinux-486088bc4689f826b80aa317b45ac9e42e8b25ee.tar.xz
Merge tag 'standardize-docs' of git://git.lwn.net/linux
Pull documentation format standardization from Jonathan Corbet: "This series converts a number of top-level documents to the RST format without incorporating them into the Sphinx tree. The hope is to bring some uniformity to kernel documentation and, perhaps more importantly, have our existing docs serve as an example of the desired formatting for those that will be added later. Mauro has gone through and fixed up a lot of top-level documentation files to make them conform to the RST format, but without moving or renaming them in any way. This will help when we incorporate the ones we want to keep into the Sphinx doctree, but the real purpose is to bring a bit of uniformity to our documentation and let the top-level docs serve as examples for those writing new ones" * tag 'standardize-docs' of git://git.lwn.net/linux: (84 commits) docs: kprobes.txt: Fix whitespacing tee.txt: standardize document format cgroup-v2.txt: standardize document format dell_rbu.txt: standardize document format zorro.txt: standardize document format xz.txt: standardize document format xillybus.txt: standardize document format vfio.txt: standardize document format vfio-mediated-device.txt: standardize document format unaligned-memory-access.txt: standardize document format this_cpu_ops.txt: standardize document format svga.txt: standardize document format static-keys.txt: standardize document format smsc_ece1099.txt: standardize document format SM501.txt: standardize document format siphash.txt: standardize document format sgi-ioc4.txt: standardize document format SAK.txt: standardize document format rpmsg.txt: standardize document format robust-futexes.txt: standardize document format ...
Diffstat (limited to 'Documentation/efi-stub.txt')
-rw-r--r--Documentation/efi-stub.txt25
1 files changed, 15 insertions, 10 deletions
diff --git a/Documentation/efi-stub.txt b/Documentation/efi-stub.txt
index e15746988261..41df801f9a50 100644
--- a/Documentation/efi-stub.txt
+++ b/Documentation/efi-stub.txt
@@ -1,5 +1,6 @@
- The EFI Boot Stub
- ---------------------------
+=================
+The EFI Boot Stub
+=================
On the x86 and ARM platforms, a kernel zImage/bzImage can masquerade
as a PE/COFF image, thereby convincing EFI firmware loaders to load
@@ -25,7 +26,8 @@ a certain sense it *IS* the boot loader.
The EFI boot stub is enabled with the CONFIG_EFI_STUB kernel option.
-**** How to install bzImage.efi
+How to install bzImage.efi
+--------------------------
The bzImage located in arch/x86/boot/bzImage must be copied to the EFI
System Partition (ESP) and renamed with the extension ".efi". Without
@@ -37,14 +39,16 @@ may not need to be renamed. Similarly for arm64, arch/arm64/boot/Image
should be copied but not necessarily renamed.
-**** Passing kernel parameters from the EFI shell
+Passing kernel parameters from the EFI shell
+--------------------------------------------
-Arguments to the kernel can be passed after bzImage.efi, e.g.
+Arguments to the kernel can be passed after bzImage.efi, e.g.::
fs0:> bzImage.efi console=ttyS0 root=/dev/sda4
-**** The "initrd=" option
+The "initrd=" option
+--------------------
Like most boot loaders, the EFI stub allows the user to specify
multiple initrd files using the "initrd=" option. This is the only EFI
@@ -54,9 +58,9 @@ kernel when it boots.
The path to the initrd file must be an absolute path from the
beginning of the ESP, relative path names do not work. Also, the path
is an EFI-style path and directory elements must be separated with
-backslashes (\). For example, given the following directory layout,
+backslashes (\). For example, given the following directory layout::
-fs0:>
+ fs0:>
Kernels\
bzImage.efi
initrd-large.img
@@ -66,7 +70,7 @@ fs0:>
initrd-medium.img
to boot with the initrd-large.img file if the current working
-directory is fs0:\Kernels, the following command must be used,
+directory is fs0:\Kernels, the following command must be used::
fs0:\Kernels> bzImage.efi initrd=\Kernels\initrd-large.img
@@ -76,7 +80,8 @@ which understands relative paths, whereas the rest of the command line
is passed to bzImage.efi.
-**** The "dtb=" option
+The "dtb=" option
+-----------------
For the ARM and arm64 architectures, we also need to be able to provide a
device tree to the kernel. This is done with the "dtb=" command line option,