drivers/pci/host/pci-layerscape.c - kernel/quantenna - Git at Google

 /*
  * PCIe host controller driver for Freescale Layerscape SoCs
  *
  * Copyright (C) 2014 Freescale Semiconductor.
  *
  * Author: Minghuan Lian <Minghuan.Lian@freescale.com>
  *
  * 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/kernel.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/of_pci.h>
 #include <linux/of_platform.h>
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/resource.h>
 #include <linux/mfd/syscon.h>
 #include <linux/regmap.h>

 #include "pcie-designware.h"

 /* PEX1/2 Misc Ports Status Register */
 #define SCFG_PEXMSCPORTSR(pex_idx)	(0x94 + (pex_idx) * 4)
 #define LTSSM_STATE_SHIFT	20
 #define LTSSM_STATE_MASK	0x3f
 #define LTSSM_PCIE_L0		0x11 /* L0 state */

 /* PEX Internal Configuration Registers */
 #define PCIE_STRFMR1		0x71c /* Symbol Timer & Filter Mask Register1 */
 #define PCIE_DBI_RO_WR_EN	0x8bc /* DBI Read-Only Write Enable Register */

 /* PEX LUT registers */
 #define PCIE_LUT_DBG		0x7FC /* PEX LUT Debug Register */

 struct ls_pcie_drvdata {
 	u32 lut_offset;
 	u32 ltssm_shift;
 	struct pcie_host_ops *ops;
 };

 struct ls_pcie {
 	void __iomem *dbi;
 	void __iomem *lut;
 	struct regmap *scfg;
 	struct pcie_port pp;
 	const struct ls_pcie_drvdata *drvdata;
 	int index;
 };

 #define to_ls_pcie(x)	container_of(x, struct ls_pcie, pp)

 static bool ls_pcie_is_bridge(struct ls_pcie *pcie)
 {
 	u32 header_type;

 	header_type = ioread8(pcie->dbi + PCI_HEADER_TYPE);
 	header_type &= 0x7f;

 	return header_type == PCI_HEADER_TYPE_BRIDGE;
 }

 /* Clear multi-function bit */
 static void ls_pcie_clear_multifunction(struct ls_pcie *pcie)
 {
 	iowrite8(PCI_HEADER_TYPE_BRIDGE, pcie->dbi + PCI_HEADER_TYPE);
 }

 /* Fix class value */
 static void ls_pcie_fix_class(struct ls_pcie *pcie)
 {
 	iowrite16(PCI_CLASS_BRIDGE_PCI, pcie->dbi + PCI_CLASS_DEVICE);
 }

 /* Drop MSG TLP except for Vendor MSG */
 static void ls_pcie_drop_msg_tlp(struct ls_pcie *pcie)
 {
 	u32 val;

 	val = ioread32(pcie->dbi + PCIE_STRFMR1);
 	val &= 0xDFFFFFFF;
 	iowrite32(val, pcie->dbi + PCIE_STRFMR1);
 }

 static int ls1021_pcie_link_up(struct pcie_port *pp)
 {
 	u32 state;
 	struct ls_pcie *pcie = to_ls_pcie(pp);

 	if (!pcie->scfg)
 		return 0;

 	regmap_read(pcie->scfg, SCFG_PEXMSCPORTSR(pcie->index), &state);
 	state = (state >> LTSSM_STATE_SHIFT) & LTSSM_STATE_MASK;

 	if (state < LTSSM_PCIE_L0)
 		return 0;

 	return 1;
 }

 static void ls1021_pcie_host_init(struct pcie_port *pp)
 {
 	struct ls_pcie *pcie = to_ls_pcie(pp);
 	u32 index[2];

 	pcie->scfg = syscon_regmap_lookup_by_phandle(pp->dev->of_node,
 						     "fsl,pcie-scfg");
 	if (IS_ERR(pcie->scfg)) {
 		dev_err(pp->dev, "No syscfg phandle specified\n");
 		pcie->scfg = NULL;
 		return;
 	}

 	if (of_property_read_u32_array(pp->dev->of_node,
 				       "fsl,pcie-scfg", index, 2)) {
 		pcie->scfg = NULL;
 		return;
 	}
 	pcie->index = index[1];

 	dw_pcie_setup_rc(pp);

 	ls_pcie_drop_msg_tlp(pcie);
 }

 static int ls_pcie_link_up(struct pcie_port *pp)
 {
 	struct ls_pcie *pcie = to_ls_pcie(pp);
 	u32 state;

 	state = (ioread32(pcie->lut + PCIE_LUT_DBG) >>
 		 pcie->drvdata->ltssm_shift) &
 		 LTSSM_STATE_MASK;

 	if (state < LTSSM_PCIE_L0)
 		return 0;

 	return 1;
 }

 static void ls_pcie_host_init(struct pcie_port *pp)
 {
 	struct ls_pcie *pcie = to_ls_pcie(pp);

 	iowrite32(1, pcie->dbi + PCIE_DBI_RO_WR_EN);
 	ls_pcie_fix_class(pcie);
 	ls_pcie_clear_multifunction(pcie);
 	ls_pcie_drop_msg_tlp(pcie);
 	iowrite32(0, pcie->dbi + PCIE_DBI_RO_WR_EN);
 }

 static int ls_pcie_msi_host_init(struct pcie_port *pp,
 				 struct msi_controller *chip)
 {
 	struct device_node *msi_node;
 	struct device_node *np = pp->dev->of_node;

 	/*
 	 * The MSI domain is set by the generic of_msi_configure().  This
 	 * .msi_host_init() function keeps us from doing the default MSI
 	 * domain setup in dw_pcie_host_init() and also enforces the
 	 * requirement that "msi-parent" exists.
 	 */
 	msi_node = of_parse_phandle(np, "msi-parent", 0);
 	if (!msi_node) {
 		dev_err(pp->dev, "failed to find msi-parent\n");
 		return -EINVAL;
 	}

 	return 0;
 }

 static struct pcie_host_ops ls1021_pcie_host_ops = {
 	.link_up = ls1021_pcie_link_up,
 	.host_init = ls1021_pcie_host_init,
 	.msi_host_init = ls_pcie_msi_host_init,
 };

 static struct pcie_host_ops ls_pcie_host_ops = {
 	.link_up = ls_pcie_link_up,
 	.host_init = ls_pcie_host_init,
 	.msi_host_init = ls_pcie_msi_host_init,
 };

 static struct ls_pcie_drvdata ls1021_drvdata = {
 	.ops = &ls1021_pcie_host_ops,
 };

 static struct ls_pcie_drvdata ls1043_drvdata = {
 	.lut_offset = 0x10000,
 	.ltssm_shift = 24,
 	.ops = &ls_pcie_host_ops,
 };

 static struct ls_pcie_drvdata ls2080_drvdata = {
 	.lut_offset = 0x80000,
 	.ltssm_shift = 0,
 	.ops = &ls_pcie_host_ops,
 };

 static const struct of_device_id ls_pcie_of_match[] = {
 	{ .compatible = "fsl,ls1021a-pcie", .data = &ls1021_drvdata },
 	{ .compatible = "fsl,ls1043a-pcie", .data = &ls1043_drvdata },
 	{ .compatible = "fsl,ls2080a-pcie", .data = &ls2080_drvdata },
 	{ .compatible = "fsl,ls2085a-pcie", .data = &ls2080_drvdata },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, ls_pcie_of_match);

 static int __init ls_add_pcie_port(struct pcie_port *pp,
 				   struct platform_device *pdev)
 {
 	int ret;
 	struct ls_pcie *pcie = to_ls_pcie(pp);

 	pp->dev = &pdev->dev;
 	pp->dbi_base = pcie->dbi;
 	pp->ops = pcie->drvdata->ops;

 	ret = dw_pcie_host_init(pp);
 	if (ret) {
 		dev_err(pp->dev, "failed to initialize host\n");
 		return ret;
 	}

 	return 0;
 }

 static int __init ls_pcie_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *match;
 	struct ls_pcie *pcie;
 	struct resource *dbi_base;
 	int ret;

 	match = of_match_device(ls_pcie_of_match, &pdev->dev);
 	if (!match)
 		return -ENODEV;

 	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
 	if (!pcie)
 		return -ENOMEM;

 	dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
 	pcie->dbi = devm_ioremap_resource(&pdev->dev, dbi_base);
 	if (IS_ERR(pcie->dbi)) {
 		dev_err(&pdev->dev, "missing *regs* space\n");
 		return PTR_ERR(pcie->dbi);
 	}

 	pcie->drvdata = match->data;
 	pcie->lut = pcie->dbi + pcie->drvdata->lut_offset;

 	if (!ls_pcie_is_bridge(pcie))
 		return -ENODEV;

 	ret = ls_add_pcie_port(&pcie->pp, pdev);
 	if (ret < 0)
 		return ret;

 	platform_set_drvdata(pdev, pcie);

 	return 0;
 }

 static struct platform_driver ls_pcie_driver = {
 	.driver = {
 		.name = "layerscape-pcie",
 		.of_match_table = ls_pcie_of_match,
 	},
 };

 module_platform_driver_probe(ls_pcie_driver, ls_pcie_probe);

 MODULE_AUTHOR("Minghuan Lian <Minghuan.Lian@freescale.com>");
 MODULE_DESCRIPTION("Freescale Layerscape PCIe host controller driver");
 MODULE_LICENSE("GPL v2");
	/*
	* PCIe host controller driver for Freescale Layerscape SoCs
	*
	* Copyright (C) 2014 Freescale Semiconductor.
	*
	* Author: Minghuan Lian <Minghuan.Lian@freescale.com>
	*
	* 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/kernel.h>
	#include <linux/interrupt.h>
	#include <linux/module.h>
	#include <linux/of_pci.h>
	#include <linux/of_platform.h>
	#include <linux/of_irq.h>
	#include <linux/of_address.h>
	#include <linux/pci.h>
	#include <linux/platform_device.h>
	#include <linux/resource.h>
	#include <linux/mfd/syscon.h>
	#include <linux/regmap.h>

	#include "pcie-designware.h"

	/* PEX1/2 Misc Ports Status Register */
	#define SCFG_PEXMSCPORTSR(pex_idx) (0x94 + (pex_idx) * 4)
	#define LTSSM_STATE_SHIFT 20
	#define LTSSM_STATE_MASK 0x3f
	#define LTSSM_PCIE_L0 0x11 /* L0 state */

	/* PEX Internal Configuration Registers */
	#define PCIE_STRFMR1 0x71c /* Symbol Timer & Filter Mask Register1 */
	#define PCIE_DBI_RO_WR_EN 0x8bc /* DBI Read-Only Write Enable Register */

	/* PEX LUT registers */
	#define PCIE_LUT_DBG 0x7FC /* PEX LUT Debug Register */

	struct ls_pcie_drvdata {
	u32 lut_offset;
	u32 ltssm_shift;
	struct pcie_host_ops *ops;
	};

	struct ls_pcie {
	void __iomem *dbi;
	void __iomem *lut;
	struct regmap *scfg;
	struct pcie_port pp;
	const struct ls_pcie_drvdata *drvdata;
	int index;
	};

	#define to_ls_pcie(x) container_of(x, struct ls_pcie, pp)

	static bool ls_pcie_is_bridge(struct ls_pcie *pcie)
	{
	u32 header_type;

	header_type = ioread8(pcie->dbi + PCI_HEADER_TYPE);
	header_type &= 0x7f;

	return header_type == PCI_HEADER_TYPE_BRIDGE;
	}

	/* Clear multi-function bit */
	static void ls_pcie_clear_multifunction(struct ls_pcie *pcie)
	{
	iowrite8(PCI_HEADER_TYPE_BRIDGE, pcie->dbi + PCI_HEADER_TYPE);
	}

	/* Fix class value */
	static void ls_pcie_fix_class(struct ls_pcie *pcie)
	{
	iowrite16(PCI_CLASS_BRIDGE_PCI, pcie->dbi + PCI_CLASS_DEVICE);
	}

	/* Drop MSG TLP except for Vendor MSG */
	static void ls_pcie_drop_msg_tlp(struct ls_pcie *pcie)
	{
	u32 val;

	val = ioread32(pcie->dbi + PCIE_STRFMR1);
	val &= 0xDFFFFFFF;
	iowrite32(val, pcie->dbi + PCIE_STRFMR1);
	}

	static int ls1021_pcie_link_up(struct pcie_port *pp)
	{
	u32 state;
	struct ls_pcie *pcie = to_ls_pcie(pp);

	if (!pcie->scfg)
	return 0;

	regmap_read(pcie->scfg, SCFG_PEXMSCPORTSR(pcie->index), &state);
	state = (state >> LTSSM_STATE_SHIFT) & LTSSM_STATE_MASK;

	if (state < LTSSM_PCIE_L0)
	return 0;

	return 1;
	}

	static void ls1021_pcie_host_init(struct pcie_port *pp)
	{
	struct ls_pcie *pcie = to_ls_pcie(pp);
	u32 index[2];

	pcie->scfg = syscon_regmap_lookup_by_phandle(pp->dev->of_node,
	"fsl,pcie-scfg");
	if (IS_ERR(pcie->scfg)) {
	dev_err(pp->dev, "No syscfg phandle specified\n");
	pcie->scfg = NULL;
	return;
	}

	if (of_property_read_u32_array(pp->dev->of_node,
	"fsl,pcie-scfg", index, 2)) {
	pcie->scfg = NULL;
	return;
	}
	pcie->index = index[1];

	dw_pcie_setup_rc(pp);

	ls_pcie_drop_msg_tlp(pcie);
	}

	static int ls_pcie_link_up(struct pcie_port *pp)
	{
	struct ls_pcie *pcie = to_ls_pcie(pp);
	u32 state;

	state = (ioread32(pcie->lut + PCIE_LUT_DBG) >>
	pcie->drvdata->ltssm_shift) &
	LTSSM_STATE_MASK;

	if (state < LTSSM_PCIE_L0)
	return 0;

	return 1;
	}

	static void ls_pcie_host_init(struct pcie_port *pp)
	{
	struct ls_pcie *pcie = to_ls_pcie(pp);

	iowrite32(1, pcie->dbi + PCIE_DBI_RO_WR_EN);
	ls_pcie_fix_class(pcie);
	ls_pcie_clear_multifunction(pcie);
	ls_pcie_drop_msg_tlp(pcie);
	iowrite32(0, pcie->dbi + PCIE_DBI_RO_WR_EN);
	}

	static int ls_pcie_msi_host_init(struct pcie_port *pp,
	struct msi_controller *chip)
	{
	struct device_node *msi_node;
	struct device_node *np = pp->dev->of_node;

	/*
	* The MSI domain is set by the generic of_msi_configure(). This
	* .msi_host_init() function keeps us from doing the default MSI
	* domain setup in dw_pcie_host_init() and also enforces the
	* requirement that "msi-parent" exists.
	*/
	msi_node = of_parse_phandle(np, "msi-parent", 0);
	if (!msi_node) {
	dev_err(pp->dev, "failed to find msi-parent\n");
	return -EINVAL;
	}

	return 0;
	}

	static struct pcie_host_ops ls1021_pcie_host_ops = {
	.link_up = ls1021_pcie_link_up,
	.host_init = ls1021_pcie_host_init,
	.msi_host_init = ls_pcie_msi_host_init,
	};

	static struct pcie_host_ops ls_pcie_host_ops = {
	.link_up = ls_pcie_link_up,
	.host_init = ls_pcie_host_init,
	.msi_host_init = ls_pcie_msi_host_init,
	};

	static struct ls_pcie_drvdata ls1021_drvdata = {
	.ops = &ls1021_pcie_host_ops,
	};

	static struct ls_pcie_drvdata ls1043_drvdata = {
	.lut_offset = 0x10000,
	.ltssm_shift = 24,
	.ops = &ls_pcie_host_ops,
	};

	static struct ls_pcie_drvdata ls2080_drvdata = {
	.lut_offset = 0x80000,
	.ltssm_shift = 0,
	.ops = &ls_pcie_host_ops,
	};

	static const struct of_device_id ls_pcie_of_match[] = {
	{ .compatible = "fsl,ls1021a-pcie", .data = &ls1021_drvdata },
	{ .compatible = "fsl,ls1043a-pcie", .data = &ls1043_drvdata },
	{ .compatible = "fsl,ls2080a-pcie", .data = &ls2080_drvdata },
	{ .compatible = "fsl,ls2085a-pcie", .data = &ls2080_drvdata },
	{ },
	};
	MODULE_DEVICE_TABLE(of, ls_pcie_of_match);

	static int __init ls_add_pcie_port(struct pcie_port *pp,
	struct platform_device *pdev)
	{
	int ret;
	struct ls_pcie *pcie = to_ls_pcie(pp);

	pp->dev = &pdev->dev;
	pp->dbi_base = pcie->dbi;
	pp->ops = pcie->drvdata->ops;

	ret = dw_pcie_host_init(pp);
	if (ret) {
	dev_err(pp->dev, "failed to initialize host\n");
	return ret;
	}

	return 0;
	}

	static int __init ls_pcie_probe(struct platform_device *pdev)
	{
	const struct of_device_id *match;
	struct ls_pcie *pcie;
	struct resource *dbi_base;
	int ret;

	match = of_match_device(ls_pcie_of_match, &pdev->dev);
	if (!match)
	return -ENODEV;

	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
	if (!pcie)
	return -ENOMEM;

	dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
	pcie->dbi = devm_ioremap_resource(&pdev->dev, dbi_base);
	if (IS_ERR(pcie->dbi)) {
	dev_err(&pdev->dev, "missing regs space\n");
	return PTR_ERR(pcie->dbi);
	}

	pcie->drvdata = match->data;
	pcie->lut = pcie->dbi + pcie->drvdata->lut_offset;

	if (!ls_pcie_is_bridge(pcie))
	return -ENODEV;

	ret = ls_add_pcie_port(&pcie->pp, pdev);
	if (ret < 0)
	return ret;

	platform_set_drvdata(pdev, pcie);

	return 0;
	}

	static struct platform_driver ls_pcie_driver = {
	.driver = {
	.name = "layerscape-pcie",
	.of_match_table = ls_pcie_of_match,
	},
	};

	module_platform_driver_probe(ls_pcie_driver, ls_pcie_probe);

	MODULE_AUTHOR("Minghuan Lian <Minghuan.Lian@freescale.com>");
	MODULE_DESCRIPTION("Freescale Layerscape PCIe host controller driver");
	MODULE_LICENSE("GPL v2");