Re: [PATCH 2/2] PCI: generic: Add set_msi_parent callback

[Will Deacon <will.deacon@arm.com>]

Hi Suravee,

On Mon, Nov 10, 2014 at 07:24:40PM +0000, suravee.suthikulpanit@amd.com wrote:
> From: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
> 
> This patch implement set_msi_parent callback for PCI generic host controller.
> 
> Cc: Bjorn Helgass <bhelgaas@google.com>
> Cc: Liviu Dudau <liviu.dudau@arm.com>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
> ---
>  drivers/pci/host/pci-host-generic.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c
> index 036ab1b..f9bb97a 100644
> --- a/drivers/pci/host/pci-host-generic.c
> +++ b/drivers/pci/host/pci-host-generic.c
> @@ -42,6 +42,7 @@ struct gen_pci {
>  	struct pci_host_bridge			host;
>  	struct gen_pci_cfg_windows		cfg;
>  	struct list_head			resources;
> +	struct msi_chip				*mchip;
>  };
>  
>  #ifdef CONFIG_ARM
> @@ -128,9 +129,19 @@ static int gen_pci_config_write(struct pci_bus *bus, unsigned int devfn,
>  	return PCIBIOS_SUCCESSFUL;
>  }
>  
> +static int gen_pci_set_msi_parent(struct pci_bus *bus)
> +{
> +	struct gen_pci *pci = bus_to_gen_pci(bus);
> +
> +	bus->msi = pci->mchip;
> +
> +	return PCIBIOS_SUCCESSFUL;
> +}

I don't think this makes much sense a host controller callback. Why can't
bus->msi be set in generic code?

>  static struct pci_ops gen_pci_ops = {
>  	.read	= gen_pci_config_read,
>  	.write	= gen_pci_config_write,
> +	.set_msi_parent = gen_pci_set_msi_parent,
>  };
>  
>  static const struct of_device_id gen_pci_of_match[] = {
> @@ -313,6 +324,9 @@ static int gen_pci_probe(struct platform_device *pdev)
>  		return err;
>  	}
>  
> +	pci->mchip = of_pci_find_msi_chip_by_node(of_parse_phandle(np,
> +						  "msi-parent", 0));

This bit should be in the generic of_pci.c code and not duplicated for
each host controller.

Will