iommu: msm: add snapshot of msm_iommu.c

/* Copyright (c) 2013-2014, 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/errno.h>

#include <linux/err.h>

#include <linux/list.h>

#include <linux/mutex.h>

#include <linux/platform_device.h>

#include <linux/export.h>

#include <linux/iommu.h>

#include <linux/qcom_iommu.h>

static DEFINE_MUTEX(iommu_list_lock);

static LIST_HEAD(iommu_list);

#define MRC(reg, processor, op1, crn, crm, op2)				\

__asm__ __volatile__ (							\

"   mrc   "   #processor "," #op1 ", %0,"  #crn "," #crm "," #op2 "\n"  \

: "=r" (reg))

#define RCP15_PRRR(reg)   MRC(reg, p15, 0, c10, c2, 0)

#define RCP15_NMRR(reg)   MRC(reg, p15, 0, c10, c2, 1)

#define RCP15_MAIR0(reg)   MRC(reg, p15, 0, c10, c2, 0)

#define RCP15_MAIR1(reg)   MRC(reg, p15, 0, c10, c2, 1)

/* These values come from proc-v7-2level.S */

#define PRRR_VALUE 0xff0a81a8

#define NMRR_VALUE 0x40e040e0

/* These values come from proc-v7-3level.S */

#define MAIR0_VALUE 0xeeaa4400

#define MAIR1_VALUE 0xff000004

static struct iommu_access_ops *iommu_access_ops;

struct bus_type msm_iommu_sec_bus_type = {

	.name = "msm_iommu_sec_bus",

};

void msm_set_iommu_access_ops(struct iommu_access_ops *ops)

{

	iommu_access_ops = ops;

}

struct iommu_access_ops *msm_get_iommu_access_ops()

{

	BUG_ON(iommu_access_ops == NULL);

	return iommu_access_ops;

}

EXPORT_SYMBOL(msm_get_iommu_access_ops);

void msm_iommu_add_drv(struct msm_iommu_drvdata *drv)

{

	mutex_lock(&iommu_list_lock);

	list_add(&drv->list, &iommu_list);

	mutex_unlock(&iommu_list_lock);

}

void msm_iommu_remove_drv(struct msm_iommu_drvdata *drv)

{

	mutex_lock(&iommu_list_lock);

	list_del(&drv->list);

	mutex_unlock(&iommu_list_lock);

}

static int find_iommu_ctx(struct device *dev, void *data)

{

	struct msm_iommu_ctx_drvdata *c;

	c = dev_get_drvdata(dev);

	if (!c || !c->name)

		return 0;

	return !strcmp(data, c->name);

}

static struct device *find_context(struct device *dev, const char *name)

{

	return device_find_child(dev, (void *)name, find_iommu_ctx);

}

struct device *msm_iommu_get_ctx(const char *ctx_name)

{

	struct msm_iommu_drvdata *drv;

	struct device *dev = NULL;

	mutex_lock(&iommu_list_lock);

	list_for_each_entry(drv, &iommu_list, list) {

		dev = find_context(drv->dev, ctx_name);

		if (dev)

			break;

	}

	mutex_unlock(&iommu_list_lock);

	put_device(dev);

	if (!dev || !dev_get_drvdata(dev)) {

		pr_debug("Could not find context <%s>\n", ctx_name);

		dev = ERR_PTR(-EPROBE_DEFER);

	}

	return dev;

}

EXPORT_SYMBOL(msm_iommu_get_ctx);

#ifdef CONFIG_ARM

#ifdef CONFIG_IOMMU_LPAE

#ifdef CONFIG_ARM_LPAE

/*

 * If CONFIG_ARM_LPAE AND CONFIG_IOMMU_LPAE are enabled we can use the MAIR

 * register directly

 */

u32 msm_iommu_get_mair0(void)

{

	unsigned int mair0;

	RCP15_MAIR0(mair0);

	return mair0;

}

u32 msm_iommu_get_mair1(void)

{

	unsigned int mair1;

	RCP15_MAIR1(mair1);

	return mair1;

}

#else

/*

 * However, If CONFIG_ARM_LPAE is not enabled but CONFIG_IOMMU_LPAE is enabled

 * we'll just use the hard coded values directly..

 */

u32 msm_iommu_get_mair0(void)

{

	return MAIR0_VALUE;

}

u32 msm_iommu_get_mair1(void)

{

	return MAIR1_VALUE;

}

#endif

#else

#ifdef CONFIG_ARM_LPAE

/*

 * If CONFIG_ARM_LPAE is enabled AND CONFIG_IOMMU_LPAE is disabled

 * we must use the hardcoded values.

 */

u32 msm_iommu_get_prrr(void)

{

	return PRRR_VALUE;

}

u32 msm_iommu_get_nmrr(void)

{

	return NMRR_VALUE;

}

#else

/*

 * If both CONFIG_ARM_LPAE AND CONFIG_IOMMU_LPAE are disabled

 * we can use the registers directly.

 */

#define RCP15_PRRR(reg)		MRC(reg, p15, 0, c10, c2, 0)

#define RCP15_NMRR(reg)		MRC(reg, p15, 0, c10, c2, 1)

u32 msm_iommu_get_prrr(void)

{

	u32 prrr;

	RCP15_PRRR(prrr);

	return prrr;

}

u32 msm_iommu_get_nmrr(void)

{

	u32 nmrr;

	RCP15_NMRR(nmrr);

	return nmrr;

}

#endif

#endif

#endif

#ifdef CONFIG_ARM64

u32 msm_iommu_get_prrr(void)

{

	return PRRR_VALUE;

}

u32 msm_iommu_get_nmrr(void)

{

	return NMRR_VALUE;

}

#endif