starfive: pci: Add StarFive JH7110 pcie driver

Add pcie driver for StarFive JH7110, Also add PLDA
PCIe controller common driver functions.

Several devices are tested:
a) M.2 NVMe SSD
b) Realtek 8169 Ethernet adapter.

Signed-off-by: Mason Huo <mason.huo@starfivetech.com>
Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
Acked-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>

1 files changed, 317 insertions, 0 deletions

diff --git a/drivers/pci/pcie_starfive_jh7110.c b/drivers/pci/pcie_starfive_jh7110.c
new file mode 100644
index 00000000000..903a544d37f
--- /dev/null
+++ b/drivers/pci/pcie_starfive_jh7110.c
@@ -0,0 +1,317 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * StarFive PLDA PCIe host controller driver
+ *
+ * Copyright (C) 2023 StarFive Technology Co., Ltd.
+ * Author: Mason Huo <mason.huo@starfivetech.com>
+ *
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <pci.h>
+#include <pci_ids.h>
+#include <power-domain.h>
+#include <regmap.h>
+#include <reset.h>
+#include <syscon.h>
+#include <asm/global_data.h>
+#include <asm/io.h>
+#include <asm-generic/gpio.h>
+#include <dm/device_compat.h>
+#include <dm/pinctrl.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+#include "pcie_plda_common.h"
+
+/* system control */
+#define STG_SYSCON_K_RP_NEP_MASK               BIT(8)
+#define STG_SYSCON_AXI4_SLVL_ARFUNC_MASK       GENMASK(22, 8)
+#define STG_SYSCON_AXI4_SLVL_ARFUNC_SHIFT      8
+#define STG_SYSCON_AXI4_SLVL_AWFUNC_MASK       GENMASK(14, 0)
+#define STG_SYSCON_CLKREQ_MASK                 BIT(22)
+#define STG_SYSCON_CKREF_SRC_SHIFT             18
+#define STG_SYSCON_CKREF_SRC_MASK              GENMASK(19, 18)
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct starfive_pcie {
+	struct pcie_plda plda;
+	struct clk_bulk	clks;
+	struct reset_ctl_bulk	rsts;
+	struct gpio_desc	reset_gpio;
+	struct regmap *regmap;
+	u32 stg_arfun;
+	u32 stg_awfun;
+	u32 stg_rp_nep;
+};
+
+static int starfive_pcie_atr_init(struct starfive_pcie *priv)
+{
+	struct udevice *ctlr = pci_get_controller(priv->plda.dev);
+	struct pci_controller *hose = dev_get_uclass_priv(ctlr);
+	int i, ret;
+
+	/*
+	 * As the two host bridges in JH7110 soc have the same default
+	 * address translation table, this cause the second root port can't
+	 * access it's host bridge config space correctly.
+	 * To workaround, config the ATR of host bridge config space by SW.
+	 */
+
+	ret = plda_pcie_set_atr_entry(&priv->plda,
+				      (phys_addr_t)priv->plda.cfg_base, 0,
+				      priv->plda.cfg_size,
+				      XR3PCI_ATR_TRSLID_PCIE_CONFIG);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < hose->region_count; i++) {
+		if (hose->regions[i].flags == PCI_REGION_SYS_MEMORY)
+			continue;
+
+		/* Only support identity mappings. */
+		if (hose->regions[i].bus_start !=
+		    hose->regions[i].phys_start)
+			return -EINVAL;
+
+		ret = plda_pcie_set_atr_entry(&priv->plda,
+					      hose->regions[i].phys_start,
+					      hose->regions[i].bus_start,
+					      hose->regions[i].size,
+					      XR3PCI_ATR_TRSLID_PCIE_MEMORY);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int starfive_pcie_get_syscon(struct udevice *dev)
+{
+	struct starfive_pcie *priv = dev_get_priv(dev);
+	struct udevice *syscon;
+	struct ofnode_phandle_args syscfg_phandle;
+	u32 cells[4];
+	int ret;
+
+	/* get corresponding syscon phandle */
+	ret = dev_read_phandle_with_args(dev, "starfive,stg-syscon", NULL, 0, 0,
+					 &syscfg_phandle);
+
+	if (ret < 0) {
+		dev_err(dev, "Can't get syscfg phandle: %d\n", ret);
+		return ret;
+	}
+
+	ret = uclass_get_device_by_ofnode(UCLASS_SYSCON, syscfg_phandle.node,
+					  &syscon);
+	if (ret) {
+		dev_err(dev, "Unable to find syscon device (%d)\n", ret);
+		return ret;
+	}
+
+	priv->regmap = syscon_get_regmap(syscon);
+	if (!priv->regmap) {
+		dev_err(dev, "Unable to find regmap\n");
+		return -ENODEV;
+	}
+
+	/* get syscon register offset */
+	ret = dev_read_u32_array(dev, "starfive,stg-syscon",
+				 cells, ARRAY_SIZE(cells));
+	if (ret) {
+		dev_err(dev, "Get syscon register err %d\n", ret);
+		return -EINVAL;
+	}
+
+	dev_dbg(dev, "Get syscon values: %x, %x, %x\n",
+		cells[1], cells[2], cells[3]);
+	priv->stg_arfun = cells[1];
+	priv->stg_awfun = cells[2];
+	priv->stg_rp_nep = cells[3];
+
+	return 0;
+}
+
+static int starfive_pcie_parse_dt(struct udevice *dev)
+{
+	struct starfive_pcie *priv = dev_get_priv(dev);
+	int ret;
+
+	priv->plda.reg_base = (void *)dev_read_addr_name(dev, "reg");
+	if (priv->plda.reg_base == (void __iomem *)FDT_ADDR_T_NONE) {
+		dev_err(dev, "Missing required reg address range\n");
+		return -EINVAL;
+	}
+
+	priv->plda.cfg_base =
+		(void *)dev_read_addr_size_name(dev,
+						"config",
+						&priv->plda.cfg_size);
+	if (priv->plda.cfg_base == (void __iomem *)FDT_ADDR_T_NONE) {
+		dev_err(dev, "Missing required config address range");
+		return -EINVAL;
+	}
+
+	ret = starfive_pcie_get_syscon(dev);
+	if (ret) {
+		dev_err(dev, "Can't get syscon: %d\n", ret);
+		return ret;
+	}
+
+	ret = reset_get_bulk(dev, &priv->rsts);
+	if (ret) {
+		dev_err(dev, "Can't get reset: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_get_bulk(dev, &priv->clks);
+	if (ret) {
+		dev_err(dev, "Can't get clock: %d\n", ret);
+		return ret;
+	}
+
+	ret = gpio_request_by_name(dev, "reset-gpios", 0, &priv->reset_gpio,
+				   GPIOD_IS_OUT);
+	if (ret) {
+		dev_err(dev, "Can't get reset-gpio: %d\n", ret);
+		return ret;
+	}
+
+	if (!dm_gpio_is_valid(&priv->reset_gpio)) {
+		dev_err(dev, "reset-gpio is not valid\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int starfive_pcie_init_port(struct udevice *dev)
+{
+	int ret, i;
+	struct starfive_pcie *priv = dev_get_priv(dev);
+	struct pcie_plda *plda = &priv->plda;
+
+	ret = clk_enable_bulk(&priv->clks);
+	if (ret) {
+		dev_err(dev, "Failed to enable clks (ret=%d)\n", ret);
+		return ret;
+	}
+
+	ret = reset_deassert_bulk(&priv->rsts);
+	if (ret) {
+		dev_err(dev, "Failed to deassert resets (ret=%d)\n", ret);
+		goto err_deassert_clk;
+	}
+
+	dm_gpio_set_value(&priv->reset_gpio, 1);
+	/* Disable physical functions except #0 */
+	for (i = 1; i < PLDA_FUNC_NUM; i++) {
+		regmap_update_bits(priv->regmap,
+				   priv->stg_arfun,
+				   STG_SYSCON_AXI4_SLVL_ARFUNC_MASK,
+				   (i << PLDA_PHY_FUNC_SHIFT) <<
+				   STG_SYSCON_AXI4_SLVL_ARFUNC_SHIFT);
+		regmap_update_bits(priv->regmap,
+				   priv->stg_awfun,
+				   STG_SYSCON_AXI4_SLVL_AWFUNC_MASK,
+				   i << PLDA_PHY_FUNC_SHIFT);
+
+		plda_pcie_disable_func(plda);
+	}
+
+	/* Disable physical functions */
+	regmap_update_bits(priv->regmap,
+			   priv->stg_arfun,
+			   STG_SYSCON_AXI4_SLVL_ARFUNC_MASK,
+			   0);
+	regmap_update_bits(priv->regmap,
+			   priv->stg_awfun,
+			   STG_SYSCON_AXI4_SLVL_AWFUNC_MASK,
+			   0);
+
+	plda_pcie_enable_root_port(plda);
+
+	/* PCIe PCI Standard Configuration Identification Settings. */
+	plda_pcie_set_standard_class(plda);
+
+	/*
+	 * The LTR message forwarding of PCIe Message Reception was set by core
+	 * as default, but the forward id & addr are also need to be reset.
+	 * If we do not disable LTR message forwarding here, or set a legal
+	 * forwarding address, the kernel will get stuck after this driver probe.
+	 * To workaround, disable the LTR message forwarding support on
+	 * PCIe Message Reception.
+	 */
+	plda_pcie_disable_ltr(plda);
+
+	/* Prefetchable memory window 64-bit addressing support */
+	plda_pcie_set_pref_win_64bit(plda);
+	starfive_pcie_atr_init(priv);
+
+	dm_gpio_set_value(&priv->reset_gpio, 0);
+	/* Ensure that PERST in default at least 300 ms */
+	mdelay(300);
+
+	return 0;
+
+err_deassert_clk:
+	clk_disable_bulk(&priv->clks);
+	return ret;
+}
+
+static int starfive_pcie_probe(struct udevice *dev)
+{
+	struct starfive_pcie *priv = dev_get_priv(dev);
+	int ret;
+
+	priv->plda.atr_table_num = 0;
+	priv->plda.dev = dev;
+
+	ret = starfive_pcie_parse_dt(dev);
+	if (ret)
+		return ret;
+
+	regmap_update_bits(priv->regmap,
+			   priv->stg_rp_nep,
+			   STG_SYSCON_K_RP_NEP_MASK,
+			   STG_SYSCON_K_RP_NEP_MASK);
+
+	regmap_update_bits(priv->regmap,
+			   priv->stg_awfun,
+			   STG_SYSCON_CKREF_SRC_MASK,
+			   2 << STG_SYSCON_CKREF_SRC_SHIFT);
+
+	regmap_update_bits(priv->regmap,
+			   priv->stg_awfun,
+			   STG_SYSCON_CLKREQ_MASK,
+			   STG_SYSCON_CLKREQ_MASK);
+
+	ret = starfive_pcie_init_port(dev);
+	if (ret)
+		return ret;
+
+	dev_err(dev, "Starfive PCIe bus probed.\n");
+
+	return 0;
+}
+
+static const struct dm_pci_ops starfive_pcie_ops = {
+	.read_config	= plda_pcie_config_read,
+	.write_config	= plda_pcie_config_write,
+};
+
+static const struct udevice_id starfive_pcie_ids[] = {
+	{ .compatible = "starfive,jh7110-pcie" },
+	{ }
+};
+
+U_BOOT_DRIVER(starfive_pcie_drv) = {
+	.name			= "starfive_7110_pcie",
+	.id			= UCLASS_PCI,
+	.of_match		= starfive_pcie_ids,
+	.ops			= &starfive_pcie_ops,
+	.probe			= starfive_pcie_probe,
+	.priv_auto	= sizeof(struct starfive_pcie),
+};