Re: Interrupt storm from pinctrl-amd on Acer AN515-42
On Fri, 28 Dec 2018, Linus Walleij wrote: > On Fri, Dec 28, 2018 at 12:02 AM Leonard Crestez wrote: > > > Digging a little deeper it seems the touchpad interrupt is active on > > boot and since it's configured as "level" and no touchpad driver is > > available yet there does not seem to be any way to clear it. > > I think these are called "spurious interrupts". > > > I don't know how this should be handled, booting with an active enabled but > > unclearable interrupt seems like a platform bug to me. There is even an > > option to set touchpad to "basic" which does some sort of ps2 emulation > > but the IRQ issue still happens! > > > > One workaround is to explicitly disable the interrupt from the handler > > if no mapping is found; this will keep it disabled until > > amd_gpio_irq_set_type is called later. > > I don't know how x86 and ACPI systems usually deal with this stuff > so I'm kind of lost. On the embedded systems that I develop on, > I would just disable all interrupts on probe() (usually writing 0x0 in > some interrupt enable register) and then they will get enabled > once consumers need them. That's the right thing to do. > But I have come to understand that maybe ACPI systems are > not so happy about drivers doing things like that? Each driver has to invoke a request_irq() variant, which enables the interrupt line. So there should be no problem when disabling all interrupts on probe. Thanks, tglx
Re: Interrupt storm from pinctrl-amd on Acer AN515-42
On Fri, Dec 28, 2018 at 12:02 AM Leonard Crestez wrote: > Digging a little deeper it seems the touchpad interrupt is active on > boot and since it's configured as "level" and no touchpad driver is > available yet there does not seem to be any way to clear it. I think these are called "spurious interrupts". > I don't know how this should be handled, booting with an active enabled but > unclearable interrupt seems like a platform bug to me. There is even an > option to set touchpad to "basic" which does some sort of ps2 emulation > but the IRQ issue still happens! > > One workaround is to explicitly disable the interrupt from the handler > if no mapping is found; this will keep it disabled until > amd_gpio_irq_set_type is called later. I don't know how x86 and ACPI systems usually deal with this stuff so I'm kind of lost. On the embedded systems that I develop on, I would just disable all interrupts on probe() (usually writing 0x0 in some interrupt enable register) and then they will get enabled once consumers need them. But I have come to understand that maybe ACPI systems are not so happy about drivers doing things like that? Yours, Linus Walleij
Interrupt storm from pinctrl-amd on Acer AN515-42
Hello, My Acer Nitro 5 AN515-42 laptop with a Ryzen 2700U hangs on boot with recent kernel on an interrupt storm from pinctrl-amd. Older kernels work but this seems to be because this module was disabled by default. I tried to copy over old driver from 4.9 but it still experiences same issue. Digging a little deeper it seems the touchpad interrupt is active on boot and since it's configured as "level" and no touchpad driver is available yet there does not seem to be any way to clear it. I don't know how this should be handled, booting with an active enabled but unclearable interrupt seems like a platform bug to me. There is even an option to set touchpad to "basic" which does some sort of ps2 emulation but the IRQ issue still happens! One workaround is to explicitly disable the interrupt from the handler if no mapping is found; this will keep it disabled until amd_gpio_irq_set_type is called later. --- drivers/pinctrl/pinctrl-amd.c +++ drivers/pinctrl/pinctrl-amd.c @@ -567,22 +567,27 @@ static irqreturn_t amd_gpio_irq_handler(int irq, void *dev_id) regval = readl(regs + i); if (!(regval & PIN_IRQ_PENDING) || !(regval & BIT(INTERRUPT_MASK_OFF))) continue; irq = irq_find_mapping(gc->irq.domain, irqnr + i); - generic_handle_irq(irq); + if (irq) { + generic_handle_irq(irq); + ret = IRQ_HANDLED; + } /* Clear interrupt. * We must read the pin register again, in case the * value was changed while executing * generic_handle_irq() above. */ raw_spin_lock_irqsave(&gpio_dev->lock, flags); regval = readl(regs + i); + /* Disable if pending but unmapped */ + if (!irq && (regval & PIN_IRQ_PENDING)) + regval &= ~BIT(INTERRUPT_ENABLE_OFF); writel(regval, regs + i); raw_spin_unlock_irqrestore(&gpio_dev->lock, flags); - ret = IRQ_HANDLED; } } /* Signal EOI to the GPIO unit */ When in "i2c mode" the touchpad has an ACPI hid "ELAN0504", there are many similar compatibe hids in elan_i2c driver and if I add this one it probes successfully and handles irqs but fails to report input (i2c read data is invalid). Same laptop experiences some severe p-state throttling issues so there are many things wrong here. Let me know if you want more version info or ACPI dumps. -- Regards, Leonard