Re: [PATCH 3/5] irqchip/bcm2836: Make IPIs use handle_percpu_devid_irq()

[Guenter Roeck]

Hi Marc,

On 12/15/20 2:19 AM, Marc Zyngier wrote:
> Hi Gunter,
> 
> On 2020-12-15 00:21, Guenter Roeck wrote:
>> On Mon, Nov 09, 2020 at 09:41:19AM +0000, Valentin Schneider wrote:
>>> As done for the Arm GIC irqchips, move IPIs to handle_percpu_devid_irq() as
>>> handle_percpu_devid_fasteoi_ipi() isn't actually required.
>>>
>>> Signed-off-by: Valentin Schneider <valentin.schneider@xxxxxxx>
>>
>> This patch results in boot failures (silent stall) for the qemu
>> raspi2 emulation. Unfortunately it can not be reverted because
>> handle_percpu_devid_fasteoi_ipi no longer exists in next-20201214,
>> so I don't know if it is the only problem.
> 
> This is odd. This works just fine for me on both the RPi2 and 3
> emulation, running a full Debian userspace. Could this be caused
> by the version of QEMU you are using? Here's what I have:
> 
> $ qemu-system-arm --version
> QEMU emulator version 5.1.0 (Debian 1:5.1+dfsg-4+b1)
> 

I used qemu 5.0 which - up to now - worked fine. Let me try with
5.1 and 5.2. Sorry, I should have tried first before bothering you.

Guenter

> Could you try the following hack and let me know if that helps?
> 
> Thanks,
> 
>         M.
> 
> diff --git a/drivers/irqchip/irq-bcm2836.c b/drivers/irqchip/irq-bcm2836.c
> index 5f5eb8877c41..25c9a9c06e41 100644
> --- a/drivers/irqchip/irq-bcm2836.c
> +++ b/drivers/irqchip/irq-bcm2836.c
> @@ -167,7 +167,7 @@ static void bcm2836_arm_irqchip_handle_ipi(struct irq_desc *desc)
>      chained_irq_exit(chip, desc);
>  }
> 
> -static void bcm2836_arm_irqchip_ipi_eoi(struct irq_data *d)
> +static void bcm2836_arm_irqchip_ipi_ack(struct irq_data *d)
>  {
>      int cpu = smp_processor_id();
> 
> @@ -195,7 +195,7 @@ static struct irq_chip bcm2836_arm_irqchip_ipi = {
>      .name        = "IPI",
>      .irq_mask    = bcm2836_arm_irqchip_dummy_op,
>      .irq_unmask    = bcm2836_arm_irqchip_dummy_op,
> -    .irq_eoi    = bcm2836_arm_irqchip_ipi_eoi,
> +    .irq_ack    = bcm2836_arm_irqchip_ipi_ack,
>      .ipi_send_mask    = bcm2836_arm_irqchip_ipi_send_mask,
>  };