pci: uniphier: Add UniPhier PCIe controller driver

Add PCIe driver for UniPhier SoCs. This PCIe controller is based on
Synopsys DesignWare Core IP.

This version doesn't apply common DW functions because supported
controller doesn't have unroll version of iATU.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 782179e..517cf95 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -340,4 +340,14 @@
 	  on Broadcom set-top-box (STB) SoCs.
 	  This driver currently supports only BCM2711 SoC and RC mode
 	  of the controller.
+
+config PCIE_UNIPHIER
+	bool "Socionext UniPhier PCIe driver"
+	depends on DM_PCI
+	depends on ARCH_UNIPHIER
+	select PHY_UNIPHIER_PCIE
+	help
+	  Say Y here if you want to enable PCIe controller support on
+	  UniPhier SoCs.
+
 endif
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 6568dc9..ec8ee9d 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -56,3 +56,4 @@
 obj-$(CONFIG_PCI_OCTEONTX) += pci_octeontx.o
 obj-$(CONFIG_PCIE_OCTEON) += pcie_octeon.o
 obj-$(CONFIG_PCIE_DW_SIFIVE) += pcie_dw_sifive.o
+obj-$(CONFIG_PCIE_UNIPHIER) += pcie_uniphier.o
diff --git a/drivers/pci/pcie_uniphier.c b/drivers/pci/pcie_uniphier.c
new file mode 100644
index 0000000..f2edea9
--- /dev/null
+++ b/drivers/pci/pcie_uniphier.c
@@ -0,0 +1,424 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * pcie_uniphier.c - Socionext UniPhier PCIe driver
+ * Copyright 2019-2021 Socionext, Inc.
+ */
+
+#include <clk.h>
+#include <common.h>
+#include <dm.h>
+#include <dm/device_compat.h>
+#include <generic-phy.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/compat.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <pci.h>
+#include <reset.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* DBI registers */
+#define PCIE_LINK_STATUS_REG		0x0080
+#define PCIE_LINK_STATUS_WIDTH_MASK	GENMASK(25, 20)
+#define PCIE_LINK_STATUS_SPEED_MASK	GENMASK(19, 16)
+
+#define PCIE_MISC_CONTROL_1_OFF		0x08BC
+#define PCIE_DBI_RO_WR_EN		BIT(0)
+
+/* DBI iATU registers */
+#define PCIE_ATU_VIEWPORT		0x0900
+#define PCIE_ATU_REGION_INBOUND		BIT(31)
+#define PCIE_ATU_REGION_OUTBOUND	0
+#define PCIE_ATU_REGION_INDEX_MASK	GENMASK(3, 0)
+
+#define PCIE_ATU_CR1			0x0904
+#define PCIE_ATU_TYPE_MEM		0
+#define PCIE_ATU_TYPE_IO		2
+#define PCIE_ATU_TYPE_CFG0		4
+#define PCIE_ATU_TYPE_CFG1		5
+
+#define PCIE_ATU_CR2			0x0908
+#define PCIE_ATU_ENABLE			BIT(31)
+#define PCIE_ATU_MATCH_MODE		BIT(30)
+#define PCIE_ATU_BAR_NUM_MASK		GENMASK(10, 8)
+
+#define PCIE_ATU_LOWER_BASE		0x090C
+#define PCIE_ATU_UPPER_BASE		0x0910
+#define PCIE_ATU_LIMIT			0x0914
+#define PCIE_ATU_LOWER_TARGET		0x0918
+#define PCIE_ATU_BUS(x)			FIELD_PREP(GENMASK(31, 24), x)
+#define PCIE_ATU_DEV(x)			FIELD_PREP(GENMASK(23, 19), x)
+#define PCIE_ATU_FUNC(x)		FIELD_PREP(GENMASK(18, 16), x)
+#define PCIE_ATU_UPPER_TARGET		0x091C
+
+/* Link Glue registers */
+#define PCL_PINCTRL0			0x002c
+#define PCL_PERST_PLDN_REGEN		BIT(12)
+#define PCL_PERST_NOE_REGEN		BIT(11)
+#define PCL_PERST_OUT_REGEN		BIT(8)
+#define PCL_PERST_PLDN_REGVAL		BIT(4)
+#define PCL_PERST_NOE_REGVAL		BIT(3)
+#define PCL_PERST_OUT_REGVAL		BIT(0)
+
+#define PCL_MODE			0x8000
+#define PCL_MODE_REGEN			BIT(8)
+#define PCL_MODE_REGVAL			BIT(0)
+
+#define PCL_APP_READY_CTRL		0x8008
+#define PCL_APP_LTSSM_ENABLE		BIT(0)
+
+#define PCL_APP_PM0			0x8078
+#define PCL_SYS_AUX_PWR_DET		BIT(8)
+
+#define PCL_STATUS_LINK			0x8140
+#define PCL_RDLH_LINK_UP		BIT(1)
+#define PCL_XMLH_LINK_UP		BIT(0)
+
+#define LINK_UP_TIMEOUT_MS		100
+
+struct uniphier_pcie_priv {
+	void *base;
+	void *dbi_base;
+	void *cfg_base;
+	fdt_size_t cfg_size;
+	struct fdt_resource link_res;
+	struct fdt_resource dbi_res;
+	struct fdt_resource cfg_res;
+
+	struct clk clk;
+	struct reset_ctl rst;
+	struct phy phy;
+
+	struct pci_region io;
+	struct pci_region mem;
+};
+
+static int pcie_dw_get_link_speed(struct uniphier_pcie_priv *priv)
+{
+	u32 val = readl(priv->dbi_base + PCIE_LINK_STATUS_REG);
+
+	return FIELD_GET(PCIE_LINK_STATUS_SPEED_MASK, val);
+}
+
+static int pcie_dw_get_link_width(struct uniphier_pcie_priv *priv)
+{
+	u32 val = readl(priv->dbi_base + PCIE_LINK_STATUS_REG);
+
+	return FIELD_GET(PCIE_LINK_STATUS_WIDTH_MASK, val);
+}
+
+static void pcie_dw_prog_outbound_atu(struct uniphier_pcie_priv *priv,
+				      int index, int type, u64 cpu_addr,
+				      u64 pci_addr, u32 size)
+{
+	writel(PCIE_ATU_REGION_OUTBOUND
+	       | FIELD_PREP(PCIE_ATU_REGION_INDEX_MASK, index),
+	       priv->dbi_base + PCIE_ATU_VIEWPORT);
+	writel(lower_32_bits(cpu_addr),
+	       priv->dbi_base + PCIE_ATU_LOWER_BASE);
+	writel(upper_32_bits(cpu_addr),
+	       priv->dbi_base + PCIE_ATU_UPPER_BASE);
+	writel(lower_32_bits(cpu_addr + size - 1),
+	       priv->dbi_base + PCIE_ATU_LIMIT);
+	writel(lower_32_bits(pci_addr),
+	       priv->dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel(upper_32_bits(pci_addr),
+	       priv->dbi_base + PCIE_ATU_UPPER_TARGET);
+
+	writel(type, priv->dbi_base + PCIE_ATU_CR1);
+	writel(PCIE_ATU_ENABLE, priv->dbi_base + PCIE_ATU_CR2);
+}
+
+static int uniphier_pcie_addr_valid(pci_dev_t bdf, int first_busno)
+{
+	/* accept only device {0,1} on first bus */
+	if ((PCI_BUS(bdf) != first_busno) || (PCI_DEV(bdf) > 1))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int uniphier_pcie_conf_address(const struct udevice *dev, pci_dev_t bdf,
+				      uint offset, void **paddr)
+{
+	struct uniphier_pcie_priv *priv = dev_get_priv(dev);
+	u32 busdev;
+	int seq = dev_seq(dev);
+	int ret;
+
+	ret = uniphier_pcie_addr_valid(bdf, seq);
+	if (ret)
+		return ret;
+
+	if ((PCI_BUS(bdf) == seq) && !PCI_DEV(bdf)) {
+		*paddr = (void *)(priv->dbi_base + offset);
+		return 0;
+	}
+
+	busdev = PCIE_ATU_BUS(PCI_BUS(bdf) - seq)
+		| PCIE_ATU_DEV(PCI_DEV(bdf))
+		| PCIE_ATU_FUNC(PCI_FUNC(bdf));
+
+	pcie_dw_prog_outbound_atu(priv, 0,
+				  PCIE_ATU_TYPE_CFG0, (u64)priv->cfg_base,
+				  busdev, priv->cfg_size);
+	*paddr = (void *)(priv->cfg_base + offset);
+
+	return 0;
+}
+
+static int uniphier_pcie_read_config(const struct udevice *dev, pci_dev_t bdf,
+				     uint offset, ulong *valp,
+				     enum pci_size_t size)
+{
+	return pci_generic_mmap_read_config(dev, uniphier_pcie_conf_address,
+					    bdf, offset, valp, size);
+}
+
+static int uniphier_pcie_write_config(struct udevice *dev, pci_dev_t bdf,
+				      uint offset, ulong val,
+				      enum pci_size_t size)
+{
+	return pci_generic_mmap_write_config(dev, uniphier_pcie_conf_address,
+					     bdf, offset, val, size);
+}
+
+static void uniphier_pcie_ltssm_enable(struct uniphier_pcie_priv *priv,
+				       bool enable)
+{
+	u32 val;
+
+	val = readl(priv->base + PCL_APP_READY_CTRL);
+	if (enable)
+		val |= PCL_APP_LTSSM_ENABLE;
+	else
+		val &= ~PCL_APP_LTSSM_ENABLE;
+	writel(val, priv->base + PCL_APP_READY_CTRL);
+}
+
+static int uniphier_pcie_link_up(struct uniphier_pcie_priv *priv)
+{
+	u32 val, mask;
+
+	val = readl(priv->base + PCL_STATUS_LINK);
+	mask = PCL_RDLH_LINK_UP | PCL_XMLH_LINK_UP;
+
+	return (val & mask) == mask;
+}
+
+static int uniphier_pcie_wait_link(struct uniphier_pcie_priv *priv)
+{
+	unsigned long timeout;
+
+	timeout = get_timer(0) + LINK_UP_TIMEOUT_MS;
+
+	while (get_timer(0) < timeout) {
+		if (uniphier_pcie_link_up(priv))
+			return 0;
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int uniphier_pcie_establish_link(struct uniphier_pcie_priv *priv)
+{
+	if (uniphier_pcie_link_up(priv))
+		return 0;
+
+	uniphier_pcie_ltssm_enable(priv, true);
+
+	return uniphier_pcie_wait_link(priv);
+}
+
+static void uniphier_pcie_init_rc(struct uniphier_pcie_priv *priv)
+{
+	u32 val;
+
+	/* set RC mode */
+	val = readl(priv->base + PCL_MODE);
+	val |= PCL_MODE_REGEN;
+	val &= ~PCL_MODE_REGVAL;
+	writel(val, priv->base + PCL_MODE);
+
+	/* use auxiliary power detection */
+	val = readl(priv->base + PCL_APP_PM0);
+	val |= PCL_SYS_AUX_PWR_DET;
+	writel(val, priv->base + PCL_APP_PM0);
+
+	/* assert PERST# */
+	val = readl(priv->base + PCL_PINCTRL0);
+	val &= ~(PCL_PERST_NOE_REGVAL | PCL_PERST_OUT_REGVAL
+		 | PCL_PERST_PLDN_REGVAL);
+	val |= PCL_PERST_NOE_REGEN | PCL_PERST_OUT_REGEN
+		| PCL_PERST_PLDN_REGEN;
+	writel(val, priv->base + PCL_PINCTRL0);
+
+	uniphier_pcie_ltssm_enable(priv, false);
+
+	mdelay(100);
+
+	/* deassert PERST# */
+	val = readl(priv->base + PCL_PINCTRL0);
+	val |= PCL_PERST_OUT_REGVAL | PCL_PERST_OUT_REGEN;
+	writel(val, priv->base + PCL_PINCTRL0);
+}
+
+static void uniphier_pcie_setup_rc(struct uniphier_pcie_priv *priv,
+				   struct pci_controller *hose)
+{
+	/* Store the IO and MEM windows settings for future use by the ATU */
+	priv->io.phys_start  = hose->regions[0].phys_start; /* IO base */
+	priv->io.bus_start   = hose->regions[0].bus_start;  /* IO_bus_addr */
+	priv->io.size	     = hose->regions[0].size;	    /* IO size */
+	priv->mem.phys_start = hose->regions[1].phys_start; /* MEM base */
+	priv->mem.bus_start  = hose->regions[1].bus_start;  /* MEM_bus_addr */
+	priv->mem.size	     = hose->regions[1].size;	    /* MEM size */
+
+	/* outbound: IO */
+	pcie_dw_prog_outbound_atu(priv, 0,
+				  PCIE_ATU_TYPE_IO, priv->io.phys_start,
+				  priv->io.bus_start, priv->io.size);
+
+	/* outbound: MEM */
+	pcie_dw_prog_outbound_atu(priv, 1,
+				  PCIE_ATU_TYPE_MEM, priv->mem.phys_start,
+				  priv->mem.bus_start, priv->mem.size);
+}
+
+static int uniphier_pcie_probe(struct udevice *dev)
+{
+	struct uniphier_pcie_priv *priv = dev_get_priv(dev);
+	struct udevice *ctlr = pci_get_controller(dev);
+	struct pci_controller *hose = dev_get_uclass_priv(ctlr);
+	int ret;
+
+	priv->base = map_physmem(priv->link_res.start,
+				 fdt_resource_size(&priv->link_res),
+				 MAP_NOCACHE);
+	priv->dbi_base = map_physmem(priv->dbi_res.start,
+				     fdt_resource_size(&priv->dbi_res),
+				     MAP_NOCACHE);
+	priv->cfg_size = fdt_resource_size(&priv->cfg_res);
+	priv->cfg_base = map_physmem(priv->cfg_res.start,
+				     priv->cfg_size, MAP_NOCACHE);
+
+	ret = clk_enable(&priv->clk);
+	if (ret) {
+		dev_err(dev, "Failed to enable clk: %d\n", ret);
+		return ret;
+	}
+	ret = reset_deassert(&priv->rst);
+	if (ret) {
+		dev_err(dev, "Failed to deassert reset: %d\n", ret);
+		goto out_clk_release;
+	}
+
+	ret = generic_phy_init(&priv->phy);
+	if (ret) {
+		dev_err(dev, "Failed to initialize phy: %d\n", ret);
+		goto out_reset_release;
+	}
+
+	ret = generic_phy_power_on(&priv->phy);
+	if (ret) {
+		dev_err(dev, "Failed to power on phy: %d\n", ret);
+		goto out_phy_exit;
+	}
+
+	uniphier_pcie_init_rc(priv);
+
+	/* set DBI to read only */
+	writel(0, priv->dbi_base + PCIE_MISC_CONTROL_1_OFF);
+
+	uniphier_pcie_setup_rc(priv, hose);
+
+	if (uniphier_pcie_establish_link(priv)) {
+		printf("PCIE-%d: Link down\n", dev_seq(dev));
+	} else {
+		printf("PCIE-%d: Link up (Gen%d-x%d, Bus%d)\n",
+		       dev_seq(dev), pcie_dw_get_link_speed(priv),
+		       pcie_dw_get_link_width(priv), hose->first_busno);
+	}
+
+	return 0;
+
+out_phy_exit:
+	generic_phy_exit(&priv->phy);
+out_reset_release:
+	reset_release_all(&priv->rst, 1);
+out_clk_release:
+	clk_release_all(&priv->clk, 1);
+
+	return ret;
+}
+
+static int uniphier_pcie_of_to_plat(struct udevice *dev)
+{
+	struct uniphier_pcie_priv *priv = dev_get_priv(dev);
+	const void *fdt = gd->fdt_blob;
+	int node = dev_of_offset(dev);
+	int ret;
+
+	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
+				     "link", &priv->link_res);
+	if (ret) {
+		dev_err(dev, "Failed to get link regs: %d\n", ret);
+		return ret;
+	}
+
+	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
+				     "dbi", &priv->dbi_res);
+	if (ret) {
+		dev_err(dev, "Failed to get dbi regs: %d\n", ret);
+		return ret;
+	}
+
+	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
+				     "config", &priv->cfg_res);
+	if (ret) {
+		dev_err(dev, "Failed to get config regs: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_get_by_index(dev, 0, &priv->clk);
+	if (ret) {
+		dev_err(dev, "Failed to get clocks property: %d\n", ret);
+		return ret;
+	}
+
+	ret = reset_get_by_index(dev, 0, &priv->rst);
+	if (ret) {
+		dev_err(dev, "Failed to get resets property: %d\n", ret);
+		return ret;
+	}
+
+	ret = generic_phy_get_by_index(dev, 0, &priv->phy);
+	if (ret) {
+		dev_err(dev, "Failed to get phy property: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct dm_pci_ops uniphier_pcie_ops = {
+	.read_config	= uniphier_pcie_read_config,
+	.write_config	= uniphier_pcie_write_config,
+};
+
+static const struct udevice_id uniphier_pcie_ids[] = {
+	{ .compatible = "socionext,uniphier-pcie", },
+	{ /* Sentinel */ }
+};
+
+U_BOOT_DRIVER(pcie_uniphier) = {
+	.name     = "uniphier-pcie",
+	.id       = UCLASS_PCI,
+	.of_match = uniphier_pcie_ids,
+	.probe    = uniphier_pcie_probe,
+	.ops      = &uniphier_pcie_ops,
+	.of_to_plat = uniphier_pcie_of_to_plat,
+	.priv_auto = sizeof(struct uniphier_pcie_priv),
+};