linux-kernel - Re: [PATCH v5 8/8] dt: add documentation of ARM dt boot interface

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <alpine.LFD.2.00.1104292034450.24613@xanadu.home>
Date:	Fri, 29 Apr 2011 20:37:24 -0400 (EDT)
From:	Nicolas Pitre <nicolas.pitre@...aro.org>
To:	Grant Likely <grant.likely@...retlab.ca>
cc:	devicetree-discuss@...ts.ozlabs.org,
	linux-arm-kernel@...ts.infradead.org,
	Russell King <linux@....linux.org.uk>,
	lkml <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v5 8/8] dt: add documentation of ARM dt boot interface

On Fri, 29 Apr 2011, Grant Likely wrote:

> diff --git a/Documentation/devicetree/booting-without-of.txt b/Documentation/devicetree/booting-without-of.txt
> index 50619a0..31d7e8a 100644
> --- a/Documentation/devicetree/booting-without-of.txt
> +++ b/Documentation/devicetree/booting-without-of.txt
[...]
> +1) 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 64 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

s/r1/r2/


Nicolas
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/