Re: [PATCH v3 3/6] PCI: Add generic function to probe PCI host controllers

[Lorenzo Pieralisi]

On Wed, Jan 10, 2018 at 11:47:32PM +0100, Cyrille Pitchen wrote:
> This patchs moves generic source code from
> drivers/pci/host/pci-host-common.c into drivers/pci/probe.c.
> 
> Indeed the extracted lines of code were duplicated by many host
> controller drivers. Regrouping them into a generic function gives a
> change to properly share this code without introducing a useless
> dependency to PCI_HOST_COMMON, which selects PCI_ECAM when not needed by
> most host controller drivers.
> 
> We also add a missing call of pci_free_resource_list() from
> pci_host_common_probe() when probing fails, as done inside gen_pci_init()
I have to ask you to split this change into another patch.

First add the missing pci_free_resource_list() then add this patch.

Do you have time to respin quickly ? I would like to merge this
series for v4.16.

Thanks,
Lorenzo

> when this later function fails.
> 
> Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxxxxxxxxxxx>
> ---
>  drivers/pci/host/pci-host-common.c | 25 +++----------------------
>  drivers/pci/probe.c                | 33 +++++++++++++++++++++++++++++++++
>  include/linux/pci.h                |  1 +
>  3 files changed, 37 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/pci/host/pci-host-common.c b/drivers/pci/host/pci-host-common.c
> index a613ea310e76..df25b4a4edaf 100644
> --- a/drivers/pci/host/pci-host-common.c
> +++ b/drivers/pci/host/pci-host-common.c
> @@ -72,7 +72,6 @@ int pci_host_common_probe(struct platform_device *pdev,
>  	const char *type;
>  	struct device *dev = &pdev->dev;
>  	struct device_node *np = dev->of_node;
> -	struct pci_bus *bus, *child;
>  	struct pci_host_bridge *bridge;
>  	struct pci_config_window *cfg;
>  	struct list_head resources;
> @@ -107,29 +106,11 @@ int pci_host_common_probe(struct platform_device *pdev,
>  	bridge->map_irq = of_irq_parse_and_map_pci;
>  	bridge->swizzle_irq = pci_common_swizzle;
>  
> -	ret = pci_scan_root_bus_bridge(bridge);
> -	if (ret < 0) {
> -		dev_err(dev, "Scanning root bridge failed");
> +	ret = pci_host_probe(bridge);
> +	if (ret) {
> +		pci_free_resource_list(&resources);
>  		return ret;
>  	}
>  
> -	bus = bridge->bus;
> -
> -	/*
> -	 * We insert PCI resources into the iomem_resource and
> -	 * ioport_resource trees in either pci_bus_claim_resources()
> -	 * or pci_bus_assign_resources().
> -	 */
> -	if (pci_has_flag(PCI_PROBE_ONLY)) {
> -		pci_bus_claim_resources(bus);
> -	} else {
> -		pci_bus_size_bridges(bus);
> -		pci_bus_assign_resources(bus);
> -
> -		list_for_each_entry(child, &bus->children, node)
> -			pcie_bus_configure_settings(child);
> -	}
> -
> -	pci_bus_add_devices(bus);
>  	return 0;
>  }
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index 1360db508035..178328d06a32 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -2685,6 +2685,39 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
>  }
>  EXPORT_SYMBOL_GPL(pci_create_root_bus);
>  
> +int pci_host_probe(struct pci_host_bridge *bridge)
> +{
> +	struct pci_bus *bus, *child;
> +	int ret;
> +
> +	ret = pci_scan_root_bus_bridge(bridge);
> +	if (ret < 0) {
> +		dev_err(bridge->dev.parent, "Scanning root bridge failed");
> +		return ret;
> +	}
> +
> +	bus = bridge->bus;
> +
> +	/*
> +	 * We insert PCI resources into the iomem_resource and
> +	 * ioport_resource trees in either pci_bus_claim_resources()
> +	 * or pci_bus_assign_resources().
> +	 */
> +	if (pci_has_flag(PCI_PROBE_ONLY)) {
> +		pci_bus_claim_resources(bus);
> +	} else {
> +		pci_bus_size_bridges(bus);
> +		pci_bus_assign_resources(bus);
> +
> +		list_for_each_entry(child, &bus->children, node)
> +			pcie_bus_configure_settings(child);
> +	}
> +
> +	pci_bus_add_devices(bus);
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(pci_host_probe);
> +
>  int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
>  {
>  	struct resource *res = &b->busn_res;
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index a1b0672fd38a..0ca261fda900 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -879,6 +879,7 @@ struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops, void *sysdata);
>  struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
>  				    struct pci_ops *ops, void *sysdata,
>  				    struct list_head *resources);
> +int pci_host_probe(struct pci_host_bridge *bridge);
>  int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busmax);
>  int pci_bus_update_busn_res_end(struct pci_bus *b, int busmax);
>  void pci_bus_release_busn_res(struct pci_bus *b);
> -- 
> 2.11.0
>