Re: [PATCH 08/18] Delayed frv setup of PCI IRQs to bus scan time

[Bjorn Helgaas <bhelgaas@google.com>]

On Thu, Oct 02, 2014 at 05:07:36AM +0100, matt@masarand.com wrote:
> From: Matthew Minter <matt@masarand.com>
> 
> PCI IRQs are being assigned during the frv pcibios phase. This causes
> devices which are not connected at boot but are later hot-plugged
> to not receive an IRQ. This patch set causes the pcibios to instead
> register an IRQ assignment function which is called during the enable
> device path to apply to all devices.
> 
> Signed-off-by: Matthew Minter <matt@masarand.com>
> 
> ---
>  arch/frv/mb93090-mb00/pci-frv.h |  1 -
>  arch/frv/mb93090-mb00/pci-irq.c | 28 +++++++++++++++++-----------
>  arch/frv/mb93090-mb00/pci-vdk.c |  1 -
>  3 files changed, 17 insertions(+), 13 deletions(-)
> 
> diff --git a/arch/frv/mb93090-mb00/pci-frv.h b/arch/frv/mb93090-mb00/pci-frv.h
> index a7e487fe..492b56d 100644
> --- a/arch/frv/mb93090-mb00/pci-frv.h
> +++ b/arch/frv/mb93090-mb00/pci-frv.h
> @@ -36,5 +36,4 @@ extern struct pci_ops *__nongpreldata pci_root_ops;
>  extern unsigned int pcibios_irq_mask;
>  
>  void pcibios_irq_init(void);
> -void pcibios_fixup_irqs(void);
>  void pcibios_enable_irq(struct pci_dev *dev);
> diff --git a/arch/frv/mb93090-mb00/pci-irq.c b/arch/frv/mb93090-mb00/pci-irq.c
> index 1c35c93..3463e30 100644
> --- a/arch/frv/mb93090-mb00/pci-irq.c
> +++ b/arch/frv/mb93090-mb00/pci-irq.c
> @@ -40,19 +40,25 @@ void __init pcibios_irq_init(void)
>  {
>  }
>  
> -void __init pcibios_fixup_irqs(void)
> +int pcibios_map_irq(struct pci_dev *dev, uint8_t slot, uint8_t pin)
>  {
> -	struct pci_dev *dev = NULL;
> -	uint8_t line, pin;
> -
> -	for_each_pci_dev(dev) {
> -		pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
> -		if (pin) {
> -			dev->irq = pci_bus0_irq_routing[PCI_SLOT(dev->devfn)][pin - 1];
> -			pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
> -		}
> -		pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &line);
> +	uint8_t line;
> +	int irq;
> +
> +	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);

Doesn't your common code always read PCI_INTERRUPT_PIN and pass it in, so
you wouldn't need to read it again here?

> +	if (pin) {
> +		irq = pci_bus0_irq_routing[PCI_SLOT(dev->devfn)][pin - 1];
> +		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
>  	}
> +	pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &line);
> +	return irq;
> +}
> +
> +int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
> +{
> +	bridge->swizzle_irq = NULL;
> +	bridge->map_irq = pcibios_map_irq;
> +	return 0;
>  }
>  
>  void pcibios_enable_irq(struct pci_dev *dev)
> diff --git a/arch/frv/mb93090-mb00/pci-vdk.c b/arch/frv/mb93090-mb00/pci-vdk.c
> index efa5d65..86657a7 100644
> --- a/arch/frv/mb93090-mb00/pci-vdk.c
> +++ b/arch/frv/mb93090-mb00/pci-vdk.c
> @@ -386,7 +386,6 @@ int __init pcibios_init(void)
>  	pci_scan_root_bus(NULL, 0, pci_root_ops, NULL, &resources);
>  
>  	pcibios_irq_init();
> -	pcibios_fixup_irqs();
>  	pcibios_resource_survey();
>  
>  	return 0;
> -- 
> 2.1.0
>