[PATCH 8/8] clocksource: xilinx_ttc: add OF_CLK support

Josh Cartwright josh.cartwright at ni.com
Thu Nov 1 22:56:47 EDT 2012


On Wed, Oct 31, 2012 at 01:56:14PM -0600, Josh Cartwright wrote:
> Add support for retrieving TTC configuration from device tree.  This
> includes the ability to pull information about the driving clocks from
> the of_clk bindings.
> 
> Signed-off-by: Josh Cartwright <josh.cartwright at ni.com>
> ---
> diff --git a/drivers/clocksource/xilinx_ttc.c b/drivers/clocksource/xilinx_ttc.c
> index ff38b3e..a4718f7 100644
> --- a/drivers/clocksource/xilinx_ttc.c
> +++ b/drivers/clocksource/xilinx_ttc.c
> @@ -209,7 +153,8 @@ static struct clocksource clocksource_xttcpss = {
>  static int xttcpss_set_next_event(unsigned long cycles,
>  					struct clock_event_device *evt)
>  {
> -	struct xttcpss_timer *timer = &timers[XTTCPSS_CLOCKEVENT];
> +	struct xttcpss_timer_clockevent *xttce = to_xttcpss_timer_clkevent(evt);
> +	struct xttcpss_timer *timer = &xttce->xttc;
>  
>  	xttcpss_set_interval(timer, cycles);
>  	return 0;
> @@ -224,12 +169,14 @@ static int xttcpss_set_next_event(unsigned long cycles,
>  static void xttcpss_set_mode(enum clock_event_mode mode,
>  					struct clock_event_device *evt)
>  {
> -	struct xttcpss_timer *timer = &timers[XTTCPSS_CLOCKEVENT];
> +	struct xttcpss_timer_clockevent *xttce = to_xttcpss_timer_clkevent(evt);
> +	struct xttcpss_timer *timer = &xttce->xttc;
>  	u32 ctrl_reg;
>  
>  	switch (mode) {
>  	case CLOCK_EVT_MODE_PERIODIC:
> -		xttcpss_set_interval(timer, TIMER_RATE / HZ);
> +		xttcpss_set_interval(timer,
> +				     clk_get_rate(xttce->clk) / PRESCALE);

I discovered with further testing that the above calculation is broken;
calculated interval also needs to be divided by HZ.

(I'll post a v2; just wanted to get this out there in the slim chance
anyone's testing this ;)

  Josh



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