[PATCH V12 1/3] ACPI: Generic GSI: Do not attempt to map non-GSI IRQs during bus scan

[Lorenzo Pieralisi]

On Thu, Feb 02, 2017 at 06:23:57PM -0500, Agustin Vega-Frias wrote:
> ACPI extended IRQ resources may contain a Resource Source field to specify
> an alternate interrupt controller, attempting to map them as GSIs is
> incorrect, so just disable the platform resource.
> 
> Since this field is currently ignored, we make this change conditional
> on CONFIG_ACPI_GENERIC_GSI to keep the current behavior on x86 platforms,
> in case some existing ACPI tables are using this incorrectly.
> 
> Acked-by: Rafael J. Wysocki <rafael at kernel.org>
> Signed-off-by: Agustin Vega-Frias <agustinv at codeaurora.org>
> ---
>  drivers/acpi/resource.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)

Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>

> diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
> index cb57962..8b11d6d 100644
> --- a/drivers/acpi/resource.c
> +++ b/drivers/acpi/resource.c
> @@ -43,6 +43,19 @@ static inline bool acpi_iospace_resource_valid(struct resource *res)
>  acpi_iospace_resource_valid(struct resource *res) { return true; }
>  #endif
>  
> +#if IS_ENABLED(CONFIG_ACPI_GENERIC_GSI)
> +static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
> +{
> +	return ext_irq->resource_source.string_length == 0 &&
> +	       ext_irq->producer_consumer == ACPI_CONSUMER;
> +}
> +#else
> +static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
> +{
> +	return true;
> +}
> +#endif
> +
>  static bool acpi_dev_resource_len_valid(u64 start, u64 end, u64 len, bool io)
>  {
>  	u64 reslen = end - start + 1;
> @@ -470,9 +483,12 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
>  			acpi_dev_irqresource_disabled(res, 0);
>  			return false;
>  		}
> -		acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
> +		if (is_gsi(ext_irq))
> +			acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
>  					 ext_irq->triggering, ext_irq->polarity,
>  					 ext_irq->sharable, false);
> +		else
> +			acpi_dev_irqresource_disabled(res, 0);
>  		break;
>  	default:
>  		res->flags = 0;
> -- 
> Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
> Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
>