PCI: Move DesignWare IP support to new drivers/pci/dwc/ directory

Group all the PCI drivers that use DesignWare core in dwc directory.
dwc IP is capable of operating in both host mode and device mode and
keeping it inside the *host* directory is misleading.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Acked-By: Joao Pinto <jpinto@synopsys.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Minghuan Lian <minghuan.Lian@freescale.com>
Cc: Mingkai Hu <mingkai.hu@freescale.com>
Cc: Roy Zang <tie-fei.zang@freescale.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Murali Karicheri <m-karicheri2@ti.com>
Cc: Pratyush Anand <pratyush.anand@gmail.com>
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Zhou Wang <wangzhou1@hisilicon.com>
Cc: Gabriele Paoloni <gabriele.paoloni@huawei.com>
Cc: Stanimir Varbanov <svarbanov@mm-sol.com>

1 files changed, 283 insertions, 0 deletions

diff --git a/drivers/pci/dwc/pcie-artpec6.c b/drivers/pci/dwc/pcie-artpec6.c
new file mode 100644
index 000000000000..212786b27f1a
--- /dev/null
+++ b/drivers/pci/dwc/pcie-artpec6.c
@@ -0,0 +1,283 @@
+/*
+ * PCIe host controller driver for Axis ARTPEC-6 SoC
+ *
+ * Author: Niklas Cassel <niklas.cassel@axis.com>
+ *
+ * Based on work done by Phil Edworthy <phil@edworthys.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "pcie-designware.h"
+
+#define to_artpec6_pcie(x)	container_of(x, struct artpec6_pcie, pp)
+
+struct artpec6_pcie {
+	struct pcie_port	pp;		/* pp.dbi_base is DT dbi */
+	struct regmap		*regmap;	/* DT axis,syscon-pcie */
+	void __iomem		*phy_base;	/* DT phy */
+};
+
+/* PCIe Port Logic registers (memory-mapped) */
+#define PL_OFFSET			0x700
+#define PCIE_PHY_DEBUG_R0		(PL_OFFSET + 0x28)
+#define PCIE_PHY_DEBUG_R1		(PL_OFFSET + 0x2c)
+
+#define MISC_CONTROL_1_OFF		(PL_OFFSET + 0x1bc)
+#define  DBI_RO_WR_EN			1
+
+/* ARTPEC-6 specific registers */
+#define PCIECFG				0x18
+#define  PCIECFG_DBG_OEN		(1 << 24)
+#define  PCIECFG_CORE_RESET_REQ		(1 << 21)
+#define  PCIECFG_LTSSM_ENABLE		(1 << 20)
+#define  PCIECFG_CLKREQ_B		(1 << 11)
+#define  PCIECFG_REFCLK_ENABLE		(1 << 10)
+#define  PCIECFG_PLL_ENABLE		(1 << 9)
+#define  PCIECFG_PCLK_ENABLE		(1 << 8)
+#define  PCIECFG_RISRCREN		(1 << 4)
+#define  PCIECFG_MODE_TX_DRV_EN		(1 << 3)
+#define  PCIECFG_CISRREN		(1 << 2)
+#define  PCIECFG_MACRO_ENABLE		(1 << 0)
+
+#define NOCCFG				0x40
+#define NOCCFG_ENABLE_CLK_PCIE		(1 << 4)
+#define NOCCFG_POWER_PCIE_IDLEACK	(1 << 3)
+#define NOCCFG_POWER_PCIE_IDLE		(1 << 2)
+#define NOCCFG_POWER_PCIE_IDLEREQ	(1 << 1)
+
+#define PHY_STATUS			0x118
+#define PHY_COSPLLLOCK			(1 << 0)
+
+#define ARTPEC6_CPU_TO_BUS_ADDR		0x0fffffff
+
+static u32 artpec6_pcie_readl(struct artpec6_pcie *artpec6_pcie, u32 offset)
+{
+	u32 val;
+
+	regmap_read(artpec6_pcie->regmap, offset, &val);
+	return val;
+}
+
+static void artpec6_pcie_writel(struct artpec6_pcie *artpec6_pcie, u32 offset, u32 val)
+{
+	regmap_write(artpec6_pcie->regmap, offset, val);
+}
+
+static int artpec6_pcie_establish_link(struct artpec6_pcie *artpec6_pcie)
+{
+	struct pcie_port *pp = &artpec6_pcie->pp;
+	u32 val;
+	unsigned int retries;
+
+	/* Hold DW core in reset */
+	val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
+	val |= PCIECFG_CORE_RESET_REQ;
+	artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
+
+	val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
+	val |=  PCIECFG_RISRCREN |	/* Receiver term. 50 Ohm */
+		PCIECFG_MODE_TX_DRV_EN |
+		PCIECFG_CISRREN |	/* Reference clock term. 100 Ohm */
+		PCIECFG_MACRO_ENABLE;
+	val |= PCIECFG_REFCLK_ENABLE;
+	val &= ~PCIECFG_DBG_OEN;
+	val &= ~PCIECFG_CLKREQ_B;
+	artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
+	usleep_range(5000, 6000);
+
+	val = artpec6_pcie_readl(artpec6_pcie, NOCCFG);
+	val |= NOCCFG_ENABLE_CLK_PCIE;
+	artpec6_pcie_writel(artpec6_pcie, NOCCFG, val);
+	usleep_range(20, 30);
+
+	val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
+	val |= PCIECFG_PCLK_ENABLE | PCIECFG_PLL_ENABLE;
+	artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
+	usleep_range(6000, 7000);
+
+	val = artpec6_pcie_readl(artpec6_pcie, NOCCFG);
+	val &= ~NOCCFG_POWER_PCIE_IDLEREQ;
+	artpec6_pcie_writel(artpec6_pcie, NOCCFG, val);
+
+	retries = 50;
+	do {
+		usleep_range(1000, 2000);
+		val = artpec6_pcie_readl(artpec6_pcie, NOCCFG);
+		retries--;
+	} while (retries &&
+		(val & (NOCCFG_POWER_PCIE_IDLEACK | NOCCFG_POWER_PCIE_IDLE)));
+
+	retries = 50;
+	do {
+		usleep_range(1000, 2000);
+		val = readl(artpec6_pcie->phy_base + PHY_STATUS);
+		retries--;
+	} while (retries && !(val & PHY_COSPLLLOCK));
+
+	/* Take DW core out of reset */
+	val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
+	val &= ~PCIECFG_CORE_RESET_REQ;
+	artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
+	usleep_range(100, 200);
+
+	/*
+	 * Enable writing to config regs. This is required as the Synopsys
+	 * driver changes the class code. That register needs DBI write enable.
+	 */
+	dw_pcie_writel_rc(pp, MISC_CONTROL_1_OFF, DBI_RO_WR_EN);
+
+	pp->io_base &= ARTPEC6_CPU_TO_BUS_ADDR;
+	pp->mem_base &= ARTPEC6_CPU_TO_BUS_ADDR;
+	pp->cfg0_base &= ARTPEC6_CPU_TO_BUS_ADDR;
+	pp->cfg1_base &= ARTPEC6_CPU_TO_BUS_ADDR;
+
+	/* setup root complex */
+	dw_pcie_setup_rc(pp);
+
+	/* assert LTSSM enable */
+	val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
+	val |= PCIECFG_LTSSM_ENABLE;
+	artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
+
+	/* check if the link is up or not */
+	if (!dw_pcie_wait_for_link(pp))
+		return 0;
+
+	dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
+		dw_pcie_readl_rc(pp, PCIE_PHY_DEBUG_R0),
+		dw_pcie_readl_rc(pp, PCIE_PHY_DEBUG_R1));
+
+	return -ETIMEDOUT;
+}
+
+static void artpec6_pcie_enable_interrupts(struct artpec6_pcie *artpec6_pcie)
+{
+	struct pcie_port *pp = &artpec6_pcie->pp;
+
+	if (IS_ENABLED(CONFIG_PCI_MSI))
+		dw_pcie_msi_init(pp);
+}
+
+static void artpec6_pcie_host_init(struct pcie_port *pp)
+{
+	struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pp);
+
+	artpec6_pcie_establish_link(artpec6_pcie);
+	artpec6_pcie_enable_interrupts(artpec6_pcie);
+}
+
+static struct pcie_host_ops artpec6_pcie_host_ops = {
+	.host_init = artpec6_pcie_host_init,
+};
+
+static irqreturn_t artpec6_pcie_msi_handler(int irq, void *arg)
+{
+	struct artpec6_pcie *artpec6_pcie = arg;
+	struct pcie_port *pp = &artpec6_pcie->pp;
+
+	return dw_handle_msi_irq(pp);
+}
+
+static int artpec6_add_pcie_port(struct artpec6_pcie *artpec6_pcie,
+				 struct platform_device *pdev)
+{
+	struct pcie_port *pp = &artpec6_pcie->pp;
+	struct device *dev = pp->dev;
+	int ret;
+
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		pp->msi_irq = platform_get_irq_byname(pdev, "msi");
+		if (pp->msi_irq <= 0) {
+			dev_err(dev, "failed to get MSI irq\n");
+			return -ENODEV;
+		}
+
+		ret = devm_request_irq(dev, pp->msi_irq,
+				       artpec6_pcie_msi_handler,
+				       IRQF_SHARED | IRQF_NO_THREAD,
+				       "artpec6-pcie-msi", artpec6_pcie);
+		if (ret) {
+			dev_err(dev, "failed to request MSI irq\n");
+			return ret;
+		}
+	}
+
+	pp->root_bus_nr = -1;
+	pp->ops = &artpec6_pcie_host_ops;
+
+	ret = dw_pcie_host_init(pp);
+	if (ret) {
+		dev_err(dev, "failed to initialize host\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int artpec6_pcie_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct artpec6_pcie *artpec6_pcie;
+	struct pcie_port *pp;
+	struct resource *dbi_base;
+	struct resource *phy_base;
+	int ret;
+
+	artpec6_pcie = devm_kzalloc(dev, sizeof(*artpec6_pcie), GFP_KERNEL);
+	if (!artpec6_pcie)
+		return -ENOMEM;
+
+	pp = &artpec6_pcie->pp;
+	pp->dev = dev;
+
+	dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
+	pp->dbi_base = devm_ioremap_resource(dev, dbi_base);
+	if (IS_ERR(pp->dbi_base))
+		return PTR_ERR(pp->dbi_base);
+
+	phy_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "phy");
+	artpec6_pcie->phy_base = devm_ioremap_resource(dev, phy_base);
+	if (IS_ERR(artpec6_pcie->phy_base))
+		return PTR_ERR(artpec6_pcie->phy_base);
+
+	artpec6_pcie->regmap =
+		syscon_regmap_lookup_by_phandle(dev->of_node,
+						"axis,syscon-pcie");
+	if (IS_ERR(artpec6_pcie->regmap))
+		return PTR_ERR(artpec6_pcie->regmap);
+
+	ret = artpec6_add_pcie_port(artpec6_pcie, pdev);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static const struct of_device_id artpec6_pcie_of_match[] = {
+	{ .compatible = "axis,artpec6-pcie", },
+	{},
+};
+
+static struct platform_driver artpec6_pcie_driver = {
+	.probe = artpec6_pcie_probe,
+	.driver = {
+		.name	= "artpec6-pcie",
+		.of_match_table = artpec6_pcie_of_match,
+	},
+};
+builtin_platform_driver(artpec6_pcie_driver);