Re: [PATCH v5 2/3] clocksource: update "fn" at CLOCKSOURCE_OF_DECLARE() of nps400 timer

From: Daniel Lezcano
Date: Mon Nov 14 2016 - 03:52:20 EST


On Sun, Nov 13, 2016 at 09:24:31AM +0200, Noam Camus wrote:
> From: Noam Camus <noamca@xxxxxxxxxxxx>
>
> nps_setup_clocksource() should take node as only argument i.e.:
> replace
> int __init nps_setup_clocksource(struct device_node *node, struct clk *clk)
> with
> int __init nps_setup_clocksource(struct device_node *node)

because ...

> This is also serve as preperation for next patch which adds support

s/This is also/This also/
s/preperation/preparation/


> for clockevents to nps400.
> Specifically we add new function nps_get_timer_clk() to serve clocksource
> and later clockevent registration.
>
> Signed-off-by: Noam Camus <noamca@xxxxxxxxxxxx>
> ---
> drivers/clocksource/timer-nps.c | 63 +++++++++++++++++++++++----------------
> 1 files changed, 37 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/clocksource/timer-nps.c b/drivers/clocksource/timer-nps.c
> index 70c149a..eeef9e9 100644
> --- a/drivers/clocksource/timer-nps.c
> +++ b/drivers/clocksource/timer-nps.c
> @@ -46,7 +46,33 @@
> /* This array is per cluster of CPUs (Each NPS400 cluster got 256 CPUs) */
> static void *nps_msu_reg_low_addr[NPS_CLUSTER_NUM] __read_mostly;
>
> -static unsigned long nps_timer_rate;
> +static int __init nps_get_timer_clk(struct device_node *node,
> + unsigned long *timer_freq,
> + struct clk **clk)
> +{
> + int ret;
> +
> + *clk = of_clk_get(node, 0);
> + if (IS_ERR(*clk)) {
> + pr_err("timer missing clk");
> + return PTR_ERR(*clk);
> + }
> +
> + ret = clk_prepare_enable(*clk);
> + if (ret) {
> + pr_err("Couldn't enable parent clk\n");
> + return ret;
> + }
> +
> + *timer_freq = clk_get_rate(*clk);
> + if (!(*timer_freq)) {
> + pr_err("Couldn't get clk rate\n");
> + clk_disable_unprepare(*clk);
> + return 1;

s/return 1/return -EINVAL/

What about clk_put() ?

> + }
> +
> + return 0;
> +}
>
> static cycle_t nps_clksrc_read(struct clocksource *clksrc)
> {
> @@ -55,26 +81,24 @@ static cycle_t nps_clksrc_read(struct clocksource *clksrc)
> return (cycle_t)ioread32be(nps_msu_reg_low_addr[cluster]);
> }
>
> -static int __init nps_setup_clocksource(struct device_node *node,
> - struct clk *clk)
> +static int __init nps_setup_clocksource(struct device_node *node)
> {
> int ret, cluster;
> + struct clk *clk;
> + unsigned long nps_timer1_freq;
> +
>
> for (cluster = 0; cluster < NPS_CLUSTER_NUM; cluster++)
> nps_msu_reg_low_addr[cluster] =
> nps_host_reg((cluster << NPS_CLUSTER_OFFSET),
> - NPS_MSU_BLKID, NPS_MSU_TICK_LOW);
> + NPS_MSU_BLKID, NPS_MSU_TICK_LOW);
>
> - ret = clk_prepare_enable(clk);
> - if (ret) {
> - pr_err("Couldn't enable parent clock\n");
> + ret = nps_get_timer_clk(node, &nps_timer1_freq, &clk);
> + if (ret)
> return ret;
> - }
>
> - nps_timer_rate = clk_get_rate(clk);
> -
> - ret = clocksource_mmio_init(nps_msu_reg_low_addr, "EZnps-tick",
> - nps_timer_rate, 301, 32, nps_clksrc_read);
> + ret = clocksource_mmio_init(nps_msu_reg_low_addr, "nps-tick",
> + nps_timer1_freq, 300, 32, nps_clksrc_read);
> if (ret) {
> pr_err("Couldn't register clock source.\n");
> clk_disable_unprepare(clk);
> @@ -83,18 +107,5 @@ static int __init nps_setup_clocksource(struct device_node *node,
> return ret;
> }
>
> -static int __init nps_timer_init(struct device_node *node)
> -{
> - struct clk *clk;
> -
> - clk = of_clk_get(node, 0);
> - if (IS_ERR(clk)) {
> - pr_err("Can't get timer clock.\n");
> - return PTR_ERR(clk);
> - }
> -
> - return nps_setup_clocksource(node, clk);
> -}
> -
> CLOCKSOURCE_OF_DECLARE(ezchip_nps400_clksrc, "ezchip,nps400-timer",
> - nps_timer_init);
> + nps_setup_clocksource);
> --
> 1.7.1
>

--

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