path: root/drivers/iommu/omap-iommu.c

/*
 * omap iommu: tlb and pagetable primitives
 *
 * Copyright (C) 2008-2010 Nokia Corporation
 *
 * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>,
 *		Paul Mundt and Toshihiro Kobayashi
 *
 * 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/err.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/iommu.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>

#include <asm/cacheflush.h>

#include <plat/iommu.h>

#include <plat/iopgtable.h>

#define for_each_iotlb_cr(obj, n, __i, cr)				\
	for (__i = 0;							\
	     (__i < (n)) && (cr = __iotlb_read_cr((obj), __i), true);	\
	     __i++)

/* bitmap of the page sizes currently supported */
#define OMAP_IOMMU_PGSIZES	(SZ_4K | SZ_64K | SZ_1M | SZ_16M)

/**
 * struct omap_iommu_domain - omap iommu domain
 * @pgtable:	the page table
 * @iommu_dev:	an omap iommu device attached to this domain. only a single
 *		iommu device can be attached for now.
 * @lock:	domain lock, should be taken when attaching/detaching
 */
struct omap_iommu_domain {
	u32 *pgtable;
	struct omap_iommu *iommu_dev;
	spinlock_t lock;
};

/* accommodate the difference between omap1 and omap2/3 */
static const struct iommu_functions *arch_iommu;

static struct platform_driver omap_iommu_driver;
static struct kmem_cache *iopte_cachep;

/**
 * omap_install_iommu_arch - Install archtecure specific iommu functions
 * @ops:	a pointer to architecture specific iommu functions
 *
 * There are several kind of iommu algorithm(tlb, pagetable) among
 * omap series. This interface installs such an iommu algorighm.
 **/
int omap_install_iommu_arch(const struct iommu_functions *ops)
{
	if (arch_iommu)
		return -EBUSY;

	arch_iommu = ops;
	return 0;
}
EXPORT_SYMBOL_GPL(omap_install_iommu_arch);

/**
 * omap_uninstall_iommu_arch - Uninstall archtecure specific iommu functions
 * @ops:	a pointer to architecture specific iommu functions
 *
 * This interface uninstalls the iommu algorighm installed previously.
 **/
void omap_uninstall_iommu_arch(const struct iommu_functions *ops)
{
	if (arch_iommu != ops)
		pr_err("%s: not your arch\n", __func__);

	arch_iommu = NULL;
}
EXPORT_SYMBOL_GPL(omap_uninstall_iommu_arch);

/**
 * omap_iommu_save_ctx - Save registers for pm off-mode support
 * @obj:	target iommu
 **/
void omap_iommu_save_ctx(struct omap_iommu *obj)
{
	arch_iommu->save_ctx(obj);
}
EXPORT_SYMBOL_GPL(omap_iommu_save_ctx);

/**
 * omap_iommu_restore_ctx - Restore registers for pm off-mode support
 * @obj:	target iommu
 **/
void omap_iommu_restore_ctx(struct omap_iommu *obj)
{
	arch_iommu->restore_ctx(obj);
}
EXPORT_SYMBOL_GPL(omap_iommu_restore_ctx);

/**
 * omap_iommu_arch_version - Return running iommu arch version
 **/
u32 omap_iommu_arch_version(void)
{
	return arch_iommu->version;
}
EXPORT_SYMBOL_GPL(omap_iommu_arch_version);

static int iommu_enable(struct omap_iommu *obj)
{
	int err;

	if (!obj)
		return -EINVAL;

	if (!arch_iommu)
		return -ENODEV;

	clk_enable(obj->clk);

	err = arch_iommu->enable(obj);

	clk_disable(obj->clk);
	return err;
}

static void iommu_disable(struct omap_iommu *obj)
{
	if (!obj)
		return;

	clk_enable(obj->clk);

	arch_iommu->disable(obj);

	clk_disable(obj->clk);
}

/*
 *	TLB operations
 */
void omap_iotlb_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e)
{
	BUG_ON(!cr || !e);

	arch_iommu