[PATCH v10 2/7] ARM: hi3xxx: add board support with device tree

Arnd Bergmann arnd at arndb.de
Tue Oct 15 14:06:38 EDT 2013


On Tuesday 15 October 2013, Haojian Zhuang wrote:
> On 15 October 2013 21:00, Arnd Bergmann <arnd at arndb.de> wrote:
> > On Tuesday 15 October 2013, Haojian Zhuang wrote:
> >>
> >> Add board support with device tree for Hisilicon Hi3620 SoC platform.
> >>
> >> Changelog:
> >> v10:
> >> 1. Add .map_io() & debug_ll_io_init() back. Since debug_ll_io_init() is
> >> only called if .map_io() isn't assigned. Use .map_io() to setup static
> >> IO mapping that is used in clock driver.
> >>
> >
> > This seems like a step in the wrong direction. Why would you want to use
> > a static I/O mapping in the clock driver?
> >
> 
> Because Stephen & Kevin asked me to use unit address in DTS file. They
> also require me to use reg property to present real hardware address
> in DTS file.

Ah, so it's just an optimization, not required to make the clock driver
work, I misread that. Can you add a comment near the hi3620_io_desc
definition and verify that it still works without it?

I would also recommend to extend that static mapping to the entire
0xfc800000-0xfcbfffff range, or whatever you can use to get the most
I/O devices with a small number of TLB entries.

	Arnd



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