Re: [PATCHv4 10/11] pci: mvebu: add support for MSI

[Bjorn Helgaas <bhelgaas@google.com>]

On Mon, Jul 1, 2013 at 7:42 AM, Thomas Petazzoni
<thomas.petazzoni@free-electrons.com> wrote:
> This commit adds support for Message Signaled Interrupts in the
> Marvell PCIe host controller. The work is very simple: it simply gets
> a reference to the msi_chip associated to the PCIe controller thanks
> to the msi-parent DT property, and stores this reference in the
> pci_bus structure. This is enough to let the Linux PCI core use the
> functions of msi_chip to setup and teardown MSIs.
>
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> Reviewed-by: Thierry Reding <thierry.reding@gmail.com>
> Acked-by: Bjorn Helgaas <bhelgaas@google.com>

I've already acked this, and I reaffirm that.  Please adjust the
subject line to capitalize "PCI" and the first word of the descriptive
sentence.

> ---
>  .../devicetree/bindings/pci/mvebu-pci.txt          |  3 +++
>  drivers/pci/host/pci-mvebu.c                       | 26 ++++++++++++++++++++++
>  2 files changed, 29 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/pci/mvebu-pci.txt b/Documentation/devicetree/bindings/pci/mvebu-pci.txt
> index f8d4058..77e0ffe 100644
> --- a/Documentation/devicetree/bindings/pci/mvebu-pci.txt
> +++ b/Documentation/devicetree/bindings/pci/mvebu-pci.txt
> @@ -12,6 +12,8 @@ Mandatory properties:
>  - device_type, set to "pci"
>  - ranges: ranges for the PCI memory and I/O regions, as well as the
>    MMIO registers to control the PCIe interfaces.
> +- msi-parent: Link to the hardware entity that serves as the Message
> +  Signaled Interrupt controller for this PCI controller.
>
>  In addition, the Device Tree node must have sub-nodes describing each
>  PCIe interface, having the following mandatory properties:
> @@ -46,6 +48,7 @@ pcie-controller {
>         #size-cells = <2>;
>
>         bus-range = <0x00 0xff>;
> +       msi-parent = <&mpic>;
>
>         ranges = <0x82000000 0 0xd0040000 0xd0040000 0 0x00002000   /* Port 0.0 registers */
>                   0x82000000 0 0xd0042000 0xd0042000 0 0x00002000   /* Port 2.0 registers */
> diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
> index 13a633b..396f578 100644
> --- a/drivers/pci/host/pci-mvebu.c
> +++ b/drivers/pci/host/pci-mvebu.c
> @@ -11,6 +11,7 @@
>  #include <linux/clk.h>
>  #include <linux/module.h>
>  #include <linux/mbus.h>
> +#include <linux/msi.h>
>  #include <linux/slab.h>
>  #include <linux/platform_device.h>
>  #include <linux/of_address.h>
> @@ -107,6 +108,7 @@ struct mvebu_pcie_port;
>  struct mvebu_pcie {
>         struct platform_device *pdev;
>         struct mvebu_pcie_port *ports;
> +       struct msi_chip *msi;
>         struct resource io;
>         struct resource realio;
>         struct resource mem;
> @@ -695,6 +697,12 @@ static struct pci_bus *mvebu_pcie_scan_bus(int nr, struct pci_sys_data *sys)
>         return bus;
>  }
>
> +void mvebu_pcie_add_bus(struct pci_bus *bus)
> +{
> +       struct mvebu_pcie *pcie = sys_to_pcie(bus->sysdata);
> +       bus->msi = pcie->msi;
> +}
> +
>  resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev,
>                                           const struct resource *res,
>                                           resource_size_t start,
> @@ -731,6 +739,7 @@ static void __init mvebu_pcie_enable(struct mvebu_pcie *pcie)
>         hw.map_irq        = mvebu_pcie_map_irq;
>         hw.ops            = &mvebu_pcie_ops;
>         hw.align_resource = mvebu_pcie_align_resource;
> +       hw.add_bus        = mvebu_pcie_add_bus;
>
>         pci_common_init(&hw);
>  }
> @@ -755,6 +764,21 @@ mvebu_pcie_map_registers(struct platform_device *pdev,
>         return devm_request_and_ioremap(&pdev->dev, &regs);
>  }
>
> +static void __init mvebu_pcie_msi_enable(struct mvebu_pcie *pcie)
> +{
> +       struct device_node *msi_node;
> +
> +       msi_node = of_parse_phandle(pcie->pdev->dev.of_node,
> +                                   "msi-parent", 0);
> +       if (!msi_node)
> +               return;
> +
> +       pcie->msi = of_find_msi_chip_by_node(msi_node);
> +
> +       if (pcie->msi)
> +               pcie->msi->dev = &pcie->pdev->dev;
> +}
> +
>  static int __init mvebu_pcie_probe(struct platform_device *pdev)
>  {
>         struct mvebu_pcie *pcie;
> @@ -879,6 +903,8 @@ static int __init mvebu_pcie_probe(struct platform_device *pdev)
>                 i++;
>         }
>
> +       mvebu_pcie_msi_enable(pcie);
> +
>         mvebu_pcie_enable(pcie);
>
>         return 0;
> --
> 1.8.1.2
>