summaryrefslogtreecommitdiff
path: root/packages/linux/linux-rp-2.6.23/arm-dma-coherent.patch
blob: 2454becf667081f7ddd2193c3f34741122b66072 (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
359
360
361
Patch largely based on the work of Ian Molton (spyro@f2s.com).

Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Index: linux-2.6.23/arch/arm/mm/consistent.c
===================================================================
--- linux-2.6.23.orig/arch/arm/mm/consistent.c	2007-10-10 00:31:38.000000000 +0400
+++ linux-2.6.23/arch/arm/mm/consistent.c	2007-11-13 01:20:58.281143408 +0300
@@ -3,6 +3,8 @@
  *
  *  Copyright (C) 2000-2004 Russell King
  *
+ *  Device local coherent memory support added by Ian Molton (spyro@f2s.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.
@@ -20,6 +22,7 @@
 
 #include <asm/memory.h>
 #include <asm/cacheflush.h>
+#include <asm/io.h>
 #include <asm/tlbflush.h>
 #include <asm/sizes.h>
 
@@ -35,6 +38,13 @@
 #define CONSISTENT_PTE_INDEX(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PGDIR_SHIFT)
 #define NUM_CONSISTENT_PTES (CONSISTENT_DMA_SIZE >> PGDIR_SHIFT)
 
+struct dma_coherent_mem {
+	void		*virt_base;
+	u32		device_base;
+	int		size;
+	int		flags;
+	unsigned long	*bitmap;
+};
 
 /*
  * These are the page tables (2MB each) covering uncached, DMA consistent allocations
@@ -153,6 +163,13 @@
 	unsigned long order;
 	u64 mask = ISA_DMA_THRESHOLD, limit;
 
+	/* Following is a work-around (a.k.a. hack) to prevent pages
+	 * with __GFP_COMP being passed to split_page() which cannot
+	 * handle them.  The real problem is that this flag probably
+	 * should be 0 on ARM as it is not supported on this
+	 * platform--see CONFIG_HUGETLB_PAGE. */
+	gfp &= ~(__GFP_COMP);
+
 	if (!consistent_pte[0]) {
 		printk(KERN_ERR "%s: not initialised\n", __func__);
 		dump_stack();
@@ -160,6 +177,26 @@
 	}
 
 	if (dev) {
+
+		if (dev->dma_mem) {
+			unsigned long flags;
+			int page;
+			void *ret;
+
+			spin_lock_irqsave(&consistent_lock, flags);
+			page = bitmap_find_free_region(dev->dma_mem->bitmap,
+						       dev->dma_mem->size,
+						       get_order(size));
+			spin_unlock_irqrestore(&consistent_lock, flags);
+
+			if (page >= 0) {
+				*handle = dev->dma_mem->device_base + (page << PAGE_SHIFT);
+				ret = dev->dma_mem->virt_base + (page << PAGE_SHIFT);
+				memset(ret, 0, size);
+				return ret;
+			}
+		}
+
 		mask = dev->coherent_dma_mask;
 
 		/*
@@ -177,6 +214,9 @@
 				 mask, (unsigned long long)ISA_DMA_THRESHOLD);
 			goto no_page;
 		}
+
+		if (dev->dma_mem && dev->dma_mem->flags & DMA_MEMORY_EXCLUSIVE)
+			return NULL;
 	}
 
 	/*
@@ -360,6 +400,8 @@
 	pte_t *ptep;
 	int idx;
 	u32 off;
+	struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
+	unsigned long order;
 
 	WARN_ON(irqs_disabled());
 
@@ -369,6 +411,15 @@
 	}
 
 	size = PAGE_ALIGN(size);
+	order = get_order(size);
+
+	/* What if mem is valid and the range is not? */
+	if (mem && cpu_addr >= mem->virt_base && cpu_addr < (mem->virt_base + (mem->size << PAGE_SHIFT))) {
+		int page = (cpu_addr - mem->virt_base) >> PAGE_SHIFT;
+
+		bitmap_release_region(mem->bitmap, page, order);
+		return;
+	}
 
 	spin_lock_irqsave(&consistent_lock, flags);
 	c = vm_region_find(&consistent_head, (unsigned long)cpu_addr);
@@ -438,6 +489,81 @@
 }
 EXPORT_SYMBOL(dma_free_coherent);
 
+int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+				dma_addr_t device_addr, size_t size, int flags)
+{
+	void *mem_base;
+	int pages = size >> PAGE_SHIFT;
+	int bitmap_size = (pages + 31)/32;
+
+	if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0)
+		goto out;
+	if (!size)
+		goto out;
+	if (dev->dma_mem)
+		goto out;
+
+	/* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
+	mem_base = ioremap_nocache(bus_addr, size);
+	if (!mem_base)
+		goto out;
+
+	dev->dma_mem = kmalloc(GFP_KERNEL, sizeof(struct dma_coherent_mem));
+	if (!dev->dma_mem)
+		goto out;
+	memset(dev->dma_mem, 0, sizeof(struct dma_coherent_mem));
+	dev->dma_mem->bitmap = kmalloc(GFP_KERNEL, bitmap_size);
+	if (!dev->dma_mem->bitmap)
+		goto free1_out;
+	memset(dev->dma_mem->bitmap, 0, bitmap_size);
+
+	dev->dma_mem->virt_base = mem_base;
+	dev->dma_mem->device_base = device_addr;
+	dev->dma_mem->size = pages;
+	dev->dma_mem->flags = flags;
+
+	if (flags & DMA_MEMORY_MAP)
+		return DMA_MEMORY_MAP;
+
+	return DMA_MEMORY_IO;
+
+ free1_out:
+	kfree(dev->dma_mem->bitmap);
+ out:
+	return 0;
+}
+EXPORT_SYMBOL(dma_declare_coherent_memory);
+
+void dma_release_declared_memory(struct device *dev)
+{
+	struct dma_coherent_mem *mem = dev->dma_mem;
+
+	if (!mem)
+		return;
+	dev->dma_mem = NULL;
+	kfree(mem->bitmap);
+	kfree(mem);
+}
+EXPORT_SYMBOL(dma_release_declared_memory);
+
+void *dma_mark_declared_memory_occupied(struct device *dev,
+					dma_addr_t device_addr, size_t size)
+{
+	struct dma_coherent_mem *mem = dev->dma_mem;
+	int pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	int pos, err;
+
+	if (!mem)
+		return ERR_PTR(-EINVAL);
+
+	pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
+	err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages));
+	if (err != 0)
+		return ERR_PTR(err);
+	return mem->virt_base + (pos << PAGE_SHIFT);
+}
+EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
+
 /*
  * Initialise the consistent memory allocation.
  */
Index: linux-2.6.23/arch/arm/common/dmabounce.c
===================================================================
--- linux-2.6.23.orig/arch/arm/common/dmabounce.c	2007-10-10 00:31:38.000000000 +0400
+++ linux-2.6.23/arch/arm/common/dmabounce.c	2007-11-13 01:23:17.452501736 +0300
@@ -16,6 +16,7 @@
  *
  *  Copyright (C) 2002 Hewlett Packard Company.
  *  Copyright (C) 2004 MontaVista Software, Inc.
+ *  Copyright (C) 2007 Dmitry Baryshkov <dbaryshkov@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU General Public License
@@ -29,6 +30,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/dmapool.h>
 #include <linux/list.h>
+#include <linux/rwsem.h>
 
 #include <asm/cacheflush.h>
 
@@ -79,6 +81,75 @@
 	rwlock_t lock;
 };
 
+struct dmabounce_check_entry {
+	struct list_head	list;
+	dmabounce_check		checker;
+	void			*data;
+};
+
+static struct list_head checkers = LIST_HEAD_INIT(checkers);
+static rwlock_t checkers_lock = RW_LOCK_UNLOCKED;
+
+int
+dmabounce_register_checker(dmabounce_check function, void *data)
+{
+	unsigned long flags;
+	struct dmabounce_check_entry *entry =
+		kzalloc(sizeof(struct dmabounce_check_entry), GFP_ATOMIC);
+
+	if (!entry)
+		return ENOMEM;
+
+	INIT_LIST_HEAD(&entry->list);
+	entry->checker = function;
+	entry->data = data;
+
+	write_lock_irqsave(checkers_lock, flags);
+	list_add(&entry->list, &checkers);
+	write_unlock_irqrestore(checkers_lock, flags);
+
+	return 0;
+}
+
+void
+dmabounce_remove_checker(dmabounce_check function, void *data)
+{
+	unsigned long flags;
+	struct list_head *pos;
+
+	write_lock_irqsave(checkers_lock, flags);
+	__list_for_each(pos, &checkers) {
+		struct dmabounce_check_entry *entry = container_of(pos,
+				struct dmabounce_check_entry, list);
+		if (entry->checker == function && entry->data == data) {
+			list_del(pos);
+			write_unlock_irqrestore(checkers_lock, flags);
+			kfree(entry);
+			return;
+		}
+	}
+
+	printk(KERN_WARNING "dmabounce checker not found: %p\n", function);
+}
+
+int dma_needs_bounce(struct device *dev, dma_addr_t dma, size_t size)
+{
+	unsigned long flags;
+	struct list_head *pos;
+
+	read_lock_irqsave(checkers_lock, flags);
+	__list_for_each(pos, &checkers) {
+		struct dmabounce_check_entry *entry = container_of(pos,
+				struct dmabounce_check_entry, list);
+		if (entry->checker(dev, dma, size, entry->data)) {
+			read_unlock_irqrestore(checkers_lock, flags);
+			return 1;
+		}
+	}
+
+	read_unlock_irqrestore(checkers_lock, flags);
+	return 0;
+}
 #ifdef STATS
 static ssize_t dmabounce_show(struct device *dev, struct device_attribute *attr,
 			      char *buf)
@@ -642,7 +713,6 @@
 		dev->bus_id, dev->bus->name);
 }
 
-
 EXPORT_SYMBOL(dma_map_single);
 EXPORT_SYMBOL(dma_unmap_single);
 EXPORT_SYMBOL(dma_map_sg);
@@ -652,6 +722,9 @@
 EXPORT_SYMBOL(dma_sync_sg);
 EXPORT_SYMBOL(dmabounce_register_dev);
 EXPORT_SYMBOL(dmabounce_unregister_dev);
+EXPORT_SYMBOL(dmabounce_register_checker);
+EXPORT_SYMBOL(dmabounce_remove_checker);
+
 
 MODULE_AUTHOR("Christopher Hoover <ch@hpl.hp.com>, Deepak Saxena <dsaxena@plexity.net>");
 MODULE_DESCRIPTION("Special dma_{map/unmap/dma_sync}_* routines for systems with limited DMA windows");
Index: linux-2.6.23/include/asm-arm/dma-mapping.h
===================================================================
--- linux-2.6.23.orig/include/asm-arm/dma-mapping.h	2007-10-10 00:31:38.000000000 +0400
+++ linux-2.6.23/include/asm-arm/dma-mapping.h	2007-11-13 01:24:05.588500474 +0300
@@ -7,6 +7,18 @@
 
 #include <asm/scatterlist.h>
 
+#define ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
+extern int
+dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+			    dma_addr_t device_addr, size_t size, int flags);
+
+extern void
+dma_release_declared_memory(struct device *dev);
+
+extern void *
+dma_mark_declared_memory_occupied(struct device *dev,
+				  dma_addr_t device_addr, size_t size);
+
 /*
  * DMA-consistent mapping functions.  These allocate/free a region of
  * uncached, unwrite-buffered mapped memory space for use with DMA
@@ -433,23 +445,10 @@
  */
 extern void dmabounce_unregister_dev(struct device *);
 
-/**
- * dma_needs_bounce
- *
- * @dev: valid struct device pointer
- * @dma_handle: dma_handle of unbounced buffer
- * @size: size of region being mapped
- *
- * Platforms that utilize the dmabounce mechanism must implement
- * this function.
- *
- * The dmabounce routines call this function whenever a dma-mapping
- * is requested to determine whether a given buffer needs to be bounced
- * or not. The function must return 0 if the buffer is OK for
- * DMA access and 1 if the buffer needs to be bounced.
- *
- */
-extern int dma_needs_bounce(struct device*, dma_addr_t, size_t);
+typedef int (*dmabounce_check)(struct device *dev, dma_addr_t dma, size_t size, void *data);
+extern int dmabounce_register_checker(dmabounce_check, void *data);
+extern void dmabounce_remove_checker(dmabounce_check, void *data);
+
 #endif /* CONFIG_DMABOUNCE */
 
 #endif /* __KERNEL__ */