Re: [PATCH 2/3] PCI: ARM: add support for virtual PCI host controller

[Arnd Bergmann <arnd@arndb.de>]

On Monday 10 February 2014 10:34:50 Jason Gunthorpe wrote:

> I noticed this on mvebu as well..
> 
> 3.13 w/ mvebu driver:
> 
> e0001000-e0001fff : /mbus/pex@e0000000/pcie@1,0/fpga@0/fpga_sysmon@1000
> e0006000-e0006fff : /mbus/pex@e0000000/pcie@1,0/fpga@0/qdr2p@6000
> 
> 3.10 w/ old kirkwood driver:
> 
> e0000000-e7ffffff : PCIe 0 MEM
>   e0000000-e001ffff : 0000:00:01.0
>     e0001000-e0001fff : /mbus/pex@e0000000/pcie@1,0/fpga@0/fpga_sysmon@1000
>     e0006000-e0006fff : /mbus/pex@e0000000/pcie@1,0/fpga@0/qdr2p@6000
> 
> The latter is obviously correct and matches x86. I'm not sure where
> the new style host drivers are going wrong, even the resource that
> should be added by the PCI core itself for the BAR is missing..

I looked briefly at the code and found that mach-kirkwood/pcie.c does
both request_resource() and pci_add_resource_offset(), while
drivers/pci/host/pci-mvebu.c only does the latter. Does the patch
below restore the previous behavior?

Since the mvebu_pcie_setup() function seems very generic at this,
we should probably try to factor out that code into a common
helper, at least for arm64, but ideally shared with arm32
as well.

	Arnd

diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
index 13478ec..b55e9a6 100644
--- a/drivers/pci/host/pci-mvebu.c
+++ b/drivers/pci/host/pci-mvebu.c
@@ -680,9 +680,17 @@ static int mvebu_pcie_setup(int nr, struct pci_sys_data *sys)
 	struct mvebu_pcie *pcie = sys_to_pcie(sys);
 	int i;
 
-	if (resource_size(&pcie->realio) != 0)
+	if (request_resource(&iomem_resource, &pcie->mem))
+		return 0;
+
+	if (resource_size(&pcie->realio) != 0) {
+		if (request_resource(&ioport_resource, &pcie->realio)) {
+			release_resource(&pcie->mem);
+			return 0;
+		}
 		pci_add_resource_offset(&sys->resources, &pcie->realio,
 					sys->io_offset);
+	}
 	pci_add_resource_offset(&sys->resources, &pcie->mem, sys->mem_offset);
 	pci_add_resource(&sys->resources, &pcie->busn);