diff mbox

[1/5] clocksource: mediatek: do not enable GPT_CLK_EVT when setup

Message ID 1436779969-18610-2-git-send-email-yingjoe.chen@mediatek.com (mailing list archive)
State New, archived
Headers show

Commit Message

Yingjoe Chen July 13, 2015, 9:32 a.m. UTC
Spurious mtk timer interrupt is noticed at boot and cause kernel
crash. It seems if GPT is enabled, it will latch irq status even
when its IRQ is disabled. When irq is enabled afterward, we see
spurious interrupt.
Change init flow to only enable GPT_CLK_SRC at mtk_timer_init.

Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
---
 drivers/clocksource/mtk_timer.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

Comments

Daniel Kurtz July 14, 2015, 7:39 a.m. UTC | #1
Hi Yingjoe,

On Mon, Jul 13, 2015 at 5:32 PM, Yingjoe Chen <yingjoe.chen@mediatek.com> wrote:
> Spurious mtk timer interrupt is noticed at boot and cause kernel
> crash. It seems if GPT is enabled, it will latch irq status even
> when its IRQ is disabled. When irq is enabled afterward, we see
> spurious interrupt.
> Change init flow to only enable GPT_CLK_SRC at mtk_timer_init.
>
> Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
> ---
>  drivers/clocksource/mtk_timer.c | 16 ++++++++++------
>  1 file changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c
> index 68ab423..237c20b 100644
> --- a/drivers/clocksource/mtk_timer.c
> +++ b/drivers/clocksource/mtk_timer.c
> @@ -156,9 +156,11 @@ static void mtk_timer_global_reset(struct mtk_clock_event_device *evt)
>         writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG);
>  }
>
> -static void
> -mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option)
> +static void mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer,
> +                           u8 option, bool enable)

This function can be: __init

Other than this tiny nit, and the small potential conflict in patch 4,
this whole series is:

Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>

(I do think it is a bit strange that the mediatek,mt6577-timer binding
does not use "clock-names", but that is independent of this patch
set).

Thanks!


>  {
> +       u32 val;
> +
>         writel(TIMER_CTRL_CLEAR | TIMER_CTRL_DISABLE,
>                 evt->gpt_base + TIMER_CTRL_REG(timer));
>
> @@ -167,8 +169,10 @@ mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option)
>
>         writel(0x0, evt->gpt_base + TIMER_CMP_REG(timer));
>
> -       writel(TIMER_CTRL_OP(option) | TIMER_CTRL_ENABLE,
> -                       evt->gpt_base + TIMER_CTRL_REG(timer));
> +       val = TIMER_CTRL_OP(option);
> +       if (enable)
> +               val |= TIMER_CTRL_ENABLE;
> +       writel(val, evt->gpt_base + TIMER_CTRL_REG(timer));
>  }
>
>  static void mtk_timer_enable_irq(struct mtk_clock_event_device *evt, u8 timer)
> @@ -235,12 +239,12 @@ static void __init mtk_timer_init(struct device_node *node)
>         evt->ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
>
>         /* Configure clock source */
> -       mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN);
> +       mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN, true);
>         clocksource_mmio_init(evt->gpt_base + TIMER_CNT_REG(GPT_CLK_SRC),
>                         node->name, rate, 300, 32, clocksource_mmio_readl_up);
>
>         /* Configure clock event */
> -       mtk_timer_setup(evt, GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT);
> +       mtk_timer_setup(evt, GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT, false);
>         clockevents_config_and_register(&evt->dev, rate, 0x3,
>                                         0xffffffff);
>
> --
> 1.8.1.1.dirty
>
Matthias Brugger July 17, 2015, 9:56 p.m. UTC | #2
On Monday, July 13, 2015 05:32:45 PM Yingjoe Chen wrote:
> Spurious mtk timer interrupt is noticed at boot and cause kernel
> crash. It seems if GPT is enabled, it will latch irq status even
> when its IRQ is disabled. When irq is enabled afterward, we see
> spurious interrupt.
> Change init flow to only enable GPT_CLK_SRC at mtk_timer_init.
> 
> Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
> ---

Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
Yingjoe Chen July 22, 2015, 8:24 a.m. UTC | #3
On Tue, 2015-07-14 at 15:39 +0800, Daniel Kurtz wrote:
> Hi Yingjoe,
> 
> On Mon, Jul 13, 2015 at 5:32 PM, Yingjoe Chen <yingjoe.chen@mediatek.com> wrote:
> > Spurious mtk timer interrupt is noticed at boot and cause kernel
> > crash. It seems if GPT is enabled, it will latch irq status even
> > when its IRQ is disabled. When irq is enabled afterward, we see
> > spurious interrupt.
> > Change init flow to only enable GPT_CLK_SRC at mtk_timer_init.
> >
> > Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
> > ---
> >  drivers/clocksource/mtk_timer.c | 16 ++++++++++------
> >  1 file changed, 10 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c
> > index 68ab423..237c20b 100644
> > --- a/drivers/clocksource/mtk_timer.c
> > +++ b/drivers/clocksource/mtk_timer.c
> > @@ -156,9 +156,11 @@ static void mtk_timer_global_reset(struct mtk_clock_event_device *evt)
> >         writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG);
> >  }
> >
> > -static void
> > -mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option)
> > +static void mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer,
> > +                           u8 option, bool enable)
> 
> This function can be: __init
> 
> Other than this tiny nit, and the small potential conflict in patch 4,
> this whole series is:
> 
> Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
> 
> (I do think it is a bit strange that the mediatek,mt6577-timer binding
> does not use "clock-names", but that is independent of this patch
> set).
> 


Hi Daniel,

Thanks for your review.

I added __init as you suggested, and Pi-Cheng already sent an updated
version of his patch to resolve the conflict[1].

Joe.C

[1]
http://lists.infradead.org/pipermail/linux-mediatek/2015-July/001592.html
diff mbox

Patch

diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c
index 68ab423..237c20b 100644
--- a/drivers/clocksource/mtk_timer.c
+++ b/drivers/clocksource/mtk_timer.c
@@ -156,9 +156,11 @@  static void mtk_timer_global_reset(struct mtk_clock_event_device *evt)
 	writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG);
 }
 
-static void
-mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option)
+static void mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer,
+			    u8 option, bool enable)
 {
+	u32 val;
+
 	writel(TIMER_CTRL_CLEAR | TIMER_CTRL_DISABLE,
 		evt->gpt_base + TIMER_CTRL_REG(timer));
 
@@ -167,8 +169,10 @@  mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option)
 
 	writel(0x0, evt->gpt_base + TIMER_CMP_REG(timer));
 
-	writel(TIMER_CTRL_OP(option) | TIMER_CTRL_ENABLE,
-			evt->gpt_base + TIMER_CTRL_REG(timer));
+	val = TIMER_CTRL_OP(option);
+	if (enable)
+		val |= TIMER_CTRL_ENABLE;
+	writel(val, evt->gpt_base + TIMER_CTRL_REG(timer));
 }
 
 static void mtk_timer_enable_irq(struct mtk_clock_event_device *evt, u8 timer)
@@ -235,12 +239,12 @@  static void __init mtk_timer_init(struct device_node *node)
 	evt->ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
 
 	/* Configure clock source */
-	mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN);
+	mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN, true);
 	clocksource_mmio_init(evt->gpt_base + TIMER_CNT_REG(GPT_CLK_SRC),
 			node->name, rate, 300, 32, clocksource_mmio_readl_up);
 
 	/* Configure clock event */
-	mtk_timer_setup(evt, GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT);
+	mtk_timer_setup(evt, GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT, false);
 	clockevents_config_and_register(&evt->dev, rate, 0x3,
 					0xffffffff);