2020-10-17 16:20:39

by Fabien Parent

Subject: [PATCH 2/2] clocksource: mediatek: add clk13m and bus clock support

Some MediaTek SoC like MT8516 need to enable additional clocks
for the GPT timer. Enable them if present.

Signed-off-by: Fabien Parent <[email protected]>
---
drivers/clocksource/timer-mediatek.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/clocksource/timer-mediatek.c b/drivers/clocksource/timer-mediatek.c
index 9318edcd8963..42e2d2090484 100644
--- a/drivers/clocksource/timer-mediatek.c
+++ b/drivers/clocksource/timer-mediatek.c
@@ -9,6 +9,7 @@

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

+#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/interrupt.h>
@@ -278,8 +279,19 @@ static int __init mtk_syst_init(struct device_node *node)

static int __init mtk_gpt_init(struct device_node *node)
{
+ struct clk *clk_13m, *clk_bus;
int ret;

+ /* Optional clock*/
+ clk_13m = of_clk_get_by_name(node, "clk13m");
+ if (!IS_ERR(clk_13m))
+ clk_prepare_enable(clk_13m);
+
+ /* Optional clock*/
+ clk_bus = of_clk_get_by_name(node, "bus");
+ if (!IS_ERR(clk_bus))
+ clk_prepare_enable(clk_bus);
+
to.clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
to.clkevt.set_state_shutdown = mtk_gpt_clkevt_shutdown;
to.clkevt.set_state_periodic = mtk_gpt_clkevt_set_periodic;
--
2.28.0

2020-10-26 17:32:51

by Rob Herring (Arm)

Subject: Re: [PATCH 2/2] clocksource: mediatek: add clk13m and bus clock support

On Sat, Oct 17, 2020 at 05:38:57PM +0200, Fabien Parent wrote:
> Some MediaTek SoC like MT8516 need to enable additional clocks
> for the GPT timer. Enable them if present.
>
> Signed-off-by: Fabien Parent <[email protected]>
> ---
> drivers/clocksource/timer-mediatek.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/clocksource/timer-mediatek.c b/drivers/clocksource/timer-mediatek.c
> index 9318edcd8963..42e2d2090484 100644
> --- a/drivers/clocksource/timer-mediatek.c
> +++ b/drivers/clocksource/timer-mediatek.c
> @@ -9,6 +9,7 @@
>
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>
> +#include <linux/clk.h>
> #include <linux/clockchips.h>
> #include <linux/clocksource.h>
> #include <linux/interrupt.h>
> @@ -278,8 +279,19 @@ static int __init mtk_syst_init(struct device_node *node)
>
> static int __init mtk_gpt_init(struct device_node *node)
> {
> + struct clk *clk_13m, *clk_bus;
> int ret;
>
> + /* Optional clock*/

Then use the optional api variant.

> + clk_13m = of_clk_get_by_name(node, "clk13m");
> + if (!IS_ERR(clk_13m))

And then you can drop this check (or handle it for any error other than
clock is not present).

> + clk_prepare_enable(clk_13m);
> +
> + /* Optional clock*/
> + clk_bus = of_clk_get_by_name(node, "bus");
> + if (!IS_ERR(clk_bus))
> + clk_prepare_enable(clk_bus);
> +
> to.clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
> to.clkevt.set_state_shutdown = mtk_gpt_clkevt_shutdown;
> to.clkevt.set_state_periodic = mtk_gpt_clkevt_set_periodic;
> --
> 2.28.0
>

2020-10-26 23:47:22

by Fabien Parent

Subject: Re: [PATCH 2/2] clocksource: mediatek: add clk13m and bus clock support

Hi Rob,

On Mon, Oct 26, 2020 at 2:30 PM Rob Herring <[email protected]> wrote:
>
> On Sat, Oct 17, 2020 at 05:38:57PM +0200, Fabien Parent wrote:
> > Some MediaTek SoC like MT8516 need to enable additional clocks
> > for the GPT timer. Enable them if present.
> >
> > Signed-off-by: Fabien Parent <[email protected]>
> > ---
> > drivers/clocksource/timer-mediatek.c | 12 ++++++++++++
> > 1 file changed, 12 insertions(+)
> >
> > diff --git a/drivers/clocksource/timer-mediatek.c b/drivers/clocksource/timer-mediatek.c
> > index 9318edcd8963..42e2d2090484 100644
> > --- a/drivers/clocksource/timer-mediatek.c
> > +++ b/drivers/clocksource/timer-mediatek.c
> > @@ -9,6 +9,7 @@
> >
> > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> >
> > +#include <linux/clk.h>
> > #include <linux/clockchips.h>
> > #include <linux/clocksource.h>
> > #include <linux/interrupt.h>
> > @@ -278,8 +279,19 @@ static int __init mtk_syst_init(struct device_node *node)
> >
> > static int __init mtk_gpt_init(struct device_node *node)
> > {
> > + struct clk *clk_13m, *clk_bus;
> > int ret;
> >
> > + /* Optional clock*/
>
> Then use the optional api variant.

I looked for optional API variant but could only find these:
* struct clk *devm_clk_get_optional(struct device *dev, const char *id);
* struct clk *devm_clk_get_optional(struct device *dev, const char *id);

These two require a "struct device" parameter but in the function
mtk_gpt_init, we only have a "struct device_node" I didn't see any way
to get a "struct device" from a "struct device_node".

>
> > + clk_13m = of_clk_get_by_name(node, "clk13m");
> > + if (!IS_ERR(clk_13m))
>
> And then you can drop this check (or handle it for any error other than
> clock is not present).
>
> > + clk_prepare_enable(clk_13m);
> > +
> > + /* Optional clock*/
> > + clk_bus = of_clk_get_by_name(node, "bus");
> > + if (!IS_ERR(clk_bus))
> > + clk_prepare_enable(clk_bus);
> > +
> > to.clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
> > to.clkevt.set_state_shutdown = mtk_gpt_clkevt_shutdown;
> > to.clkevt.set_state_periodic = mtk_gpt_clkevt_set_periodic;
> > --
> > 2.28.0
> >