On Thu, Dec 01, 2016 at 06:52:23PM -0800, Duc Dang wrote:
> On Thu, Dec 1, 2016 at 10:33 AM, Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
> I made similar changes in v4 patch. The ECAM quirk will be built when
> ACPI and PCI_QUIRKS are enabled.
>
> When building for DT only, the ECAM quirk won't be compiled.
Perfect.
> >> #define XGENE_PCIE_IP_VER_UNKN 0
> >> #define XGENE_PCIE_IP_VER_1 1
> >> +#define XGENE_PCIE_IP_VER_2 2
> >
> > This isn't used anywhere, which makes me wonder whether it's worth
> > keeping it.
>
> V2 controller will use this XGENE_PCIE_IP_VER_2 (port->version =
> XGENE_PCIE_IP_VER_2). This will be used to indicate that the
> controller is V2, and to enable configuration request retry status
> feature (by not disable it like V1 controller).
OK, I see. You don't actually need XGENE_PCIE_IP_VER_2, you just need
port->version to be something other than XGENE_PCIE_IP_VER_1. So this
is fine as it is.
> >> static void __iomem *xgene_pcie_get_cfg_base(struct pci_bus *bus)
> >> {
> >> - struct xgene_pcie_port *port = bus->sysdata;
> >> + struct pci_config_window *cfg;
> >> + struct xgene_pcie_port *port;
> >> +
> >> + if (acpi_disabled)
> >> + port = bus->sysdata;
> >> + else {
> >> + cfg = bus->sysdata;
> >> + port = cfg->priv;
> >> + }
> >
> > I would really, really like to figure out a way to get rid of these
> > "if (acpi_disabled)" checks sprinkled through here. Is there any way
> > we can set up bus->sysdata to be the same, regardless of whether we're
> > using this as a platform driver or an ACPI quirk?
>
> Right now, I created a inline function to extract xgene_pcie_port from
> pci_bus. In order to get rid of acpi_disabled, I will need to make
> sysdata in DT case also point to pci_config_window structure, which
> means I will need to convert and test the DT driver to use ecam ops.
> It is a separate patch itself. So I think I should do it at later time
> (after this ECAM quirk patch). I hope you are ok with this.
OK. I did the simple-minded version of leaving the DT ops the same
but making sysdata point to a dummy pci_config_window. Your proposal
of using ECAM for DT would be much better.
It's interesting that you actually already use the same accessors
except that DT uses the 32-bit pci_generic_config_write32() and ACPI
uses the regular pci_generic_config_write(). I guess that means the
hardware actually *does* support sub-32 bit writes?
> I need to define the function (xgene_get_csr_resource()) inside
> pci-xgene.c to duplicate the code of acpi_get_rc_addr. The reason is
> X-Gene firmware does not have a dedicate PNP0C02 node to declare the
> resource, and if I use acpi_get_rc_resources() with "PNP0A08", I got
> error due to acpi_bus_get_device() returns error.
Looks good.
> > All these init functions are almost identical. Can we factor this out
> > by having wrappers that do nothing more than pass in the table and
> > version, and put the kzalloc and ioremap in a shared back-end?
>
> I refactor-ed these .init functions. And as a result, there are only 2
> ecam ops left: xgene_v1_pcie_ecam_ops and xgene_v2_pcie_ecam_ops.
Looks good.
Bjorn
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