1 /*
2  * Copyright (C) 2010-2013 Bluecherry, LLC <http://www.bluecherrydvr.com>
3  *
4  * Original author:
5  * Ben Collins <bcollins@ubuntu.com>
6  *
7  * Additional work by:
8  * John Brooks <john.brooks@bluecherry.net>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  */
20 
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/slab.h>
24 
25 #include "solo6x10.h"
26 
27 static int multi_p2m;
28 module_param(multi_p2m, uint, 0644);
29 MODULE_PARM_DESC(multi_p2m,
30 		 "Use multiple P2M DMA channels (default: no, 6010-only)");
31 
32 static int desc_mode;
33 module_param(desc_mode, uint, 0644);
34 MODULE_PARM_DESC(desc_mode,
35 		 "Allow use of descriptor mode DMA (default: no, 6010-only)");
36 
37 int solo_p2m_dma(struct solo_dev *solo_dev, int wr,
38 		 void *sys_addr, u32 ext_addr, u32 size,
39 		 int repeat, u32 ext_size)
40 {
41 	dma_addr_t dma_addr;
42 	int ret;
43 
44 	if (WARN_ON_ONCE((unsigned long)sys_addr & 0x03))
45 		return -EINVAL;
46 	if (WARN_ON_ONCE(!size))
47 		return -EINVAL;
48 
49 	dma_addr = pci_map_single(solo_dev->pdev, sys_addr, size,
50 				  wr ? PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
51 	if (pci_dma_mapping_error(solo_dev->pdev, dma_addr))
52 		return -ENOMEM;
53 
54 	ret = solo_p2m_dma_t(solo_dev, wr, dma_addr, ext_addr, size,
55 			     repeat, ext_size);
56 
57 	pci_unmap_single(solo_dev->pdev, dma_addr, size,
58 			 wr ? PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
59 
60 	return ret;
61 }
62 
63 /* Mutex must be held for p2m_id before calling this!! */
64 int solo_p2m_dma_desc(struct solo_dev *solo_dev,
65 		      struct solo_p2m_desc *desc, dma_addr_t desc_dma,
66 		      int desc_cnt)
67 {
68 	struct solo_p2m_dev *p2m_dev;
69 	unsigned int timeout;
70 	unsigned int config = 0;
71 	int ret = 0;
72 	int p2m_id = 0;
73 
74 	/* Get next ID. According to Softlogic, 6110 has problems on !=0 P2M */
75 	if (solo_dev->type != SOLO_DEV_6110 && multi_p2m) {
76 		p2m_id = atomic_inc_return(&solo_dev->p2m_count) % SOLO_NR_P2M;
77 		if (p2m_id < 0)
78 			p2m_id = -p2m_id;
79 	}
80 
81 	p2m_dev = &solo_dev->p2m_dev[p2m_id];
82 
83 	if (mutex_lock_interruptible(&p2m_dev->mutex))
84 		return -EINTR;
85 
86 	reinit_completion(&p2m_dev->completion);
87 	p2m_dev->error = 0;
88 
89 	if (desc_cnt > 1 && solo_dev->type != SOLO_DEV_6110 && desc_mode) {
90 		/* For 6010 with more than one desc, we can do a one-shot */
91 		p2m_dev->desc_count = p2m_dev->desc_idx = 0;
92 		config = solo_reg_read(solo_dev, SOLO_P2M_CONFIG(p2m_id));
93 
94 		solo_reg_write(solo_dev, SOLO_P2M_DES_ADR(p2m_id), desc_dma);
95 		solo_reg_write(solo_dev, SOLO_P2M_DESC_ID(p2m_id), desc_cnt);
96 		solo_reg_write(solo_dev, SOLO_P2M_CONFIG(p2m_id), config |
97 			       SOLO_P2M_DESC_MODE);
98 	} else {
99 		/* For single descriptors and 6110, we need to run each desc */
100 		p2m_dev->desc_count = desc_cnt;
101 		p2m_dev->desc_idx = 1;
102 		p2m_dev->descs = desc;
103 
104 		solo_reg_write(solo_dev, SOLO_P2M_TAR_ADR(p2m_id),
105 			       desc[1].dma_addr);
106 		solo_reg_write(solo_dev, SOLO_P2M_EXT_ADR(p2m_id),
107 			       desc[1].ext_addr);
108 		solo_reg_write(solo_dev, SOLO_P2M_EXT_CFG(p2m_id),
109 			       desc[1].cfg);
110 		solo_reg_write(solo_dev, SOLO_P2M_CONTROL(p2m_id),
111 			       desc[1].ctrl);
112 	}
113 
114 	timeout = wait_for_completion_timeout(&p2m_dev->completion,
115 					      solo_dev->p2m_jiffies);
116 
117 	if (WARN_ON_ONCE(p2m_dev->error))
118 		ret = -EIO;
119 	else if (timeout == 0) {
120 		solo_dev->p2m_timeouts++;
121 		ret = -EAGAIN;
122 	}
123 
124 	solo_reg_write(solo_dev, SOLO_P2M_CONTROL(p2m_id), 0);
125 
126 	/* Don't write here for the no_desc_mode case, because config is 0.
127 	 * We can't test no_desc_mode again, it might race. */
128 	if (desc_cnt > 1 && solo_dev->type != SOLO_DEV_6110 && config)
129 		solo_reg_write(solo_dev, SOLO_P2M_CONFIG(p2m_id), config);
130 
131 	mutex_unlock(&p2m_dev->mutex);
132 
133 	return ret;
134 }
135 
136 void solo_p2m_fill_desc(struct solo_p2m_desc *desc, int wr,
137 			dma_addr_t dma_addr, u32 ext_addr, u32 size,
138 			int repeat, u32 ext_size)
139 {
140 	WARN_ON_ONCE(dma_addr & 0x03);
141 	WARN_ON_ONCE(!size);
142 
143 	desc->cfg = SOLO_P2M_COPY_SIZE(size >> 2);
144 	desc->ctrl = SOLO_P2M_BURST_SIZE(SOLO_P2M_BURST_256) |
145 		(wr ? SOLO_P2M_WRITE : 0) | SOLO_P2M_TRANS_ON;
146 
147 	if (repeat) {
148 		desc->cfg |= SOLO_P2M_EXT_INC(ext_size >> 2);
149 		desc->ctrl |=  SOLO_P2M_PCI_INC(size >> 2) |
150 			 SOLO_P2M_REPEAT(repeat);
151 	}
152 
153 	desc->dma_addr = dma_addr;
154 	desc->ext_addr = ext_addr;
155 }
156 
157 int solo_p2m_dma_t(struct solo_dev *solo_dev, int wr,
158 		   dma_addr_t dma_addr, u32 ext_addr, u32 size,
159 		   int repeat, u32 ext_size)
160 {
161 	struct solo_p2m_desc desc[2];
162 
163 	solo_p2m_fill_desc(&desc[1], wr, dma_addr, ext_addr, size, repeat,
164 			   ext_size);
165 
166 	/* No need for desc_dma since we know it is a single-shot */
167 	return solo_p2m_dma_desc(solo_dev, desc, 0, 1);
168 }
169 
170 void solo_p2m_isr(struct solo_dev *solo_dev, int id)
171 {
172 	struct solo_p2m_dev *p2m_dev = &solo_dev->p2m_dev[id];
173 	struct solo_p2m_desc *desc;
174 
175 	if (p2m_dev->desc_count <= p2m_dev->desc_idx) {
176 		complete(&p2m_dev->completion);
177 		return;
178 	}
179 
180 	/* Setup next descriptor */
181 	p2m_dev->desc_idx++;
182 	desc = &p2m_dev->descs[p2m_dev->desc_idx];
183 
184 	solo_reg_write(solo_dev, SOLO_P2M_CONTROL(id), 0);
185 	solo_reg_write(solo_dev, SOLO_P2M_TAR_ADR(id), desc->dma_addr);
186 	solo_reg_write(solo_dev, SOLO_P2M_EXT_ADR(id), desc->ext_addr);
187 	solo_reg_write(solo_dev, SOLO_P2M_EXT_CFG(id), desc->cfg);
188 	solo_reg_write(solo_dev, SOLO_P2M_CONTROL(id), desc->ctrl);
189 }
190 
191 void solo_p2m_error_isr(struct solo_dev *solo_dev)
192 {
193 	unsigned int err = solo_reg_read(solo_dev, SOLO_PCI_ERR);
194 	struct solo_p2m_dev *p2m_dev;
195 	int i;
196 
197 	if (!(err & (SOLO_PCI_ERR_P2M | SOLO_PCI_ERR_P2M_DESC)))
198 		return;
199 
200 	for (i = 0; i < SOLO_NR_P2M; i++) {
201 		p2m_dev = &solo_dev->p2m_dev[i];
202 		p2m_dev->error = 1;
203 		solo_reg_write(solo_dev, SOLO_P2M_CONTROL(i), 0);
204 		complete(&p2m_dev->completion);
205 	}
206 }
207 
208 void solo_p2m_exit(struct solo_dev *solo_dev)
209 {
210 	int i;
211 
212 	for (i = 0; i < SOLO_NR_P2M; i++)
213 		solo_irq_off(solo_dev, SOLO_IRQ_P2M(i));
214 }
215 
216 static int solo_p2m_test(struct solo_dev *solo_dev, int base, int size)
217 {
218 	u32 *wr_buf;
219 	u32 *rd_buf;
220 	int i;
221 	int ret = -EIO;
222 	int order = get_order(size);
223 
224 	wr_buf = (u32 *)__get_free_pages(GFP_KERNEL, order);
225 	if (wr_buf == NULL)
226 		return -1;
227 
228 	rd_buf = (u32 *)__get_free_pages(GFP_KERNEL, order);
229 	if (rd_buf == NULL) {
230 		free_pages((unsigned long)wr_buf, order);
231 		return -1;
232 	}
233 
234 	for (i = 0; i < (size >> 3); i++)
235 		*(wr_buf + i) = (i << 16) | (i + 1);
236 
237 	for (i = (size >> 3); i < (size >> 2); i++)
238 		*(wr_buf + i) = ~((i << 16) | (i + 1));
239 
240 	memset(rd_buf, 0x55, size);
241 
242 	if (solo_p2m_dma(solo_dev, 1, wr_buf, base, size, 0, 0))
243 		goto test_fail;
244 
245 	if (solo_p2m_dma(solo_dev, 0, rd_buf, base, size, 0, 0))
246 		goto test_fail;
247 
248 	for (i = 0; i < (size >> 2); i++) {
249 		if (*(wr_buf + i) != *(rd_buf + i))
250 			goto test_fail;
251 	}
252 
253 	ret = 0;
254 
255 test_fail:
256 	free_pages((unsigned long)wr_buf, order);
257 	free_pages((unsigned long)rd_buf, order);
258 
259 	return ret;
260 }
261 
262 int solo_p2m_init(struct solo_dev *solo_dev)
263 {
264 	struct solo_p2m_dev *p2m_dev;
265 	int i;
266 
267 	for (i = 0; i < SOLO_NR_P2M; i++) {
268 		p2m_dev = &solo_dev->p2m_dev[i];
269 
270 		mutex_init(&p2m_dev->mutex);
271 		init_completion(&p2m_dev->completion);
272 
273 		solo_reg_write(solo_dev, SOLO_P2M_CONTROL(i), 0);
274 		solo_reg_write(solo_dev, SOLO_P2M_CONFIG(i),
275 			       SOLO_P2M_CSC_16BIT_565 |
276 			       SOLO_P2M_DESC_INTR_OPT |
277 			       SOLO_P2M_DMA_INTERVAL(0) |
278 			       SOLO_P2M_PCI_MASTER_MODE);
279 		solo_irq_on(solo_dev, SOLO_IRQ_P2M(i));
280 	}
281 
282 	/* Find correct SDRAM size */
283 	for (solo_dev->sdram_size = 0, i = 2; i >= 0; i--) {
284 		solo_reg_write(solo_dev, SOLO_DMA_CTRL,
285 			       SOLO_DMA_CTRL_REFRESH_CYCLE(1) |
286 			       SOLO_DMA_CTRL_SDRAM_SIZE(i) |
287 			       SOLO_DMA_CTRL_SDRAM_CLK_INVERT |
288 			       SOLO_DMA_CTRL_READ_CLK_SELECT |
289 			       SOLO_DMA_CTRL_LATENCY(1));
290 
291 		solo_reg_write(solo_dev, SOLO_SYS_CFG, solo_dev->sys_config |
292 			       SOLO_SYS_CFG_RESET);
293 		solo_reg_write(solo_dev, SOLO_SYS_CFG, solo_dev->sys_config);
294 
295 		switch (i) {
296 		case 2:
297 			if (solo_p2m_test(solo_dev, 0x07ff0000, 0x00010000) ||
298 			    solo_p2m_test(solo_dev, 0x05ff0000, 0x00010000))
299 				continue;
300 			break;
301 
302 		case 1:
303 			if (solo_p2m_test(solo_dev, 0x03ff0000, 0x00010000))
304 				continue;
305 			break;
306 
307 		default:
308 			if (solo_p2m_test(solo_dev, 0x01ff0000, 0x00010000))
309 				continue;
310 		}
311 
312 		solo_dev->sdram_size = (32 << 20) << i;
313 		break;
314 	}
315 
316 	if (!solo_dev->sdram_size) {
317 		dev_err(&solo_dev->pdev->dev, "Error detecting SDRAM size\n");
318 		return -EIO;
319 	}
320 
321 	if (SOLO_SDRAM_END(solo_dev) > solo_dev->sdram_size) {
322 		dev_err(&solo_dev->pdev->dev,
323 			"SDRAM is not large enough (%u < %u)\n",
324 			solo_dev->sdram_size, SOLO_SDRAM_END(solo_dev));
325 		return -EIO;
326 	}
327 
328 	return 0;
329 }
330