On Wed, Jan 5, 2022 at 9:03 AM Pali Rohár <pali@xxxxxxxxxx> wrote:
>
> Split struct pci_ops between ops and child_ops. Member ops is used for
> accessing PCIe Root Ports via pci-bridge-emul.c driver and child_ops for
> accessing real PCIe cards.
>
> There is no need to mix these two struct pci_ops into one as PCI core code
> already provides separate callbacks via bridge->ops and bridge->child_ops.
I had similar patches including mvebu that I never got around to
sending out. I pushed the branch out now at least[1].
> Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
> ---
> drivers/pci/controller/pci-mvebu.c | 82 ++++++++++++++++--------------
> 1 file changed, 44 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
> index 9ea2f6a7c2b0..1e90ab888075 100644
> --- a/drivers/pci/controller/pci-mvebu.c
> +++ b/drivers/pci/controller/pci-mvebu.c
> @@ -294,11 +294,29 @@ static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port)
> mvebu_writel(port, mask, PCIE_MASK_OFF);
> }
>
> -static int mvebu_pcie_hw_rd_conf(struct mvebu_pcie_port *port,
> - struct pci_bus *bus,
> - u32 devfn, int where, int size, u32 *val)
> +static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
> + struct pci_bus *bus,
> + int devfn);
> +
> +static int mvebu_pcie_child_rd_conf(struct pci_bus *bus, u32 devfn, int where,
> + int size, u32 *val)
> {
> - void __iomem *conf_data = port->base + PCIE_CONF_DATA_OFF;
> + struct mvebu_pcie *pcie = bus->sysdata;
> + struct mvebu_pcie_port *port;
> + void __iomem *conf_data;
> +
> + port = mvebu_pcie_find_port(pcie, bus, devfn);
> + if (!port) {
> + *val = 0xffffffff;
> + return PCIBIOS_DEVICE_NOT_FOUND;
> + }
> +
> + if (!mvebu_pcie_link_up(port)) {
> + *val = 0xffffffff;
> + return PCIBIOS_DEVICE_NOT_FOUND;
> + }
> +
> + conf_data = port->base + PCIE_CONF_DATA_OFF;
>
> mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
> PCIE_CONF_ADDR_OFF);
> @@ -321,11 +339,21 @@ static int mvebu_pcie_hw_rd_conf(struct mvebu_pcie_port *port,
> return PCIBIOS_SUCCESSFUL;
> }
>
> -static int mvebu_pcie_hw_wr_conf(struct mvebu_pcie_port *port,
> - struct pci_bus *bus,
> - u32 devfn, int where, int size, u32 val)
> +static int mvebu_pcie_child_wr_conf(struct pci_bus *bus, u32 devfn,
> + int where, int size, u32 val)
> {
> - void __iomem *conf_data = port->base + PCIE_CONF_DATA_OFF;
> + struct mvebu_pcie *pcie = bus->sysdata;
> + struct mvebu_pcie_port *port;
> + void __iomem *conf_data;
> +
> + port = mvebu_pcie_find_port(pcie, bus, devfn);
> + if (!port)
> + return PCIBIOS_DEVICE_NOT_FOUND;
> +
> + if (!mvebu_pcie_link_up(port))
> + return PCIBIOS_DEVICE_NOT_FOUND;
> +
> + conf_data = port->base + PCIE_CONF_DATA_OFF;
The same code in read and write is a hint to use .map_bus().
>
> mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
> PCIE_CONF_ADDR_OFF);
> @@ -347,6 +375,11 @@ static int mvebu_pcie_hw_wr_conf(struct mvebu_pcie_port *port,
> return PCIBIOS_SUCCESSFUL;
> }
>
> +static struct pci_ops mvebu_pcie_child_ops = {
> + .read = mvebu_pcie_child_rd_conf,
> + .write = mvebu_pcie_child_wr_conf,
> +};
> +
> /*
> * Remove windows, starting from the largest ones to the smallest
> * ones.
> @@ -862,25 +895,12 @@ static int mvebu_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
> {
> struct mvebu_pcie *pcie = bus->sysdata;
> struct mvebu_pcie_port *port;
> - int ret;
>
> port = mvebu_pcie_find_port(pcie, bus, devfn);
> if (!port)
> return PCIBIOS_DEVICE_NOT_FOUND;
It would be nice to go from 'bus' to 'bridge' ptr directly, but I
still had this in my version. I guess a standard RP struct as part of
decoupling host bridges from RPs would solve this issue.
Rob
[1] https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git/log/?h=pci-child-bus-ops
