Subject: Re: [PATCH v2] powerpc: 52xx: nop out unsupported critical IRQs

From: Wolfram Sang <[email-masked]>
Date: Sat, 20 Oct 2012 08:54:42 +0200

On Thu, Oct 11, 2012 at 11:19:15AM +0200, Wolfram Sang wrote:
> Currently, when booting MPC52xx based platforms, we get:
> 
>         mpc52xx_irqhost_map: invalid irq: virq=16, l1=0, l2=3
>         irq: irq-16==>hwirq-0x3 mapping failed: -22
>         [WARNing skipped]
> 
> The warning is wrong since the mapping itself is valid. However, there is no
> support for that type of IRQ currently. Print a proper warning and bind the irq
> to a no_irq chip.
> 
> Signed-off-by: Wolfram Sang <[email-masked]>
> Cc: John Bonesio <[email-masked]>
> Cc: Anatolij Gustschin <[email-masked]>
> Cc: Grant Likely <[email-masked]>

Ping. I'd really like to get rid of the WARNing for all MPC52xx boards.
It looks pretty scary to people who don't know the issues behind it.

> ---
> 
> Change since V1: drop the default state since all possibilities for l1 are now
> 		 covered in the switch-statement.
> 
>  arch/powerpc/platforms/52xx/mpc52xx_pic.c |    9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/52xx/mpc52xx_pic.c b/arch/powerpc/platforms/52xx/mpc52xx_pic.c
> index 8520b58..b89ef65 100644
> --- a/arch/powerpc/platforms/52xx/mpc52xx_pic.c
> +++ b/arch/powerpc/platforms/52xx/mpc52xx_pic.c
> @@ -372,10 +372,11 @@ static int mpc52xx_irqhost_map(struct irq_domain *h, unsigned int virq,
>  	case MPC52xx_IRQ_L1_MAIN: irqchip = &mpc52xx_main_irqchip; break;
>  	case MPC52xx_IRQ_L1_PERP: irqchip = &mpc52xx_periph_irqchip; break;
>  	case MPC52xx_IRQ_L1_SDMA: irqchip = &mpc52xx_sdma_irqchip; break;
> -	default:
> -		pr_err("%s: invalid irq: virq=%i, l1=%i, l2=%i\n",
> -		       __func__, virq, l1irq, l2irq);
> -		return -EINVAL;
> +	case MPC52xx_IRQ_L1_CRIT:
> +		pr_warn("%s: Critical IRQ #%d is unsupported! Nopping it.\n",
> +			__func__, l2irq);
> +		irq_set_chip(virq, &no_irq_chip);
> +		return 0;
>  	}
>  
>  	irq_set_chip_and_handler(virq, irqchip, handle_level_irq);
> -- 
> 1.7.10.4
> 

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