drivers/iommu/msm_iommu_dev-v2.c - kernel/msm - Gitiles

 /* Copyright (c) 2012-2013, 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.
  */

 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/io.h>
 #include <linux/clk.h>
 #include <linux/iommu.h>
 #include <linux/interrupt.h>
 #include <linux/err.h>
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>

 #include <mach/iommu_hw-v2.h>
 #include <mach/iommu.h>
 #include <mach/iommu_perfmon.h>

 static int msm_iommu_parse_bfb_settings(struct platform_device *pdev,
 				    struct msm_iommu_drvdata *drvdata)
 {
 	struct msm_iommu_bfb_settings *bfb_settings;
 	u32 nreg, nval;
 	int ret, i;

 	/*
 	 * It is not valid for a device to have the qcom,iommu-bfb-regs
 	 * property but not the qcom,iommu-bfb-data property, and vice versa.
 	 */
 	if (!of_get_property(pdev->dev.of_node, "qcom,iommu-bfb-regs", &nreg)) {
 		if (of_get_property(pdev->dev.of_node, "qcom,iommu-bfb-data",
 				    &nval))
 			return -EINVAL;
 		return 0;
 	}

 	if (!of_get_property(pdev->dev.of_node, "qcom,iommu-bfb-data", &nval))
 		return -EINVAL;

 	if (nreg >= sizeof(bfb_settings->regs))
 		return -EINVAL;

 	if (nval >= sizeof(bfb_settings->data))
 		return -EINVAL;

 	if (nval != nreg)
 		return -EINVAL;

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

 	ret = of_property_read_u32_array(pdev->dev.of_node,
 					 "qcom,iommu-bfb-regs",
 					 bfb_settings->regs,
 					 nreg / sizeof(*bfb_settings->regs));
 	if (ret)
 		return ret;

 	ret = of_property_read_u32_array(pdev->dev.of_node,
 					 "qcom,iommu-bfb-data",
 					 bfb_settings->data,
 					 nval / sizeof(*bfb_settings->data));
 	if (ret)
 		return ret;

 	bfb_settings->length = nreg / sizeof(*bfb_settings->regs);

 	for (i = 0; i < bfb_settings->length; i++)
 		if (bfb_settings->regs[i] < IMPLDEF_OFFSET ||
 		    bfb_settings->regs[i] >= IMPLDEF_OFFSET + IMPLDEF_LENGTH)
 			return -EINVAL;

 	drvdata->bfb_settings = bfb_settings;
 	return 0;
 }

 static int msm_iommu_parse_dt(struct platform_device *pdev,
 				struct msm_iommu_drvdata *drvdata)
 {
 	struct device_node *child;
 	int ret = 0;
 	struct resource *r;

 	drvdata->dev = &pdev->dev;
 	msm_iommu_add_drv(drvdata);

 	ret = msm_iommu_parse_bfb_settings(pdev, drvdata);
 	if (ret)
 		goto fail;

 	for_each_child_of_node(pdev->dev.of_node, child) {
 		drvdata->ncb++;
 		if (!of_platform_device_create(child, NULL, &pdev->dev))
 			pr_err("Failed to create %s device\n", child->name);
 	}

 	ret = of_property_read_string(pdev->dev.of_node, "label",
 				      &drvdata->name);
 	if (ret)
 		goto fail;

 	drvdata->sec_id = -1;
 	of_property_read_u32(pdev->dev.of_node, "qcom,iommu-secure-id",
 				&drvdata->sec_id);

 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "clk_base");
 	if (r) {
 		drvdata->clk_reg_virt = devm_ioremap(&pdev->dev, r->start,
 						     resource_size(r));
 		if (!drvdata->clk_reg_virt) {
 			pr_err("Failed to map 0x%x for iommu clk\n",
 				r->start);
 			ret = -ENOMEM;
 			goto fail;
 		}
 	}

 	return 0;
 fail:
 	return ret;
 }

 static int msm_iommu_pmon_parse_dt(struct platform_device *pdev,
 					struct iommu_info *pmon_info)
 {
 	int ret = 0;
 	int irq = platform_get_irq(pdev, 0);

 	if (irq > 0) {
 		pmon_info->evt_irq = platform_get_irq(pdev, 0);
 	} else {
 		pmon_info->evt_irq = -1;
 		ret = irq;
 	}
 	return ret;
 }

 static int __devinit msm_iommu_probe(struct platform_device *pdev)
 {
 	struct iommu_info *pmon_info;
 	struct msm_iommu_drvdata *drvdata;
 	struct resource *r;
 	int ret, needs_alt_core_clk;

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

 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "iommu_base");
 	if (!r)
 		return -EINVAL;

 	drvdata->base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
 	if (!drvdata->base)
 		return -ENOMEM;

 	drvdata->glb_base = drvdata->base;

 	drvdata->gdsc = devm_regulator_get(&pdev->dev, "vdd");
 	if (IS_ERR(drvdata->gdsc))
 		return -EINVAL;

 	drvdata->alt_gdsc = devm_regulator_get(&pdev->dev, "qcom,alt-vdd");
 	if (IS_ERR(drvdata->alt_gdsc))
 		drvdata->alt_gdsc = NULL;

 	drvdata->pclk = devm_clk_get(&pdev->dev, "iface_clk");
 	if (IS_ERR(drvdata->pclk))
 		return PTR_ERR(drvdata->pclk);

 	drvdata->clk = devm_clk_get(&pdev->dev, "core_clk");
 	if (IS_ERR(drvdata->clk))
 		return PTR_ERR(drvdata->clk);

 	needs_alt_core_clk = of_property_read_bool(pdev->dev.of_node,
 						   "qcom,needs-alt-core-clk");
 	if (needs_alt_core_clk) {
 		drvdata->aclk = devm_clk_get(&pdev->dev, "alt_core_clk");
 		if (IS_ERR(drvdata->aclk))
 			return PTR_ERR(drvdata->aclk);
 	}

 	if (clk_get_rate(drvdata->clk) == 0) {
 		ret = clk_round_rate(drvdata->clk, 1);
 		clk_set_rate(drvdata->clk, ret);
 	}

 	if (drvdata->aclk && clk_get_rate(drvdata->aclk) == 0) {
 		ret = clk_round_rate(drvdata->aclk, 1);
 		clk_set_rate(drvdata->aclk, ret);
 	}

 	ret = msm_iommu_parse_dt(pdev, drvdata);
 	if (ret)
 		return ret;

 	dev_info(&pdev->dev, "device %s mapped at %p, with %d ctx banks\n",
 		drvdata->name, drvdata->base, drvdata->ncb);

 	platform_set_drvdata(pdev, drvdata);

 	pmon_info = msm_iommu_pm_alloc(&pdev->dev);
 	if (pmon_info != NULL) {
 		ret = msm_iommu_pmon_parse_dt(pdev, pmon_info);
 		if (ret) {
 			msm_iommu_pm_free(&pdev->dev);
 			pr_info("%s: pmon not available.\n", drvdata->name);
 		} else {
 			pmon_info->base = drvdata->base;
 			pmon_info->ops = &iommu_access_ops;
 			pmon_info->iommu_name = drvdata->name;
 			ret = msm_iommu_pm_iommu_register(pmon_info);
 			if (ret) {
 				pr_err("%s iommu register fail\n",
 								drvdata->name);
 				msm_iommu_pm_free(&pdev->dev);
 			} else {
 				pr_debug("%s iommu registered for pmon\n",
 						pmon_info->iommu_name);
 			}
 		}
 	}
 	return 0;
 }

 static int __devexit msm_iommu_remove(struct platform_device *pdev)
 {
 	struct msm_iommu_drvdata *drv = NULL;

 	msm_iommu_pm_iommu_unregister(&pdev->dev);
 	msm_iommu_pm_free(&pdev->dev);

 	drv = platform_get_drvdata(pdev);
 	if (drv) {
 		msm_iommu_remove_drv(drv);
 		if (drv->clk)
 			clk_put(drv->clk);
 		clk_put(drv->pclk);
 		platform_set_drvdata(pdev, NULL);
 	}
 	return 0;
 }

 static int msm_iommu_ctx_parse_dt(struct platform_device *pdev,
 				struct msm_iommu_ctx_drvdata *ctx_drvdata)
 {
 	struct resource *r, rp;
 	int irq, ret;
 	u32 nsid;

 	irq = platform_get_irq(pdev, 0);
 	if (irq > 0) {
 		ret = request_threaded_irq(irq, NULL,
 				msm_iommu_fault_handler_v2,
 				IRQF_ONESHOT | IRQF_SHARED,
 				"msm_iommu_nonsecure_irq", pdev);
 		if (ret) {
 			pr_err("Request IRQ %d failed with ret=%d\n", irq, ret);
 			return ret;
 		}
 	}

 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!r)
 		return -EINVAL;

 	ret = of_address_to_resource(pdev->dev.parent->of_node, 0, &rp);
 	if (ret)
 		return -EINVAL;

 	/* Calculate the context bank number using the base addresses. The
 	 * first 8 pages belong to the global address space which is followed
 	 * by the context banks, hence subtract by 8 to get the context bank
 	 * number.
 	 */
 	ctx_drvdata->num = ((r->start - rp.start) >> CTX_SHIFT) - 8;

 	if (of_property_read_string(pdev->dev.of_node, "label",
 					&ctx_drvdata->name))
 		ctx_drvdata->name = dev_name(&pdev->dev);

 	if (!of_get_property(pdev->dev.of_node, "qcom,iommu-ctx-sids", &nsid))
 		return -EINVAL;

 	if (nsid >= sizeof(ctx_drvdata->sids))
 		return -EINVAL;

 	if (of_property_read_u32_array(pdev->dev.of_node, "qcom,iommu-ctx-sids",
 				       ctx_drvdata->sids,
 				       nsid / sizeof(*ctx_drvdata->sids))) {
 		return -EINVAL;
 	}
 	ctx_drvdata->nsid = nsid;

 	ctx_drvdata->secure_context = of_property_read_bool(pdev->dev.of_node,
 							"qcom,secure-context");
 	ctx_drvdata->asid = -1;
 	return 0;
 }

 static int __devinit msm_iommu_ctx_probe(struct platform_device *pdev)
 {
 	struct msm_iommu_ctx_drvdata *ctx_drvdata = NULL;
 	int ret;

 	if (!pdev->dev.parent)
 		return -EINVAL;

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

 	ctx_drvdata->pdev = pdev;
 	INIT_LIST_HEAD(&ctx_drvdata->attached_elm);
 	platform_set_drvdata(pdev, ctx_drvdata);

 	ret = msm_iommu_ctx_parse_dt(pdev, ctx_drvdata);
 	if (!ret)
 		dev_info(&pdev->dev, "context %s using bank %d\n",
 			 ctx_drvdata->name, ctx_drvdata->num);

 	return ret;
 }

 static int __devexit msm_iommu_ctx_remove(struct platform_device *pdev)
 {
 	platform_set_drvdata(pdev, NULL);
 	return 0;
 }

 static struct of_device_id msm_iommu_match_table[] = {
 	{ .compatible = "qcom,msm-smmu-v2", },
 	{}
 };

 static struct platform_driver msm_iommu_driver = {
 	.driver = {
 		.name	= "msm_iommu_v2",
 		.of_match_table = msm_iommu_match_table,
 	},
 	.probe		= msm_iommu_probe,
 	.remove		= __devexit_p(msm_iommu_remove),
 };

 static struct of_device_id msm_iommu_ctx_match_table[] = {
 	{ .name = "qcom,iommu-ctx", },
 	{}
 };

 static struct platform_driver msm_iommu_ctx_driver = {
 	.driver = {
 		.name	= "msm_iommu_ctx_v2",
 		.of_match_table = msm_iommu_ctx_match_table,
 	},
 	.probe		= msm_iommu_ctx_probe,
 	.remove		= __devexit_p(msm_iommu_ctx_remove),
 };

 static int __init msm_iommu_driver_init(void)
 {
 	int ret;

 	ret = platform_driver_register(&msm_iommu_driver);
 	if (ret != 0) {
 		pr_err("Failed to register IOMMU driver\n");
 		goto error;
 	}

 	ret = platform_driver_register(&msm_iommu_ctx_driver);
 	if (ret != 0) {
 		pr_err("Failed to register IOMMU context driver\n");
 		goto error;
 	}

 error:
 	return ret;
 }

 static void __exit msm_iommu_driver_exit(void)
 {
 	platform_driver_unregister(&msm_iommu_ctx_driver);
 	platform_driver_unregister(&msm_iommu_driver);
 }

 subsys_initcall(msm_iommu_driver_init);
 module_exit(msm_iommu_driver_exit);

 MODULE_LICENSE("GPL v2");
	/* Copyright (c) 2012-2013, 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.
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/io.h>
	#include <linux/clk.h>
	#include <linux/iommu.h>
	#include <linux/interrupt.h>
	#include <linux/err.h>
	#include <linux/slab.h>
	#include <linux/of.h>
	#include <linux/of_address.h>
	#include <linux/of_device.h>

	#include <mach/iommu_hw-v2.h>
	#include <mach/iommu.h>
	#include <mach/iommu_perfmon.h>

	static int msm_iommu_parse_bfb_settings(struct platform_device *pdev,
	struct msm_iommu_drvdata *drvdata)
	{
	struct msm_iommu_bfb_settings *bfb_settings;
	u32 nreg, nval;
	int ret, i;

	/*
	* It is not valid for a device to have the qcom,iommu-bfb-regs
	* property but not the qcom,iommu-bfb-data property, and vice versa.
	*/
	if (!of_get_property(pdev->dev.of_node, "qcom,iommu-bfb-regs", &nreg)) {
	if (of_get_property(pdev->dev.of_node, "qcom,iommu-bfb-data",
	&nval))
	return -EINVAL;
	return 0;
	}

	if (!of_get_property(pdev->dev.of_node, "qcom,iommu-bfb-data", &nval))
	return -EINVAL;

	if (nreg >= sizeof(bfb_settings->regs))
	return -EINVAL;

	if (nval >= sizeof(bfb_settings->data))
	return -EINVAL;

	if (nval != nreg)
	return -EINVAL;

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

	ret = of_property_read_u32_array(pdev->dev.of_node,
	"qcom,iommu-bfb-regs",
	bfb_settings->regs,
	nreg / sizeof(*bfb_settings->regs));
	if (ret)
	return ret;

	ret = of_property_read_u32_array(pdev->dev.of_node,
	"qcom,iommu-bfb-data",
	bfb_settings->data,
	nval / sizeof(*bfb_settings->data));
	if (ret)
	return ret;

	bfb_settings->length = nreg / sizeof(*bfb_settings->regs);

	for (i = 0; i < bfb_settings->length; i++)
	if (bfb_settings->regs[i] < IMPLDEF_OFFSET \|\|
	bfb_settings->regs[i] >= IMPLDEF_OFFSET + IMPLDEF_LENGTH)
	return -EINVAL;

	drvdata->bfb_settings = bfb_settings;
	return 0;
	}

	static int msm_iommu_parse_dt(struct platform_device *pdev,
	struct msm_iommu_drvdata *drvdata)
	{
	struct device_node *child;
	int ret = 0;
	struct resource *r;

	drvdata->dev = &pdev->dev;
	msm_iommu_add_drv(drvdata);

	ret = msm_iommu_parse_bfb_settings(pdev, drvdata);
	if (ret)
	goto fail;

	for_each_child_of_node(pdev->dev.of_node, child) {
	drvdata->ncb++;
	if (!of_platform_device_create(child, NULL, &pdev->dev))
	pr_err("Failed to create %s device\n", child->name);
	}

	ret = of_property_read_string(pdev->dev.of_node, "label",
	&drvdata->name);
	if (ret)
	goto fail;

	drvdata->sec_id = -1;
	of_property_read_u32(pdev->dev.of_node, "qcom,iommu-secure-id",
	&drvdata->sec_id);

	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "clk_base");
	if (r) {
	drvdata->clk_reg_virt = devm_ioremap(&pdev->dev, r->start,
	resource_size(r));
	if (!drvdata->clk_reg_virt) {
	pr_err("Failed to map 0x%x for iommu clk\n",
	r->start);
	ret = -ENOMEM;
	goto fail;
	}
	}

	return 0;
	fail:
	return ret;
	}

	static int msm_iommu_pmon_parse_dt(struct platform_device *pdev,
	struct iommu_info *pmon_info)
	{
	int ret = 0;
	int irq = platform_get_irq(pdev, 0);

	if (irq > 0) {
	pmon_info->evt_irq = platform_get_irq(pdev, 0);
	} else {
	pmon_info->evt_irq = -1;
	ret = irq;
	}
	return ret;
	}

	static int __devinit msm_iommu_probe(struct platform_device *pdev)
	{
	struct iommu_info *pmon_info;
	struct msm_iommu_drvdata *drvdata;
	struct resource *r;
	int ret, needs_alt_core_clk;

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

	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "iommu_base");
	if (!r)
	return -EINVAL;

	drvdata->base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
	if (!drvdata->base)
	return -ENOMEM;

	drvdata->glb_base = drvdata->base;

	drvdata->gdsc = devm_regulator_get(&pdev->dev, "vdd");
	if (IS_ERR(drvdata->gdsc))
	return -EINVAL;

	drvdata->alt_gdsc = devm_regulator_get(&pdev->dev, "qcom,alt-vdd");
	if (IS_ERR(drvdata->alt_gdsc))
	drvdata->alt_gdsc = NULL;

	drvdata->pclk = devm_clk_get(&pdev->dev, "iface_clk");
	if (IS_ERR(drvdata->pclk))
	return PTR_ERR(drvdata->pclk);

	drvdata->clk = devm_clk_get(&pdev->dev, "core_clk");
	if (IS_ERR(drvdata->clk))
	return PTR_ERR(drvdata->clk);

	needs_alt_core_clk = of_property_read_bool(pdev->dev.of_node,
	"qcom,needs-alt-core-clk");
	if (needs_alt_core_clk) {
	drvdata->aclk = devm_clk_get(&pdev->dev, "alt_core_clk");
	if (IS_ERR(drvdata->aclk))
	return PTR_ERR(drvdata->aclk);
	}

	if (clk_get_rate(drvdata->clk) == 0) {
	ret = clk_round_rate(drvdata->clk, 1);
	clk_set_rate(drvdata->clk, ret);
	}

	if (drvdata->aclk && clk_get_rate(drvdata->aclk) == 0) {
	ret = clk_round_rate(drvdata->aclk, 1);
	clk_set_rate(drvdata->aclk, ret);
	}

	ret = msm_iommu_parse_dt(pdev, drvdata);
	if (ret)
	return ret;

	dev_info(&pdev->dev, "device %s mapped at %p, with %d ctx banks\n",
	drvdata->name, drvdata->base, drvdata->ncb);

	platform_set_drvdata(pdev, drvdata);

	pmon_info = msm_iommu_pm_alloc(&pdev->dev);
	if (pmon_info != NULL) {
	ret = msm_iommu_pmon_parse_dt(pdev, pmon_info);
	if (ret) {
	msm_iommu_pm_free(&pdev->dev);
	pr_info("%s: pmon not available.\n", drvdata->name);
	} else {
	pmon_info->base = drvdata->base;
	pmon_info->ops = &iommu_access_ops;
	pmon_info->iommu_name = drvdata->name;
	ret = msm_iommu_pm_iommu_register(pmon_info);
	if (ret) {
	pr_err("%s iommu register fail\n",
	drvdata->name);
	msm_iommu_pm_free(&pdev->dev);
	} else {
	pr_debug("%s iommu registered for pmon\n",
	pmon_info->iommu_name);
	}
	}
	}
	return 0;
	}

	static int __devexit msm_iommu_remove(struct platform_device *pdev)
	{
	struct msm_iommu_drvdata *drv = NULL;

	msm_iommu_pm_iommu_unregister(&pdev->dev);
	msm_iommu_pm_free(&pdev->dev);

	drv = platform_get_drvdata(pdev);
	if (drv) {
	msm_iommu_remove_drv(drv);
	if (drv->clk)
	clk_put(drv->clk);
	clk_put(drv->pclk);
	platform_set_drvdata(pdev, NULL);
	}
	return 0;
	}

	static int msm_iommu_ctx_parse_dt(struct platform_device *pdev,
	struct msm_iommu_ctx_drvdata *ctx_drvdata)
	{
	struct resource *r, rp;
	int irq, ret;
	u32 nsid;

	irq = platform_get_irq(pdev, 0);
	if (irq > 0) {
	ret = request_threaded_irq(irq, NULL,
	msm_iommu_fault_handler_v2,
	IRQF_ONESHOT \| IRQF_SHARED,
	"msm_iommu_nonsecure_irq", pdev);
	if (ret) {
	pr_err("Request IRQ %d failed with ret=%d\n", irq, ret);
	return ret;
	}
	}

	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!r)
	return -EINVAL;

	ret = of_address_to_resource(pdev->dev.parent->of_node, 0, &rp);
	if (ret)
	return -EINVAL;

	/* Calculate the context bank number using the base addresses. The
	* first 8 pages belong to the global address space which is followed
	* by the context banks, hence subtract by 8 to get the context bank
	* number.
	*/
	ctx_drvdata->num = ((r->start - rp.start) >> CTX_SHIFT) - 8;

	if (of_property_read_string(pdev->dev.of_node, "label",
	&ctx_drvdata->name))
	ctx_drvdata->name = dev_name(&pdev->dev);

	if (!of_get_property(pdev->dev.of_node, "qcom,iommu-ctx-sids", &nsid))
	return -EINVAL;

	if (nsid >= sizeof(ctx_drvdata->sids))
	return -EINVAL;

	if (of_property_read_u32_array(pdev->dev.of_node, "qcom,iommu-ctx-sids",
	ctx_drvdata->sids,
	nsid / sizeof(*ctx_drvdata->sids))) {
	return -EINVAL;
	}
	ctx_drvdata->nsid = nsid;

	ctx_drvdata->secure_context = of_property_read_bool(pdev->dev.of_node,
	"qcom,secure-context");
	ctx_drvdata->asid = -1;
	return 0;
	}

	static int __devinit msm_iommu_ctx_probe(struct platform_device *pdev)
	{
	struct msm_iommu_ctx_drvdata *ctx_drvdata = NULL;
	int ret;

	if (!pdev->dev.parent)
	return -EINVAL;

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

	ctx_drvdata->pdev = pdev;
	INIT_LIST_HEAD(&ctx_drvdata->attached_elm);
	platform_set_drvdata(pdev, ctx_drvdata);

	ret = msm_iommu_ctx_parse_dt(pdev, ctx_drvdata);
	if (!ret)
	dev_info(&pdev->dev, "context %s using bank %d\n",
	ctx_drvdata->name, ctx_drvdata->num);

	return ret;
	}

	static int __devexit msm_iommu_ctx_remove(struct platform_device *pdev)
	{
	platform_set_drvdata(pdev, NULL);
	return 0;
	}

	static struct of_device_id msm_iommu_match_table[] = {
	{ .compatible = "qcom,msm-smmu-v2", },
	{}
	};

	static struct platform_driver msm_iommu_driver = {
	.driver = {
	.name = "msm_iommu_v2",
	.of_match_table = msm_iommu_match_table,
	},
	.probe = msm_iommu_probe,
	.remove = __devexit_p(msm_iommu_remove),
	};

	static struct of_device_id msm_iommu_ctx_match_table[] = {
	{ .name = "qcom,iommu-ctx", },
	{}
	};

	static struct platform_driver msm_iommu_ctx_driver = {
	.driver = {
	.name = "msm_iommu_ctx_v2",
	.of_match_table = msm_iommu_ctx_match_table,
	},
	.probe = msm_iommu_ctx_probe,
	.remove = __devexit_p(msm_iommu_ctx_remove),
	};

	static int __init msm_iommu_driver_init(void)
	{
	int ret;

	ret = platform_driver_register(&msm_iommu_driver);
	if (ret != 0) {
	pr_err("Failed to register IOMMU driver\n");
	goto error;
	}

	ret = platform_driver_register(&msm_iommu_ctx_driver);
	if (ret != 0) {
	pr_err("Failed to register IOMMU context driver\n");
	goto error;
	}

	error:
	return ret;
	}

	static void __exit msm_iommu_driver_exit(void)
	{
	platform_driver_unregister(&msm_iommu_ctx_driver);
	platform_driver_unregister(&msm_iommu_driver);
	}

	subsys_initcall(msm_iommu_driver_init);
	module_exit(msm_iommu_driver_exit);

	MODULE_LICENSE("GPL v2");