include/linux/i2c-pxa.h


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#ifndef _LINUX_I2C_ALGO_PXA_H
#define _LINUX_I2C_ALGO_PXA_H

struct i2c_eeprom_emu_watcher {
	void (*write)(void *, unsigned int addr, unsigned char newval);
};

struct i2c_eeprom_emu_watch {
	struct list_head node;
	unsigned int start;
	unsigned int end;
	struct i2c_eeprom_emu_watcher *ops;
	void *data;
};

#define I2C_EEPROM_EMU_SIZE (256)

struct i2c_eeprom_emu {
	unsigned int size;
	unsigned int ptr;
	unsigned int seen_start;
	struct list_head watch;

	unsigned char bytes[I2C_EEPROM_EMU_SIZE];
};

typedef enum i2c_slave_event_e {
	I2C_SLAVE_EVENT_START_READ,
	I2C_SLAVE_EVENT_START_WRITE,
	I2C_SLAVE_EVENT_STOP
} i2c_slave_event_t;

struct i2c_slave_client {
	void *data;
	void (*event)(void *ptr, i2c_slave_event_t event);
	int  (*read) (void *ptr);
	void (*write)(void *ptr, unsigned int val);
};

extern int i2c_eeprom_emu_addwatcher(struct i2c_eeprom_emu *, void *data,
				     unsigned int addr, unsigned int size,
				     struct i2c_eeprom_emu_watcher *);

extern void i2c_eeprom_emu_delwatcher(struct i2c_eeprom_emu *, void *data, struct i2c_eeprom_emu_watcher *watcher);

extern struct i2c_eeprom_emu *i2c_pxa_get_eeprom(void);

#endif /* _LINUX_I2C_ALGO_PXA_H */
/*
 * 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.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright (C) 2013 Freescale Semiconductor, Inc.
 * Author: Varun Sethi <varun.sethi@freescale.com>
 *
 */

#define pr_fmt(fmt)    "fsl-pamu-domain: %s: " fmt, __func__

#include "fsl_pamu_domain.h"

#include <sysdev/fsl_pci.h>

/*
 * Global spinlock that needs to be held while
 * configuring PAMU.
 */
static DEFINE_SPINLOCK(iommu_lock);

static struct kmem_cache *fsl_pamu_domain_cache;
static struct kmem_cache *iommu_devinfo_cache;
static DEFINE_SPINLOCK(device_domain_lock);

static struct fsl_dma_domain *to_fsl_dma_domain(struct iommu_domain *dom)
{
	return container_of(dom, struct fsl_dma_domain, iommu_domain);
}

static int __init iommu_init_mempool(void)
{
	fsl_pamu_domain_cache = kmem_cache_create("fsl_pamu_domain",
						  sizeof(struct fsl_dma_domain),
						  0,
						  SLAB_HWCACHE_ALIGN,
						  NULL);
	if (!fsl_pamu_domain_cache) {
		pr_debug("Couldn't create fsl iommu_domain cache\n");
		return -ENOMEM;
	}

	iommu_devinfo_cache = kmem_cache_create("iommu_devinfo",
						sizeof(struct device_domain_info),
						0,
						SLAB_HWCACHE_ALIGN,
						NULL);
	if (!iommu_devinfo_cache) {
		pr_debug("Couldn't create devinfo cache\n");
		kmem_cache_destroy(fsl_pamu_domain_cache);
		return -ENOMEM;
	}

	return 0;
}

static phys_addr_t get_phys_addr(struct fsl_dma_domain *dma_domain, dma_addr_t iova)
{
	u32 win_cnt = dma_domain->win_cnt;
	struct dma_window *win_ptr = &dma_domain->win_arr[0];
	struct iommu_domain_geometry *geom;

	geom = &dma_domain->iommu_domain.geometry;

	if (!win_cnt || !dma_domain->geom_size) {
		pr_debug("Number of windows/geometry not configured for the domain\n");
		return 0;
	}

	if (win_cnt > 1) {
		u64 subwin_size;
		dma_addr_t subwin_iova;
		u32 wnd;

		subwin_size = dma_domain->geom_size >> ilog2(win_cnt);
		subwin_iova = iova & ~(subwin_size - 1);
		wnd = (subwin_iova - geom->aperture_start) >> ilog2(subwin_size);
		win_ptr = &dma_domain->win_arr[wnd];
	}

	if (win_ptr->valid)
		return win_ptr->paddr + (iova & (win_ptr->size - 1));

	return 0;
}

static int map_subwins(int liodn, struct fsl_dma_domain *dma_domain)
{
	struct dma_window *sub_win_ptr = &dma_domain->win_arr[0];
	int i, ret;
	unsigned long rpn, flags;

	for (i = 0; i < dma_domain->win_cnt; i++) {
		if (sub_win_ptr[i].valid) {
			rpn = sub_win_ptr[i].paddr >> PAMU_PAGE_SHIFT;
			spin_lock_irqsave(&iommu_lock, flags);
			ret = pamu_config_spaace(liodn, dma_domain->win_cnt, i,
						 sub_win_ptr[i].size,
						 ~(u32)0,
						 rpn,
						 dma_domain->snoop_id,
						 dma_domain->stash_id,
						 (i > 0) ? 1 : 0,
						 sub_win_ptr[i].prot);
			spin_unlock_irqrestore(&iommu_lock, flags);
			if (ret) {
				pr_debug("SPAACE configuration failed for liodn %d\n",
					 liodn);
				return ret;
			}
		}
	}

	return ret;
}

static int map_win(int liodn, struct fsl_dma_domain *dma_domain)
{
	int ret;
	struct dma_window *wnd = &dma_domain->win_arr[0];
	phys_addr_t wnd_addr = dma_domain->iommu_domain.geometry.aperture_start;
	unsigned long flags;

	spin_lock_irqsave(&iommu_lock, flags);
	ret = pamu_config_ppaace(liodn, wnd_addr,
				 wnd->size,
				 ~(u32)0,
				 wnd->paddr >> PAMU_PAGE_SHIFT,
				 dma_domain->snoop_id, dma_domain->stash_id,
				 0, wnd->prot);
	spin_unlock_irqrestore(&iommu_lock, flags);
	if (ret)
		pr_debug("PAACE configuration failed for liodn %d\n", liodn);

	return ret;
}

/* Map the DMA window corresponding to the LIODN */
static int map_liodn(int liodn, struct fsl_dma_domain *dma_domain)
{
	if (dma_domain->win_cnt > 1)
		return map_subwins(liodn, dma_domain);
	else
		return map_win(liodn, dma_domain);
}

/* Update window/subwindow mapping for the LIODN */
static int update_liodn(int liodn, struct fsl_dma_domain *dma_domain, u32 wnd_nr)
{
	int ret;
	struct dma_window *wnd = &dma_domain->win_arr[wnd_nr];
	unsigned long flags;

	spin_lock_irqsave(&iommu_lock, flags);
	if (dma_domain->win_cnt > 1) {
		ret = pamu_config_spaace(liodn, dma_domain->win_cnt, wnd_nr,
					 wnd->size,
					 ~(u32)0,
					 wnd->paddr >> PAMU_PAGE_SHIFT,
					 dma_domain->snoop_id,
					 dma_domain->stash_id,
					 (wnd_nr > 0) ? 1 : 0,
					 wnd->prot);
		if (ret)
			pr_debug("Subwindow reconfiguration failed for liodn %d\n",
				 liodn);
	} else {
		phys_addr_t wnd_addr;

		wnd_addr = dma_domain->iommu_domain.geometry.aperture_start;

		ret = pamu_config_ppaace(liodn, wnd_addr,
					 wnd->size,
					 ~(u32)0,
					 wnd->paddr >> PAMU_PAGE_SHIFT,
					 dma_domain->snoop_id, dma_domain->stash_id,
					 0, wnd->prot);
		if (ret)
			pr_debug("Window reconfiguration failed for liodn %d\n",
				 liodn);
	}

	spin_unlock_irqrestore(&iommu_lock, flags);

	return ret;
}

static int update_liodn_stash(int liodn, struct fsl_dma_domain *dma_domain,
			      u32 val)
{
	int ret = 0, i;
	unsigned long flags;

	spin_lock_irqsave(&iommu_lock, flags);
	if (!dma_domain->win_arr) {
		pr_debug("Windows not configured, stash destination update failed for liodn %d\n",
			 liodn);
		spin_unlock_irqrestore(&iommu_lock, flags);
		return -EINVAL;
	}

	for (i = 0; i < dma_domain->win_cnt; i++) {
		ret = pamu_update_paace_stash(liodn, i, val);
		if (ret) {
			pr_debug("Failed to update SPAACE %d field for liodn %d\n ",
				 i, liodn);
			spin_unlock_irqrestore(&iommu_lock, flags);
			return ret;
		}
	}

	spin_unlock_irqrestore(&iommu_lock, flags);

	return ret;
}

/* Set the geometry parameters for a LIODN */
static int pamu_set_liodn(int liodn, struct device *dev,
			  struct fsl_dma_domain *dma_domain,
			  struct iommu_domain_geometry *geom_attr,
			  u32 win_cnt)
{
	phys_addr_t window_addr, window_size;
	phys_addr_t subwin_size;
	int ret = 0, i;
	u32 omi_index = ~(u32)0;
	unsigned long flags;

	/*
	 * Configure the omi_index at the geometry setup time.
	 * This is a static value which depends on the type of
	 * device and would not change thereafter.
	 */
	get_ome_index(&omi_index, dev);

	window_addr = geom_attr->aperture_start;
	window_size = dma_domain->geom_size;

	spin_lock_irqsave(&iommu_lock, flags);
	ret = pamu_disable_liodn(liodn);
	if (!ret)
		ret = pamu_config_ppaace(liodn, window_addr, window_size, omi_index,
					 0, dma_domain->snoop_id,
					 dma_domain->stash_id, win_cnt, 0);
	spin_unlock_irqrestore(&iommu_lock, flags);
	if (ret) {
		pr_debug("PAACE configuration failed for liodn %d, win_cnt =%d\n",
			 liodn, win_cnt);
		return ret;
	}

	if (win_cnt > 1) {
		subwin_size = window_size >> ilog2(win_cnt);
		for (i = 0; i < win_cnt; i++) {
			spin_lock_irqsave(&iommu_lock, flags);
			ret = pamu_disable_spaace(liodn, i);
			if (!ret)
				ret = pamu_config_spaace(liodn, win_cnt, i,
							 subwin_size, omi_index,
							 0, dma_domain->snoop_id,
							 dma_domain->stash_id,
							 0, 0);
			spin_unlock_irqrestore(&iommu_lock, flags);
			if (ret) {
				pr_debug("SPAACE configuration failed for liodn %d\n",
					 liodn);
				return ret;
			}
		}
	}

	return ret;
}

static int check_size(u64 size, dma_addr_t iova)
{
	/*
	 * Size must be a power of two and at least be equal
	 * to PAMU page size.
	 */
	if ((size & (size - 1)) || size < PAMU_PAGE_SIZE) {
		pr_debug("Size too small or not a power of two\n");
		return -EINVAL;
	}

	/* iova must be page size aligned */
	if (iova & (size - 1)) {
		pr_debug("Address is not aligned with window size\n");
		return -EINVAL;
	}

	return 0;
}

static struct fsl_dma_domain *iommu_alloc_dma_domain(void)
{
	struct fsl_dma_domain *domain;

	domain = kmem_cache_zalloc(fsl_pamu_domain_cache, GFP_KERNEL);
	if (!domain)
		return NULL;

	domain->stash_id = ~(u32)0;
	domain->snoop_id = ~(u32)0;
	domain->win_cnt = pamu_get_max_subwin_cnt();
	domain->geom_size = 0;

	INIT_LIST_HEAD(&domain->devices);

	spin_lock_init(&domain->domain_lock);

	return domain;
}

static void remove_device_ref(struct device_domain_info *info, u32 win_cnt)
{
	unsigned long flags;

	list_del(&info->link);
	spin_lock_irqsave(&iommu_lock, flags);
	if (win_cnt > 1)
		pamu_free_subwins(info->liodn);
	pamu_disable_liodn(info->liodn);
	spin_unlock_irqrestore(&iommu_lock, flags);
	spin_lock_irqsave(&device_domain_lock, flags);
	info->dev->archdata.iommu_domain = NULL;
	kmem_cache_free(iommu_devinfo_cache, info);
	spin_unlock_irqrestore(&device_domain_lock, flags);
}

static void detach_device(struct device *dev, struct fsl_dma_domain *dma_domain)
{
	struct device_domain_info *info, *tmp;
	unsigned long flags;

	spin_lock_irqsave(&dma_domain->domain_lock, flags);
	/* Remove the device from the domain device list */
	list_for_each_entry_safe(info, tmp, &dma_domain->devices, link) {
		if (!dev || (info->dev == dev))
			remove_device_ref(info, dma_domain->win_cnt);
	}
	spin_unlock_irqrestore(&dma_domain->domain_lock, flags);
}

static void attach_device(struct fsl_dma_domain *dma_domain, int liodn, struct device *dev)
{
	struct device_domain_info *info, *old_domain_info;
	unsigned long flags;

	spin_lock_irqsave(&device_domain_lock, flags);
	/*
	 * Check here if the device is already attached to domain or not.
	 * If the device is already attached to a domain detach it.
	 */
	old_domain_info = dev->archdata.iommu_domain;
	if (old_domain_info && old_domain_info->domain != dma_domain) {
		spin_unlock_irqrestore(&device_domain_lock, flags);
		detach_device(dev, old_domain_info->domain);
		spin_lock_irqsave(&device_domain_lock, flags);
	}

	info = kmem_cache_zalloc(iommu_devinfo_cache, GFP_ATOMIC);

	info->dev = dev;
	info->liodn = liodn;
	info->domain = dma_domain;

	list_add(&info->link, &dma_domain->devices);
	/*
	 * In case of devices with multiple LIODNs just store
	 * the info for the first LIODN as all
	 * LIODNs share the same domain
	 */
	if (!dev->archdata.iommu_domain)
		dev->archdata.iommu_domain = info;
	spin_unlock_irqrestore(&device_domain_lock, flags);
}

static phys_addr_t fsl_pamu_iova_to_phys(struct iommu_domain *domain,
					 dma_addr_t iova)
{
	struct fsl_dma_domain *dma_domain = to_fsl_dma_domain(domain);

	if (iova < domain->geometry.aperture_start ||
	    iova > domain->geometry.aperture_end)
		return 0;

	return get_phys_addr(dma_domain, iova);
}

static bool fsl_pamu_capable(enum iommu_cap cap)
{
	return cap == IOMMU_CAP_CACHE_COHERENCY;
}

static void fsl_pamu_domain_free(struct iommu_domain *domain)
{
	struct fsl_dma_domain *dma_domain = to_fsl_dma_domain(domain);

	/* remove all the devices from the device list */
	detach_device(NULL, dma_domain);

	dma_domain->enabled = 0;
	dma_domain->mapped = 0;

	kmem_cache_free(fsl_pamu_domain_cache, dma_domain);
}

static struct iommu_domain *fsl_pamu_domain_alloc(unsigned type)
{
	struct fsl_dma_domain *dma_domain;

	if (type != IOMMU_DOMAIN_UNMANAGED)
		return NULL;

	dma_domain = iommu_alloc_dma_domain();
	if (!dma_domain) {
		pr_debug("dma_domain allocation failed\n");
		return NULL;
	}
	/* defaul geometry 64 GB i.e. maximum system address */
	dma_domain->iommu_domain. geometry.aperture_start = 0;
	dma_domain->iommu_domain.geometry.aperture_end = (1ULL << 36) - 1;
	dma_domain->iommu_domain.geometry.force_aperture = true;

	return &dma_domain->iommu_domain;
}

/* Configure geometry settings for all LIODNs associated with domain */
static int pamu_set_domain_geometry(struct fsl_dma_domain *dma_domain,
				    struct iommu_domain_geometry *geom_attr,
				    u32 win_cnt)
{
	struct device_domain_info *info;
	int ret = 0;

	list_for_each_entry(info, &dma_domain->devices, link) {
		ret = pamu_set_liodn(info->liodn, info->dev, dma_domain,
				     geom_attr, win_cnt);
		if (ret)
			break;
	}

	return ret;
}

/* Update stash destination for all LIODNs associated with the domain */
static int update_domain_stash(struct fsl_dma_domain *dma_domain, u32 val)
{
	struct device_domain_info *info;
	int ret = 0;

	list_for_each_entry(info, &dma_domain->devices, link) {
		ret = update_liodn_stash(info->liodn, dma_domain, val);
		if (ret)
			break;
	}

	return ret;
}

/* Update domain mappings for all LIODNs associated with the domain */
static int update_domain_mapping(struct fsl_dma_domain *dma_domain, u32 wnd_nr)
{
	struct device_domain_info *info;
	int ret = 0;

	list_for_each_entry(info, &dma_domain->devices, link) {
		ret = update_liodn(info->liodn, dma_domain, wnd_nr);
		if (ret)
			break;
	}
	return ret;
}

static int disable_domain_win(struct fsl_dma_domain *dma_domain, u32 wnd_nr)
{
	struct device_domain_info *info;
	int ret = 0;

	list_for_each_entry(info, &dma_domain->devices, link) {
		if (dma_domain->win_cnt == 1 && dma_domain->enabled) {
			ret = pamu_disable_liodn(info->liodn);
			if (!ret)
				dma_domain->enabled = 0;
		} else {
			ret = pamu_disable_spaace(info->liodn, wnd_nr);
		}
	}

	return ret;
}

static void fsl_pamu_window_disable(struct iommu_domain *domain, u32 wnd_nr)
{
	struct fsl_dma_domain *dma_domain = to_fsl_dma_domain(domain);