PCI: designware: Simplify dw_pcie_cfg_read/write() interfaces

Callers of dw_pcie_cfg_read() and dw_pcie_cfg_write() previously had to
split the address into "addr" and "where".  The callees assumed "addr" was
32-bit aligned (with zeros in the low two bits) and they used only the low
two bits of "where".

Accept the entire address in "addr" and drop the now-redundant "where"
argument.  As an example, this replaces this:

  int dw_pcie_cfg_read(void __iomem *addr, int where, int size, u32 *val)
    *val = readb(addr + (where & 1));

with this:

  int dw_pcie_cfg_read(void __iomem *addr, int size, u32 *val)
    *val = readb(addr):

[bhelgaas: changelog, split access size change to separate patch]
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/host/pci-exynos.c

@@ -454,7 +454,7 @@ static int exynos_pcie_rd_own_conf(struct pcie_port *pp, int where, int size,
 	int ret;
 
 	exynos_pcie_sideband_dbi_r_mode(pp, true);
-	ret = dw_pcie_cfg_read(pp->dbi_base + (where & ~0x3), where, size, val);
+	ret = dw_pcie_cfg_read(pp->dbi_base + where, size, val);
 	exynos_pcie_sideband_dbi_r_mode(pp, false);
 	return ret;
 }
@@ -465,8 +465,7 @@ static int exynos_pcie_wr_own_conf(struct pcie_port *pp, int where, int size,
 	int ret;
 
 	exynos_pcie_sideband_dbi_w_mode(pp, true);
-	ret = dw_pcie_cfg_write(pp->dbi_base + (where & ~0x3),
-			where, size, val);
+	ret = dw_pcie_cfg_write(pp->dbi_base + where, size, val);
 	exynos_pcie_sideband_dbi_w_mode(pp, false);
 	return ret;
 }

drivers/pci/host/pci-keystone-dw.c

@@ -398,7 +398,7 @@ int ks_dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 
 	addr = ks_pcie_cfg_setup(ks_pcie, bus_num, devfn);
 
-	return dw_pcie_cfg_read(addr + (where & ~0x3), where, size, val);
+	return dw_pcie_cfg_read(addr + where, size, val);
 }
 
 int ks_dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
@@ -410,7 +410,7 @@ int ks_dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 
 	addr = ks_pcie_cfg_setup(ks_pcie, bus_num, devfn);
 
-	return dw_pcie_cfg_write(addr + (where & ~0x3), where, size, val);
+	return dw_pcie_cfg_write(addr + where, size, val);
 }
 
 /**

drivers/pci/host/pcie-designware.c

@@ -80,14 +80,14 @@ static inline struct pcie_port *sys_to_pcie(struct pci_sys_data *sys)
 	return sys->private_data;
 }
 
-int dw_pcie_cfg_read(void __iomem *addr, int where, int size, u32 *val)
+int dw_pcie_cfg_read(void __iomem *addr, int size, u32 *val)
 {
 	if (size == 4)
 		*val = readl(addr);
 	else if (size == 2)
-		*val = readw(addr + (where & 2));
+		*val = readw(addr);
 	else if (size == 1)
-		*val = readb(addr + (where & 1));
+		*val = readb(addr);
 	else {
 		*val = 0;
 		return PCIBIOS_BAD_REGISTER_NUMBER;
@@ -96,14 +96,14 @@ int dw_pcie_cfg_read(void __iomem *addr, int where, int size, u32 *val)
 	return PCIBIOS_SUCCESSFUL;
 }
 
-int dw_pcie_cfg_write(void __iomem *addr, int where, int size, u32 val)
+int dw_pcie_cfg_write(void __iomem *addr, int size, u32 val)
 {
 	if (size == 4)
 		writel(val, addr);
 	else if (size == 2)
-		writew(val, addr + (where & 2));
+		writew(val, addr);
 	else if (size == 1)
-		writeb(val, addr + (where & 3));
+		writeb(val, addr);
 	else
 		return PCIBIOS_BAD_REGISTER_NUMBER;
 
@@ -134,8 +134,7 @@ static int dw_pcie_rd_own_conf(struct pcie_port *pp, int where, int size,
 	if (pp->ops->rd_own_conf)
 		ret = pp->ops->rd_own_conf(pp, where, size, val);
 	else
-		ret = dw_pcie_cfg_read(pp->dbi_base + (where & ~0x3), where,
-				size, val);
+		ret = dw_pcie_cfg_read(pp->dbi_base + where, size, val);
 
 	return ret;
 }
@@ -148,8 +147,7 @@ static int dw_pcie_wr_own_conf(struct pcie_port *pp, int where, int size,
 	if (pp->ops->wr_own_conf)
 		ret = pp->ops->wr_own_conf(pp, where, size, val);
 	else
-		ret = dw_pcie_cfg_write(pp->dbi_base + (where & ~0x3), where,
-				size, val);
+		ret = dw_pcie_cfg_write(pp->dbi_base + where, size, val);
 
 	return ret;
 }
@@ -585,13 +583,12 @@ static int dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 		u32 devfn, int where, int size, u32 *val)
 {
 	int ret, type;
-	u32 address, busdev, cfg_size;
+	u32 busdev, cfg_size;
 	u64 cpu_addr;
 	void __iomem *va_cfg_base;
 
 	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
 		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
-	address = where & ~0x3;
 
 	if (bus->parent->number == pp->root_bus_nr) {
 		type = PCIE_ATU_TYPE_CFG0;
@@ -608,7 +605,7 @@ static int dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 	dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
 				  type, cpu_addr,
 				  busdev, cfg_size);
-	ret = dw_pcie_cfg_read(va_cfg_base + address, where, size, val);
+	ret = dw_pcie_cfg_read(va_cfg_base + where, size, val);
 	dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
 				  PCIE_ATU_TYPE_IO, pp->io_mod_base,
 				  pp->io_bus_addr, pp->io_size);
@@ -620,13 +617,12 @@ static int dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 		u32 devfn, int where, int size, u32 val)
 {
 	int ret, type;
-	u32 address, busdev, cfg_size;
+	u32 busdev, cfg_size;
 	u64 cpu_addr;
 	void __iomem *va_cfg_base;
 
 	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
 		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
-	address = where & ~0x3;
 
 	if (bus->parent->number == pp->root_bus_nr) {
 		type = PCIE_ATU_TYPE_CFG0;
@@ -643,7 +639,7 @@ static int dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 	dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
 				  type, cpu_addr,
 				  busdev, cfg_size);
-	ret = dw_pcie_cfg_write(va_cfg_base + address, where, size, val);
+	ret = dw_pcie_cfg_write(va_cfg_base + where, size, val);
 	dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
 				  PCIE_ATU_TYPE_IO, pp->io_mod_base,
 				  pp->io_bus_addr, pp->io_size);

drivers/pci/host/pcie-designware.h

@@ -76,8 +76,8 @@ struct pcie_host_ops {
 	int (*msi_host_init)(struct pcie_port *pp, struct msi_controller *chip);
 };
 
-int dw_pcie_cfg_read(void __iomem *addr, int where, int size, u32 *val);
-int dw_pcie_cfg_write(void __iomem *addr, int where, int size, u32 val);
+int dw_pcie_cfg_read(void __iomem *addr, int size, u32 *val);
+int dw_pcie_cfg_write(void __iomem *addr, int size, u32 val);
 irqreturn_t dw_handle_msi_irq(struct pcie_port *pp);
 void dw_pcie_msi_init(struct pcie_port *pp);
 int dw_pcie_link_up(struct pcie_port *pp);

drivers/pci/host/pcie-spear13xx.c

@@ -163,14 +163,12 @@ static int spear13xx_pcie_establish_link(struct pcie_port *pp)
 	 * default value in capability register is 512 bytes. So force
 	 * it to 128 here.
 	 */
-	dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL,
-				0, 2, &val);
+	dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, &val);
 	val &= ~PCI_EXP_DEVCTL_READRQ;
-	dw_pcie_cfg_write(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL,
-				0, 2, val);
+	dw_pcie_cfg_write(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, val);
 
-	dw_pcie_cfg_write(pp->dbi_base + PCI_VENDOR_ID, 0, 2, 0x104A);
-	dw_pcie_cfg_write(pp->dbi_base + PCI_VENDOR_ID, 2, 2, 0xCD80);
+	dw_pcie_cfg_write(pp->dbi_base + PCI_VENDOR_ID, 2, 0x104A);
+	dw_pcie_cfg_write(pp->dbi_base + PCI_DEVICE_ID, 2, 0xCD80);
 
 	/*
 	 * if is_gen1 is set then handle it, so that some buggy card
@@ -178,21 +176,21 @@ static int spear13xx_pcie_establish_link(struct pcie_port *pp)
 	 */
 	if (spear13xx_pcie->is_gen1) {
 		dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_LNKCAP,
-					0, 4, &val);
+					4, &val);
 		if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) {
 			val &= ~((u32)PCI_EXP_LNKCAP_SLS);
 			val |= PCI_EXP_LNKCAP_SLS_2_5GB;
 			dw_pcie_cfg_write(pp->dbi_base + exp_cap_off +
-						PCI_EXP_LNKCAP, 0, 4, val);
+				PCI_EXP_LNKCAP, 4, val);
 		}
 
 		dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_LNKCTL2,
-					0, 2, &val);
+					2, &val);
 		if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) {
 			val &= ~((u32)PCI_EXP_LNKCAP_SLS);
 			val |= PCI_EXP_LNKCAP_SLS_2_5GB;
 			dw_pcie_cfg_write(pp->dbi_base + exp_cap_off +
-						PCI_EXP_LNKCTL2, 0, 2, val);
+					PCI_EXP_LNKCTL2, 2, val);
 		}
 	}