[PATCH 2/5] Documentation: Update documentation for UIO_MEM_PHYS_CACHE

Ankit Jindal ankit.jindal at linaro.org
Wed Sep 17 17:03:02 PDT 2014


On 15 September 2014 01:31, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Tue, Sep 09, 2014 at 03:26:56PM +0530, Ankit Jindal wrote:
>> This patch update UIO documentation for new mem region
>> type UIO_MEM_PHYS_CACHE.
>>
>> Signed-off-by: Ankit Jindal <ankit.jindal at linaro.org>
>> Signed-off-by: Tushar Jagad <tushar.jagad at linaro.org>
>> ---
>>  Documentation/DocBook/uio-howto.tmpl |    3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl
>> index bbe9c1f..49e47d4 100644
>> --- a/Documentation/DocBook/uio-howto.tmpl
>> +++ b/Documentation/DocBook/uio-howto.tmpl
>> @@ -530,7 +530,8 @@ the memory region, it will show up in the corresponding sysfs node.
>>  <varname>UIO_MEM_PHYS</varname> if you you have physical memory on your
>>  card to be mapped. Use <varname>UIO_MEM_LOGICAL</varname> for logical
>>  memory (e.g. allocated with <function>kmalloc()</function>). There's also
>> -<varname>UIO_MEM_VIRTUAL</varname> for virtual memory.
>> +<varname>UIO_MEM_VIRTUAL</varname> for virtual memory and
>> +<varname>UIO_MEM_PHYS_CACHE</varname> for physical cacheable memory.
>
> When I read this, I wondered what "physical cacheable memory" was.
> Then I found that what you're doing with this is mapping physical
> memory into userspace with cacheable attributes.
>
> So, to avoid confusion, this should be "for physical memory, which
> will be cacheably mapped" or similar.

Thanks, will frame better in next version.

Thanks,
Ankit



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