xref: /linux/drivers/media/pci/saa7164/saa7164-buffer.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  *  Driver for the NXP SAA7164 PCIe bridge
3  *
4  *  Copyright (c) 2010-2015 Steven Toth <stoth@kernellabs.com>
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation; either version 2 of the License, or
9  *  (at your option) any later version.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 #include <linux/slab.h>
23 
24 #include "saa7164.h"
25 
26 /* The PCI address space for buffer handling looks like this:
27  *
28  * +-u32 wide-------------+
29  * |                      +
30  * +-u64 wide------------------------------------+
31  * +                                             +
32  * +----------------------+
33  * | CurrentBufferPtr     + Pointer to current PCI buffer >-+
34  * +----------------------+                                 |
35  * | Unused               +                                 |
36  * +----------------------+                                 |
37  * | Pitch                + = 188 (bytes)                   |
38  * +----------------------+                                 |
39  * | PCI buffer size      + = pitch * number of lines (312) |
40  * +----------------------+                                 |
41  * |0| Buf0 Write Offset  +                                 |
42  * +----------------------+                                 v
43  * |1| Buf1 Write Offset  +                                 |
44  * +----------------------+                                 |
45  * |2| Buf2 Write Offset  +                                 |
46  * +----------------------+                                 |
47  * |3| Buf3 Write Offset  +                                 |
48  * +----------------------+                                 |
49  * ... More write offsets                                   |
50  * +---------------------------------------------+          |
51  * +0| set of ptrs to PCI pagetables             +          |
52  * +---------------------------------------------+          |
53  * +1| set of ptrs to PCI pagetables             + <--------+
54  * +---------------------------------------------+
55  * +2| set of ptrs to PCI pagetables             +
56  * +---------------------------------------------+
57  * +3| set of ptrs to PCI pagetables             + >--+
58  * +---------------------------------------------+    |
59  * ... More buffer pointers                           |  +----------------+
60  *						    +->| pt[0] TS data  |
61  *						    |  +----------------+
62  *						    |
63  *						    |  +----------------+
64  *						    +->| pt[1] TS data  |
65  *						    |  +----------------+
66  *						    | etc
67  */
68 
69 void saa7164_buffer_display(struct saa7164_buffer *buf)
70 {
71 	struct saa7164_dev *dev = buf->port->dev;
72 	int i;
73 
74 	dprintk(DBGLVL_BUF, "%s()   buffer @ 0x%p nr=%d\n",
75 		__func__, buf, buf->idx);
76 	dprintk(DBGLVL_BUF, "  pci_cpu @ 0x%p    dma @ 0x%08llx len = 0x%x\n",
77 		buf->cpu, (long long)buf->dma, buf->pci_size);
78 	dprintk(DBGLVL_BUF, "   pt_cpu @ 0x%p pt_dma @ 0x%08llx len = 0x%x\n",
79 		buf->pt_cpu, (long long)buf->pt_dma, buf->pt_size);
80 
81 	/* Format the Page Table Entries to point into the data buffer */
82 	for (i = 0 ; i < SAA7164_PT_ENTRIES; i++) {
83 
84 		dprintk(DBGLVL_BUF, "    pt[%02d] = 0x%p -> 0x%llx\n",
85 			i, buf->pt_cpu, (u64)*(buf->pt_cpu));
86 
87 	}
88 }
89 /* Allocate a new buffer structure and associated PCI space in bytes.
90  * len must be a multiple of sizeof(u64)
91  */
92 struct saa7164_buffer *saa7164_buffer_alloc(struct saa7164_port *port,
93 	u32 len)
94 {
95 	struct tmHWStreamParameters *params = &port->hw_streamingparams;
96 	struct saa7164_buffer *buf = NULL;
97 	struct saa7164_dev *dev = port->dev;
98 	int i;
99 
100 	if ((len == 0) || (len >= 65536) || (len % sizeof(u64))) {
101 		log_warn("%s() SAA_ERR_BAD_PARAMETER\n", __func__);
102 		goto ret;
103 	}
104 
105 	buf = kzalloc(sizeof(struct saa7164_buffer), GFP_KERNEL);
106 	if (!buf) {
107 		log_warn("%s() SAA_ERR_NO_RESOURCES\n", __func__);
108 		goto ret;
109 	}
110 
111 	buf->idx = -1;
112 	buf->port = port;
113 	buf->flags = SAA7164_BUFFER_FREE;
114 	buf->pos = 0;
115 	buf->actual_size = params->pitch * params->numberoflines;
116 	buf->crc = 0;
117 	/* TODO: arg len is being ignored */
118 	buf->pci_size = SAA7164_PT_ENTRIES * 0x1000;
119 	buf->pt_size = (SAA7164_PT_ENTRIES * sizeof(u64)) + 0x1000;
120 
121 	/* Allocate contiguous memory */
122 	buf->cpu = pci_alloc_consistent(port->dev->pci, buf->pci_size,
123 		&buf->dma);
124 	if (!buf->cpu)
125 		goto fail1;
126 
127 	buf->pt_cpu = pci_alloc_consistent(port->dev->pci, buf->pt_size,
128 		&buf->pt_dma);
129 	if (!buf->pt_cpu)
130 		goto fail2;
131 
132 	/* init the buffers to a known pattern, easier during debugging */
133 	memset(buf->cpu, 0xff, buf->pci_size);
134 	buf->crc = crc32(0, buf->cpu, buf->actual_size);
135 	memset(buf->pt_cpu, 0xff, buf->pt_size);
136 
137 	dprintk(DBGLVL_BUF, "%s()   allocated buffer @ 0x%p (%d pageptrs)\n",
138 		__func__, buf, params->numpagetables);
139 	dprintk(DBGLVL_BUF, "  pci_cpu @ 0x%p    dma @ 0x%08lx len = 0x%x\n",
140 		buf->cpu, (long)buf->dma, buf->pci_size);
141 	dprintk(DBGLVL_BUF, "   pt_cpu @ 0x%p pt_dma @ 0x%08lx len = 0x%x\n",
142 		buf->pt_cpu, (long)buf->pt_dma, buf->pt_size);
143 
144 	/* Format the Page Table Entries to point into the data buffer */
145 	for (i = 0 ; i < params->numpagetables; i++) {
146 
147 		*(buf->pt_cpu + i) = buf->dma + (i * 0x1000); /* TODO */
148 		dprintk(DBGLVL_BUF, "    pt[%02d] = 0x%p -> 0x%llx\n",
149 			i, buf->pt_cpu, (u64)*(buf->pt_cpu));
150 
151 	}
152 
153 	goto ret;
154 
155 fail2:
156 	pci_free_consistent(port->dev->pci, buf->pci_size, buf->cpu, buf->dma);
157 fail1:
158 	kfree(buf);
159 
160 	buf = NULL;
161 ret:
162 	return buf;
163 }
164 
165 int saa7164_buffer_dealloc(struct saa7164_buffer *buf)
166 {
167 	struct saa7164_dev *dev;
168 
169 	if (!buf || !buf->port)
170 		return SAA_ERR_BAD_PARAMETER;
171 	dev = buf->port->dev;
172 
173 	dprintk(DBGLVL_BUF, "%s() deallocating buffer @ 0x%p\n",
174 		__func__, buf);
175 
176 	if (buf->flags != SAA7164_BUFFER_FREE)
177 		log_warn(" freeing a non-free buffer\n");
178 
179 	pci_free_consistent(dev->pci, buf->pci_size, buf->cpu, buf->dma);
180 	pci_free_consistent(dev->pci, buf->pt_size, buf->pt_cpu, buf->pt_dma);
181 
182 	kfree(buf);
183 
184 	return SAA_OK;
185 }
186 
187 int saa7164_buffer_zero_offsets(struct saa7164_port *port, int i)
188 {
189 	struct saa7164_dev *dev = port->dev;
190 
191 	if ((i < 0) || (i >= port->hwcfg.buffercount))
192 		return -EINVAL;
193 
194 	dprintk(DBGLVL_BUF, "%s(idx = %d)\n", __func__, i);
195 
196 	saa7164_writel(port->bufoffset + (sizeof(u32) * i), 0);
197 
198 	return 0;
199 }
200 
201 /* Write a buffer into the hardware */
202 int saa7164_buffer_activate(struct saa7164_buffer *buf, int i)
203 {
204 	struct saa7164_port *port = buf->port;
205 	struct saa7164_dev *dev = port->dev;
206 
207 	if ((i < 0) || (i >= port->hwcfg.buffercount))
208 		return -EINVAL;
209 
210 	dprintk(DBGLVL_BUF, "%s(idx = %d)\n", __func__, i);
211 
212 	buf->idx = i; /* Note of which buffer list index position we occupy */
213 	buf->flags = SAA7164_BUFFER_BUSY;
214 	buf->pos = 0;
215 
216 	/* TODO: Review this in light of 32v64 assignments */
217 	saa7164_writel(port->bufoffset + (sizeof(u32) * i), 0);
218 	saa7164_writel(port->bufptr32h + ((sizeof(u32) * 2) * i), buf->pt_dma);
219 	saa7164_writel(port->bufptr32l + ((sizeof(u32) * 2) * i), 0);
220 
221 	dprintk(DBGLVL_BUF, "   buf[%d] offset 0x%llx (0x%x) "
222 		"buf 0x%llx/%llx (0x%x/%x) nr=%d\n",
223 		buf->idx,
224 		(u64)port->bufoffset + (i * sizeof(u32)),
225 		saa7164_readl(port->bufoffset + (sizeof(u32) * i)),
226 		(u64)port->bufptr32h + ((sizeof(u32) * 2) * i),
227 		(u64)port->bufptr32l + ((sizeof(u32) * 2) * i),
228 		saa7164_readl(port->bufptr32h + ((sizeof(u32) * i) * 2)),
229 		saa7164_readl(port->bufptr32l + ((sizeof(u32) * i) * 2)),
230 		buf->idx);
231 
232 	return 0;
233 }
234 
235 int saa7164_buffer_cfg_port(struct saa7164_port *port)
236 {
237 	struct tmHWStreamParameters *params = &port->hw_streamingparams;
238 	struct saa7164_dev *dev = port->dev;
239 	struct saa7164_buffer *buf;
240 	struct list_head *c, *n;
241 	int i = 0;
242 
243 	dprintk(DBGLVL_BUF, "%s(port=%d)\n", __func__, port->nr);
244 
245 	saa7164_writel(port->bufcounter, 0);
246 	saa7164_writel(port->pitch, params->pitch);
247 	saa7164_writel(port->bufsize, params->pitch * params->numberoflines);
248 
249 	dprintk(DBGLVL_BUF, " configured:\n");
250 	dprintk(DBGLVL_BUF, "   lmmio       0x%p\n", dev->lmmio);
251 	dprintk(DBGLVL_BUF, "   bufcounter  0x%x = 0x%x\n", port->bufcounter,
252 		saa7164_readl(port->bufcounter));
253 
254 	dprintk(DBGLVL_BUF, "   pitch       0x%x = %d\n", port->pitch,
255 		saa7164_readl(port->pitch));
256 
257 	dprintk(DBGLVL_BUF, "   bufsize     0x%x = %d\n", port->bufsize,
258 		saa7164_readl(port->bufsize));
259 
260 	dprintk(DBGLVL_BUF, "   buffercount = %d\n", port->hwcfg.buffercount);
261 	dprintk(DBGLVL_BUF, "   bufoffset = 0x%x\n", port->bufoffset);
262 	dprintk(DBGLVL_BUF, "   bufptr32h = 0x%x\n", port->bufptr32h);
263 	dprintk(DBGLVL_BUF, "   bufptr32l = 0x%x\n", port->bufptr32l);
264 
265 	/* Poke the buffers and offsets into PCI space */
266 	mutex_lock(&port->dmaqueue_lock);
267 	list_for_each_safe(c, n, &port->dmaqueue.list) {
268 		buf = list_entry(c, struct saa7164_buffer, list);
269 
270 		if (buf->flags != SAA7164_BUFFER_FREE)
271 			BUG();
272 
273 		/* Place the buffer in the h/w queue */
274 		saa7164_buffer_activate(buf, i);
275 
276 		/* Don't exceed the device maximum # bufs */
277 		if (i++ > port->hwcfg.buffercount)
278 			BUG();
279 
280 	}
281 	mutex_unlock(&port->dmaqueue_lock);
282 
283 	return 0;
284 }
285 
286 struct saa7164_user_buffer *saa7164_buffer_alloc_user(struct saa7164_dev *dev,
287 	u32 len)
288 {
289 	struct saa7164_user_buffer *buf;
290 
291 	buf = kzalloc(sizeof(struct saa7164_user_buffer), GFP_KERNEL);
292 	if (!buf)
293 		return NULL;
294 
295 	buf->data = kzalloc(len, GFP_KERNEL);
296 
297 	if (!buf->data) {
298 		kfree(buf);
299 		return NULL;
300 	}
301 
302 	buf->actual_size = len;
303 	buf->pos = 0;
304 	buf->crc = 0;
305 
306 	dprintk(DBGLVL_BUF, "%s()   allocated user buffer @ 0x%p\n",
307 		__func__, buf);
308 
309 	return buf;
310 }
311 
312 void saa7164_buffer_dealloc_user(struct saa7164_user_buffer *buf)
313 {
314 	if (!buf)
315 		return;
316 
317 	kfree(buf->data);
318 	buf->data = NULL;
319 
320 	kfree(buf);
321 }
322 
323