1 files changed, 314 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-spear13xx.c b/drivers/pci/controller/dwc/pcie-spear13xx.c
new file mode 100644
index 000000000000..ecb58f7b7566
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-spear13xx.c
@@ -0,0 +1,314 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCIe host controller driver for ST Microelectronics SPEAr13xx SoCs
+ *
+ * SPEAr13xx PCIe Glue Layer Source Code
+ *
+ * Copyright (C) 2010-2014 ST Microelectronics
+ * Pratyush Anand <pratyush.anand@gmail.com>
+ * Mohit Kumar <mohit.kumar.dhaka@gmail.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/pci.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+
+#include "pcie-designware.h"
+
+struct spear13xx_pcie {
+	struct dw_pcie		*pci;
+	void __iomem		*app_base;
+	struct phy		*phy;
+	struct clk		*clk;
+	bool			is_gen1;
+};
+
+struct pcie_app_reg {
+	u32	app_ctrl_0;		/* cr0 */
+	u32	app_ctrl_1;		/* cr1 */
+	u32	app_status_0;		/* cr2 */
+	u32	app_status_1;		/* cr3 */
+	u32	msg_status;		/* cr4 */
+	u32	msg_payload;		/* cr5 */
+	u32	int_sts;		/* cr6 */
+	u32	int_clr;		/* cr7 */
+	u32	int_mask;		/* cr8 */
+	u32	mst_bmisc;		/* cr9 */
+	u32	phy_ctrl;		/* cr10 */
+	u32	phy_status;		/* cr11 */
+	u32	cxpl_debug_info_0;	/* cr12 */
+	u32	cxpl_debug_info_1;	/* cr13 */
+	u32	ven_msg_ctrl_0;		/* cr14 */
+	u32	ven_msg_ctrl_1;		/* cr15 */
+	u32	ven_msg_data_0;		/* cr16 */
+	u32	ven_msg_data_1;		/* cr17 */
+	u32	ven_msi_0;		/* cr18 */
+	u32	ven_msi_1;		/* cr19 */
+	u32	mst_rmisc;		/* cr20 */
+};
+
+/* CR0 ID */
+#define APP_LTSSM_ENABLE_ID			3
+#define DEVICE_TYPE_RC				(4 << 25)
+#define MISCTRL_EN_ID				30
+#define REG_TRANSLATION_ENABLE			31
+
+/* CR3 ID */
+#define XMLH_LINK_UP				(1 << 6)
+
+/* CR6 */
+#define MSI_CTRL_INT				(1 << 26)
+
+#define EXP_CAP_ID_OFFSET			0x70
+
+#define to_spear13xx_pcie(x)	dev_get_drvdata((x)->dev)
+
+static int spear13xx_pcie_establish_link(struct spear13xx_pcie *spear13xx_pcie)
+{
+	struct dw_pcie *pci = spear13xx_pcie->pci;
+	struct pcie_port *pp = &pci->pp;
+	struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+	u32 val;
+	u32 exp_cap_off = EXP_CAP_ID_OFFSET;
+
+	if (dw_pcie_link_up(pci)) {
+		dev_err(pci->dev, "link already up\n");
+		return 0;
+	}
+
+	dw_pcie_setup_rc(pp);
+
+	/*
+	 * this controller support only 128 bytes read size, however its
+	 * default value in capability register is 512 bytes. So force
+	 * it to 128 here.
+	 */
+	dw_pcie_read(pci->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, &val);
+	val &= ~PCI_EXP_DEVCTL_READRQ;
+	dw_pcie_write(pci->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, val);
+
+	dw_pcie_write(pci->dbi_base + PCI_VENDOR_ID, 2, 0x104A);
+	dw_pcie_write(pci->dbi_base + PCI_DEVICE_ID, 2, 0xCD80);
+
+	/*
+	 * if is_gen1 is set then handle it, so that some buggy card
+	 * also works
+	 */
+	if (spear13xx_pcie->is_gen1) {
+		dw_pcie_read(pci->dbi_base + exp_cap_off + PCI_EXP_LNKCAP,
+			     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_write(pci->dbi_base + exp_cap_off +
+				      PCI_EXP_LNKCAP, 4, val);
+		}
+
+		dw_pcie_read(pci->dbi_base + exp_cap_off + PCI_EXP_LNKCTL2,
+			     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_write(pci->dbi_base + exp_cap_off +
+				      PCI_EXP_LNKCTL2, 2, val);
+		}
+	}
+
+	/* enable ltssm */
+	writel(DEVICE_TYPE_RC | (1 << MISCTRL_EN_ID)
+			| (1 << APP_LTSSM_ENABLE_ID)
+			| ((u32)1 << REG_TRANSLATION_ENABLE),
+			&app_reg->app_ctrl_0);
+
+	return dw_pcie_wait_for_link(pci);
+}
+
+static irqreturn_t spear13xx_pcie_irq_handler(int irq, void *arg)
+{
+	struct spear13xx_pcie *spear13xx_pcie = arg;
+	struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+	struct dw_pcie *pci = spear13xx_pcie->pci;
+	struct pcie_port *pp = &pci->pp;
+	unsigned int status;
+
+	status = readl(&app_reg->int_sts);
+
+	if (status & MSI_CTRL_INT) {
+		BUG_ON(!IS_ENABLED(CONFIG_PCI_MSI));
+		dw_handle_msi_irq(pp);
+	}
+
+	writel(status, &app_reg->int_clr);
+
+	return IRQ_HANDLED;
+}
+
+static void spear13xx_pcie_enable_interrupts(struct spear13xx_pcie *spear13xx_pcie)
+{
+	struct dw_pcie *pci = spear13xx_pcie->pci;
+	struct pcie_port *pp = &pci->pp;
+	struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+
+	/* Enable MSI interrupt */
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		dw_pcie_msi_init(pp);
+		writel(readl(&app_reg->int_mask) |
+				MSI_CTRL_INT, &app_reg->int_mask);
+	}
+}
+
+static int spear13xx_pcie_link_up(struct dw_pcie *pci)
+{
+	struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci);
+	struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
+
+	if (readl(&app_reg->app_status_1) & XMLH_LINK_UP)
+		return 1;
+
+	return 0;
+}
+
+static int spear13xx_pcie_host_init(struct pcie_port *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pci);
+
+	spear13xx_pcie_establish_link(spear13xx_pcie);
+	spear13xx_pcie_enable_interrupts(spear13xx_pcie);
+
+	return 0;
+}
+
+static const struct dw_pcie_host_ops spear13xx_pcie_host_ops = {
+	.host_init = spear13xx_pcie_host_init,
+};
+
+static int spear13xx_add_pcie_port(struct spear13xx_pcie *spear13xx_pcie,
+				   struct platform_device *pdev)
+{
+	struct dw_pcie *pci = spear13xx_pcie->pci;
+	struct pcie_port *pp = &pci->pp;
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	pp->irq = platform_get_irq(pdev, 0);
+	if (pp->irq < 0) {
+		dev_err(dev, "failed to get irq\n");
+		return pp->irq;
+	}
+	ret = devm_request_irq(dev, pp->irq, spear13xx_pcie_irq_handler,
+			       IRQF_SHARED | IRQF_NO_THREAD,
+			       "spear1340-pcie", spear13xx_pcie);
+	if (ret) {
+		dev_err(dev, "failed to request irq %d\n", pp->irq);
+		return ret;
+	}
+
+	pp->root_bus_nr = -1;
+	pp->ops = &spear13xx_pcie_host_ops;
+
+	ret = dw_pcie_host_init(pp);
+	if (ret) {
+		dev_err(dev, "failed to initialize host\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct dw_pcie_ops dw_pcie_ops = {
+	.link_up = spear13xx_pcie_link_up,
+};
+
+static int spear13xx_pcie_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct dw_pcie *pci;
+	struct spear13xx_pcie *spear13xx_pcie;
+	struct device_node *np = dev->of_node;
+	struct resource *dbi_base;
+	int ret;
+
+	spear13xx_pcie = devm_kzalloc(dev, sizeof(*spear13xx_pcie), GFP_KERNEL);
+	if (!spear13xx_pcie)
+		return -ENOMEM;
+
+	pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
+	if (!pci)
+		return -ENOMEM;
+
+	pci->dev = dev;
+	pci->ops = &dw_pcie_ops;
+
+	spear13xx_pcie->pci = pci;
+
+	spear13xx_pcie->phy = devm_phy_get(dev, "pcie-phy");
+	if (IS_ERR(spear13xx_pcie->phy)) {
+		ret = PTR_ERR(spear13xx_pcie->phy);
+		if (ret == -EPROBE_DEFER)
+			dev_info(dev, "probe deferred\n");
+		else
+			dev_err(dev, "couldn't get pcie-phy\n");
+		return ret;
+	}
+
+	phy_init(spear13xx_pcie->phy);
+
+	spear13xx_pcie->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(spear13xx_pcie->clk)) {
+		dev_err(dev, "couldn't get clk for pcie\n");
+		return PTR_ERR(spear13xx_pcie->clk);
+	}
+	ret = clk_prepare_enable(spear13xx_pcie->clk);
+	if (ret) {
+		dev_err(dev, "couldn't enable clk for pcie\n");
+		return ret;
+	}
+
+	dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
+	pci->dbi_base = devm_pci_remap_cfg_resource(dev, dbi_base);
+	if (IS_ERR(pci->dbi_base)) {
+		dev_err(dev, "couldn't remap dbi base %p\n", dbi_base);
+		ret = PTR_ERR(pci->dbi_base);
+		goto fail_clk;
+	}
+	spear13xx_pcie->app_base = pci->dbi_base + 0x2000;
+
+	if (of_property_read_bool(np, "st,pcie-is-gen1"))
+		spear13xx_pcie->is_gen1 = true;
+
+	platform_set_drvdata(pdev, spear13xx_pcie);
+
+	ret = spear13xx_add_pcie_port(spear13xx_pcie, pdev);
+	if (ret < 0)
+		goto fail_clk;
+
+	return 0;
+
+fail_clk:
+	clk_disable_unprepare(spear13xx_pcie->clk);
+
+	return ret;
+}
+
+static const struct of_device_id spear13xx_pcie_of_match[] = {
+	{ .compatible = "st,spear1340-pcie", },
+	{},
+};
+
+static struct platform_driver spear13xx_pcie_driver = {
+	.probe		= spear13xx_pcie_probe,
+	.driver = {
+		.name	= "spear-pcie",
+		.of_match_table = of_match_ptr(spear13xx_pcie_of_match),
+		.suppress_bind_attrs = true,
+	},
+};
+
+builtin_platform_driver(spear13xx_pcie_driver);