text: /* Copyright (c) 2013-2016, The Linux Foundation. All rights reserved.
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 and
   * only version 2 as published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/device.h>
  #include <linux/platform_device.h>
  #include <linux/io.h>
  #include <linux/err.h>
  #include <linux/slab.h>
  #include <linux/of.h>
  #include <linux/of_coresight.h>
  #include <linux/of_device.h>
  #include <linux/coresight.h>
  
  #include "coresight-priv.h"
  
  #define fuse_writel(drvdata, val, off)	__raw_writel((val), drvdata->base + off)
  #define fuse_readl(drvdata, off)	__raw_readl(drvdata->base + off)
  
  #define OEM_CONFIG0		(0x000)
  #define OEM_CONFIG1		(0x004)
  #define FEATURE_CONFIG2		(0x000)
  
  #define CORESIGHT_FUSE_VERSION_V1		"arm,coresight-fuse"
  #define CORESIGHT_FUSE_VERSION_V2		"arm,coresight-fuse-v2"
  
  /* CoreSight FUSE V1 */
  #define ALL_DEBUG_DISABLE	BIT(21)
  #define APPS_DBGEN_DISABLE	BIT(0)
  #define APPS_NIDEN_DISABLE	BIT(1)
  #define APPS_SPIDEN_DISABLE	BIT(2)
  #define APPS_SPNIDEN_DISABLE	BIT(3)
  #define DAP_DBGEN_DISABLE	BIT(4)
  #define DAP_NIDEN_DISABLE	BIT(5)
  #define DAP_SPIDEN_DISABLE	BIT(6)
  #define DAP_SPNIDEN_DISABLE	BIT(7)
  #define DAP_DEVICEEN_DISABLE	BIT(8)
  
  /* CoreSight FUSE V2 */
  #define ALL_DEBUG_DISABLE_V2		BIT(0)
  #define APPS_DBGEN_DISABLE_V2		BIT(10)
  #define APPS_NIDEN_DISABLE_V2		BIT(11)
  #define APPS_SPIDEN_DISABLE_V2		BIT(12)
  #define APPS_SPNIDEN_DISABLE_V2	BIT(13)
  #define DAP_DBGEN_DISABLE_V2		BIT(14)
  #define DAP_NIDEN_DISABLE_V2		BIT(15)
  #define DAP_SPIDEN_DISABLE_V2		BIT(16)
  #define DAP_SPNIDEN_DISABLE_V2		BIT(17)
  #define DAP_DEVICEEN_DISABLE_V2	BIT(18)
  
  #define QPDI_SPMI_DISABLE	BIT(2)
  #define NIDNT_DISABLE	BIT(27)
  
  struct fuse_nidnt {
  	void __iomem        *base;
  };
  
  struct fuse_qpdi {
  	void __iomem		*base;
  };
  
  struct fuse_drvdata {
  	void __iomem		*base;
  	struct fuse_nidnt	*fuse_nidnt;
  	struct fuse_qpdi	*qpdi;
  	struct device		*dev;
  	struct coresight_device	*csdev;
  	bool			fuse_v2;
  };
  
  static struct fuse_drvdata *fusedrvdata;
  
  bool coresight_fuse_nidnt_access_disabled(void)
  {
  	struct fuse_drvdata *drvdata = fusedrvdata;
  	uint32_t nidnt_fuse;
  	bool ret;
  
  	if (!drvdata || !drvdata->fuse_nidnt)
  		return false;
  
  	nidnt_fuse = fuse_readl(drvdata->fuse_nidnt, 0);
  
  	dev_dbg(drvdata->dev, "nidnt_fuse: %lx\n", (unsigned long)nidnt_fuse);
  
  	if (nidnt_fuse & NIDNT_DISABLE)
  		ret = true;
  	else
  		ret = false;
  
  	if (ret)
  		dev_dbg(drvdata->dev, "coresight nidnt fuse disabled\n");
  
  	return ret;
  }
  EXPORT_SYMBOL(coresight_fuse_nidnt_access_disabled);
  
  bool coresight_fuse_access_disabled(void)
  {
  	struct fuse_drvdata *drvdata = fusedrvdata;
  	uint32_t config0, config1;
  	bool ret = false;
  
  	if (!drvdata)
  		return false;
  
  	config0 = fuse_readl(drvdata, OEM_CONFIG0);
  	config1 = fuse_readl(drvdata, OEM_CONFIG1);
  
  	dev_dbg(drvdata->dev, "config0: %lx\n", (unsigned long)config0);
  	dev_dbg(drvdata->dev, "config1: %lx\n", (unsigned long)config1);
  
  	if (drvdata->fuse_v2) {
  		if (config1 & ALL_DEBUG_DISABLE_V2)
  			ret = true;
  		else if (config1 & DAP_DBGEN_DISABLE_V2)
  			ret = true;
  		else if (config1 & DAP_NIDEN_DISABLE_V2)
  			ret = true;
  		else if (config1 & DAP_SPIDEN_DISABLE_V2)
  			ret = true;
  		else if (config1 & DAP_SPNIDEN_DISABLE_V2)
  			ret = true;
  		else if (config1 & DAP_DEVICEEN_DISABLE_V2)
  			ret = true;
  	} else {
  		if (config0 & ALL_DEBUG_DISABLE)
  			ret = true;
  		else if (config1 & DAP_DBGEN_DISABLE)
  			ret = true;
  		else if (config1 & DAP_NIDEN_DISABLE)
  			ret = true;
  		else if (config1 & DAP_SPIDEN_DISABLE)
  			ret = true;
  		else if (config1 & DAP_SPNIDEN_DISABLE)
  			ret = true;
  		else if (config1 & DAP_DEVICEEN_DISABLE)
  			ret = true;
  	}
  
  	if (ret)
  		dev_dbg(drvdata->dev, "coresight fuse disabled\n");
  
  	return ret;
  }
  EXPORT_SYMBOL(coresight_fuse_access_disabled);
  
  bool coresight_fuse_apps_access_disabled(void)
  {
  	struct fuse_drvdata *drvdata = fusedrvdata;
  	uint32_t config0, config1;
  	bool ret = false;
  
  	if (!drvdata)
  		return false;
  
  	config0 = fuse_readl(drvdata, OEM_CONFIG0);
  	config1 = fuse_readl(drvdata, OEM_CONFIG1);
  
  	dev_dbg(drvdata->dev, "apps config0: %lx\n", (unsigned long)config0);
  	dev_dbg(drvdata->dev, "apps config1: %lx\n", (unsigned long)config1);
  
  	if (drvdata->fuse_v2) {
  		if (config1 & ALL_DEBUG_DISABLE_V2)
  			ret = true;
  		else if (config1 & APPS_DBGEN_DISABLE_V2)
  			ret = true;
  		else if (config1 & APPS_NIDEN_DISABLE_V2)
  			ret = true;
  		else if (config1 & APPS_SPIDEN_DISABLE_V2)
  			ret = true;
  		else if (config1 & APPS_SPNIDEN_DISABLE_V2)
  			ret = true;
  		else if (config1 & DAP_DEVICEEN_DISABLE_V2)
  			ret = true;
  	} else {
  		if (config0 & ALL_DEBUG_DISABLE)
  			ret = true;
  		else if (config1 & APPS_DBGEN_DISABLE)
  			ret = true;
  		else if (config1 & APPS_NIDEN_DISABLE)
  			ret = true;
  		else if (config1 & APPS_SPIDEN_DISABLE)
  			ret = true;
  		else if (config1 & APPS_SPNIDEN_DISABLE)
  			ret = true;
  		else if (config1 & DAP_DEVICEEN_DISABLE)
  			ret = true;
  	}
  
  	if (ret)
  		dev_dbg(drvdata->dev, "apps fuse disabled\n");
  
  	return ret;
  }
  EXPORT_SYMBOL(coresight_fuse_apps_access_disabled);
  
  bool coresight_fuse_qpdi_access_disabled(void)
  {
  	struct fuse_drvdata *drvdata = fusedrvdata;
  	uint32_t config;
  
  	if (!drvdata || !drvdata->qpdi)
  		return false;
  
  	config = fuse_readl(drvdata->qpdi, FEATURE_CONFIG2);
  
  	dev_dbg(drvdata->dev, "qpdi config: %lx\n", (unsigned long)config);
  
  	if (config & QPDI_SPMI_DISABLE) {
  		dev_dbg(drvdata->dev, "qpdi fuse disabled\n");
  		return true;
  	} else {
  		return false;
  	}
  }
  EXPORT_SYMBOL(coresight_fuse_qpdi_access_disabled);
  
  static struct of_device_id fuse_match[] = {
  	{.compatible = CORESIGHT_FUSE_VERSION_V1 },
  	{.compatible = CORESIGHT_FUSE_VERSION_V2 },
  	{}
  };
  
  static int fuse_probe(struct platform_device *pdev)
  {
  	struct device *dev = &pdev->dev;
  	struct coresight_platform_data *pdata;
  	struct fuse_drvdata *drvdata;
  	struct resource *res;
  	struct coresight_desc *desc;
  	const struct of_device_id *match;
  
  	if (pdev->dev.of_node) {
  		pdata = of_get_coresight_platform_data(dev, pdev->dev.of_node);
  		if (IS_ERR(pdata))
  			return PTR_ERR(pdata);
  		pdev->dev.platform_data = pdata;
  	}
  
  	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
  	if (!drvdata)
  		return -ENOMEM;
  	drvdata->dev = &pdev->dev;
  	platform_set_drvdata(pdev, drvdata);
  
  	match = of_match_device(fuse_match, dev);
  	if (!match)
  		return -EINVAL;
  
  	if (!strcmp(match->compatible, CORESIGHT_FUSE_VERSION_V2))
  		drvdata->fuse_v2 = true;
  
  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fuse-base");
  	if (!res)
  		return -ENODEV;
  
  	drvdata->base = devm_ioremap(dev, res->start, resource_size(res));
  	if (!drvdata->base)
  		return -ENOMEM;
  
  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
  					   "qpdi-fuse-base");
  	if (res) {
  		drvdata->qpdi = devm_kzalloc(dev, sizeof(*drvdata->qpdi),
  					     GFP_KERNEL);
  		if (!drvdata->qpdi)
  			return -ENOMEM;
  
  		drvdata->qpdi->base = devm_ioremap(dev, res->start,
  						   resource_size(res));
  		if (!drvdata->qpdi->base)
  			return -ENOMEM;
  	} else {
  		dev_info(dev, "QPDI fuse not specified\n");
  	}
  
  	res = platform_get_resource_byname(pdev,
  					   IORESOURCE_MEM,
  					   "nidnt-fuse-base");
  	if (res) {
  		drvdata->fuse_nidnt = devm_kzalloc(dev,
  						   sizeof(*drvdata->fuse_nidnt),
  						   GFP_KERNEL);
  		if (!drvdata->fuse_nidnt)
  			return -ENOMEM;
  
  		drvdata->fuse_nidnt->base = devm_ioremap(dev, res->start,
  							 resource_size(res));
  		if (!drvdata->fuse_nidnt->base)
  			return -ENOMEM;
  	}
  
  	desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
  	if (!desc)
  		return -ENOMEM;
  	desc->type = CORESIGHT_DEV_TYPE_NONE;
  	desc->pdata = pdev->dev.platform_data;
  	desc->dev = &pdev->dev;
  	desc->owner = THIS_MODULE;
  	drvdata->csdev = coresight_register(desc);
  	if (IS_ERR(drvdata->csdev))
  		return PTR_ERR(drvdata->csdev);
  
  	/* Store the driver data pointer for use in exported functions */
  	fusedrvdata = drvdata;
  
  	dev_info(dev, "Fuse initialized\n");
  	return 0;
  }
  
  static int fuse_remove(struct platform_device *pdev)
  {
  	struct fuse_drvdata *drvdata = platform_get_drvdata(pdev);
  
  	coresight_unregister(drvdata->csdev);
  	return 0;
  }
  
  static struct platform_driver fuse_driver = {
  	.probe          = fuse_probe,
  	.remove         = fuse_remove,
  	.driver         = {
  		.name   = "coresight-fuse",
  		.owner	= THIS_MODULE,
  		.of_match_table = fuse_match,
  	},
  };
  
  static int __init fuse_init(void)
  {
  	return platform_driver_register(&fuse_driver);
  }
  module_init(fuse_init);
  
  static void __exit fuse_exit(void)
  {
  	platform_driver_unregister(&fuse_driver);
  }
  module_exit(fuse_exit);
  
  MODULE_LICENSE("GPL v2");
  MODULE_DESCRIPTION("CoreSight Fuse driver");
  