Re: [RFC PATCH v1 14/18] powerpc/PCI: get rid of device resource fixups

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

On Mon, 2012-01-30 at 09:58 -0700, Bjorn Helgaas wrote:
> Tell the PCI core about host bridge address translation so it can take
> care of bus-to-resource conversion for us.
> 
> N.B. powerpc used a 32-bit mask when converting IO addresses.  If we
> figure out the right offset, I think simple addition should do the
> same thing, but I might not have it exactly right yet.

Wow that's going to be a big change :-) A quick look... seems like you
do a per-resource offset right ? I will need that (was about to change
powerpc) as we have hardware that provides us with two different windows
to MMIO space with different offsets unfortunately.

One thing I also want to generalize is the whole "REASSIGN_ALL_RSRC"
flag, ie, avoid reading & printing all those resources we know we are
just going to kill off.

I'll try to test your stuff asap (I'm doing 3 things at once right now
so it might take a few days unless I find somebody to look at it).

Cheers,
Ben.

> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> ---
>  arch/powerpc/include/asm/pci.h   |    8 ----
>  arch/powerpc/kernel/pci-common.c |   79 ++------------------------------------
>  2 files changed, 6 insertions(+), 81 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/pci.h b/arch/powerpc/include/asm/pci.h
> index f54b3d2..839178b 100644
> --- a/arch/powerpc/include/asm/pci.h
> +++ b/arch/powerpc/include/asm/pci.h
> @@ -154,13 +154,7 @@ extern int pci_mmap_legacy_page_range(struct pci_bus *bus,
>  
>  #endif /* CONFIG_PPC64 */
>  
> -extern void pcibios_resource_to_bus(struct pci_dev *dev,
> -			struct pci_bus_region *region,
> -			struct resource *res);
> -
> -extern void pcibios_bus_to_resource(struct pci_dev *dev,
> -			struct resource *res,
> -			struct pci_bus_region *region);
> +#define ARCH_HAS_GENERIC_PCI_OFFSETS
>  
>  extern void pcibios_claim_one_bus(struct pci_bus *b);
>  
> diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
> index cce98d7..f0084c9 100644
> --- a/arch/powerpc/kernel/pci-common.c
> +++ b/arch/powerpc/kernel/pci-common.c
> @@ -849,60 +849,6 @@ int pci_proc_domain(struct pci_bus *bus)
>  	return 1;
>  }
>  
> -void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
> -			     struct resource *res)
> -{
> -	resource_size_t offset = 0, mask = (resource_size_t)-1;
> -	struct pci_controller *hose = pci_bus_to_host(dev->bus);
> -
> -	if (!hose)
> -		return;
> -	if (res->flags & IORESOURCE_IO) {
> -		offset = (unsigned long)hose->io_base_virt - _IO_BASE;
> -		mask = 0xffffffffu;
> -	} else if (res->flags & IORESOURCE_MEM)
> -		offset = hose->pci_mem_offset;
> -
> -	region->start = (res->start - offset) & mask;
> -	region->end = (res->end - offset) & mask;
> -}
> -EXPORT_SYMBOL(pcibios_resource_to_bus);
> -
> -void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
> -			     struct pci_bus_region *region)
> -{
> -	resource_size_t offset = 0, mask = (resource_size_t)-1;
> -	struct pci_controller *hose = pci_bus_to_host(dev->bus);
> -
> -	if (!hose)
> -		return;
> -	if (res->flags & IORESOURCE_IO) {
> -		offset = (unsigned long)hose->io_base_virt - _IO_BASE;
> -		mask = 0xffffffffu;
> -	} else if (res->flags & IORESOURCE_MEM)
> -		offset = hose->pci_mem_offset;
> -	res->start = (region->start + offset) & mask;
> -	res->end = (region->end + offset) & mask;
> -}
> -EXPORT_SYMBOL(pcibios_bus_to_resource);
> -
> -/* Fixup a bus resource into a linux resource */
> -static void __devinit fixup_resource(struct resource *res, struct pci_dev *dev)
> -{
> -	struct pci_controller *hose = pci_bus_to_host(dev->bus);
> -	resource_size_t offset = 0, mask = (resource_size_t)-1;
> -
> -	if (res->flags & IORESOURCE_IO) {
> -		offset = (unsigned long)hose->io_base_virt - _IO_BASE;
> -		mask = 0xffffffffu;
> -	} else if (res->flags & IORESOURCE_MEM)
> -		offset = hose->pci_mem_offset;
> -
> -	res->start = (res->start + offset) & mask;
> -	res->end = (res->end + offset) & mask;
> -}
> -
> -
>  /* This header fixup will do the resource fixup for all devices as they are
>   * probed, but not for bridge ranges
>   */
> @@ -942,18 +888,11 @@ static void __devinit pcibios_fixup_resources(struct pci_dev *dev)
>  			continue;
>  		}
>  
> -		pr_debug("PCI:%s Resource %d %016llx-%016llx [%x] fixup...\n",
> +		pr_debug("PCI:%s Resource %d %016llx-%016llx [%x]\n",
>  			 pci_name(dev), i,
>  			 (unsigned long long)res->start,\
>  			 (unsigned long long)res->end,
>  			 (unsigned int)res->flags);
> -
> -		fixup_resource(res, dev);
> -
> -		pr_debug("PCI:%s            %016llx-%016llx\n",
> -			 pci_name(dev),
> -			 (unsigned long long)res->start,
> -			 (unsigned long long)res->end);
>  	}
>  
>  	/* Call machine specific resource fixup */
> @@ -1055,27 +994,18 @@ static void __devinit pcibios_fixup_bridge(struct pci_bus *bus)
>  			continue;
>  		}
>  
> -		pr_debug("PCI:%s Bus rsrc %d %016llx-%016llx [%x] fixup...\n",
> +		pr_debug("PCI:%s Bus rsrc %d %016llx-%016llx [%x]\n",
>  			 pci_name(dev), i,
>  			 (unsigned long long)res->start,\
>  			 (unsigned long long)res->end,
>  			 (unsigned int)res->flags);
>  
> -		/* Perform fixup */
> -		fixup_resource(res, dev);
> -
>  		/* Try to detect uninitialized P2P bridge resources,
>  		 * and clear them out so they get re-assigned later
>  		 */
>  		if (pcibios_uninitialized_bridge_resource(bus, res)) {
>  			res->flags = 0;
>  			pr_debug("PCI:%s            (unassigned)\n", pci_name(dev));
> -		} else {
> -
> -			pr_debug("PCI:%s            %016llx-%016llx\n",
> -				 pci_name(dev),
> -				 (unsigned long long)res->start,
> -				 (unsigned long long)res->end);
>  		}
>  	}
>  }
> @@ -1589,7 +1519,8 @@ static void __devinit pcibios_setup_phb_resources(struct pci_controller *hose, s
>  		 (unsigned long long)res->start,
>  		 (unsigned long long)res->end,
>  		 (unsigned long)res->flags);
> -	pci_add_resource(resources, res);
> +	pci_add_resource_offset(resources, res,
> +			(resource_size_t) hose->io_base_virt - _IO_BASE);
>  
>  	/* Hookup PHB Memory resources */
>  	for (i = 0; i < 3; ++i) {
> @@ -1612,7 +1543,7 @@ static void __devinit pcibios_setup_phb_resources(struct pci_controller *hose, s
>  			 (unsigned long long)res->start,
>  			 (unsigned long long)res->end,
>  			 (unsigned long)res->flags);
> -		pci_add_resource(resources, res);
> +		pci_add_resource_offset(resources, res, hose->pci_mem_offset);
>  	}
>  
>  	pr_debug("PCI: PHB MEM offset     = %016llx\n",