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authorDave Airlie <airlied@redhat.com>2015-04-20 01:32:26 (GMT)
committerDave Airlie <airlied@redhat.com>2015-04-20 03:05:20 (GMT)
commit2c33ce009ca2389dbf0535d0672214d09738e35e (patch)
tree6186a6458c3c160385d794a23eaf07c786a9e61b /Documentation/devicetree/booting-without-of.txt
parentcec32a47010647e8b0603726ebb75b990a4057a4 (diff)
parent09d51602cf84a1264946711dd4ea0dddbac599a1 (diff)
downloadlinux-2c33ce009ca2389dbf0535d0672214d09738e35e.tar.xz
Merge Linus master into drm-next
The merge is clean, but the arm build fails afterwards, due to API changes in the regulator tree. I've included the patch into the merge to fix the build. Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'Documentation/devicetree/booting-without-of.txt')
-rw-r--r--Documentation/devicetree/booting-without-of.txt28
1 files changed, 28 insertions, 0 deletions
diff --git a/Documentation/devicetree/booting-without-of.txt b/Documentation/devicetree/booting-without-of.txt
index 7768518..e49e423 100644
--- a/Documentation/devicetree/booting-without-of.txt
+++ b/Documentation/devicetree/booting-without-of.txt
@@ -15,6 +15,7 @@ Table of Contents
1) Entry point for arch/arm
2) Entry point for arch/powerpc
3) Entry point for arch/x86
+ 4) Entry point for arch/mips/bmips
II - The DT block format
1) Header
@@ -288,6 +289,33 @@ it with special cases.
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.
+4) Entry point for arch/mips/bmips
+----------------------------------
+
+ Some bootloaders only support a single entry point, at the start of the
+ kernel image. Other bootloaders will jump to the ELF start address.
+ Both schemes are supported; CONFIG_BOOT_RAW=y and CONFIG_NO_EXCEPT_FILL=y,
+ so the first instruction immediately jumps to kernel_entry().
+
+ Similar to the arch/arm case (b), a DT-aware bootloader is expected to
+ set up the following registers:
+
+ a0 : 0
+
+ a1 : 0xffffffff
+
+ a2 : Physical pointer to the device tree block (defined in chapter
+ II) in RAM. The device tree can be located anywhere in the first
+ 512MB of the physical address space (0x00000000 - 0x1fffffff),
+ aligned on a 64 bit boundary.
+
+ Legacy bootloaders do not use this convention, and they do not pass in a
+ DT block. In this case, Linux will look for a builtin DTB, selected via
+ CONFIG_DT_*.
+
+ This convention is defined for 32-bit systems only, as there are not
+ currently any 64-bit BMIPS implementations.
+
II - The DT block format
========================