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v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * IOMMU API for Graphics Address Relocation Table on Tegra20
  4 *
  5 * Copyright (c) 2010-2012, NVIDIA CORPORATION.  All rights reserved.
  6 *
  7 * Author: Hiroshi DOYU <hdoyu@nvidia.com>
 
 
 
 
 
 
 
 
 
 
 
  8 */
  9
 10#define dev_fmt(fmt)	"gart: " fmt
 11
 12#include <linux/io.h>
 13#include <linux/iommu.h>
 14#include <linux/moduleparam.h>
 15#include <linux/platform_device.h>
 16#include <linux/slab.h>
 17#include <linux/spinlock.h>
 
 18#include <linux/vmalloc.h>
 
 
 
 
 
 
 19
 20#include <soc/tegra/mc.h>
 
 
 
 21
 22#define GART_REG_BASE		0x24
 23#define GART_CONFIG		(0x24 - GART_REG_BASE)
 24#define GART_ENTRY_ADDR		(0x28 - GART_REG_BASE)
 25#define GART_ENTRY_DATA		(0x2c - GART_REG_BASE)
 26
 27#define GART_ENTRY_PHYS_ADDR_VALID	BIT(31)
 28
 29#define GART_PAGE_SHIFT		12
 30#define GART_PAGE_SIZE		(1 << GART_PAGE_SHIFT)
 31#define GART_PAGE_MASK		GENMASK(30, GART_PAGE_SHIFT)
 
 32
 33/* bitmap of the page sizes currently supported */
 34#define GART_IOMMU_PGSIZES	(GART_PAGE_SIZE)
 
 
 35
 36struct gart_device {
 37	void __iomem		*regs;
 38	u32			*savedata;
 39	unsigned long		iovmm_base;	/* offset to vmm_area start */
 40	unsigned long		iovmm_end;	/* offset to vmm_area end */
 41	spinlock_t		pte_lock;	/* for pagetable */
 42	spinlock_t		dom_lock;	/* for active domain */
 43	unsigned int		active_devices;	/* number of active devices */
 44	struct iommu_domain	*active_domain;	/* current active domain */
 45	struct iommu_device	iommu;		/* IOMMU Core handle */
 46	struct device		*dev;
 
 
 
 
 
 
 
 47};
 48
 49static struct gart_device *gart_handle; /* unique for a system */
 50
 51static bool gart_debug;
 
 
 
 
 
 
 52
 53/*
 54 * Any interaction between any block on PPSB and a block on APB or AHB
 55 * must have these read-back to ensure the APB/AHB bus transaction is
 56 * complete before initiating activity on the PPSB block.
 57 */
 58#define FLUSH_GART_REGS(gart)	readl_relaxed((gart)->regs + GART_CONFIG)
 59
 60#define for_each_gart_pte(gart, iova)					\
 61	for (iova = gart->iovmm_base;					\
 62	     iova < gart->iovmm_end;					\
 63	     iova += GART_PAGE_SIZE)
 64
 65static inline void gart_set_pte(struct gart_device *gart,
 66				unsigned long iova, unsigned long pte)
 67{
 68	writel_relaxed(iova, gart->regs + GART_ENTRY_ADDR);
 69	writel_relaxed(pte, gart->regs + GART_ENTRY_DATA);
 
 
 
 70}
 71
 72static inline unsigned long gart_read_pte(struct gart_device *gart,
 73					  unsigned long iova)
 74{
 75	unsigned long pte;
 76
 77	writel_relaxed(iova, gart->regs + GART_ENTRY_ADDR);
 78	pte = readl_relaxed(gart->regs + GART_ENTRY_DATA);
 79
 80	return pte;
 81}
 82
 83static void do_gart_setup(struct gart_device *gart, const u32 *data)
 84{
 85	unsigned long iova;
 86
 87	for_each_gart_pte(gart, iova)
 88		gart_set_pte(gart, iova, data ? *(data++) : 0);
 89
 90	writel_relaxed(1, gart->regs + GART_CONFIG);
 91	FLUSH_GART_REGS(gart);
 92}
 93
 94static inline bool gart_iova_range_invalid(struct gart_device *gart,
 95					   unsigned long iova, size_t bytes)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 96{
 97	return unlikely(iova < gart->iovmm_base || bytes != GART_PAGE_SIZE ||
 98			iova + bytes > gart->iovmm_end);
 99}
 
100
101static inline bool gart_pte_valid(struct gart_device *gart, unsigned long iova)
 
102{
103	return !!(gart_read_pte(gart, iova) & GART_ENTRY_PHYS_ADDR_VALID);
 
 
 
 
 
 
 
 
 
 
 
104}
105
106static int gart_iommu_attach_dev(struct iommu_domain *domain,
107				 struct device *dev)
108{
109	struct gart_device *gart = gart_handle;
110	int ret = 0;
111
112	spin_lock(&gart->dom_lock);
113
114	if (gart->active_domain && gart->active_domain != domain) {
115		ret = -EINVAL;
116	} else if (dev_iommu_priv_get(dev) != domain) {
117		dev_iommu_priv_set(dev, domain);
118		gart->active_domain = domain;
119		gart->active_devices++;
 
 
 
 
 
 
 
120	}
 
 
 
 
121
122	spin_unlock(&gart->dom_lock);
123
124	return ret;
 
125}
126
127static void gart_iommu_detach_dev(struct iommu_domain *domain,
128				  struct device *dev)
129{
130	struct gart_device *gart = gart_handle;
131
132	spin_lock(&gart->dom_lock);
133
134	if (dev_iommu_priv_get(dev) == domain) {
135		dev_iommu_priv_set(dev, NULL);
136
137		if (--gart->active_devices == 0)
138			gart->active_domain = NULL;
 
 
 
 
139	}
140
141	spin_unlock(&gart->dom_lock);
 
142}
143
144static struct iommu_domain *gart_iommu_domain_alloc(unsigned type)
145{
146	struct iommu_domain *domain;
 
147
148	if (type != IOMMU_DOMAIN_UNMANAGED)
149		return NULL;
150
151	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
152	if (domain) {
153		domain->geometry.aperture_start = gart_handle->iovmm_base;
154		domain->geometry.aperture_end = gart_handle->iovmm_end - 1;
155		domain->geometry.force_aperture = true;
156	}
157
158	return domain;
 
 
 
 
 
 
 
 
 
 
159}
160
161static void gart_iommu_domain_free(struct iommu_domain *domain)
162{
163	WARN_ON(gart_handle->active_domain == domain);
164	kfree(domain);
165}
166
167static inline int __gart_iommu_map(struct gart_device *gart, unsigned long iova,
168				   unsigned long pa)
169{
170	if (unlikely(gart_debug && gart_pte_valid(gart, iova))) {
171		dev_err(gart->dev, "Page entry is in-use\n");
172		return -EINVAL;
 
 
 
173	}
174
175	gart_set_pte(gart, iova, GART_ENTRY_PHYS_ADDR_VALID | pa);
176
177	return 0;
178}
179
180static int gart_iommu_map(struct iommu_domain *domain, unsigned long iova,
181			  phys_addr_t pa, size_t bytes, int prot, gfp_t gfp)
182{
183	struct gart_device *gart = gart_handle;
184	int ret;
 
 
185
186	if (gart_iova_range_invalid(gart, iova, bytes))
187		return -EINVAL;
188
189	spin_lock(&gart->pte_lock);
190	ret = __gart_iommu_map(gart, iova, (unsigned long)pa);
191	spin_unlock(&gart->pte_lock);
192
193	return ret;
194}
195
196static inline int __gart_iommu_unmap(struct gart_device *gart,
197				     unsigned long iova)
198{
199	if (unlikely(gart_debug && !gart_pte_valid(gart, iova))) {
200		dev_err(gart->dev, "Page entry is invalid\n");
201		return -EINVAL;
202	}
203
204	gart_set_pte(gart, iova, 0);
205
206	return 0;
207}
208
209static size_t gart_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
210			       size_t bytes, struct iommu_iotlb_gather *gather)
211{
212	struct gart_device *gart = gart_handle;
213	int err;
 
214
215	if (gart_iova_range_invalid(gart, iova, bytes))
216		return 0;
217
218	spin_lock(&gart->pte_lock);
219	err = __gart_iommu_unmap(gart, iova);
220	spin_unlock(&gart->pte_lock);
221
222	return err ? 0 : bytes;
223}
224
225static phys_addr_t gart_iommu_iova_to_phys(struct iommu_domain *domain,
226					   dma_addr_t iova)
227{
228	struct gart_device *gart = gart_handle;
 
229	unsigned long pte;
 
 
230
231	if (gart_iova_range_invalid(gart, iova, GART_PAGE_SIZE))
232		return -EINVAL;
233
234	spin_lock(&gart->pte_lock);
235	pte = gart_read_pte(gart, iova);
236	spin_unlock(&gart->pte_lock);
237
238	return pte & GART_PAGE_MASK;
 
 
 
 
 
 
 
239}
240
241static struct iommu_device *gart_iommu_probe_device(struct device *dev)
242{
243	if (!dev_iommu_fwspec_get(dev))
244		return ERR_PTR(-ENODEV);
245
246	return &gart_handle->iommu;
247}
248
249static int gart_iommu_of_xlate(struct device *dev,
250			       struct of_phandle_args *args)
251{
252	return 0;
253}
254
255static void gart_iommu_sync_map(struct iommu_domain *domain, unsigned long iova,
256				size_t size)
257{
258	FLUSH_GART_REGS(gart_handle);
 
 
 
 
259}
260
261static void gart_iommu_sync(struct iommu_domain *domain,
262			    struct iommu_iotlb_gather *gather)
263{
264	size_t length = gather->end - gather->start + 1;
265
266	gart_iommu_sync_map(domain, gather->start, length);
267}
268
269static const struct iommu_ops gart_iommu_ops = {
 
270	.domain_alloc	= gart_iommu_domain_alloc,
271	.probe_device	= gart_iommu_probe_device,
 
 
 
 
272	.device_group	= generic_device_group,
 
 
 
 
273	.pgsize_bitmap	= GART_IOMMU_PGSIZES,
274	.of_xlate	= gart_iommu_of_xlate,
275	.default_domain_ops = &(const struct iommu_domain_ops) {
276		.attach_dev	= gart_iommu_attach_dev,
277		.detach_dev	= gart_iommu_detach_dev,
278		.map		= gart_iommu_map,
279		.unmap		= gart_iommu_unmap,
280		.iova_to_phys	= gart_iommu_iova_to_phys,
281		.iotlb_sync_map	= gart_iommu_sync_map,
282		.iotlb_sync	= gart_iommu_sync,
283		.free		= gart_iommu_domain_free,
284	}
285};
286
287int tegra_gart_suspend(struct gart_device *gart)
288{
289	u32 *data = gart->savedata;
290	unsigned long iova;
 
 
291
292	/*
293	 * All GART users shall be suspended at this point. Disable
294	 * address translation to trap all GART accesses as invalid
295	 * memory accesses.
296	 */
297	writel_relaxed(0, gart->regs + GART_CONFIG);
298	FLUSH_GART_REGS(gart);
299
300	for_each_gart_pte(gart, iova)
301		*(data++) = gart_read_pte(gart, iova);
302
303	return 0;
304}
305
306int tegra_gart_resume(struct gart_device *gart)
307{
308	do_gart_setup(gart, gart->savedata);
 
309
 
 
 
310	return 0;
311}
312
313struct gart_device *tegra_gart_probe(struct device *dev, struct tegra_mc *mc)
314{
315	struct gart_device *gart;
316	struct resource *res;
317	int err;
 
 
 
 
 
318
319	BUILD_BUG_ON(PAGE_SHIFT != GART_PAGE_SHIFT);
320
321	/* the GART memory aperture is required */
322	res = platform_get_resource(to_platform_device(dev), IORESOURCE_MEM, 1);
323	if (!res) {
324		dev_err(dev, "Memory aperture resource unavailable\n");
325		return ERR_PTR(-ENXIO);
 
326	}
327
328	gart = kzalloc(sizeof(*gart), GFP_KERNEL);
329	if (!gart)
330		return ERR_PTR(-ENOMEM);
 
 
331
332	gart_handle = gart;
 
 
 
 
333
334	gart->dev = dev;
335	gart->regs = mc->regs + GART_REG_BASE;
336	gart->iovmm_base = res->start;
337	gart->iovmm_end = res->end + 1;
338	spin_lock_init(&gart->pte_lock);
339	spin_lock_init(&gart->dom_lock);
340
341	do_gart_setup(gart, NULL);
342
343	err = iommu_device_sysfs_add(&gart->iommu, dev, NULL, "gart");
344	if (err)
345		goto free_gart;
346
347	err = iommu_device_register(&gart->iommu, &gart_iommu_ops, dev);
348	if (err)
349		goto remove_sysfs;
 
 
 
 
 
 
 
350
351	gart->savedata = vmalloc(resource_size(res) / GART_PAGE_SIZE *
352				 sizeof(u32));
353	if (!gart->savedata) {
354		err = -ENOMEM;
355		goto unregister_iommu;
356	}
357
358	return gart;
 
 
 
 
 
 
 
 
 
 
359
360unregister_iommu:
361	iommu_device_unregister(&gart->iommu);
362remove_sysfs:
363	iommu_device_sysfs_remove(&gart->iommu);
364free_gart:
365	kfree(gart);
366
367	return ERR_PTR(err);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
368}
369
370module_param(gart_debug, bool, 0644);
371MODULE_PARM_DESC(gart_debug, "Enable GART debugging");
 
 
 
 
 
 
 
 
 
 
v4.17
 
  1/*
  2 * IOMMU API for GART in Tegra20
  3 *
  4 * Copyright (c) 2010-2012, NVIDIA CORPORATION.  All rights reserved.
  5 *
  6 * This program is free software; you can redistribute it and/or modify it
  7 * under the terms and conditions of the GNU General Public License,
  8 * version 2, as published by the Free Software Foundation.
  9 *
 10 * This program is distributed in the hope it will be useful, but WITHOUT
 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 13 * more details.
 14 *
 15 * You should have received a copy of the GNU General Public License along with
 16 * this program; if not, write to the Free Software Foundation, Inc.,
 17 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 18 */
 19
 20#define pr_fmt(fmt)	"%s(): " fmt, __func__
 21
 22#include <linux/module.h>
 
 
 23#include <linux/platform_device.h>
 
 24#include <linux/spinlock.h>
 25#include <linux/slab.h>
 26#include <linux/vmalloc.h>
 27#include <linux/mm.h>
 28#include <linux/list.h>
 29#include <linux/device.h>
 30#include <linux/io.h>
 31#include <linux/iommu.h>
 32#include <linux/of.h>
 33
 34#include <asm/cacheflush.h>
 35
 36/* bitmap of the page sizes currently supported */
 37#define GART_IOMMU_PGSIZES	(SZ_4K)
 38
 39#define GART_REG_BASE		0x24
 40#define GART_CONFIG		(0x24 - GART_REG_BASE)
 41#define GART_ENTRY_ADDR		(0x28 - GART_REG_BASE)
 42#define GART_ENTRY_DATA		(0x2c - GART_REG_BASE)
 43#define GART_ENTRY_PHYS_ADDR_VALID	(1 << 31)
 
 44
 45#define GART_PAGE_SHIFT		12
 46#define GART_PAGE_SIZE		(1 << GART_PAGE_SHIFT)
 47#define GART_PAGE_MASK						\
 48	(~(GART_PAGE_SIZE - 1) & ~GART_ENTRY_PHYS_ADDR_VALID)
 49
 50struct gart_client {
 51	struct device		*dev;
 52	struct list_head	list;
 53};
 54
 55struct gart_device {
 56	void __iomem		*regs;
 57	u32			*savedata;
 58	u32			page_count;	/* total remappable size */
 59	dma_addr_t		iovmm_base;	/* offset to vmm_area */
 60	spinlock_t		pte_lock;	/* for pagetable */
 61	struct list_head	client;
 62	spinlock_t		client_lock;	/* for client list */
 
 
 63	struct device		*dev;
 64
 65	struct iommu_device	iommu;		/* IOMMU Core handle */
 66};
 67
 68struct gart_domain {
 69	struct iommu_domain domain;		/* generic domain handle */
 70	struct gart_device *gart;		/* link to gart device   */
 71};
 72
 73static struct gart_device *gart_handle; /* unique for a system */
 74
 75#define GART_PTE(_pfn)						\
 76	(GART_ENTRY_PHYS_ADDR_VALID | ((_pfn) << PAGE_SHIFT))
 77
 78static struct gart_domain *to_gart_domain(struct iommu_domain *dom)
 79{
 80	return container_of(dom, struct gart_domain, domain);
 81}
 82
 83/*
 84 * Any interaction between any block on PPSB and a block on APB or AHB
 85 * must have these read-back to ensure the APB/AHB bus transaction is
 86 * complete before initiating activity on the PPSB block.
 87 */
 88#define FLUSH_GART_REGS(gart)	((void)readl((gart)->regs + GART_CONFIG))
 89
 90#define for_each_gart_pte(gart, iova)					\
 91	for (iova = gart->iovmm_base;					\
 92	     iova < gart->iovmm_base + GART_PAGE_SIZE * gart->page_count; \
 93	     iova += GART_PAGE_SIZE)
 94
 95static inline void gart_set_pte(struct gart_device *gart,
 96				unsigned long offs, u32 pte)
 97{
 98	writel(offs, gart->regs + GART_ENTRY_ADDR);
 99	writel(pte, gart->regs + GART_ENTRY_DATA);
100
101	dev_dbg(gart->dev, "%s %08lx:%08x\n",
102		 pte ? "map" : "unmap", offs, pte & GART_PAGE_MASK);
103}
104
105static inline unsigned long gart_read_pte(struct gart_device *gart,
106					  unsigned long offs)
107{
108	unsigned long pte;
109
110	writel(offs, gart->regs + GART_ENTRY_ADDR);
111	pte = readl(gart->regs + GART_ENTRY_DATA);
112
113	return pte;
114}
115
116static void do_gart_setup(struct gart_device *gart, const u32 *data)
117{
118	unsigned long iova;
119
120	for_each_gart_pte(gart, iova)
121		gart_set_pte(gart, iova, data ? *(data++) : 0);
122
123	writel(1, gart->regs + GART_CONFIG);
124	FLUSH_GART_REGS(gart);
125}
126
127#ifdef DEBUG
128static void gart_dump_table(struct gart_device *gart)
129{
130	unsigned long iova;
131	unsigned long flags;
132
133	spin_lock_irqsave(&gart->pte_lock, flags);
134	for_each_gart_pte(gart, iova) {
135		unsigned long pte;
136
137		pte = gart_read_pte(gart, iova);
138
139		dev_dbg(gart->dev, "%s %08lx:%08lx\n",
140			(GART_ENTRY_PHYS_ADDR_VALID & pte) ? "v" : " ",
141			iova, pte & GART_PAGE_MASK);
142	}
143	spin_unlock_irqrestore(&gart->pte_lock, flags);
144}
145#else
146static inline void gart_dump_table(struct gart_device *gart)
147{
 
 
148}
149#endif
150
151static inline bool gart_iova_range_valid(struct gart_device *gart,
152					 unsigned long iova, size_t bytes)
153{
154	unsigned long iova_start, iova_end, gart_start, gart_end;
155
156	iova_start = iova;
157	iova_end = iova_start + bytes - 1;
158	gart_start = gart->iovmm_base;
159	gart_end = gart_start + gart->page_count * GART_PAGE_SIZE - 1;
160
161	if (iova_start < gart_start)
162		return false;
163	if (iova_end > gart_end)
164		return false;
165	return true;
166}
167
168static int gart_iommu_attach_dev(struct iommu_domain *domain,
169				 struct device *dev)
170{
171	struct gart_domain *gart_domain = to_gart_domain(domain);
172	struct gart_device *gart = gart_domain->gart;
173	struct gart_client *client, *c;
174	int err = 0;
175
176	client = devm_kzalloc(gart->dev, sizeof(*c), GFP_KERNEL);
177	if (!client)
178		return -ENOMEM;
179	client->dev = dev;
180
181	spin_lock(&gart->client_lock);
182	list_for_each_entry(c, &gart->client, list) {
183		if (c->dev == dev) {
184			dev_err(gart->dev,
185				"%s is already attached\n", dev_name(dev));
186			err = -EINVAL;
187			goto fail;
188		}
189	}
190	list_add(&client->list, &gart->client);
191	spin_unlock(&gart->client_lock);
192	dev_dbg(gart->dev, "Attached %s\n", dev_name(dev));
193	return 0;
194
195fail:
196	devm_kfree(gart->dev, client);
197	spin_unlock(&gart->client_lock);
198	return err;
199}
200
201static void gart_iommu_detach_dev(struct iommu_domain *domain,
202				  struct device *dev)
203{
204	struct gart_domain *gart_domain = to_gart_domain(domain);
205	struct gart_device *gart = gart_domain->gart;
206	struct gart_client *c;
207
208	spin_lock(&gart->client_lock);
209
210	list_for_each_entry(c, &gart->client, list) {
211		if (c->dev == dev) {
212			list_del(&c->list);
213			devm_kfree(gart->dev, c);
214			dev_dbg(gart->dev, "Detached %s\n", dev_name(dev));
215			goto out;
216		}
217	}
218	dev_err(gart->dev, "Couldn't find\n");
219out:
220	spin_unlock(&gart->client_lock);
221}
222
223static struct iommu_domain *gart_iommu_domain_alloc(unsigned type)
224{
225	struct gart_domain *gart_domain;
226	struct gart_device *gart;
227
228	if (type != IOMMU_DOMAIN_UNMANAGED)
229		return NULL;
230
231	gart = gart_handle;
232	if (!gart)
233		return NULL;
 
 
 
234
235	gart_domain = kzalloc(sizeof(*gart_domain), GFP_KERNEL);
236	if (!gart_domain)
237		return NULL;
238
239	gart_domain->gart = gart;
240	gart_domain->domain.geometry.aperture_start = gart->iovmm_base;
241	gart_domain->domain.geometry.aperture_end = gart->iovmm_base +
242					gart->page_count * GART_PAGE_SIZE - 1;
243	gart_domain->domain.geometry.force_aperture = true;
244
245	return &gart_domain->domain;
246}
247
248static void gart_iommu_domain_free(struct iommu_domain *domain)
249{
250	struct gart_domain *gart_domain = to_gart_domain(domain);
251	struct gart_device *gart = gart_domain->gart;
 
252
253	if (gart) {
254		spin_lock(&gart->client_lock);
255		if (!list_empty(&gart->client)) {
256			struct gart_client *c;
257
258			list_for_each_entry(c, &gart->client, list)
259				gart_iommu_detach_dev(domain, c->dev);
260		}
261		spin_unlock(&gart->client_lock);
262	}
263
264	kfree(gart_domain);
 
 
265}
266
267static int gart_iommu_map(struct iommu_domain *domain, unsigned long iova,
268			  phys_addr_t pa, size_t bytes, int prot)
269{
270	struct gart_domain *gart_domain = to_gart_domain(domain);
271	struct gart_device *gart = gart_domain->gart;
272	unsigned long flags;
273	unsigned long pfn;
274
275	if (!gart_iova_range_valid(gart, iova, bytes))
276		return -EINVAL;
277
278	spin_lock_irqsave(&gart->pte_lock, flags);
279	pfn = __phys_to_pfn(pa);
280	if (!pfn_valid(pfn)) {
281		dev_err(gart->dev, "Invalid page: %pa\n", &pa);
282		spin_unlock_irqrestore(&gart->pte_lock, flags);
 
 
 
 
 
 
 
283		return -EINVAL;
284	}
285	gart_set_pte(gart, iova, GART_PTE(pfn));
286	FLUSH_GART_REGS(gart);
287	spin_unlock_irqrestore(&gart->pte_lock, flags);
288	return 0;
289}
290
291static size_t gart_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
292			       size_t bytes)
293{
294	struct gart_domain *gart_domain = to_gart_domain(domain);
295	struct gart_device *gart = gart_domain->gart;
296	unsigned long flags;
297
298	if (!gart_iova_range_valid(gart, iova, bytes))
299		return 0;
300
301	spin_lock_irqsave(&gart->pte_lock, flags);
302	gart_set_pte(gart, iova, 0);
303	FLUSH_GART_REGS(gart);
304	spin_unlock_irqrestore(&gart->pte_lock, flags);
305	return 0;
306}
307
308static phys_addr_t gart_iommu_iova_to_phys(struct iommu_domain *domain,
309					   dma_addr_t iova)
310{
311	struct gart_domain *gart_domain = to_gart_domain(domain);
312	struct gart_device *gart = gart_domain->gart;
313	unsigned long pte;
314	phys_addr_t pa;
315	unsigned long flags;
316
317	if (!gart_iova_range_valid(gart, iova, 0))
318		return -EINVAL;
319
320	spin_lock_irqsave(&gart->pte_lock, flags);
321	pte = gart_read_pte(gart, iova);
322	spin_unlock_irqrestore(&gart->pte_lock, flags);
323
324	pa = (pte & GART_PAGE_MASK);
325	if (!pfn_valid(__phys_to_pfn(pa))) {
326		dev_err(gart->dev, "No entry for %08llx:%pa\n",
327			 (unsigned long long)iova, &pa);
328		gart_dump_table(gart);
329		return -EINVAL;
330	}
331	return pa;
332}
333
334static bool gart_iommu_capable(enum iommu_cap cap)
335{
336	return false;
 
 
 
337}
338
339static int gart_iommu_add_device(struct device *dev)
 
340{
341	struct iommu_group *group = iommu_group_get_for_dev(dev);
 
342
343	if (IS_ERR(group))
344		return PTR_ERR(group);
345
346	iommu_group_put(group);
347
348	iommu_device_link(&gart_handle->iommu, dev);
349
350	return 0;
351}
352
353static void gart_iommu_remove_device(struct device *dev)
 
354{
355	iommu_group_remove_device(dev);
356	iommu_device_unlink(&gart_handle->iommu, dev);
 
357}
358
359static const struct iommu_ops gart_iommu_ops = {
360	.capable	= gart_iommu_capable,
361	.domain_alloc	= gart_iommu_domain_alloc,
362	.domain_free	= gart_iommu_domain_free,
363	.attach_dev	= gart_iommu_attach_dev,
364	.detach_dev	= gart_iommu_detach_dev,
365	.add_device	= gart_iommu_add_device,
366	.remove_device	= gart_iommu_remove_device,
367	.device_group	= generic_device_group,
368	.map		= gart_iommu_map,
369	.map_sg		= default_iommu_map_sg,
370	.unmap		= gart_iommu_unmap,
371	.iova_to_phys	= gart_iommu_iova_to_phys,
372	.pgsize_bitmap	= GART_IOMMU_PGSIZES,
 
 
 
 
 
 
 
 
 
 
 
373};
374
375static int tegra_gart_suspend(struct device *dev)
376{
377	struct gart_device *gart = dev_get_drvdata(dev);
378	unsigned long iova;
379	u32 *data = gart->savedata;
380	unsigned long flags;
381
382	spin_lock_irqsave(&gart->pte_lock, flags);
 
 
 
 
 
 
 
383	for_each_gart_pte(gart, iova)
384		*(data++) = gart_read_pte(gart, iova);
385	spin_unlock_irqrestore(&gart->pte_lock, flags);
386	return 0;
387}
388
389static int tegra_gart_resume(struct device *dev)
390{
391	struct gart_device *gart = dev_get_drvdata(dev);
392	unsigned long flags;
393
394	spin_lock_irqsave(&gart->pte_lock, flags);
395	do_gart_setup(gart, gart->savedata);
396	spin_unlock_irqrestore(&gart->pte_lock, flags);
397	return 0;
398}
399
400static int tegra_gart_probe(struct platform_device *pdev)
401{
402	struct gart_device *gart;
403	struct resource *res, *res_remap;
404	void __iomem *gart_regs;
405	struct device *dev = &pdev->dev;
406	int ret;
407
408	if (gart_handle)
409		return -EIO;
410
411	BUILD_BUG_ON(PAGE_SHIFT != GART_PAGE_SHIFT);
412
413	/* the GART memory aperture is required */
414	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
415	res_remap = platform_get_resource(pdev, IORESOURCE_MEM, 1);
416	if (!res || !res_remap) {
417		dev_err(dev, "GART memory aperture expected\n");
418		return -ENXIO;
419	}
420
421	gart = devm_kzalloc(dev, sizeof(*gart), GFP_KERNEL);
422	if (!gart) {
423		dev_err(dev, "failed to allocate gart_device\n");
424		return -ENOMEM;
425	}
426
427	gart_regs = devm_ioremap(dev, res->start, resource_size(res));
428	if (!gart_regs) {
429		dev_err(dev, "failed to remap GART registers\n");
430		return -ENXIO;
431	}
432
433	ret = iommu_device_sysfs_add(&gart->iommu, &pdev->dev, NULL,
434				     dev_name(&pdev->dev));
435	if (ret) {
436		dev_err(dev, "Failed to register IOMMU in sysfs\n");
437		return ret;
438	}
439
440	iommu_device_set_ops(&gart->iommu, &gart_iommu_ops);
441
442	ret = iommu_device_register(&gart->iommu);
443	if (ret) {
444		dev_err(dev, "Failed to register IOMMU\n");
445		iommu_device_sysfs_remove(&gart->iommu);
446		return ret;
447	}
448
449	gart->dev = &pdev->dev;
450	spin_lock_init(&gart->pte_lock);
451	spin_lock_init(&gart->client_lock);
452	INIT_LIST_HEAD(&gart->client);
453	gart->regs = gart_regs;
454	gart->iovmm_base = (dma_addr_t)res_remap->start;
455	gart->page_count = (resource_size(res_remap) >> GART_PAGE_SHIFT);
456
457	gart->savedata = vmalloc(sizeof(u32) * gart->page_count);
 
458	if (!gart->savedata) {
459		dev_err(dev, "failed to allocate context save area\n");
460		return -ENOMEM;
461	}
462
463	platform_set_drvdata(pdev, gart);
464	do_gart_setup(gart, NULL);
465
466	gart_handle = gart;
467
468	return 0;
469}
470
471static int tegra_gart_remove(struct platform_device *pdev)
472{
473	struct gart_device *gart = platform_get_drvdata(pdev);
474
 
475	iommu_device_unregister(&gart->iommu);
 
476	iommu_device_sysfs_remove(&gart->iommu);
 
 
477
478	writel(0, gart->regs + GART_CONFIG);
479	if (gart->savedata)
480		vfree(gart->savedata);
481	gart_handle = NULL;
482	return 0;
483}
484
485static const struct dev_pm_ops tegra_gart_pm_ops = {
486	.suspend	= tegra_gart_suspend,
487	.resume		= tegra_gart_resume,
488};
489
490static const struct of_device_id tegra_gart_of_match[] = {
491	{ .compatible = "nvidia,tegra20-gart", },
492	{ },
493};
494MODULE_DEVICE_TABLE(of, tegra_gart_of_match);
495
496static struct platform_driver tegra_gart_driver = {
497	.probe		= tegra_gart_probe,
498	.remove		= tegra_gart_remove,
499	.driver = {
500		.name	= "tegra-gart",
501		.pm	= &tegra_gart_pm_ops,
502		.of_match_table = tegra_gart_of_match,
503	},
504};
505
506static int tegra_gart_init(void)
507{
508	return platform_driver_register(&tegra_gart_driver);
509}
510
511static void __exit tegra_gart_exit(void)
512{
513	platform_driver_unregister(&tegra_gart_driver);
514}
515
516subsys_initcall(tegra_gart_init);
517module_exit(tegra_gart_exit);
518
519MODULE_DESCRIPTION("IOMMU API for GART in Tegra20");
520MODULE_AUTHOR("Hiroshi DOYU <hdoyu@nvidia.com>");
521MODULE_ALIAS("platform:tegra-gart");
522MODULE_LICENSE("GPL v2");