From 7211da17785536bacd3171a28bc6a3853c8bb477 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Mon, 14 Feb 2011 08:13:20 -0700 Subject: Revert "dt: add documentation of ARM dt boot interface" This reverts commit 9830fcd6f6a4781d8b46d2b35c13b39f30915c63. The ARM dt support has not been merged yet; this documentation update was premature. Signed-off-by: Grant Likely --- Documentation/devicetree/booting-without-of.txt | 40 ------------------------- 1 file changed, 40 deletions(-) (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/booting-without-of.txt b/Documentation/devicetree/booting-without-of.txt index 9381a1481027..28b1c9d3d351 100644 --- a/Documentation/devicetree/booting-without-of.txt +++ b/Documentation/devicetree/booting-without-of.txt @@ -13,7 +13,6 @@ Table of Contents I - Introduction 1) Entry point for arch/powerpc - 2) Entry point for arch/arm II - The DT block format 1) Header @@ -226,45 +225,6 @@ it with special cases. cannot support both configurations with Book E and configurations with classic Powerpc architectures. -2) Entry point for arch/arm ---------------------------- - - There is one single entry point to the kernel, at the start - of the kernel image. That entry point supports two calling - conventions. A summary of the interface is described here. A full - description of the boot requirements is documented in - Documentation/arm/Booting - - a) ATAGS interface. Minimal information is passed from firmware - to the kernel with a tagged list of predefined parameters. - - r0 : 0 - - r1 : Machine type number - - r2 : Physical address of tagged list in system RAM - - b) Entry with a flattened device-tree block. Firmware loads the - physical address of the flattened device tree block (dtb) into r2, - r1 is not used, but it is considered good practise to use a valid - machine number as described in Documentation/arm/Booting. - - r0 : 0 - - r1 : Valid machine type number. When using a device tree, - a single machine type number will often be assigned to - represent a class or family of SoCs. - - r2 : physical pointer to the device-tree block - (defined in chapter II) in RAM. Device tree can be located - anywhere in system RAM, but it should be aligned on a 32 bit - boundary. - - The kernel will differentiate between ATAGS and device tree booting by - reading the memory pointed to by r1 and looking for either the flattened - device tree block magic value (0xd00dfeed) or the ATAG_CORE value at - offset 0x4 from r2 (0x54410001). - II - The DT block format ======================== -- cgit v1.2.2