| Message ID | 1617960162-1988-2-git-send-email-Fengquan.Chen@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4,1/1] clocksource/drivers/timer-mediatek: optimize systimer irq clear flow on shutdown | expand |
On Fri, Apr 9, 2021 at 5:22 PM Fengquan Chen <Fengquan.Chen@mediatek.com> wrote: > > mtk_syst_clkevt_shutdown is called after irq disabled in suspend flow, > clear any pending systimer irq when shutdown to avoid suspend aborted > due to timer irq pending > > Also as for systimer in mediatek socs, there must be firstly enable > timer before clear systimer irq > > Fixes: e3af677607d9("clocksource/drivers/timer-mediatek: Add support for system timer") > Signed-off-by: Fengquan Chen <fengquan.chen@mediatek.com> > Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested on a mt8183 device. This patch solves an issue that device would hang on resume during genpd_resume_noirq: [ 724.342834] mtk-smi-larb 17010000.larb: genpd_resume_noirq+0x0/0xd0 returned 0 after 976593 usecs [ 724.351721] mtk-smi-larb 1a001000.larb: calling genpd_resume_noirq+0x0/0xd0 @ 6629, parent: soc [ 736.845047] Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 3 [ 736.852268] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G W 5.10.26 #17 [ 736.859743] Hardware name: MediaTek krane sku176 board (DT) [ 736.865309] Call trace: [ 736.867756] dump_backtrace+0x0/0x1bc [ 736.871415] show_stack+0x20/0x2c [ 736.874728] dump_stack+0xc0/0x11c [ 736.878124] panic+0x174/0x378 [ 736.881178] watchdog_check_hardlockup+0x11c/0x124 [ 736.885963] watchdog_timer_fn+0x70/0x274 <snip> > --- > drivers/clocksource/timer-mediatek.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/clocksource/timer-mediatek.c b/drivers/clocksource/timer-mediatek.c > index 9318edc..6461fd3 100644 > --- a/drivers/clocksource/timer-mediatek.c > +++ b/drivers/clocksource/timer-mediatek.c > @@ -60,9 +60,9 @@ > * SYST_CON_EN: Clock enable. Shall be set to > * - Start timer countdown. > * - Allow timeout ticks being updated. > - * - Allow changing interrupt functions. > + * - Allow changing interrupt status,like clear irq pending. > * > - * SYST_CON_IRQ_EN: Set to allow interrupt. > + * SYST_CON_IRQ_EN: Set to enable interrupt. > * > * SYST_CON_IRQ_CLR: Set to clear interrupt. > */ > @@ -75,6 +75,7 @@ > static void mtk_syst_ack_irq(struct timer_of *to) > { > /* Clear and disable interrupt */ > + writel(SYST_CON_EN, SYST_CON_REG(to)); > writel(SYST_CON_IRQ_CLR | SYST_CON_EN, SYST_CON_REG(to)); > } > > @@ -111,6 +112,9 @@ static int mtk_syst_clkevt_next_event(unsigned long ticks, > > static int mtk_syst_clkevt_shutdown(struct clock_event_device *clkevt) > { > + /* Clear any irq */ > + mtk_syst_ack_irq(to_timer_of(clkevt)); > + > /* Disable timer */ > writel(0, SYST_CON_REG(to_timer_of(clkevt))); > > -- > 1.8.1.1.dirty >
On 09/04/2021 11:22, Fengquan Chen wrote: > mtk_syst_clkevt_shutdown is called after irq disabled in suspend flow, > clear any pending systimer irq when shutdown to avoid suspend aborted > due to timer irq pending > > Also as for systimer in mediatek socs, there must be firstly enable > timer before clear systimer irq > > Fixes: e3af677607d9("clocksource/drivers/timer-mediatek: Add support for system timer") > Signed-off-by: Fengquan Chen <fengquan.chen@mediatek.com> > > --- > drivers/clocksource/timer-mediatek.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/clocksource/timer-mediatek.c b/drivers/clocksource/timer-mediatek.c > index 9318edc..6461fd3 100644 > --- a/drivers/clocksource/timer-mediatek.c > +++ b/drivers/clocksource/timer-mediatek.c > @@ -60,9 +60,9 @@ > * SYST_CON_EN: Clock enable. Shall be set to > * - Start timer countdown. > * - Allow timeout ticks being updated. > - * - Allow changing interrupt functions. > + * - Allow changing interrupt status,like clear irq pending. > * > - * SYST_CON_IRQ_EN: Set to allow interrupt. > + * SYST_CON_IRQ_EN: Set to enable interrupt. > * > * SYST_CON_IRQ_CLR: Set to clear interrupt. > */ > @@ -75,6 +75,7 @@ > static void mtk_syst_ack_irq(struct timer_of *to) > { > /* Clear and disable interrupt */ > + writel(SYST_CON_EN, SYST_CON_REG(to)); > writel(SYST_CON_IRQ_CLR | SYST_CON_EN, SYST_CON_REG(to)); > } IIRC, there is a hardware issue here. If it is the case, please describe it and refer to an errata if any. Also Evan Benn commented your code and asked a couple of questions [1], please answer before reposting a new version. Comments ignored == patch ignored > @@ -111,6 +112,9 @@ static int mtk_syst_clkevt_next_event(unsigned long ticks, > > static int mtk_syst_clkevt_shutdown(struct clock_event_device *clkevt) > { > + /* Clear any irq */ > + mtk_syst_ack_irq(to_timer_of(clkevt)); > + > /* Disable timer */ > writel(0, SYST_CON_REG(to_timer_of(clkevt))); Please check out the patch sent by Evan Benn [2], if you agree, ack it. Thanks -- Daniel [1] https://patchwork.kernel.org/comment/24059277/ [2] https://lore.kernel.org/linux-arm-kernel/20210412132200.v3.1.I1d9917047de06715da16e1620759f703fcfdcbcb@changeid/
On Mon, 2021-04-19 at 10:44 +0200, Daniel Lezcano wrote: > On 09/04/2021 11:22, Fengquan Chen wrote: > > mtk_syst_clkevt_shutdown is called after irq disabled in suspend flow, > > clear any pending systimer irq when shutdown to avoid suspend aborted > > due to timer irq pending > > > > Also as for systimer in mediatek socs, there must be firstly enable > > timer before clear systimer irq > > > > Fixes: e3af677607d9("clocksource/drivers/timer-mediatek: Add support for system timer") > > Signed-off-by: Fengquan Chen <fengquan.chen@mediatek.com> > > > > --- > > drivers/clocksource/timer-mediatek.c | 8 ++++++-- > > 1 file changed, 6 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/clocksource/timer-mediatek.c b/drivers/clocksource/timer-mediatek.c > > index 9318edc..6461fd3 100644 > > --- a/drivers/clocksource/timer-mediatek.c > > +++ b/drivers/clocksource/timer-mediatek.c > > @@ -60,9 +60,9 @@ > > * SYST_CON_EN: Clock enable. Shall be set to > > * - Start timer countdown. > > * - Allow timeout ticks being updated. > > - * - Allow changing interrupt functions. > > + * - Allow changing interrupt status,like clear irq pending. > > * > > - * SYST_CON_IRQ_EN: Set to allow interrupt. > > + * SYST_CON_IRQ_EN: Set to enable interrupt. > > * > > * SYST_CON_IRQ_CLR: Set to clear interrupt. > > */ > > @@ -75,6 +75,7 @@ > > static void mtk_syst_ack_irq(struct timer_of *to) > > { > > /* Clear and disable interrupt */ > > + writel(SYST_CON_EN, SYST_CON_REG(to)); > > writel(SYST_CON_IRQ_CLR | SYST_CON_EN, SYST_CON_REG(to)); > > } > > IIRC, there is a hardware issue here. If it is the case, please describe > it and refer to an errata if any. Thanks for review. here is just a hw config flow limitation, not a bug. > > Also Evan Benn commented your code and asked a couple of questions [1], > please answer before reposting a new version. > > Comments ignored == patch ignored Thanks. i have answered by mail before, but it didn't uploaded to the list. has been uploaded ok now. > > > @@ -111,6 +112,9 @@ static int mtk_syst_clkevt_next_event(unsigned long ticks, > > > > static int mtk_syst_clkevt_shutdown(struct clock_event_device *clkevt) > > { > > + /* Clear any irq */ > > + mtk_syst_ack_irq(to_timer_of(clkevt)); > > + > > /* Disable timer */ > > writel(0, SYST_CON_REG(to_timer_of(clkevt))); > > Please check out the patch sent by Evan Benn [2], if you agree, ack it. > Thanks agree > Thanks > > -- Daniel > > [1] https://patchwork.kernel.org/comment/24059277/ > [2] > https://lore.kernel.org/linux-arm-kernel/20210412132200.v3.1.I1d9917047de06715da16e1620759f703fcfdcbcb@changeid/ >
hi Daniel, Gentle pin for this patch. Thanks Best Regards Fengquan On Wed, 2021-04-21 at 18:27 +0800, Fengquan Chen wrote: > On Mon, 2021-04-19 at 10:44 +0200, Daniel Lezcano wrote: > > On 09/04/2021 11:22, Fengquan Chen wrote: > > > mtk_syst_clkevt_shutdown is called after irq disabled in suspend flow, > > > clear any pending systimer irq when shutdown to avoid suspend aborted > > > due to timer irq pending > > > > > > Also as for systimer in mediatek socs, there must be firstly enable > > > timer before clear systimer irq > > > > > > Fixes: e3af677607d9("clocksource/drivers/timer-mediatek: Add support for system timer") > > > Signed-off-by: Fengquan Chen <fengquan.chen@mediatek.com> > > > > > > --- > > > drivers/clocksource/timer-mediatek.c | 8 ++++++-- > > > 1 file changed, 6 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/clocksource/timer-mediatek.c b/drivers/clocksource/timer-mediatek.c > > > index 9318edc..6461fd3 100644 > > > --- a/drivers/clocksource/timer-mediatek.c > > > +++ b/drivers/clocksource/timer-mediatek.c > > > @@ -60,9 +60,9 @@ > > > * SYST_CON_EN: Clock enable. Shall be set to > > > * - Start timer countdown. > > > * - Allow timeout ticks being updated. > > > - * - Allow changing interrupt functions. > > > + * - Allow changing interrupt status,like clear irq pending. > > > * > > > - * SYST_CON_IRQ_EN: Set to allow interrupt. > > > + * SYST_CON_IRQ_EN: Set to enable interrupt. > > > * > > > * SYST_CON_IRQ_CLR: Set to clear interrupt. > > > */ > > > @@ -75,6 +75,7 @@ > > > static void mtk_syst_ack_irq(struct timer_of *to) > > > { > > > /* Clear and disable interrupt */ > > > + writel(SYST_CON_EN, SYST_CON_REG(to)); > > > writel(SYST_CON_IRQ_CLR | SYST_CON_EN, SYST_CON_REG(to)); > > > } > > > > IIRC, there is a hardware issue here. If it is the case, please describe > > it and refer to an errata if any. > > Thanks for review. > here is just a hw config flow limitation, not a bug. > > > > > Also Evan Benn commented your code and asked a couple of questions [1], > > please answer before reposting a new version. > > > > Comments ignored == patch ignored > > Thanks. i have answered by mail before, but it didn't uploaded to the > list. has been uploaded ok now. > > > > > > @@ -111,6 +112,9 @@ static int mtk_syst_clkevt_next_event(unsigned long ticks, > > > > > > static int mtk_syst_clkevt_shutdown(struct clock_event_device *clkevt) > > > { > > > + /* Clear any irq */ > > > + mtk_syst_ack_irq(to_timer_of(clkevt)); > > > + > > > /* Disable timer */ > > > writel(0, SYST_CON_REG(to_timer_of(clkevt))); > > > > Please check out the patch sent by Evan Benn [2], if you agree, ack it. > > > > Thanks > > agree > > > Thanks > > > > -- Daniel > > > > [1] https://patchwork.kernel.org/comment/24059277/ > > [2] > > https://lore.kernel.org/linux-arm-kernel/20210412132200.v3.1.I1d9917047de06715da16e1620759f703fcfdcbcb@changeid/ > > >
diff --git a/drivers/clocksource/timer-mediatek.c b/drivers/clocksource/timer-mediatek.c index 9318edc..6461fd3 100644 --- a/drivers/clocksource/timer-mediatek.c +++ b/drivers/clocksource/timer-mediatek.c @@ -60,9 +60,9 @@ * SYST_CON_EN: Clock enable. Shall be set to * - Start timer countdown. * - Allow timeout ticks being updated. - * - Allow changing interrupt functions. + * - Allow changing interrupt status,like clear irq pending. * - * SYST_CON_IRQ_EN: Set to allow interrupt. + * SYST_CON_IRQ_EN: Set to enable interrupt. * * SYST_CON_IRQ_CLR: Set to clear interrupt. */ @@ -75,6 +75,7 @@ static void mtk_syst_ack_irq(struct timer_of *to) { /* Clear and disable interrupt */ + writel(SYST_CON_EN, SYST_CON_REG(to)); writel(SYST_CON_IRQ_CLR | SYST_CON_EN, SYST_CON_REG(to)); } @@ -111,6 +112,9 @@ static int mtk_syst_clkevt_next_event(unsigned long ticks, static int mtk_syst_clkevt_shutdown(struct clock_event_device *clkevt) { + /* Clear any irq */ + mtk_syst_ack_irq(to_timer_of(clkevt)); + /* Disable timer */ writel(0, SYST_CON_REG(to_timer_of(clkevt)));
mtk_syst_clkevt_shutdown is called after irq disabled in suspend flow, clear any pending systimer irq when shutdown to avoid suspend aborted due to timer irq pending Also as for systimer in mediatek socs, there must be firstly enable timer before clear systimer irq Fixes: e3af677607d9("clocksource/drivers/timer-mediatek: Add support for system timer") Signed-off-by: Fengquan Chen <fengquan.chen@mediatek.com> --- drivers/clocksource/timer-mediatek.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)