On Mar 16, 2015, at 9:20 AM, Gabriel FERNANDEZ <gabriel.fernandez@xxxxxx> wrote: > ST sti SoCs PCIe IPs are built around DesignWare IP Core. > But in these SoCs PCIe IP doesn't support IO. > > This patch adds the possibility to disable it through > a DT property, by creating an empty IO window and by > removing PCI_COMMAND_IO from the setup register. > > Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxx> > Signed-off-by: Gabriel Fernandez <gabriel.fernandez@xxxxxxxxxx> > --- > .../devicetree/bindings/pci/designware-pcie.txt | 2 ++ > drivers/pci/host/pcie-designware.c | 24 ++++++++++++++++++++-- > drivers/pci/host/pcie-designware.h | 1 + > 3 files changed, 25 insertions(+), 2 deletions(-) Why not just update the code such that if the ranges doesn’t have an IO space rather than introducing a new DT property? - k > > diff --git a/Documentation/devicetree/bindings/pci/designware-pcie.txt b/Documentation/devicetree/bindings/pci/designware-pcie.txt > index 9f4faa8..40544d4 100644 > --- a/Documentation/devicetree/bindings/pci/designware-pcie.txt > +++ b/Documentation/devicetree/bindings/pci/designware-pcie.txt > @@ -26,3 +26,5 @@ Optional properties: > - bus-range: PCI bus numbers covered (it is recommended for new devicetrees to > specify this property, to keep backwards compatibility a range of 0x00-0xff > is assumed if not present) > +- disable_io_support: set this property for PCIe host controller without IO > + port access > diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c > index 1f4ea6f..f9d70f5 100644 > --- a/drivers/pci/host/pcie-designware.c > +++ b/drivers/pci/host/pcie-designware.c > @@ -471,6 +471,9 @@ int __init dw_pcie_host_init(struct pcie_port *pp) > return -EINVAL; > } > > + pp->disable_io_support = of_property_read_bool(np, > + "disable_io_support"); > + > if (IS_ENABLED(CONFIG_PCI_MSI)) { > if (!pp->ops->msi_host_init) { > pp->irq_domain = irq_domain_add_linear(pp->dev->of_node, > @@ -704,6 +707,7 @@ static struct pci_ops dw_pcie_ops = { > static int dw_pcie_setup(int nr, struct pci_sys_data *sys) > { > struct pcie_port *pp; > + struct resource *res; > > pp = sys_to_pcie(sys); > > @@ -719,6 +723,18 @@ static int dw_pcie_setup(int nr, struct pci_sys_data *sys) > pci_add_resource_offset(&sys->resources, &pp->mem, sys->mem_offset); > pci_add_resource(&sys->resources, &pp->busn); > > + if (pp->disable_io_support) { > + /* This PCIe controller does not support IO, set an empty one */ > + res = devm_kzalloc(pp->dev, sizeof(*res), GFP_KERNEL); > + if (res) { > + res->start = 0; > + res->end = 0; > + res->name = "PCIe empty IO space"; > + res->flags = IORESOURCE_IO; > + pci_add_resource(&sys->resources, res); Do we really need an empty resource? What happens if we just dont have one? > + } > + } > + > return 1; > } > > @@ -822,8 +838,12 @@ void dw_pcie_setup_rc(struct pcie_port *pp) > /* setup command register */ > dw_pcie_readl_rc(pp, PCI_COMMAND, &val); > val &= 0xffff0000; > - val |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | > - PCI_COMMAND_MASTER | PCI_COMMAND_SERR; > + > + if (!pp->disable_io_support) > + val |= PCI_COMMAND_IO; > + > + val |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_SERR; > + > dw_pcie_writel_rc(pp, val, PCI_COMMAND); > } > > diff --git a/drivers/pci/host/pcie-designware.h b/drivers/pci/host/pcie-designware.h > index d0bbd27..027045d 100644 > --- a/drivers/pci/host/pcie-designware.h > +++ b/drivers/pci/host/pcie-designware.h > @@ -52,6 +52,7 @@ struct pcie_port { > int msi_irq; > struct irq_domain *irq_domain; > unsigned long msi_data; > + bool disable_io_support; > DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS); > }; > > -- > 1.9.1 > -- Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html