1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Driver for the NXP SAA7164 PCIe bridge
4 *
5 *  Copyright (c) 2010-2015 Steven Toth <stoth@kernellabs.com>
6 */
7
8#include <linux/slab.h>
9
10#include "saa7164.h"
11
12/* The PCI address space for buffer handling looks like this:
13 *
14 * +-u32 wide-------------+
15 * |                      +
16 * +-u64 wide------------------------------------+
17 * +                                             +
18 * +----------------------+
19 * | CurrentBufferPtr     + Pointer to current PCI buffer >-+
20 * +----------------------+                                 |
21 * | Unused               +                                 |
22 * +----------------------+                                 |
23 * | Pitch                + = 188 (bytes)                   |
24 * +----------------------+                                 |
25 * | PCI buffer size      + = pitch * number of lines (312) |
26 * +----------------------+                                 |
27 * |0| Buf0 Write Offset  +                                 |
28 * +----------------------+                                 v
29 * |1| Buf1 Write Offset  +                                 |
30 * +----------------------+                                 |
31 * |2| Buf2 Write Offset  +                                 |
32 * +----------------------+                                 |
33 * |3| Buf3 Write Offset  +                                 |
34 * +----------------------+                                 |
35 * ... More write offsets                                   |
36 * +---------------------------------------------+          |
37 * +0| set of ptrs to PCI pagetables             +          |
38 * +---------------------------------------------+          |
39 * +1| set of ptrs to PCI pagetables             + <--------+
40 * +---------------------------------------------+
41 * +2| set of ptrs to PCI pagetables             +
42 * +---------------------------------------------+
43 * +3| set of ptrs to PCI pagetables             + >--+
44 * +---------------------------------------------+    |
45 * ... More buffer pointers                           |  +----------------+
46 *						    +->| pt[0] TS data  |
47 *						    |  +----------------+
48 *						    |
49 *						    |  +----------------+
50 *						    +->| pt[1] TS data  |
51 *						    |  +----------------+
52 *						    | etc
53 */
54
55void saa7164_buffer_display(struct saa7164_buffer *buf)
56{
57	struct saa7164_dev *dev = buf->port->dev;
58	int i;
59
60	dprintk(DBGLVL_BUF, "%s()   buffer @ 0x%p nr=%d\n",
61		__func__, buf, buf->idx);
62	dprintk(DBGLVL_BUF, "  pci_cpu @ 0x%p    dma @ 0x%08llx len = 0x%x\n",
63		buf->cpu, (long long)buf->dma, buf->pci_size);
64	dprintk(DBGLVL_BUF, "   pt_cpu @ 0x%p pt_dma @ 0x%08llx len = 0x%x\n",
65		buf->pt_cpu, (long long)buf->pt_dma, buf->pt_size);
66
67	/* Format the Page Table Entries to point into the data buffer */
68	for (i = 0 ; i < SAA7164_PT_ENTRIES; i++) {
69
70		dprintk(DBGLVL_BUF, "    pt[%02d] = 0x%p -> 0x%llx\n",
71			i, buf->pt_cpu, (u64)*(buf->pt_cpu));
72
73	}
74}
75/* Allocate a new buffer structure and associated PCI space in bytes.
76 * len must be a multiple of sizeof(u64)
77 */
78struct saa7164_buffer *saa7164_buffer_alloc(struct saa7164_port *port,
79	u32 len)
80{
81	struct tmHWStreamParameters *params = &port->hw_streamingparams;
82	struct saa7164_buffer *buf = NULL;
83	struct saa7164_dev *dev = port->dev;
84	int i;
85
86	if ((len == 0) || (len >= 65536) || (len % sizeof(u64))) {
87		log_warn("%s() SAA_ERR_BAD_PARAMETER\n", __func__);
88		goto ret;
89	}
90
91	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
92	if (!buf)
93		goto ret;
94
95	buf->idx = -1;
96	buf->port = port;
97	buf->flags = SAA7164_BUFFER_FREE;
98	buf->pos = 0;
99	buf->actual_size = params->pitch * params->numberoflines;
100	buf->crc = 0;
101	/* TODO: arg len is being ignored */
102	buf->pci_size = SAA7164_PT_ENTRIES * 0x1000;
103	buf->pt_size = (SAA7164_PT_ENTRIES * sizeof(u64)) + 0x1000;
104
105	/* Allocate contiguous memory */
106	buf->cpu = dma_alloc_coherent(&port->dev->pci->dev, buf->pci_size,
107				      &buf->dma, GFP_KERNEL);
108	if (!buf->cpu)
109		goto fail1;
110
111	buf->pt_cpu = dma_alloc_coherent(&port->dev->pci->dev, buf->pt_size,
112					 &buf->pt_dma, GFP_KERNEL);
113	if (!buf->pt_cpu)
114		goto fail2;
115
116	/* init the buffers to a known pattern, easier during debugging */
117	memset(buf->cpu, 0xff, buf->pci_size);
118	buf->crc = crc32(0, buf->cpu, buf->actual_size);
119	memset(buf->pt_cpu, 0xff, buf->pt_size);
120
121	dprintk(DBGLVL_BUF, "%s()   allocated buffer @ 0x%p (%d pageptrs)\n",
122		__func__, buf, params->numpagetables);
123	dprintk(DBGLVL_BUF, "  pci_cpu @ 0x%p    dma @ 0x%08lx len = 0x%x\n",
124		buf->cpu, (long)buf->dma, buf->pci_size);
125	dprintk(DBGLVL_BUF, "   pt_cpu @ 0x%p pt_dma @ 0x%08lx len = 0x%x\n",
126		buf->pt_cpu, (long)buf->pt_dma, buf->pt_size);
127
128	/* Format the Page Table Entries to point into the data buffer */
129	for (i = 0 ; i < params->numpagetables; i++) {
130
131		*(buf->pt_cpu + i) = buf->dma + (i * 0x1000); /* TODO */
132		dprintk(DBGLVL_BUF, "    pt[%02d] = 0x%p -> 0x%llx\n",
133			i, buf->pt_cpu, (u64)*(buf->pt_cpu));
134
135	}
136
137	goto ret;
138
139fail2:
140	dma_free_coherent(&port->dev->pci->dev, buf->pci_size, buf->cpu,
141			  buf->dma);
142fail1:
143	kfree(buf);
144
145	buf = NULL;
146ret:
147	return buf;
148}
149
150int saa7164_buffer_dealloc(struct saa7164_buffer *buf)
151{
152	struct saa7164_dev *dev;
153
154	if (!buf || !buf->port)
155		return SAA_ERR_BAD_PARAMETER;
156	dev = buf->port->dev;
157
158	dprintk(DBGLVL_BUF, "%s() deallocating buffer @ 0x%p\n",
159		__func__, buf);
160
161	if (buf->flags != SAA7164_BUFFER_FREE)
162		log_warn(" freeing a non-free buffer\n");
163
164	dma_free_coherent(&dev->pci->dev, buf->pci_size, buf->cpu, buf->dma);
165	dma_free_coherent(&dev->pci->dev, buf->pt_size, buf->pt_cpu,
166			  buf->pt_dma);
167
168	kfree(buf);
169
170	return SAA_OK;
171}
172
173int saa7164_buffer_zero_offsets(struct saa7164_port *port, int i)
174{
175	struct saa7164_dev *dev = port->dev;
176
177	if ((i < 0) || (i >= port->hwcfg.buffercount))
178		return -EINVAL;
179
180	dprintk(DBGLVL_BUF, "%s(idx = %d)\n", __func__, i);
181
182	saa7164_writel(port->bufoffset + (sizeof(u32) * i), 0);
183
184	return 0;
185}
186
187/* Write a buffer into the hardware */
188int saa7164_buffer_activate(struct saa7164_buffer *buf, int i)
189{
190	struct saa7164_port *port = buf->port;
191	struct saa7164_dev *dev = port->dev;
192
193	if ((i < 0) || (i >= port->hwcfg.buffercount))
194		return -EINVAL;
195
196	dprintk(DBGLVL_BUF, "%s(idx = %d)\n", __func__, i);
197
198	buf->idx = i; /* Note of which buffer list index position we occupy */
199	buf->flags = SAA7164_BUFFER_BUSY;
200	buf->pos = 0;
201
202	/* TODO: Review this in light of 32v64 assignments */
203	saa7164_writel(port->bufoffset + (sizeof(u32) * i), 0);
204	saa7164_writel(port->bufptr32h + ((sizeof(u32) * 2) * i), buf->pt_dma);
205	saa7164_writel(port->bufptr32l + ((sizeof(u32) * 2) * i), 0);
206
207	dprintk(DBGLVL_BUF, "	buf[%d] offset 0x%llx (0x%x) buf 0x%llx/%llx (0x%x/%x) nr=%d\n",
208		buf->idx,
209		(u64)port->bufoffset + (i * sizeof(u32)),
210		saa7164_readl(port->bufoffset + (sizeof(u32) * i)),
211		(u64)port->bufptr32h + ((sizeof(u32) * 2) * i),
212		(u64)port->bufptr32l + ((sizeof(u32) * 2) * i),
213		saa7164_readl(port->bufptr32h + ((sizeof(u32) * i) * 2)),
214		saa7164_readl(port->bufptr32l + ((sizeof(u32) * i) * 2)),
215		buf->idx);
216
217	return 0;
218}
219
220int saa7164_buffer_cfg_port(struct saa7164_port *port)
221{
222	struct tmHWStreamParameters *params = &port->hw_streamingparams;
223	struct saa7164_dev *dev = port->dev;
224	struct saa7164_buffer *buf;
225	struct list_head *c, *n;
226	int i = 0;
227
228	dprintk(DBGLVL_BUF, "%s(port=%d)\n", __func__, port->nr);
229
230	saa7164_writel(port->bufcounter, 0);
231	saa7164_writel(port->pitch, params->pitch);
232	saa7164_writel(port->bufsize, params->pitch * params->numberoflines);
233
234	dprintk(DBGLVL_BUF, " configured:\n");
235	dprintk(DBGLVL_BUF, "   lmmio       0x%p\n", dev->lmmio);
236	dprintk(DBGLVL_BUF, "   bufcounter  0x%x = 0x%x\n", port->bufcounter,
237		saa7164_readl(port->bufcounter));
238
239	dprintk(DBGLVL_BUF, "   pitch       0x%x = %d\n", port->pitch,
240		saa7164_readl(port->pitch));
241
242	dprintk(DBGLVL_BUF, "   bufsize     0x%x = %d\n", port->bufsize,
243		saa7164_readl(port->bufsize));
244
245	dprintk(DBGLVL_BUF, "   buffercount = %d\n", port->hwcfg.buffercount);
246	dprintk(DBGLVL_BUF, "   bufoffset = 0x%x\n", port->bufoffset);
247	dprintk(DBGLVL_BUF, "   bufptr32h = 0x%x\n", port->bufptr32h);
248	dprintk(DBGLVL_BUF, "   bufptr32l = 0x%x\n", port->bufptr32l);
249
250	/* Poke the buffers and offsets into PCI space */
251	mutex_lock(&port->dmaqueue_lock);
252	list_for_each_safe(c, n, &port->dmaqueue.list) {
253		buf = list_entry(c, struct saa7164_buffer, list);
254
255		BUG_ON(buf->flags != SAA7164_BUFFER_FREE);
256
257		/* Place the buffer in the h/w queue */
258		saa7164_buffer_activate(buf, i);
259
260		/* Don't exceed the device maximum # bufs */
261		BUG_ON(i > port->hwcfg.buffercount);
262		i++;
263
264	}
265	mutex_unlock(&port->dmaqueue_lock);
266
267	return 0;
268}
269
270struct saa7164_user_buffer *saa7164_buffer_alloc_user(struct saa7164_dev *dev,
271	u32 len)
272{
273	struct saa7164_user_buffer *buf;
274
275	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
276	if (!buf)
277		return NULL;
278
279	buf->data = kzalloc(len, GFP_KERNEL);
280
281	if (!buf->data) {
282		kfree(buf);
283		return NULL;
284	}
285
286	buf->actual_size = len;
287	buf->pos = 0;
288	buf->crc = 0;
289
290	dprintk(DBGLVL_BUF, "%s()   allocated user buffer @ 0x%p\n",
291		__func__, buf);
292
293	return buf;
294}
295
296void saa7164_buffer_dealloc_user(struct saa7164_user_buffer *buf)
297{
298	if (!buf)
299		return;
300
301	kfree(buf->data);
302	buf->data = NULL;
303
304	kfree(buf);
305}
306