[RFC][PATCH 2/2] ARM: ioremap: Add IO mapping space reused support.

Richard Lee superlibj8301 at gmail.com
Mon May 12 18:45:08 PDT 2014

> On Mon, May 12, 2014 at 3:51 PM, Arnd Bergmann <arnd at arndb.de> wrote:
> On Monday 12 May 2014 10:19:55 Richard Lee wrote:
>> For the IO mapping, for the same physical address space maybe
>> mapped more than one time, for example, in some SoCs:
>> 0x20000000 ~ 0x20001000: are global control IO physical map,
>> and this range space will be used by many drivers.
>> And then if each driver will do the same ioremap operation, we
>> will waste to much malloc virtual spaces.
>> This patch add IO mapping space reused support.
>> Signed-off-by: Richard Lee <superlibj at gmail.com>
> What happens if the first driver then unmaps the area?

If the first driver will unmap the area, it shouldn't do any thing
except decreasing the 'used' counter.


Richard Lee

>         Arnd

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