Hi Neil,

On 22/03/16 09:21, Neil Armstrong wrote:

On 03/17/2016 08:21 PM, Robin Murphy wrote:

quoted

On 17/03/16 19:00, Rob Herring wrote:

quoted

On Thu, Mar 17, 2016 at 1:06 PM, Robin Murphy [off-list ref] wrote:

quoted

Hi Rob,

On 17/03/16 17:09, Rob Herring wrote:

quoted

That would not be an SP804 nor would the vendor be ARM in that case. So
add a new compatible string for the vendor that decided to hack up ARM's
IP block.

By all accounts this is some ancient reference design[1] which later evolved
_into_ the SP804, so that vendor would probably still be ARM ;)

Right.

quoted

A separate compatible string would indeed make more sense, though. Both
semantically and in terms of letting the driver account for the differences
automatically.

Robin.

[1]:http://infocenter.arm.com/help/topic/com.arm.doc.ddi0170a/I350250.html

Humm, same as integrator timers perhaps?

Having had a quick look, what the Integrator/AP manual describes certainly smells like the same basic block as the "AMBA Timer" - 16 bit counters and the same control register layout - albeit in a mutant triple-timer version with a bigger offset between each register set. Integrator/CP, on the other hand, looks much more SP804-like.

Robin.

Hi,

I will switch to oxsemi,ox810se-rps-timer since it need a specific register width that will be handled by the driver.

By "needs a specific register width" do you mean the OxSemi 
implementation will give a bus error on a 32-bit access and requires 
16-bit accessors? If so, I'd expect to see patch 1 changing readl()s to 
readw()s at least somewhere. Otherwise, if it's merely that the 
clocksource API needs to know the upper 16 bits of a word it reads are 
undefined, then since that's the standard behaviour I'd be inclined to 
add it to the driver as a canonical "arm,amba-timer" implementation, 
then have your implementation-specific compatible on top of that just in 
case.

Robin.

Thanks,
Neil

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