drivers/pci/controller/dwc/pcie-spear13xx.c - third_party/linux - Git at Google

 // 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);
	// 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);