summaryrefslogtreecommitdiff
path: root/arch/arm64/mm/dma-mapping.c
blob: 4164c5ace9f8f515c6e9ea16402b1cc18e16a432 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
/*
 * SWIOTLB-based DMA API implementation
 *
 * Copyright (C) 2012 ARM Ltd.
 * Author: Catalin Marinas <catalin.marinas@arm.com>
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include <linux/gfp.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/dma-contiguous.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/vmalloc.h>
#include <linux/swiotlb.h>
#include <linux/amba/bus.h>

#include <asm/cacheflush.h>

struct dma_map_ops *dma_ops;
EXPORT_SYMBOL(dma_ops);

static pgprot_t __get_dma_pgprot(struct dma_attrs *attrs, pgprot_t prot,
				 bool coherent)
{
	if (!coherent || dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs))
		return pgprot_writecombine(prot);
	return prot;
}

static void *__dma_alloc_coherent(struct device *dev, size_t size,
				  dma_addr_t *dma_handle, gfp_t flags,
				  struct dma_attrs *attrs)
{
	if (dev == NULL) {
		WARN_ONCE(1, "Use an actual device structure for DMA allocation\n");
		return NULL;
	}

	if (IS_ENABLED(CONFIG_ZONE_DMA) &&
	    dev->coherent_dma_mask <= DMA_BIT_MASK(32))
		flags |= GFP_DMA;
	if (IS_ENABLED(CONFIG_DMA_CMA)) {
		struct page *page;

		size = PAGE_ALIGN(size);
		page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT,
							get_order(size));
		if (!page)
			return NULL;

		*dma_handle = phys_to_dma(dev, page_to_phys(page));
		return page_address(page);
	} else {
		return swiotlb_alloc_coherent(dev, size, dma_handle, flags);
	}
}

static void __dma_free_coherent(struct device *dev, size_t size,
				void *vaddr, dma_addr_t dma_handle,
				struct dma_attrs *attrs)
{
	if (dev == NULL) {
		WARN_ONCE(1, "Use an actual device structure for DMA allocation\n");
		return;
	}

	if (IS_ENABLED(CONFIG_DMA_CMA)) {
		phys_addr_t paddr = dma_to_phys(dev, dma_handle);

		dma_release_from_contiguous(dev,
					phys_to_page(paddr),
					size >> PAGE_SHIFT);
	} else {
		swiotlb_free_coherent(dev, size, vaddr, dma_handle);
	}
}

static void *__dma_alloc_noncoherent(struct device *dev, size_t size,
				     dma_addr_t *dma_handle, gfp_t flags,
				     struct dma_attrs *attrs)
{
	struct page *page, **map;
	void *ptr, *coherent_ptr;
	int order, i;

	size = PAGE_ALIGN(size);
	order = get_order(size);

	ptr = __dma_alloc_coherent(dev, size, dma_handle, flags, attrs);
	if (!ptr)
		goto no_mem;
	map = kmalloc(sizeof(struct page *) << order, flags & ~GFP_DMA);
	if (!map)
		goto no_map;

	/* remove any dirty cache lines on the kernel alias */
	__dma_flush_range(ptr, ptr + size);

	/* create a coherent mapping */
	page = virt_to_page(ptr);
	for (i = 0; i < (size >> PAGE_SHIFT); i++)
		map[i] = page + i;
	coherent_ptr = vmap(map, size >> PAGE_SHIFT, VM_MAP,
			    __get_dma_pgprot(attrs, __pgprot(PROT_NORMAL_NC), false));
	kfree(map);
	if (!coherent_ptr)
		goto no_map;

	return coherent_ptr;

no_map:
	__dma_free_coherent(dev, size, ptr, *dma_handle, attrs);
no_mem:
	*dma_handle = ~0;
	return NULL;
}

static void __dma_free_noncoherent(struct device *dev, size_t size,
				   void *vaddr, dma_addr_t dma_handle,
				   struct dma_attrs *attrs)
{
	void *swiotlb_addr = phys_to_virt(dma_to_phys(dev, dma_handle));

	vunmap(vaddr);
	__dma_free_coherent(dev, size, swiotlb_addr, dma_handle, attrs);
}

static dma_addr_t __swiotlb_map_page(struct device *dev, struct page *page,
				     unsigned long offset, size_t size,
				     enum dma_data_direction dir,
				     struct dma_attrs *attrs)
{
	dma_addr_t dev_addr;

	dev_addr = swiotlb_map_page(dev, page, offset, size, dir, attrs);
	__dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);

	return dev_addr;
}


static void __swiotlb_unmap_page(struct device *dev, dma_addr_t dev_addr,
				 size_t size, enum dma_data_direction dir,
				 struct dma_attrs *attrs)
{
	__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
	swiotlb_unmap_page(dev, dev_addr, size, dir, attrs);
}

static int __swiotlb_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
				  int nelems, enum dma_data_direction dir,
				  struct dma_attrs *attrs)
{
	struct scatterlist *sg;
	int i, ret;

	ret = swiotlb_map_sg_attrs(dev, sgl, nelems, dir, attrs);
	for_each_sg(sgl, sg, ret, i)
		__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
			       sg->length, dir);

	return ret;
}

static void __swiotlb_unmap_sg_attrs(struct device *dev,
				     struct scatterlist *sgl, int nelems,
				     enum dma_data_direction dir,
				     struct dma_attrs *attrs)
{
	struct scatterlist *sg;
	int i;

	for_each_sg(sgl, sg, nelems, i)
		__dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
				 sg->length, dir);
	swiotlb_unmap_sg_attrs(dev, sgl, nelems, dir, attrs);
}

static void __swiotlb_sync_single_for_cpu(struct device *dev,
					  dma_addr_t dev_addr, size_t size,
					  enum dma_data_direction dir)
{
	__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
	swiotlb_sync_single_for_cpu(dev, dev_addr, size, dir);
}

static void __swiotlb_sync_single_for_device(struct device *dev,
					     dma_addr_t dev_addr, size_t size,
					     enum dma_data_direction dir)
{
	swiotlb_sync_single_for_device(dev, dev_addr, size, dir);
	__dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
}

static void __swiotlb_sync_sg_for_cpu(struct device *dev,
				      struct scatterlist *sgl, int nelems,
				      enum dma_data_direction dir)
{
	struct scatterlist *sg;
	int i;

	for_each_sg(sgl, sg, nelems, i)
		__dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
				 sg->length, dir);
	swiotlb_sync_sg_for_cpu(dev, sgl, nelems, dir);
}

static void __swiotlb_sync_sg_for_device(struct device *dev,
					 struct scatterlist *sgl, int nelems,
					 enum dma_data_direction dir)
{
	struct scatterlist *sg;
	int i;

	swiotlb_sync_sg_for_device(dev, sgl, nelems, dir);
	for_each_sg(sgl, sg, nelems, i)
		__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
			       sg->length, dir);
}

/* vma->vm_page_prot must be set appropriately before calling this function */
static int __dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
			     void *cpu_addr, dma_addr_t dma_addr, size_t size)
{
	int ret = -ENXIO;
	unsigned long nr_vma_pages = (vma->vm_end - vma->vm_start) >>
					PAGE_SHIFT;
	unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
	unsigned long pfn = dma_to_phys(dev, dma_addr) >> PAGE_SHIFT;
	unsigned long off = vma->vm_pgoff;

	if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret))
		return ret;

	if (off < nr_pages && nr_vma_pages <= (nr_pages - off)) {
		ret = remap_pfn_range(vma, vma->vm_start,
				      pfn + off,
				      vma->vm_end - vma->vm_start,
				      vma->vm_page_prot);
	}

	return ret;
}

static int __swiotlb_mmap_noncoherent(struct device *dev,
		struct vm_area_struct *vma,
		void *cpu_addr, dma_addr_t dma_addr, size_t size,
		struct dma_attrs *attrs)
{
	vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot, false);
	return __dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
}

static int __swiotlb_mmap_coherent(struct device *dev,
		struct vm_area_struct *vma,
		void *cpu_addr, dma_addr_t dma_addr, size_t size,
		struct dma_attrs *attrs)
{
	/* Just use whatever page_prot attributes were specified */
	return __dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
}

struct dma_map_ops noncoherent_swiotlb_dma_ops = {
	.alloc = __dma_alloc_noncoherent,
	.free = __dma_free_noncoherent,
	.mmap = __swiotlb_mmap_noncoherent,
	.map_page = __swiotlb_map_page,
	.unmap_page = __swiotlb_unmap_page,
	.map_sg = __swiotlb_map_sg_attrs,
	.unmap_sg = __swiotlb_unmap_sg_attrs,
	.sync_single_for_cpu = __swiotlb_sync_single_for_cpu,
	.sync_single_for_device = __swiotlb_sync_single_for_device,
	.sync_sg_for_cpu = __swiotlb_sync_sg_for_cpu,
	.sync_sg_for_device = __swiotlb_sync_sg_for_device,
	.dma_supported = swiotlb_dma_supported,
	.mapping_error = swiotlb_dma_mapping_error,
};
EXPORT_SYMBOL(noncoherent_swiotlb_dma_ops);

struct dma_map_ops coherent_swiotlb_dma_ops = {
	.alloc = __dma_alloc_coherent,
	.free = __dma_free_coherent,
	.mmap = __swiotlb_mmap_coherent,
	.map_page = swiotlb_map_page,
	.unmap_page = swiotlb_unmap_page,
	.map_sg = swiotlb_map_sg_attrs,
	.unmap_sg = swiotlb_unmap_sg_attrs,
	.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
	.sync_single_for_device = swiotlb_sync_single_for_device,
	.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
	.sync_sg_for_device = swiotlb_sync_sg_for_device,
	.dma_supported = swiotlb_dma_supported,
	.mapping_error = swiotlb_dma_mapping_error,
};
EXPORT_SYMBOL(coherent_swiotlb_dma_ops);

static int dma_bus_notifier(struct notifier_block *nb,
			    unsigned long event, void *_dev)
{
	struct device *dev = _dev;

	if (event != BUS_NOTIFY_ADD_DEVICE)
		return NOTIFY_DONE;

	if (of_property_read_bool(dev->of_node, "dma-coherent"))
		set_dma_ops(dev, &coherent_swiotlb_dma_ops);

	return NOTIFY_OK;
}

static struct notifier_block platform_bus_nb = {
	.notifier_call = dma_bus_notifier,
};

static struct notifier_block amba_bus_nb = {
	.notifier_call = dma_bus_notifier,
};

extern int swiotlb_late_init_with_default_size(size_t default_size);

static int __init swiotlb_late_init(void)
{
	size_t swiotlb_size = min(SZ_64M, MAX_ORDER_NR_PAGES << PAGE_SHIFT);

	/*
	 * These must be registered before of_platform_populate().
	 */
	bus_register_notifier(&platform_bus_type, &platform_bus_nb);
	bus_register_notifier(&amba_bustype, &amba_bus_nb);

	dma_ops = &noncoherent_swiotlb_dma_ops;

	return swiotlb_late_init_with_default_size(swiotlb_size);
}
arch_initcall(swiotlb_late_init);

#define PREALLOC_DMA_DEBUG_ENTRIES	4096

static int __init dma_debug_do_init(void)
{
	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
	return 0;
}
fs_initcall(dma_debug_do_init);