PCI: designware: Add config access-related pcie_host_ops for v3.65 hardware

DesignWare v3.65 hardware requires application space registers to be
configured to access the remote EP config space.

To support this, add rd_other_conf() and wr_other_conf() to pcie_host_ops.

[bhelgaas: changelog]
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Pratyush Anand <pratyush.anand@st.com>
Acked-by: Mohit Kumar <mohit.kumar@st.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: Grant Likely <grant.likely@linaro.org>
CC: Rob Herring <robh+dt@kernel.org>
CC: Richard Zhu <r65037@freescale.com>
CC: Kishon Vijay Abraham I <kishon@ti.com>
CC: Marek Vasut <marex@denx.de>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Pawel Moll <pawel.moll@arm.com>
CC: Mark Rutland <mark.rutland@arm.com>
CC: Ian Campbell <ijc+devicetree@hellion.org.uk>
CC: Kumar Gala <galak@codeaurora.org>
CC: Randy Dunlap <rdunlap@infradead.org>
CC: Grant Likely <grant.likely@linaro.org>

drivers/pci/host/pcie-designware.c

@@ -696,7 +696,11 @@ static int dw_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
 	}
 
 	if (bus->number != pp->root_bus_nr)
-		ret = dw_pcie_rd_other_conf(pp, bus, devfn,
+		if (pp->ops->rd_other_conf)
+			ret = pp->ops->rd_other_conf(pp, bus, devfn,
+						where, size, val);
+		else
+			ret = dw_pcie_rd_other_conf(pp, bus, devfn,
 						where, size, val);
 	else
 		ret = dw_pcie_rd_own_conf(pp, where, size, val);
@@ -719,7 +723,11 @@ static int dw_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	if (bus->number != pp->root_bus_nr)
-		ret = dw_pcie_wr_other_conf(pp, bus, devfn,
+		if (pp->ops->wr_other_conf)
+			ret = pp->ops->wr_other_conf(pp, bus, devfn,
+						where, size, val);
+		else
+			ret = dw_pcie_wr_other_conf(pp, bus, devfn,
 						where, size, val);
 	else
 		ret = dw_pcie_wr_own_conf(pp, where, size, val);

drivers/pci/host/pcie-designware.h

@@ -65,6 +65,10 @@ struct pcie_host_ops {
 			u32 val, void __iomem *dbi_base);
 	int (*rd_own_conf)(struct pcie_port *pp, int where, int size, u32 *val);
 	int (*wr_own_conf)(struct pcie_port *pp, int where, int size, u32 val);
+	int (*rd_other_conf)(struct pcie_port *pp, struct pci_bus *bus,
+			unsigned int devfn, int where, int size, u32 *val);
+	int (*wr_other_conf)(struct pcie_port *pp, struct pci_bus *bus,
+			unsigned int devfn, int where, int size, u32 val);
 	int (*link_up)(struct pcie_port *pp);
 	void (*host_init)(struct pcie_port *pp);
 };