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SubjectRe: [PATCH 1/2] Documentation: arm: early_ioremap
On 06/25/2013 12:46:40 PM, Leif Lindholm wrote:
> This patch provides documentation of the early_ioremap()
> functionality,
> including its implementation and usage instructions.
>
> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
> ---
> Documentation/arm/00-INDEX | 2 ++
> Documentation/arm/early_ioremap.txt | 12 ++++++++++++
> 2 files changed, 14 insertions(+)
> create mode 100644 Documentation/arm/early_ioremap.txt
>
> diff --git a/Documentation/arm/00-INDEX b/Documentation/arm/00-INDEX
> index 36420e1..4978456 100644
> --- a/Documentation/arm/00-INDEX
> +++ b/Documentation/arm/00-INDEX
> @@ -24,6 +24,8 @@ SPEAr
> - ST SPEAr platform Linux Overview
> VFP/
> - Release notes for Linux Kernel Vector Floating Point support
> code
> +early_ioremap.txt
> + - documentation of the early_ioremap() functionality
> empeg/
> - Ltd's Empeg MP3 Car Audio Player
> mem_alignment
> diff --git a/Documentation/arm/early_ioremap.txt
> b/Documentation/arm/early_ioremap.txt
> new file mode 100644
> index 0000000..178f791
> --- /dev/null
> +++ b/Documentation/arm/early_ioremap.txt
> @@ -0,0 +1,12 @@
> +early_ioremap() and early_iounmap() rovide a mechanism for
> temporarily mapping

Typo: provide

> +in small blocks of memory, identified by their physical address,
> into the
> +fixmap virtual address block before paging_init() has been called
> and more
> +flexible mapping functions are available.
> +
> +Due to its direct method, it also gets around potential need for
> special
> +handling of regions that end up in highmem.
> +
> +It supports up to 7 simultaneously mapped regions of up to 128KB
> each.
> +All regions are mapped as non-shareable device memory.
> +
> +Specify 'early_ioremap_debug' on the kernel commandline for verbose
> output.
> --
> 1.7.10.4

Minor quibble: this explains what it does, but nothing about how to use
it. Do these mappings persist if you don't unmap them, or does
paging_init() clear them?

Oh well:

Acked-by: Rob Landley <rob@landley.net>

Rob

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