xref: /linux/drivers/dma/ti/dma-crossbar.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com
4  *  Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
5  */
6 #include <linux/slab.h>
7 #include <linux/err.h>
8 #include <linux/init.h>
9 #include <linux/list.h>
10 #include <linux/io.h>
11 #include <linux/of_address.h>
12 #include <linux/of_device.h>
13 #include <linux/of_dma.h>
14 
15 #define TI_XBAR_DRA7		0
16 #define TI_XBAR_AM335X		1
17 static const u32 ti_xbar_type[] = {
18 	[TI_XBAR_DRA7] = TI_XBAR_DRA7,
19 	[TI_XBAR_AM335X] = TI_XBAR_AM335X,
20 };
21 
22 static const struct of_device_id ti_dma_xbar_match[] = {
23 	{
24 		.compatible = "ti,dra7-dma-crossbar",
25 		.data = &ti_xbar_type[TI_XBAR_DRA7],
26 	},
27 	{
28 		.compatible = "ti,am335x-edma-crossbar",
29 		.data = &ti_xbar_type[TI_XBAR_AM335X],
30 	},
31 	{},
32 };
33 
34 /* Crossbar on AM335x/AM437x family */
35 #define TI_AM335X_XBAR_LINES	64
36 
37 struct ti_am335x_xbar_data {
38 	void __iomem *iomem;
39 
40 	struct dma_router dmarouter;
41 
42 	u32 xbar_events; /* maximum number of events to select in xbar */
43 	u32 dma_requests; /* number of DMA requests on eDMA */
44 };
45 
46 struct ti_am335x_xbar_map {
47 	u16 dma_line;
48 	u8 mux_val;
49 };
50 
51 static inline void ti_am335x_xbar_write(void __iomem *iomem, int event, u8 val)
52 {
53 	/*
54 	 * TPCC_EVT_MUX_60_63 register layout is different than the
55 	 * rest, in the sense, that event 63 is mapped to lowest byte
56 	 * and event 60 is mapped to highest, handle it separately.
57 	 */
58 	if (event >= 60 && event <= 63)
59 		writeb_relaxed(val, iomem + (63 - event % 4));
60 	else
61 		writeb_relaxed(val, iomem + event);
62 }
63 
64 static void ti_am335x_xbar_free(struct device *dev, void *route_data)
65 {
66 	struct ti_am335x_xbar_data *xbar = dev_get_drvdata(dev);
67 	struct ti_am335x_xbar_map *map = route_data;
68 
69 	dev_dbg(dev, "Unmapping XBAR event %u on channel %u\n",
70 		map->mux_val, map->dma_line);
71 
72 	ti_am335x_xbar_write(xbar->iomem, map->dma_line, 0);
73 	kfree(map);
74 }
75 
76 static void *ti_am335x_xbar_route_allocate(struct of_phandle_args *dma_spec,
77 					   struct of_dma *ofdma)
78 {
79 	struct platform_device *pdev = of_find_device_by_node(ofdma->of_node);
80 	struct ti_am335x_xbar_data *xbar = platform_get_drvdata(pdev);
81 	struct ti_am335x_xbar_map *map;
82 
83 	if (dma_spec->args_count != 3)
84 		return ERR_PTR(-EINVAL);
85 
86 	if (dma_spec->args[2] >= xbar->xbar_events) {
87 		dev_err(&pdev->dev, "Invalid XBAR event number: %d\n",
88 			dma_spec->args[2]);
89 		return ERR_PTR(-EINVAL);
90 	}
91 
92 	if (dma_spec->args[0] >= xbar->dma_requests) {
93 		dev_err(&pdev->dev, "Invalid DMA request line number: %d\n",
94 			dma_spec->args[0]);
95 		return ERR_PTR(-EINVAL);
96 	}
97 
98 	/* The of_node_put() will be done in the core for the node */
99 	dma_spec->np = of_parse_phandle(ofdma->of_node, "dma-masters", 0);
100 	if (!dma_spec->np) {
101 		dev_err(&pdev->dev, "Can't get DMA master\n");
102 		return ERR_PTR(-EINVAL);
103 	}
104 
105 	map = kzalloc(sizeof(*map), GFP_KERNEL);
106 	if (!map) {
107 		of_node_put(dma_spec->np);
108 		return ERR_PTR(-ENOMEM);
109 	}
110 
111 	map->dma_line = (u16)dma_spec->args[0];
112 	map->mux_val = (u8)dma_spec->args[2];
113 
114 	dma_spec->args[2] = 0;
115 	dma_spec->args_count = 2;
116 
117 	dev_dbg(&pdev->dev, "Mapping XBAR event%u to DMA%u\n",
118 		map->mux_val, map->dma_line);
119 
120 	ti_am335x_xbar_write(xbar->iomem, map->dma_line, map->mux_val);
121 
122 	return map;
123 }
124 
125 static const struct of_device_id ti_am335x_master_match[] = {
126 	{ .compatible = "ti,edma3-tpcc", },
127 	{},
128 };
129 
130 static int ti_am335x_xbar_probe(struct platform_device *pdev)
131 {
132 	struct device_node *node = pdev->dev.of_node;
133 	const struct of_device_id *match;
134 	struct device_node *dma_node;
135 	struct ti_am335x_xbar_data *xbar;
136 	struct resource *res;
137 	void __iomem *iomem;
138 	int i, ret;
139 
140 	if (!node)
141 		return -ENODEV;
142 
143 	xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL);
144 	if (!xbar)
145 		return -ENOMEM;
146 
147 	dma_node = of_parse_phandle(node, "dma-masters", 0);
148 	if (!dma_node) {
149 		dev_err(&pdev->dev, "Can't get DMA master node\n");
150 		return -ENODEV;
151 	}
152 
153 	match = of_match_node(ti_am335x_master_match, dma_node);
154 	if (!match) {
155 		dev_err(&pdev->dev, "DMA master is not supported\n");
156 		of_node_put(dma_node);
157 		return -EINVAL;
158 	}
159 
160 	if (of_property_read_u32(dma_node, "dma-requests",
161 				 &xbar->dma_requests)) {
162 		dev_info(&pdev->dev,
163 			 "Missing XBAR output information, using %u.\n",
164 			 TI_AM335X_XBAR_LINES);
165 		xbar->dma_requests = TI_AM335X_XBAR_LINES;
166 	}
167 	of_node_put(dma_node);
168 
169 	if (of_property_read_u32(node, "dma-requests", &xbar->xbar_events)) {
170 		dev_info(&pdev->dev,
171 			 "Missing XBAR input information, using %u.\n",
172 			 TI_AM335X_XBAR_LINES);
173 		xbar->xbar_events = TI_AM335X_XBAR_LINES;
174 	}
175 
176 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
177 	iomem = devm_ioremap_resource(&pdev->dev, res);
178 	if (IS_ERR(iomem))
179 		return PTR_ERR(iomem);
180 
181 	xbar->iomem = iomem;
182 
183 	xbar->dmarouter.dev = &pdev->dev;
184 	xbar->dmarouter.route_free = ti_am335x_xbar_free;
185 
186 	platform_set_drvdata(pdev, xbar);
187 
188 	/* Reset the crossbar */
189 	for (i = 0; i < xbar->dma_requests; i++)
190 		ti_am335x_xbar_write(xbar->iomem, i, 0);
191 
192 	ret = of_dma_router_register(node, ti_am335x_xbar_route_allocate,
193 				     &xbar->dmarouter);
194 
195 	return ret;
196 }
197 
198 /* Crossbar on DRA7xx family */
199 #define TI_DRA7_XBAR_OUTPUTS	127
200 #define TI_DRA7_XBAR_INPUTS	256
201 
202 struct ti_dra7_xbar_data {
203 	void __iomem *iomem;
204 
205 	struct dma_router dmarouter;
206 	struct mutex mutex;
207 	unsigned long *dma_inuse;
208 
209 	u16 safe_val; /* Value to rest the crossbar lines */
210 	u32 xbar_requests; /* number of DMA requests connected to XBAR */
211 	u32 dma_requests; /* number of DMA requests forwarded to DMA */
212 	u32 dma_offset;
213 };
214 
215 struct ti_dra7_xbar_map {
216 	u16 xbar_in;
217 	int xbar_out;
218 };
219 
220 static inline void ti_dra7_xbar_write(void __iomem *iomem, int xbar, u16 val)
221 {
222 	writew_relaxed(val, iomem + (xbar * 2));
223 }
224 
225 static void ti_dra7_xbar_free(struct device *dev, void *route_data)
226 {
227 	struct ti_dra7_xbar_data *xbar = dev_get_drvdata(dev);
228 	struct ti_dra7_xbar_map *map = route_data;
229 
230 	dev_dbg(dev, "Unmapping XBAR%u (was routed to %d)\n",
231 		map->xbar_in, map->xbar_out);
232 
233 	ti_dra7_xbar_write(xbar->iomem, map->xbar_out, xbar->safe_val);
234 	mutex_lock(&xbar->mutex);
235 	clear_bit(map->xbar_out, xbar->dma_inuse);
236 	mutex_unlock(&xbar->mutex);
237 	kfree(map);
238 }
239 
240 static void *ti_dra7_xbar_route_allocate(struct of_phandle_args *dma_spec,
241 					 struct of_dma *ofdma)
242 {
243 	struct platform_device *pdev = of_find_device_by_node(ofdma->of_node);
244 	struct ti_dra7_xbar_data *xbar = platform_get_drvdata(pdev);
245 	struct ti_dra7_xbar_map *map;
246 
247 	if (dma_spec->args[0] >= xbar->xbar_requests) {
248 		dev_err(&pdev->dev, "Invalid XBAR request number: %d\n",
249 			dma_spec->args[0]);
250 		return ERR_PTR(-EINVAL);
251 	}
252 
253 	/* The of_node_put() will be done in the core for the node */
254 	dma_spec->np = of_parse_phandle(ofdma->of_node, "dma-masters", 0);
255 	if (!dma_spec->np) {
256 		dev_err(&pdev->dev, "Can't get DMA master\n");
257 		return ERR_PTR(-EINVAL);
258 	}
259 
260 	map = kzalloc(sizeof(*map), GFP_KERNEL);
261 	if (!map) {
262 		of_node_put(dma_spec->np);
263 		return ERR_PTR(-ENOMEM);
264 	}
265 
266 	mutex_lock(&xbar->mutex);
267 	map->xbar_out = find_first_zero_bit(xbar->dma_inuse,
268 					    xbar->dma_requests);
269 	if (map->xbar_out == xbar->dma_requests) {
270 		mutex_unlock(&xbar->mutex);
271 		dev_err(&pdev->dev, "Run out of free DMA requests\n");
272 		kfree(map);
273 		return ERR_PTR(-ENOMEM);
274 	}
275 	set_bit(map->xbar_out, xbar->dma_inuse);
276 	mutex_unlock(&xbar->mutex);
277 
278 	map->xbar_in = (u16)dma_spec->args[0];
279 
280 	dma_spec->args[0] = map->xbar_out + xbar->dma_offset;
281 
282 	dev_dbg(&pdev->dev, "Mapping XBAR%u to DMA%d\n",
283 		map->xbar_in, map->xbar_out);
284 
285 	ti_dra7_xbar_write(xbar->iomem, map->xbar_out, map->xbar_in);
286 
287 	return map;
288 }
289 
290 #define TI_XBAR_EDMA_OFFSET	0
291 #define TI_XBAR_SDMA_OFFSET	1
292 static const u32 ti_dma_offset[] = {
293 	[TI_XBAR_EDMA_OFFSET] = 0,
294 	[TI_XBAR_SDMA_OFFSET] = 1,
295 };
296 
297 static const struct of_device_id ti_dra7_master_match[] = {
298 	{
299 		.compatible = "ti,omap4430-sdma",
300 		.data = &ti_dma_offset[TI_XBAR_SDMA_OFFSET],
301 	},
302 	{
303 		.compatible = "ti,edma3",
304 		.data = &ti_dma_offset[TI_XBAR_EDMA_OFFSET],
305 	},
306 	{
307 		.compatible = "ti,edma3-tpcc",
308 		.data = &ti_dma_offset[TI_XBAR_EDMA_OFFSET],
309 	},
310 	{},
311 };
312 
313 static inline void ti_dra7_xbar_reserve(int offset, int len, unsigned long *p)
314 {
315 	for (; len > 0; len--)
316 		set_bit(offset + (len - 1), p);
317 }
318 
319 static int ti_dra7_xbar_probe(struct platform_device *pdev)
320 {
321 	struct device_node *node = pdev->dev.of_node;
322 	const struct of_device_id *match;
323 	struct device_node *dma_node;
324 	struct ti_dra7_xbar_data *xbar;
325 	struct property *prop;
326 	struct resource *res;
327 	u32 safe_val;
328 	int sz;
329 	void __iomem *iomem;
330 	int i, ret;
331 
332 	if (!node)
333 		return -ENODEV;
334 
335 	xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL);
336 	if (!xbar)
337 		return -ENOMEM;
338 
339 	dma_node = of_parse_phandle(node, "dma-masters", 0);
340 	if (!dma_node) {
341 		dev_err(&pdev->dev, "Can't get DMA master node\n");
342 		return -ENODEV;
343 	}
344 
345 	match = of_match_node(ti_dra7_master_match, dma_node);
346 	if (!match) {
347 		dev_err(&pdev->dev, "DMA master is not supported\n");
348 		of_node_put(dma_node);
349 		return -EINVAL;
350 	}
351 
352 	if (of_property_read_u32(dma_node, "dma-requests",
353 				 &xbar->dma_requests)) {
354 		dev_info(&pdev->dev,
355 			 "Missing XBAR output information, using %u.\n",
356 			 TI_DRA7_XBAR_OUTPUTS);
357 		xbar->dma_requests = TI_DRA7_XBAR_OUTPUTS;
358 	}
359 	of_node_put(dma_node);
360 
361 	xbar->dma_inuse = devm_kcalloc(&pdev->dev,
362 				       BITS_TO_LONGS(xbar->dma_requests),
363 				       sizeof(unsigned long), GFP_KERNEL);
364 	if (!xbar->dma_inuse)
365 		return -ENOMEM;
366 
367 	if (of_property_read_u32(node, "dma-requests", &xbar->xbar_requests)) {
368 		dev_info(&pdev->dev,
369 			 "Missing XBAR input information, using %u.\n",
370 			 TI_DRA7_XBAR_INPUTS);
371 		xbar->xbar_requests = TI_DRA7_XBAR_INPUTS;
372 	}
373 
374 	if (!of_property_read_u32(node, "ti,dma-safe-map", &safe_val))
375 		xbar->safe_val = (u16)safe_val;
376 
377 
378 	prop = of_find_property(node, "ti,reserved-dma-request-ranges", &sz);
379 	if (prop) {
380 		const char pname[] = "ti,reserved-dma-request-ranges";
381 		u32 (*rsv_events)[2];
382 		size_t nelm = sz / sizeof(*rsv_events);
383 		int i;
384 
385 		if (!nelm)
386 			return -EINVAL;
387 
388 		rsv_events = kcalloc(nelm, sizeof(*rsv_events), GFP_KERNEL);
389 		if (!rsv_events)
390 			return -ENOMEM;
391 
392 		ret = of_property_read_u32_array(node, pname, (u32 *)rsv_events,
393 						 nelm * 2);
394 		if (ret) {
395 			kfree(rsv_events);
396 			return ret;
397 		}
398 
399 		for (i = 0; i < nelm; i++) {
400 			ti_dra7_xbar_reserve(rsv_events[i][0], rsv_events[i][1],
401 					     xbar->dma_inuse);
402 		}
403 		kfree(rsv_events);
404 	}
405 
406 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
407 	iomem = devm_ioremap_resource(&pdev->dev, res);
408 	if (IS_ERR(iomem))
409 		return PTR_ERR(iomem);
410 
411 	xbar->iomem = iomem;
412 
413 	xbar->dmarouter.dev = &pdev->dev;
414 	xbar->dmarouter.route_free = ti_dra7_xbar_free;
415 	xbar->dma_offset = *(u32 *)match->data;
416 
417 	mutex_init(&xbar->mutex);
418 	platform_set_drvdata(pdev, xbar);
419 
420 	/* Reset the crossbar */
421 	for (i = 0; i < xbar->dma_requests; i++) {
422 		if (!test_bit(i, xbar->dma_inuse))
423 			ti_dra7_xbar_write(xbar->iomem, i, xbar->safe_val);
424 	}
425 
426 	ret = of_dma_router_register(node, ti_dra7_xbar_route_allocate,
427 				     &xbar->dmarouter);
428 	if (ret) {
429 		/* Restore the defaults for the crossbar */
430 		for (i = 0; i < xbar->dma_requests; i++) {
431 			if (!test_bit(i, xbar->dma_inuse))
432 				ti_dra7_xbar_write(xbar->iomem, i, i);
433 		}
434 	}
435 
436 	return ret;
437 }
438 
439 static int ti_dma_xbar_probe(struct platform_device *pdev)
440 {
441 	const struct of_device_id *match;
442 	int ret;
443 
444 	match = of_match_node(ti_dma_xbar_match, pdev->dev.of_node);
445 	if (unlikely(!match))
446 		return -EINVAL;
447 
448 	switch (*(u32 *)match->data) {
449 	case TI_XBAR_DRA7:
450 		ret = ti_dra7_xbar_probe(pdev);
451 		break;
452 	case TI_XBAR_AM335X:
453 		ret = ti_am335x_xbar_probe(pdev);
454 		break;
455 	default:
456 		dev_err(&pdev->dev, "Unsupported crossbar\n");
457 		ret = -ENODEV;
458 		break;
459 	}
460 
461 	return ret;
462 }
463 
464 static struct platform_driver ti_dma_xbar_driver = {
465 	.driver = {
466 		.name = "ti-dma-crossbar",
467 		.of_match_table = of_match_ptr(ti_dma_xbar_match),
468 	},
469 	.probe	= ti_dma_xbar_probe,
470 };
471 
472 static int omap_dmaxbar_init(void)
473 {
474 	return platform_driver_register(&ti_dma_xbar_driver);
475 }
476 arch_initcall(omap_dmaxbar_init);
477