PCI: dwc/meson: Rework PCI config and DW port logic register accesses

The meson 'elbi' registers are just the Designware 'dbi' space and all
the registers accessed are either standard PCI config space or DWC port
logic registers. Convert the accesses to use the common defines and
register accessors.

Link: https://lore.kernel.org/r/20200821035420.380495-28-robh@kernel.orgSigned-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Yue Wang <yue.wang@Amlogic.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: linux-amlogic@lists.infradead.org

drivers/pci/controller/dwc/pci-meson.c

@@ -22,11 +22,7 @@
 
 #define to_meson_pcie(x) dev_get_drvdata((x)->dev)
 
-#define PCIE_CAP_OFFSET			0x70
-#define PCIE_DEV_CTRL_DEV_STUS		(PCIE_CAP_OFFSET + 0x08)
-#define PCIE_CAP_MAX_PAYLOAD_MASK	GENMASK(7, 5)
 #define PCIE_CAP_MAX_PAYLOAD_SIZE(x)	((x) << 5)
-#define PCIE_CAP_MAX_READ_REQ_MASK	GENMASK(14, 12)
 #define PCIE_CAP_MAX_READ_REQ_SIZE(x)	((x) << 12)
 
 /* PCIe specific config registers */
@@ -56,11 +52,6 @@ enum pcie_data_rate {
 	PCIE_GEN4
 };
 
-struct meson_pcie_mem_res {
-	void __iomem *elbi_base;
-	void __iomem *cfg_base;
-};
-
 struct meson_pcie_clk_res {
 	struct clk *clk;
 	struct clk *port_clk;
@@ -74,7 +65,7 @@ struct meson_pcie_rc_reset {
 
 struct meson_pcie {
 	struct dw_pcie pci;
-	struct meson_pcie_mem_res mem_res;
+	void __iomem *cfg_base;
 	struct meson_pcie_clk_res clk_res;
 	struct meson_pcie_rc_reset mrst;
 	struct gpio_desc *reset_gpio;
@@ -113,28 +104,18 @@ static int meson_pcie_get_resets(struct meson_pcie *mp)
 	return 0;
 }
 
-static void __iomem *meson_pcie_get_mem(struct platform_device *pdev,
-					struct meson_pcie *mp,
-					const char *id)
-{
-	struct device *dev = mp->pci.dev;
-	struct resource *res;
-
-	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, id);
-
-	return devm_ioremap_resource(dev, res);
-}
-
 static int meson_pcie_get_mems(struct platform_device *pdev,
 			       struct meson_pcie *mp)
 {
-	mp->mem_res.elbi_base = meson_pcie_get_mem(pdev, mp, "elbi");
-	if (IS_ERR(mp->mem_res.elbi_base))
-		return PTR_ERR(mp->mem_res.elbi_base);
+	struct dw_pcie *pci = &mp->pci;
+
+	pci->dbi_base = devm_platform_ioremap_resource_byname(pdev, "elbi");
+	if (IS_ERR(pci->dbi_base))
+		return PTR_ERR(pci->dbi_base);
 
-	mp->mem_res.cfg_base = meson_pcie_get_mem(pdev, mp, "cfg");
-	if (IS_ERR(mp->mem_res.cfg_base))
-		return PTR_ERR(mp->mem_res.cfg_base);
+	mp->cfg_base = devm_platform_ioremap_resource_byname(pdev, "cfg");
+	if (IS_ERR(mp->cfg_base))
+		return PTR_ERR(mp->cfg_base);
 
 	return 0;
 }
@@ -232,24 +213,14 @@ static int meson_pcie_probe_clocks(struct meson_pcie *mp)
 	return 0;
 }
 
-static inline void meson_elb_writel(struct meson_pcie *mp, u32 val, u32 reg)
-{
-	writel(val, mp->mem_res.elbi_base + reg);
-}
-
-static inline u32 meson_elb_readl(struct meson_pcie *mp, u32 reg)
-{
-	return readl(mp->mem_res.elbi_base + reg);
-}
-
 static inline u32 meson_cfg_readl(struct meson_pcie *mp, u32 reg)
 {
-	return readl(mp->mem_res.cfg_base + reg);
+	return readl(mp->cfg_base + reg);
 }
 
 static inline void meson_cfg_writel(struct meson_pcie *mp, u32 val, u32 reg)
 {
-	writel(val, mp->mem_res.cfg_base + reg);
+	writel(val, mp->cfg_base + reg);
 }
 
 static void meson_pcie_assert_reset(struct meson_pcie *mp)
@@ -287,30 +258,34 @@ static int meson_size_to_payload(struct meson_pcie *mp, int size)
 
 static void meson_set_max_payload(struct meson_pcie *mp, int size)
 {
+	struct dw_pcie *pci = &mp->pci;
 	u32 val;
+	u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
 	int max_payload_size = meson_size_to_payload(mp, size);
 
-	val = meson_elb_readl(mp, PCIE_DEV_CTRL_DEV_STUS);
-	val &= ~PCIE_CAP_MAX_PAYLOAD_MASK;
-	meson_elb_writel(mp, val, PCIE_DEV_CTRL_DEV_STUS);
+	val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_DEVCTL);
+	val &= ~PCI_EXP_DEVCTL_PAYLOAD;
+	dw_pcie_writel_dbi(pci, offset + PCI_EXP_DEVCTL, val);
 
-	val = meson_elb_readl(mp, PCIE_DEV_CTRL_DEV_STUS);
+	val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_DEVCTL);
 	val |= PCIE_CAP_MAX_PAYLOAD_SIZE(max_payload_size);
-	meson_elb_writel(mp, val, PCIE_DEV_CTRL_DEV_STUS);
+	dw_pcie_writel_dbi(pci, offset + PCI_EXP_DEVCTL, val);
 }
 
 static void meson_set_max_rd_req_size(struct meson_pcie *mp, int size)
 {
+	struct dw_pcie *pci = &mp->pci;
 	u32 val;
+	u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
 	int max_rd_req_size = meson_size_to_payload(mp, size);
 
-	val = meson_elb_readl(mp, PCIE_DEV_CTRL_DEV_STUS);
-	val &= ~PCIE_CAP_MAX_READ_REQ_MASK;
-	meson_elb_writel(mp, val, PCIE_DEV_CTRL_DEV_STUS);
+	val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_DEVCTL);
+	val &= ~PCI_EXP_DEVCTL_READRQ;
+	dw_pcie_writel_dbi(pci, offset + PCI_EXP_DEVCTL, val);
 
-	val = meson_elb_readl(mp, PCIE_DEV_CTRL_DEV_STUS);
+	val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_DEVCTL);
 	val |= PCIE_CAP_MAX_READ_REQ_SIZE(max_rd_req_size);
-	meson_elb_writel(mp, val, PCIE_DEV_CTRL_DEV_STUS);
+	dw_pcie_writel_dbi(pci, offset + PCI_EXP_DEVCTL, val);
 }
 
 static int meson_pcie_establish_link(struct meson_pcie *mp)
@@ -436,7 +411,6 @@ static int meson_add_pcie_port(struct meson_pcie *mp,
 	}
 
 	pp->ops = &meson_pcie_host_ops;
-	pci->dbi_base = mp->mem_res.elbi_base;
 
 	ret = dw_pcie_host_init(pp);
 	if (ret) {