Re: [PATCH v3 10/16] irqchip/bcm2836: Configure mailbox interrupts as standard interrupts

Marek Szyprowski
2020-09-14T19:13:19Z

Hi Marc,

On 14.09.2020 18:10, Marc Zyngier wrote:
> On 2020-09-14 15:32, Marek Szyprowski wrote:
>> On 01.09.2020 16:43, Marc Zyngier wrote:
>>> In order to switch the bcm2836 driver to privide standard interrupts
>>> for IPIs, it first needs to stop lying about the way things work.
>>>
>>> The mailbox interrupt is actually a multiplexer, with enough
>>> bits to store 32 pending interrupts per CPU. So let's turn it
>>> into a chained irqchip.
>>>
>>> Once this is done, we can instanciate the corresponding IPIs,
>>> and pass them to the architecture code.
>>>
>>> Signed-off-by: Marc Zyngier <maz@kernel.org>
>>
>> This one also fails. It breaks booting of Raspberry Pi 3b boards (both
>> in ARM and ARM64 mode):
>
> Damn. This used to work. Looks like I was eager to delete stuff at
> some point. Can you give this a go and let me know if that works
> for you (only tested in QEMU with the raspi2 model):
>
> diff --git a/drivers/irqchip/irq-bcm2836.c
> b/drivers/irqchip/irq-bcm2836.c
> index 85df6ddad9be..97838eb705f9 100644
> --- a/drivers/irqchip/irq-bcm2836.c
> +++ b/drivers/irqchip/irq-bcm2836.c
> @@ -193,6 +193,8 @@ static void
> bcm2836_arm_irqchip_ipi_send_mask(struct irq_data *d,
>
>  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,
>      .ipi_send_mask    = bcm2836_arm_irqchip_ipi_send_mask,
>  };
>
>
> Thanks again,

This fixes boot on my RPi3b. Thanks!

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland