[PATCH v2 02/16] arm64: dts: add sp804 timer node for Hi6220

On Mon, Apr 4, 2016 at 3:43 AM, Leo Yan [off-list ref] wrote:

On Sun, Apr 03, 2016 at 09:23:42PM +0200, Linus Walleij wrote:

quoted

On Sat, Apr 2, 2016 at 11:29 AM, Guodong Xu [off-list ref] wrote:

quoted

By chance the code in the driver will allow just one clock and
will then assume that both the bus to the timer and the timer
itself is clocked from the same clock. But I highly doubt that this
is the case.

This patch has been sent out for review previously [1]; So I refered
other platforms and changed to only enable apb bus clock due I have
not found timer enabling bits in Hi6220's spec.

This is not about enabling/disabling the clock(s) to the timer.
It doesn't matter if these clocks are always on.

It is about determining the *frequency* of the timers.

It is vital that the timer driver get the right frequency of the clock
to the block from the clock implementation, and I do not think
it is the same as the "apb_pclk".

The thing is that of course "any frequency" will
work but what you will notice is that the timer runs very
weirdly compared to wall-clock time unless the right clock
yielding the right frequency has been specified here.

Yours,
Linus Walleij