1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2010-2013 Bluecherry, LLC <https://www.bluecherrydvr.com>
4  *
5  * Original author:
6  * Ben Collins <bcollins@ubuntu.com>
7  *
8  * Additional work by:
9  * John Brooks <john.brooks@bluecherry.net>
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 
16 #include "solo6x10.h"
17 
18 static int multi_p2m;
19 module_param(multi_p2m, uint, 0644);
20 MODULE_PARM_DESC(multi_p2m,
21 		 "Use multiple P2M DMA channels (default: no, 6010-only)");
22 
23 static int desc_mode;
24 module_param(desc_mode, uint, 0644);
25 MODULE_PARM_DESC(desc_mode,
26 		 "Allow use of descriptor mode DMA (default: no, 6010-only)");
27 
28 int solo_p2m_dma(struct solo_dev *solo_dev, int wr,
29 		 void *sys_addr, u32 ext_addr, u32 size,
30 		 int repeat, u32 ext_size)
31 {
32 	dma_addr_t dma_addr;
33 	int ret;
34 
35 	if (WARN_ON_ONCE((unsigned long)sys_addr & 0x03))
36 		return -EINVAL;
37 	if (WARN_ON_ONCE(!size))
38 		return -EINVAL;
39 
40 	dma_addr = pci_map_single(solo_dev->pdev, sys_addr, size,
41 				  wr ? PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
42 	if (pci_dma_mapping_error(solo_dev->pdev, dma_addr))
43 		return -ENOMEM;
44 
45 	ret = solo_p2m_dma_t(solo_dev, wr, dma_addr, ext_addr, size,
46 			     repeat, ext_size);
47 
48 	pci_unmap_single(solo_dev->pdev, dma_addr, size,
49 			 wr ? PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
50 
51 	return ret;
52 }
53 
54 /* Mutex must be held for p2m_id before calling this!! */
55 int solo_p2m_dma_desc(struct solo_dev *solo_dev,
56 		      struct solo_p2m_desc *desc, dma_addr_t desc_dma,
57 		      int desc_cnt)
58 {
59 	struct solo_p2m_dev *p2m_dev;
60 	unsigned int timeout;
61 	unsigned int config = 0;
62 	int ret = 0;
63 	unsigned int p2m_id = 0;
64 
65 	/* Get next ID. According to Softlogic, 6110 has problems on !=0 P2M */
66 	if (solo_dev->type != SOLO_DEV_6110 && multi_p2m)
67 		p2m_id = atomic_inc_return(&solo_dev->p2m_count) % SOLO_NR_P2M;
68 
69 	p2m_dev = &solo_dev->p2m_dev[p2m_id];
70 
71 	if (mutex_lock_interruptible(&p2m_dev->mutex))
72 		return -EINTR;
73 
74 	reinit_completion(&p2m_dev->completion);
75 	p2m_dev->error = 0;
76 
77 	if (desc_cnt > 1 && solo_dev->type != SOLO_DEV_6110 && desc_mode) {
78 		/* For 6010 with more than one desc, we can do a one-shot */
79 		p2m_dev->desc_count = p2m_dev->desc_idx = 0;
80 		config = solo_reg_read(solo_dev, SOLO_P2M_CONFIG(p2m_id));
81 
82 		solo_reg_write(solo_dev, SOLO_P2M_DES_ADR(p2m_id), desc_dma);
83 		solo_reg_write(solo_dev, SOLO_P2M_DESC_ID(p2m_id), desc_cnt);
84 		solo_reg_write(solo_dev, SOLO_P2M_CONFIG(p2m_id), config |
85 			       SOLO_P2M_DESC_MODE);
86 	} else {
87 		/* For single descriptors and 6110, we need to run each desc */
88 		p2m_dev->desc_count = desc_cnt;
89 		p2m_dev->desc_idx = 1;
90 		p2m_dev->descs = desc;
91 
92 		solo_reg_write(solo_dev, SOLO_P2M_TAR_ADR(p2m_id),
93 			       desc[1].dma_addr);
94 		solo_reg_write(solo_dev, SOLO_P2M_EXT_ADR(p2m_id),
95 			       desc[1].ext_addr);
96 		solo_reg_write(solo_dev, SOLO_P2M_EXT_CFG(p2m_id),
97 			       desc[1].cfg);
98 		solo_reg_write(solo_dev, SOLO_P2M_CONTROL(p2m_id),
99 			       desc[1].ctrl);
100 	}
101 
102 	timeout = wait_for_completion_timeout(&p2m_dev->completion,
103 					      solo_dev->p2m_jiffies);
104 
105 	if (WARN_ON_ONCE(p2m_dev->error))
106 		ret = -EIO;
107 	else if (timeout == 0) {
108 		solo_dev->p2m_timeouts++;
109 		ret = -EAGAIN;
110 	}
111 
112 	solo_reg_write(solo_dev, SOLO_P2M_CONTROL(p2m_id), 0);
113 
114 	/* Don't write here for the no_desc_mode case, because config is 0.
115 	 * We can't test no_desc_mode again, it might race. */
116 	if (desc_cnt > 1 && solo_dev->type != SOLO_DEV_6110 && config)
117 		solo_reg_write(solo_dev, SOLO_P2M_CONFIG(p2m_id), config);
118 
119 	mutex_unlock(&p2m_dev->mutex);
120 
121 	return ret;
122 }
123 
124 void solo_p2m_fill_desc(struct solo_p2m_desc *desc, int wr,
125 			dma_addr_t dma_addr, u32 ext_addr, u32 size,
126 			int repeat, u32 ext_size)
127 {
128 	WARN_ON_ONCE(dma_addr & 0x03);
129 	WARN_ON_ONCE(!size);
130 
131 	desc->cfg = SOLO_P2M_COPY_SIZE(size >> 2);
132 	desc->ctrl = SOLO_P2M_BURST_SIZE(SOLO_P2M_BURST_256) |
133 		(wr ? SOLO_P2M_WRITE : 0) | SOLO_P2M_TRANS_ON;
134 
135 	if (repeat) {
136 		desc->cfg |= SOLO_P2M_EXT_INC(ext_size >> 2);
137 		desc->ctrl |=  SOLO_P2M_PCI_INC(size >> 2) |
138 			 SOLO_P2M_REPEAT(repeat);
139 	}
140 
141 	desc->dma_addr = dma_addr;
142 	desc->ext_addr = ext_addr;
143 }
144 
145 int solo_p2m_dma_t(struct solo_dev *solo_dev, int wr,
146 		   dma_addr_t dma_addr, u32 ext_addr, u32 size,
147 		   int repeat, u32 ext_size)
148 {
149 	struct solo_p2m_desc desc[2];
150 
151 	solo_p2m_fill_desc(&desc[1], wr, dma_addr, ext_addr, size, repeat,
152 			   ext_size);
153 
154 	/* No need for desc_dma since we know it is a single-shot */
155 	return solo_p2m_dma_desc(solo_dev, desc, 0, 1);
156 }
157 
158 void solo_p2m_isr(struct solo_dev *solo_dev, int id)
159 {
160 	struct solo_p2m_dev *p2m_dev = &solo_dev->p2m_dev[id];
161 	struct solo_p2m_desc *desc;
162 
163 	if (p2m_dev->desc_count <= p2m_dev->desc_idx) {
164 		complete(&p2m_dev->completion);
165 		return;
166 	}
167 
168 	/* Setup next descriptor */
169 	p2m_dev->desc_idx++;
170 	desc = &p2m_dev->descs[p2m_dev->desc_idx];
171 
172 	solo_reg_write(solo_dev, SOLO_P2M_CONTROL(id), 0);
173 	solo_reg_write(solo_dev, SOLO_P2M_TAR_ADR(id), desc->dma_addr);
174 	solo_reg_write(solo_dev, SOLO_P2M_EXT_ADR(id), desc->ext_addr);
175 	solo_reg_write(solo_dev, SOLO_P2M_EXT_CFG(id), desc->cfg);
176 	solo_reg_write(solo_dev, SOLO_P2M_CONTROL(id), desc->ctrl);
177 }
178 
179 void solo_p2m_error_isr(struct solo_dev *solo_dev)
180 {
181 	unsigned int err = solo_reg_read(solo_dev, SOLO_PCI_ERR);
182 	struct solo_p2m_dev *p2m_dev;
183 	int i;
184 
185 	if (!(err & (SOLO_PCI_ERR_P2M | SOLO_PCI_ERR_P2M_DESC)))
186 		return;
187 
188 	for (i = 0; i < SOLO_NR_P2M; i++) {
189 		p2m_dev = &solo_dev->p2m_dev[i];
190 		p2m_dev->error = 1;
191 		solo_reg_write(solo_dev, SOLO_P2M_CONTROL(i), 0);
192 		complete(&p2m_dev->completion);
193 	}
194 }
195 
196 void solo_p2m_exit(struct solo_dev *solo_dev)
197 {
198 	int i;
199 
200 	for (i = 0; i < SOLO_NR_P2M; i++)
201 		solo_irq_off(solo_dev, SOLO_IRQ_P2M(i));
202 }
203 
204 static int solo_p2m_test(struct solo_dev *solo_dev, int base, int size)
205 {
206 	u32 *wr_buf;
207 	u32 *rd_buf;
208 	int i;
209 	int ret = -EIO;
210 	int order = get_order(size);
211 
212 	wr_buf = (u32 *)__get_free_pages(GFP_KERNEL, order);
213 	if (wr_buf == NULL)
214 		return -1;
215 
216 	rd_buf = (u32 *)__get_free_pages(GFP_KERNEL, order);
217 	if (rd_buf == NULL) {
218 		free_pages((unsigned long)wr_buf, order);
219 		return -1;
220 	}
221 
222 	for (i = 0; i < (size >> 3); i++)
223 		*(wr_buf + i) = (i << 16) | (i + 1);
224 
225 	for (i = (size >> 3); i < (size >> 2); i++)
226 		*(wr_buf + i) = ~((i << 16) | (i + 1));
227 
228 	memset(rd_buf, 0x55, size);
229 
230 	if (solo_p2m_dma(solo_dev, 1, wr_buf, base, size, 0, 0))
231 		goto test_fail;
232 
233 	if (solo_p2m_dma(solo_dev, 0, rd_buf, base, size, 0, 0))
234 		goto test_fail;
235 
236 	for (i = 0; i < (size >> 2); i++) {
237 		if (*(wr_buf + i) != *(rd_buf + i))
238 			goto test_fail;
239 	}
240 
241 	ret = 0;
242 
243 test_fail:
244 	free_pages((unsigned long)wr_buf, order);
245 	free_pages((unsigned long)rd_buf, order);
246 
247 	return ret;
248 }
249 
250 int solo_p2m_init(struct solo_dev *solo_dev)
251 {
252 	struct solo_p2m_dev *p2m_dev;
253 	int i;
254 
255 	for (i = 0; i < SOLO_NR_P2M; i++) {
256 		p2m_dev = &solo_dev->p2m_dev[i];
257 
258 		mutex_init(&p2m_dev->mutex);
259 		init_completion(&p2m_dev->completion);
260 
261 		solo_reg_write(solo_dev, SOLO_P2M_CONTROL(i), 0);
262 		solo_reg_write(solo_dev, SOLO_P2M_CONFIG(i),
263 			       SOLO_P2M_CSC_16BIT_565 |
264 			       SOLO_P2M_DESC_INTR_OPT |
265 			       SOLO_P2M_DMA_INTERVAL(0) |
266 			       SOLO_P2M_PCI_MASTER_MODE);
267 		solo_irq_on(solo_dev, SOLO_IRQ_P2M(i));
268 	}
269 
270 	/* Find correct SDRAM size */
271 	for (solo_dev->sdram_size = 0, i = 2; i >= 0; i--) {
272 		solo_reg_write(solo_dev, SOLO_DMA_CTRL,
273 			       SOLO_DMA_CTRL_REFRESH_CYCLE(1) |
274 			       SOLO_DMA_CTRL_SDRAM_SIZE(i) |
275 			       SOLO_DMA_CTRL_SDRAM_CLK_INVERT |
276 			       SOLO_DMA_CTRL_READ_CLK_SELECT |
277 			       SOLO_DMA_CTRL_LATENCY(1));
278 
279 		solo_reg_write(solo_dev, SOLO_SYS_CFG, solo_dev->sys_config |
280 			       SOLO_SYS_CFG_RESET);
281 		solo_reg_write(solo_dev, SOLO_SYS_CFG, solo_dev->sys_config);
282 
283 		switch (i) {
284 		case 2:
285 			if (solo_p2m_test(solo_dev, 0x07ff0000, 0x00010000) ||
286 			    solo_p2m_test(solo_dev, 0x05ff0000, 0x00010000))
287 				continue;
288 			break;
289 
290 		case 1:
291 			if (solo_p2m_test(solo_dev, 0x03ff0000, 0x00010000))
292 				continue;
293 			break;
294 
295 		default:
296 			if (solo_p2m_test(solo_dev, 0x01ff0000, 0x00010000))
297 				continue;
298 		}
299 
300 		solo_dev->sdram_size = (32 << 20) << i;
301 		break;
302 	}
303 
304 	if (!solo_dev->sdram_size) {
305 		dev_err(&solo_dev->pdev->dev, "Error detecting SDRAM size\n");
306 		return -EIO;
307 	}
308 
309 	if (SOLO_SDRAM_END(solo_dev) > solo_dev->sdram_size) {
310 		dev_err(&solo_dev->pdev->dev,
311 			"SDRAM is not large enough (%u < %u)\n",
312 			solo_dev->sdram_size, SOLO_SDRAM_END(solo_dev));
313 		return -EIO;
314 	}
315 
316 	return 0;
317 }
318