Re: [PATCH] pinctrl: amd: Disable and mask interrupts on resume

[Kornel Dulęba]

On Tue, Apr 11, 2023 at 2:50 PM Linux regression tracking (Thorsten
Leemhuis) <regressions@xxxxxxxxxxxxx> wrote:
>
>
>
> On 10.04.23 17:29, Gong, Richard wrote:
> > On 4/10/2023 12:03 AM, Mario Limonciello wrote:
> >> On 3/20/23 04:32, Kornel Dulęba wrote:
> >>
> >>> This fixes a similar problem to the one observed in:
> >>> commit 4e5a04be88fe ("pinctrl: amd: disable and mask interrupts on
> >>> probe").
> >>>
> >>> On some systems, during suspend/resume cycle firmware leaves
> >>> an interrupt enabled on a pin that is not used by the kernel.
> >>> This confuses the AMD pinctrl driver and causes spurious interrupts.
> >>>
> >>> The driver already has logic to detect if a pin is used by the kernel.
> >>> Leverage it to re-initialize interrupt fields of a pin only if it's not
> >>> used by us.
> >>>
> >>> Signed-off-by: Kornel Dulęba <korneld@xxxxxxxxxxxx>
> >>> ---
> >>>   drivers/pinctrl/pinctrl-amd.c | 36 +++++++++++++++++++----------------
> >>>   1 file changed, 20 insertions(+), 16 deletions(-)
> >>>
> >>> diff --git a/drivers/pinctrl/pinctrl-amd.c
> >>> b/drivers/pinctrl/pinctrl-amd.c
> >>> index 9236a132c7ba..609821b756c2 100644
> >>> --- a/drivers/pinctrl/pinctrl-amd.c
> >>> +++ b/drivers/pinctrl/pinctrl-amd.c
> >>> @@ -872,32 +872,34 @@ static const struct pinconf_ops amd_pinconf_ops
> >>> = {
> >>>       .pin_config_group_set = amd_pinconf_group_set,
> >>>   };
> >>>   -static void amd_gpio_irq_init(struct amd_gpio *gpio_dev)
> >>> +static void amd_gpio_irq_init_pin(struct amd_gpio *gpio_dev, int pin)
> >>>   {
> >>> -    struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
> >>> +    const struct pin_desc *pd;
> >>>       unsigned long flags;
> >>>       u32 pin_reg, mask;
> >>> -    int i;
> >>>         mask = BIT(WAKE_CNTRL_OFF_S0I3) | BIT(WAKE_CNTRL_OFF_S3) |
> >>>           BIT(INTERRUPT_MASK_OFF) | BIT(INTERRUPT_ENABLE_OFF) |
> >>>           BIT(WAKE_CNTRL_OFF_S4);
> >>>   -    for (i = 0; i < desc->npins; i++) {
> >>> -        int pin = desc->pins[i].number;
> >>> -        const struct pin_desc *pd = pin_desc_get(gpio_dev->pctrl, pin);
> >>> -
> >>> -        if (!pd)
> >>> -            continue;
> >>> +    pd = pin_desc_get(gpio_dev->pctrl, pin);
> >>> +    if (!pd)
> >>> +        return;
> >>>   -        raw_spin_lock_irqsave(&gpio_dev->lock, flags);
> >>> +    raw_spin_lock_irqsave(&gpio_dev->lock, flags);
> >>> +    pin_reg = readl(gpio_dev->base + pin * 4);
> >>> +    pin_reg &= ~mask;
> >>> +    writel(pin_reg, gpio_dev->base + pin * 4);
> >>> +    raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
> >>> +}
> >>>   -        pin_reg = readl(gpio_dev->base + i * 4);
> >>> -        pin_reg &= ~mask;
> >>> -        writel(pin_reg, gpio_dev->base + i * 4);
> >>> +static void amd_gpio_irq_init(struct amd_gpio *gpio_dev)
> >>> +{
> >>> +    struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
> >>> +    int i;
> >>>   -        raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
> >>> -    }
> >>> +    for (i = 0; i < desc->npins; i++)
> >>> +        amd_gpio_irq_init_pin(gpio_dev, i);
> >>>   }
> >>>     #ifdef CONFIG_PM_SLEEP
> >>> @@ -950,8 +952,10 @@ static int amd_gpio_resume(struct device *dev)
> >>>       for (i = 0; i < desc->npins; i++) {
> >>>           int pin = desc->pins[i].number;
> >>>   -        if (!amd_gpio_should_save(gpio_dev, pin))
> >>> +        if (!amd_gpio_should_save(gpio_dev, pin)) {
> >>> +            amd_gpio_irq_init_pin(gpio_dev, pin);
> >>>               continue;
> >>> +        }
> >>>             raw_spin_lock_irqsave(&gpio_dev->lock, flags);
> >>>           gpio_dev->saved_regs[i] |= readl(gpio_dev->base + pin * 4)
> >>> & PIN_IRQ_PENDING;
> >>
> >> Hello Kornel,
> >>
> >> I've found that this commit which was included in 6.3-rc5 is causing a
> >> regression waking up from lid on a Lenovo Z13.
> > observed "unable to wake from power button" on AMD based Dell platform.
>
> This sounds like something that we want to fix quickly.
>
> > Reverting "pinctrl: amd: Disable and mask interrupts on resume" on the
> > top of 6.3-rc6 does fix the issue.
> >>
> >> Reverting it on top of 6.3-rc6 resolves the problem.
> >>
> >> I've collected what I can into this bug report:
> >>
> >> https://bugzilla.kernel.org/show_bug.cgi?id=217315
> >>
> >> Linus Walleij,
> >>
> >> It looks like this was CC to stable.  If we can't get a quick solution
> >> we might want to pull this from stable.
> >
> > this commit landed into 6.1.23 as well
> >
> >         d9c63daa576b2 pinctrl: amd: Disable and mask interrupts on resume
>
> It made it back up to 5.10.y afaics.
>
> The culprit has no fixes tag, which makes me wonder: should we quickly
> (e.g. today) revert this in mainline to get back to the previous state,
> so that Greg can pick up the revert for the next stable releases he
> apparently currently prepares?
>
> Greg, is there another way to make you quickly fix this in the stable
> trees? One option obviously would be "revert this now in stable, reapply
> it later together with a fix ". But I'm under the impression that this
> is too much of a hassle and thus something you only do in dire situations?
>
> I'm asking because I over time noticed that quite a few regressions are
> in a similar situation -- and quite a few of them take quite some time
> to get fixed even when a developer provided a fix, because reviewing and
> mainlining the fix takes a week or two (sometimes more). And that is a
> situation that is more and more hitting a nerve here. :-/

I've looked into this and at this moment I can't really find a quick fix.
See https://bugzilla.kernel.org/show_bug.cgi?id=217315#c3.
It seems that reverting this might be the best solution for now.

Regards
Kornel