[PATCH v2 05/14] ARM: integrator: use clocksource_of_init for sp804

Russell King - ARM Linux linux at arm.linux.org.uk
Fri Mar 15 07:54:22 EDT 2013


On Tue, Mar 12, 2013 at 02:15:09PM -0500, Rob Herring wrote:
> You are breaking existing dtb's changing this, but this is wrong for
> other reasons. The integrator does not have an SP804. It is the same
> programming model,

No, it is not the same programming model.  It is a subset of the model.
Integrator/AP is only 16-bit, and needs to have a prescaler configured
according to the clockrate.  Integrator/CP and later platforms have
SP804, which looks the same, but is 32-bit instead.

If you look at arch/arm/include/asm/hardware/arm_timer.h, you will see
that I fully documented what registers and bits are present on each
platform of AP, CP, Versatile/AB,PB and Realview.

Note that even through the CP and Versatile platforms are both called
SP804, there are subtle differences between the implementations.



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