Re: [PATCH v11 09/14] irqchip/riscv-imsic: Add support for PCI MSI irqdomain

[Björn Töpel]

Anup Patel <apatel@xxxxxxxxxxxxxxxx> writes:

> The Linux PCI framework requires it's own dedicated MSI irqdomain so
> let us create PCI MSI irqdomain as child of the IMSIC base irqdomain.
>
> Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
> ---
>  drivers/irqchip/Kconfig                    |  7 +++
>  drivers/irqchip/irq-riscv-imsic-platform.c | 51 ++++++++++++++++++++++
>  drivers/irqchip/irq-riscv-imsic-state.h    |  1 +
>  3 files changed, 59 insertions(+)
>
> diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
> index bdd80716114d..c1d69b418dfb 100644
> --- a/drivers/irqchip/Kconfig
> +++ b/drivers/irqchip/Kconfig
> @@ -552,6 +552,13 @@ config RISCV_IMSIC
>  	select IRQ_DOMAIN_HIERARCHY
>  	select GENERIC_MSI_IRQ
>  
> +config RISCV_IMSIC_PCI
> +	bool
> +	depends on RISCV_IMSIC
> +	depends on PCI
> +	depends on PCI_MSI
> +	default RISCV_IMSIC
> +
>  config EXYNOS_IRQ_COMBINER
>  	bool "Samsung Exynos IRQ combiner support" if COMPILE_TEST
>  	depends on (ARCH_EXYNOS && ARM) || COMPILE_TEST
> diff --git a/drivers/irqchip/irq-riscv-imsic-platform.c b/drivers/irqchip/irq-riscv-imsic-platform.c
> index 23d286cb017e..cdb659401199 100644
> --- a/drivers/irqchip/irq-riscv-imsic-platform.c
> +++ b/drivers/irqchip/irq-riscv-imsic-platform.c
> @@ -13,6 +13,7 @@
>  #include <linux/irqdomain.h>
>  #include <linux/module.h>
>  #include <linux/msi.h>
> +#include <linux/pci.h>
>  #include <linux/platform_device.h>
>  #include <linux/spinlock.h>
>  #include <linux/smp.h>
> @@ -215,6 +216,42 @@ static const struct irq_domain_ops imsic_base_domain_ops = {
>  #endif
>  };
>  
> +#ifdef CONFIG_RISCV_IMSIC_PCI
> +
> +static void imsic_pci_mask_irq(struct irq_data *d)
> +{
> +	pci_msi_mask_irq(d);
> +	irq_chip_mask_parent(d);

I've asked this before, but I still don't get why you need to propagate
to the parent? Why isn't masking on PCI enough?


Björn