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
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
User DMA
Copyright (C) 2003-2004 Kevin Thayer <nufan_wfk at yahoo.com>
Copyright (C) 2004 Chris Kennedy <c@groovy.org>
Copyright (C) 2005-2007 Hans Verkuil <hverkuil@xs4all.nl>
*/
#include "ivtv-driver.h"
#include "ivtv-udma.h"
void ivtv_udma_get_page_info(struct ivtv_dma_page_info *dma_page, unsigned long first, unsigned long size)
{
dma_page->uaddr = first & PAGE_MASK;
dma_page->offset = first & ~PAGE_MASK;
dma_page->tail = 1 + ((first+size-1) & ~PAGE_MASK);
dma_page->first = (first & PAGE_MASK) >> PAGE_SHIFT;
dma_page->last = ((first+size-1) & PAGE_MASK) >> PAGE_SHIFT;
dma_page->page_count = dma_page->last - dma_page->first + 1;
if (dma_page->page_count == 1) dma_page->tail -= dma_page->offset;
}
int ivtv_udma_fill_sg_list (struct ivtv_user_dma *dma, struct ivtv_dma_page_info *dma_page, int map_offset)
{
int i, offset;
unsigned long flags;
if (map_offset < 0)
return map_offset;
offset = dma_page->offset;
/* Fill SG Array with new values */
for (i = 0; i < dma_page->page_count; i++) {
unsigned int len = (i == dma_page->page_count - 1) ?
dma_page->tail : PAGE_SIZE - offset;
if (PageHighMem(dma->map[map_offset])) {
void *src;
if (dma->bouncemap[map_offset] == NULL)
dma->bouncemap[map_offset] = alloc_page(GFP_KERNEL);
if (dma->bouncemap[map_offset] == NULL)
return -1;
local_irq_save(flags);
src = kmap_atomic(dma->map[map_offset]) + offset;
memcpy(page_address(dma->bouncemap[map_offset]) + offset, src, len);
kunmap_atomic(src);
local_irq_restore(flags);
sg_set_page(&dma->SGlist[map_offset], dma->bouncemap[map_offset], len, offset);
}
else {
sg_set_page(&dma->SGlist[map_offset], dma->map[map_offset], len, offset);
}
offset = 0;
map_offset++;
}
return map_offset;
}
void ivtv_udma_fill_sg_array (struct ivtv_user_dma *dma, u32 buffer_offset, u32 buffer_offset_2, u32 split) {
int i;
struct scatterlist *sg;
for_each_sg(dma->SGlist, sg, dma->SG_length, i) {
dma->SGarray[i].size = cpu_to_le32(sg_dma_len(sg));
dma->SGarray[i].src = cpu_to_le32(sg_dma_address(sg));
dma->SGarray[i].dst = cpu_to_le32(buffer_offset);
buffer_offset += sg_dma_len(sg);
split -= sg_dma_len(sg);
if (split == 0)
buffer_offset = buffer_offset_2;
}
}
/* User DMA Buffers */
void ivtv_udma_alloc(struct ivtv *itv)
{
if (itv->udma.SG_handle == 0) {
/* Map DMA Page Array Buffer */
itv->udma.SG_handle = dma_map_single(&itv->pdev->dev,
itv->udma.SGarray,
sizeof(itv->udma.SGarray),
DMA_TO_DEVICE);
ivtv_udma_sync_for_cpu(itv);
}
}
int ivtv_udma_setup(struct ivtv *itv, unsigned long ivtv_dest_addr,
void __user *userbuf, int size_in_bytes)
{
struct ivtv_dma_page_info user_dma;
struct ivtv_user_dma *dma = &itv->udma;
int err;
IVTV_DEBUG_DMA("ivtv_udma_setup, dst: 0x%08x\n", (unsigned int)ivtv_dest_addr);
/* Still in USE */
if (dma->SG_length || dma->page_count) {
IVTV_DEBUG_WARN("ivtv_udma_setup: SG_length %d page_count %d still full?\n",
dma->SG_length, dma->page_count);
return -EBUSY;
}
ivtv_udma_get_page_info(&user_dma, (unsigned long)userbuf, size_in_bytes);
if (user_dma.page_count <= 0) {
IVTV_DEBUG_WARN("ivtv_udma_setup: Error %d page_count from %d bytes %d offset\n",
user_dma.page_count, size_in_bytes, user_dma.offset);
return -EINVAL;
}
/* Pin user pages for DMA Xfer */
err = pin_user_pages_unlocked(user_dma.uaddr, user_dma.page_count,
dma->map, FOLL_FORCE);
if (user_dma.page_count != err) {
IVTV_DEBUG_WARN("failed to map user pages, returned %d instead of %d\n",
err, user_dma.page_count);
if (err >= 0) {
unpin_user_pages(dma->map, err);
return -EINVAL;
}
return err;
}
dma->page_count = user_dma.page_count;
/* Fill SG List with new values */
if (ivtv_udma_fill_sg_list(dma, &user_dma, 0) < 0) {
unpin_user_pages(dma->map, dma->page_count);
dma->page_count = 0;
return -ENOMEM;
}
/* Map SG List */
dma->SG_length = dma_map_sg(&itv->pdev->dev, dma->SGlist,
dma->page_count, DMA_TO_DEVICE);
/* Fill SG Array with new values */
ivtv_udma_fill_sg_array (dma, ivtv_dest_addr, 0, -1);
/* Tag SG Array with Interrupt Bit */
dma->SGarray[dma->SG_length - 1].size |= cpu_to_le32(0x80000000);
ivtv_udma_sync_for_device(itv);
return dma->page_count;
}
void ivtv_udma_unmap(struct ivtv *itv)
{
struct ivtv_user_dma *dma = &itv->udma;
IVTV_DEBUG_INFO("ivtv_unmap_user_dma\n");
/* Nothing to free */
if (dma->page_count == 0)
return;
/* Unmap Scatterlist */
if (dma->SG_length) {
dma_unmap_sg(&itv->pdev->dev, dma->SGlist, dma->page_count,
DMA_TO_DEVICE);
dma->SG_length = 0;
}
/* sync DMA */
ivtv_udma_sync_for_cpu(itv);
unpin_user_pages(dma->map, dma->page_count);
dma->page_count = 0;
}
void ivtv_udma_free(struct ivtv *itv)
{
int i;
/* Unmap SG Array */
if (itv->udma.SG_handle) {
dma_unmap_single(&itv->pdev->dev, itv->udma.SG_handle,
sizeof(itv->udma.SGarray), DMA_TO_DEVICE);
}
/* Unmap Scatterlist */
if (itv->udma.SG_length) {
dma_unmap_sg(&itv->pdev->dev, itv->udma.SGlist,
itv->udma.page_count, DMA_TO_DEVICE);
}
for (i = 0; i < IVTV_DMA_SG_OSD_ENT; i++) {
if (itv->udma.bouncemap[i])
__free_page(itv->udma.bouncemap[i]);
}
}
void ivtv_udma_start(struct ivtv *itv)
{
IVTV_DEBUG_DMA("start UDMA\n");
write_reg(itv->udma.SG_handle, IVTV_REG_DECDMAADDR);
write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x01, IVTV_REG_DMAXFER);
set_bit(IVTV_F_I_DMA, &itv->i_flags);
set_bit(IVTV_F_I_UDMA, &itv->i_flags);
clear_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags);
}
void ivtv_udma_prepare(struct ivtv *itv)
{
unsigned long flags;
spin_lock_irqsave(&itv->dma_reg_lock, flags);
if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))
ivtv_udma_start(itv);
else
set_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags);
spin_unlock_irqrestore(&itv->dma_reg_lock, flags);
}
|
