xref: /linux/drivers/fpga/stratix10-soc.c (revision 06d07429858317ded2db7986113a9e0129cd599b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * FPGA Manager Driver for Intel Stratix10 SoC
4  *
5  *  Copyright (C) 2018 Intel Corporation
6  */
7 #include <linux/completion.h>
8 #include <linux/fpga/fpga-mgr.h>
9 #include <linux/firmware/intel/stratix10-svc-client.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/of_platform.h>
13 #include <linux/platform_device.h>
14 
15 /*
16  * FPGA programming requires a higher level of privilege (EL3), per the SoC
17  * design.
18  */
19 #define NUM_SVC_BUFS	4
20 #define SVC_BUF_SIZE	SZ_512K
21 
22 /* Indicates buffer is in use if set */
23 #define SVC_BUF_LOCK	0
24 
25 #define S10_BUFFER_TIMEOUT (msecs_to_jiffies(SVC_RECONFIG_BUFFER_TIMEOUT_MS))
26 #define S10_RECONFIG_TIMEOUT (msecs_to_jiffies(SVC_RECONFIG_REQUEST_TIMEOUT_MS))
27 
28 /*
29  * struct s10_svc_buf
30  * buf:  virtual address of buf provided by service layer
31  * lock: locked if buffer is in use
32  */
33 struct s10_svc_buf {
34 	char *buf;
35 	unsigned long lock;
36 };
37 
38 struct s10_priv {
39 	struct stratix10_svc_chan *chan;
40 	struct stratix10_svc_client client;
41 	struct completion status_return_completion;
42 	struct s10_svc_buf svc_bufs[NUM_SVC_BUFS];
43 	unsigned long status;
44 };
45 
s10_svc_send_msg(struct s10_priv * priv,enum stratix10_svc_command_code command,void * payload,u32 payload_length)46 static int s10_svc_send_msg(struct s10_priv *priv,
47 			    enum stratix10_svc_command_code command,
48 			    void *payload, u32 payload_length)
49 {
50 	struct stratix10_svc_chan *chan = priv->chan;
51 	struct device *dev = priv->client.dev;
52 	struct stratix10_svc_client_msg msg;
53 	int ret;
54 
55 	dev_dbg(dev, "%s cmd=%d payload=%p length=%d\n",
56 		__func__, command, payload, payload_length);
57 
58 	msg.command = command;
59 	msg.payload = payload;
60 	msg.payload_length = payload_length;
61 
62 	ret = stratix10_svc_send(chan, &msg);
63 	dev_dbg(dev, "stratix10_svc_send returned status %d\n", ret);
64 
65 	return ret;
66 }
67 
68 /*
69  * Free buffers allocated from the service layer's pool that are not in use.
70  * Return true when all buffers are freed.
71  */
s10_free_buffers(struct fpga_manager * mgr)72 static bool s10_free_buffers(struct fpga_manager *mgr)
73 {
74 	struct s10_priv *priv = mgr->priv;
75 	uint num_free = 0;
76 	uint i;
77 
78 	for (i = 0; i < NUM_SVC_BUFS; i++) {
79 		if (!priv->svc_bufs[i].buf) {
80 			num_free++;
81 			continue;
82 		}
83 
84 		if (!test_and_set_bit_lock(SVC_BUF_LOCK,
85 					   &priv->svc_bufs[i].lock)) {
86 			stratix10_svc_free_memory(priv->chan,
87 						  priv->svc_bufs[i].buf);
88 			priv->svc_bufs[i].buf = NULL;
89 			num_free++;
90 		}
91 	}
92 
93 	return num_free == NUM_SVC_BUFS;
94 }
95 
96 /*
97  * Returns count of how many buffers are not in use.
98  */
s10_free_buffer_count(struct fpga_manager * mgr)99 static uint s10_free_buffer_count(struct fpga_manager *mgr)
100 {
101 	struct s10_priv *priv = mgr->priv;
102 	uint num_free = 0;
103 	uint i;
104 
105 	for (i = 0; i < NUM_SVC_BUFS; i++)
106 		if (!priv->svc_bufs[i].buf)
107 			num_free++;
108 
109 	return num_free;
110 }
111 
112 /*
113  * s10_unlock_bufs
114  * Given the returned buffer address, match that address to our buffer struct
115  * and unlock that buffer.  This marks it as available to be refilled and sent
116  * (or freed).
117  * priv: private data
118  * kaddr: kernel address of buffer that was returned from service layer
119  */
s10_unlock_bufs(struct s10_priv * priv,void * kaddr)120 static void s10_unlock_bufs(struct s10_priv *priv, void *kaddr)
121 {
122 	uint i;
123 
124 	if (!kaddr)
125 		return;
126 
127 	for (i = 0; i < NUM_SVC_BUFS; i++)
128 		if (priv->svc_bufs[i].buf == kaddr) {
129 			clear_bit_unlock(SVC_BUF_LOCK,
130 					 &priv->svc_bufs[i].lock);
131 			return;
132 		}
133 
134 	WARN(1, "Unknown buffer returned from service layer %p\n", kaddr);
135 }
136 
137 /*
138  * s10_receive_callback - callback for service layer to use to provide client
139  * (this driver) messages received through the mailbox.
140  * client: service layer client struct
141  * data: message from service layer
142  */
s10_receive_callback(struct stratix10_svc_client * client,struct stratix10_svc_cb_data * data)143 static void s10_receive_callback(struct stratix10_svc_client *client,
144 				 struct stratix10_svc_cb_data *data)
145 {
146 	struct s10_priv *priv = client->priv;
147 	u32 status;
148 	int i;
149 
150 	WARN_ONCE(!data, "%s: stratix10_svc_rc_data = NULL", __func__);
151 
152 	status = data->status;
153 
154 	/*
155 	 * Here we set status bits as we receive them.  Elsewhere, we always use
156 	 * test_and_clear_bit() to check status in priv->status
157 	 */
158 	for (i = 0; i <= SVC_STATUS_ERROR; i++)
159 		if (status & (1 << i))
160 			set_bit(i, &priv->status);
161 
162 	if (status & BIT(SVC_STATUS_BUFFER_DONE)) {
163 		s10_unlock_bufs(priv, data->kaddr1);
164 		s10_unlock_bufs(priv, data->kaddr2);
165 		s10_unlock_bufs(priv, data->kaddr3);
166 	}
167 
168 	complete(&priv->status_return_completion);
169 }
170 
171 /*
172  * s10_ops_write_init - prepare for FPGA reconfiguration by requesting
173  * partial reconfig and allocating buffers from the service layer.
174  */
s10_ops_write_init(struct fpga_manager * mgr,struct fpga_image_info * info,const char * buf,size_t count)175 static int s10_ops_write_init(struct fpga_manager *mgr,
176 			      struct fpga_image_info *info,
177 			      const char *buf, size_t count)
178 {
179 	struct s10_priv *priv = mgr->priv;
180 	struct device *dev = priv->client.dev;
181 	struct stratix10_svc_command_config_type ctype;
182 	char *kbuf;
183 	uint i;
184 	int ret;
185 
186 	ctype.flags = 0;
187 	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
188 		dev_dbg(dev, "Requesting partial reconfiguration.\n");
189 		ctype.flags |= BIT(COMMAND_RECONFIG_FLAG_PARTIAL);
190 	} else {
191 		dev_dbg(dev, "Requesting full reconfiguration.\n");
192 	}
193 
194 	reinit_completion(&priv->status_return_completion);
195 	ret = s10_svc_send_msg(priv, COMMAND_RECONFIG,
196 			       &ctype, sizeof(ctype));
197 	if (ret < 0)
198 		goto init_done;
199 
200 	ret = wait_for_completion_timeout(
201 		&priv->status_return_completion, S10_RECONFIG_TIMEOUT);
202 	if (!ret) {
203 		dev_err(dev, "timeout waiting for RECONFIG_REQUEST\n");
204 		ret = -ETIMEDOUT;
205 		goto init_done;
206 	}
207 
208 	ret = 0;
209 	if (!test_and_clear_bit(SVC_STATUS_OK, &priv->status)) {
210 		ret = -ETIMEDOUT;
211 		goto init_done;
212 	}
213 
214 	/* Allocate buffers from the service layer's pool. */
215 	for (i = 0; i < NUM_SVC_BUFS; i++) {
216 		kbuf = stratix10_svc_allocate_memory(priv->chan, SVC_BUF_SIZE);
217 		if (IS_ERR(kbuf)) {
218 			s10_free_buffers(mgr);
219 			ret = PTR_ERR(kbuf);
220 			goto init_done;
221 		}
222 
223 		priv->svc_bufs[i].buf = kbuf;
224 		priv->svc_bufs[i].lock = 0;
225 	}
226 
227 init_done:
228 	stratix10_svc_done(priv->chan);
229 	return ret;
230 }
231 
232 /*
233  * s10_send_buf - send a buffer to the service layer queue
234  * mgr: fpga manager struct
235  * buf: fpga image buffer
236  * count: size of buf in bytes
237  * Returns # of bytes transferred or -ENOBUFS if the all the buffers are in use
238  * or if the service queue is full. Never returns 0.
239  */
s10_send_buf(struct fpga_manager * mgr,const char * buf,size_t count)240 static int s10_send_buf(struct fpga_manager *mgr, const char *buf, size_t count)
241 {
242 	struct s10_priv *priv = mgr->priv;
243 	struct device *dev = priv->client.dev;
244 	void *svc_buf;
245 	size_t xfer_sz;
246 	int ret;
247 	uint i;
248 
249 	/* get/lock a buffer that that's not being used */
250 	for (i = 0; i < NUM_SVC_BUFS; i++)
251 		if (!test_and_set_bit_lock(SVC_BUF_LOCK,
252 					   &priv->svc_bufs[i].lock))
253 			break;
254 
255 	if (i == NUM_SVC_BUFS)
256 		return -ENOBUFS;
257 
258 	xfer_sz = count < SVC_BUF_SIZE ? count : SVC_BUF_SIZE;
259 
260 	svc_buf = priv->svc_bufs[i].buf;
261 	memcpy(svc_buf, buf, xfer_sz);
262 	ret = s10_svc_send_msg(priv, COMMAND_RECONFIG_DATA_SUBMIT,
263 			       svc_buf, xfer_sz);
264 	if (ret < 0) {
265 		dev_err(dev,
266 			"Error while sending data to service layer (%d)", ret);
267 		clear_bit_unlock(SVC_BUF_LOCK, &priv->svc_bufs[i].lock);
268 		return ret;
269 	}
270 
271 	return xfer_sz;
272 }
273 
274 /*
275  * Send an FPGA image to privileged layers to write to the FPGA.  When done
276  * sending, free all service layer buffers we allocated in write_init.
277  */
s10_ops_write(struct fpga_manager * mgr,const char * buf,size_t count)278 static int s10_ops_write(struct fpga_manager *mgr, const char *buf,
279 			 size_t count)
280 {
281 	struct s10_priv *priv = mgr->priv;
282 	struct device *dev = priv->client.dev;
283 	long wait_status;
284 	int sent = 0;
285 	int ret = 0;
286 
287 	/*
288 	 * Loop waiting for buffers to be returned.  When a buffer is returned,
289 	 * reuse it to send more data or free if if all data has been sent.
290 	 */
291 	while (count > 0 || s10_free_buffer_count(mgr) != NUM_SVC_BUFS) {
292 		reinit_completion(&priv->status_return_completion);
293 
294 		if (count > 0) {
295 			sent = s10_send_buf(mgr, buf, count);
296 			if (sent < 0)
297 				continue;
298 
299 			count -= sent;
300 			buf += sent;
301 		} else {
302 			if (s10_free_buffers(mgr))
303 				return 0;
304 
305 			ret = s10_svc_send_msg(
306 				priv, COMMAND_RECONFIG_DATA_CLAIM,
307 				NULL, 0);
308 			if (ret < 0)
309 				break;
310 		}
311 
312 		/*
313 		 * If callback hasn't already happened, wait for buffers to be
314 		 * returned from service layer
315 		 */
316 		wait_status = 1; /* not timed out */
317 		if (!priv->status)
318 			wait_status = wait_for_completion_timeout(
319 				&priv->status_return_completion,
320 				S10_BUFFER_TIMEOUT);
321 
322 		if (test_and_clear_bit(SVC_STATUS_BUFFER_DONE, &priv->status) ||
323 		    test_and_clear_bit(SVC_STATUS_BUFFER_SUBMITTED,
324 				       &priv->status)) {
325 			ret = 0;
326 			continue;
327 		}
328 
329 		if (test_and_clear_bit(SVC_STATUS_ERROR, &priv->status)) {
330 			dev_err(dev, "ERROR - giving up - SVC_STATUS_ERROR\n");
331 			ret = -EFAULT;
332 			break;
333 		}
334 
335 		if (!wait_status) {
336 			dev_err(dev, "timeout waiting for svc layer buffers\n");
337 			ret = -ETIMEDOUT;
338 			break;
339 		}
340 	}
341 
342 	if (!s10_free_buffers(mgr))
343 		dev_err(dev, "%s not all buffers were freed\n", __func__);
344 
345 	return ret;
346 }
347 
s10_ops_write_complete(struct fpga_manager * mgr,struct fpga_image_info * info)348 static int s10_ops_write_complete(struct fpga_manager *mgr,
349 				  struct fpga_image_info *info)
350 {
351 	struct s10_priv *priv = mgr->priv;
352 	struct device *dev = priv->client.dev;
353 	unsigned long timeout;
354 	int ret;
355 
356 	timeout = usecs_to_jiffies(info->config_complete_timeout_us);
357 
358 	do {
359 		reinit_completion(&priv->status_return_completion);
360 
361 		ret = s10_svc_send_msg(priv, COMMAND_RECONFIG_STATUS, NULL, 0);
362 		if (ret < 0)
363 			break;
364 
365 		ret = wait_for_completion_timeout(
366 			&priv->status_return_completion, timeout);
367 		if (!ret) {
368 			dev_err(dev,
369 				"timeout waiting for RECONFIG_COMPLETED\n");
370 			ret = -ETIMEDOUT;
371 			break;
372 		}
373 		/* Not error or timeout, so ret is # of jiffies until timeout */
374 		timeout = ret;
375 		ret = 0;
376 
377 		if (test_and_clear_bit(SVC_STATUS_COMPLETED, &priv->status))
378 			break;
379 
380 		if (test_and_clear_bit(SVC_STATUS_ERROR, &priv->status)) {
381 			dev_err(dev, "ERROR - giving up - SVC_STATUS_ERROR\n");
382 			ret = -EFAULT;
383 			break;
384 		}
385 	} while (1);
386 
387 	stratix10_svc_done(priv->chan);
388 
389 	return ret;
390 }
391 
392 static const struct fpga_manager_ops s10_ops = {
393 	.write_init = s10_ops_write_init,
394 	.write = s10_ops_write,
395 	.write_complete = s10_ops_write_complete,
396 };
397 
s10_probe(struct platform_device * pdev)398 static int s10_probe(struct platform_device *pdev)
399 {
400 	struct device *dev = &pdev->dev;
401 	struct s10_priv *priv;
402 	struct fpga_manager *mgr;
403 	int ret;
404 
405 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
406 	if (!priv)
407 		return -ENOMEM;
408 
409 	priv->client.dev = dev;
410 	priv->client.receive_cb = s10_receive_callback;
411 	priv->client.priv = priv;
412 
413 	priv->chan = stratix10_svc_request_channel_byname(&priv->client,
414 							  SVC_CLIENT_FPGA);
415 	if (IS_ERR(priv->chan)) {
416 		dev_err(dev, "couldn't get service channel (%s)\n",
417 			SVC_CLIENT_FPGA);
418 		return PTR_ERR(priv->chan);
419 	}
420 
421 	init_completion(&priv->status_return_completion);
422 
423 	mgr = fpga_mgr_register(dev, "Stratix10 SOC FPGA Manager",
424 				&s10_ops, priv);
425 	if (IS_ERR(mgr)) {
426 		dev_err(dev, "unable to register FPGA manager\n");
427 		ret = PTR_ERR(mgr);
428 		goto probe_err;
429 	}
430 
431 	platform_set_drvdata(pdev, mgr);
432 	return 0;
433 
434 probe_err:
435 	stratix10_svc_free_channel(priv->chan);
436 	return ret;
437 }
438 
s10_remove(struct platform_device * pdev)439 static void s10_remove(struct platform_device *pdev)
440 {
441 	struct fpga_manager *mgr = platform_get_drvdata(pdev);
442 	struct s10_priv *priv = mgr->priv;
443 
444 	fpga_mgr_unregister(mgr);
445 	stratix10_svc_free_channel(priv->chan);
446 }
447 
448 static const struct of_device_id s10_of_match[] = {
449 	{.compatible = "intel,stratix10-soc-fpga-mgr"},
450 	{.compatible = "intel,agilex-soc-fpga-mgr"},
451 	{},
452 };
453 
454 MODULE_DEVICE_TABLE(of, s10_of_match);
455 
456 static struct platform_driver s10_driver = {
457 	.probe = s10_probe,
458 	.remove_new = s10_remove,
459 	.driver = {
460 		.name	= "Stratix10 SoC FPGA manager",
461 		.of_match_table = of_match_ptr(s10_of_match),
462 	},
463 };
464 
s10_init(void)465 static int __init s10_init(void)
466 {
467 	struct device_node *fw_np;
468 	struct device_node *np;
469 	int ret;
470 
471 	fw_np = of_find_node_by_name(NULL, "svc");
472 	if (!fw_np)
473 		return -ENODEV;
474 
475 	of_node_get(fw_np);
476 	np = of_find_matching_node(fw_np, s10_of_match);
477 	if (!np) {
478 		of_node_put(fw_np);
479 		return -ENODEV;
480 	}
481 
482 	of_node_put(np);
483 	ret = of_platform_populate(fw_np, s10_of_match, NULL, NULL);
484 	of_node_put(fw_np);
485 	if (ret)
486 		return ret;
487 
488 	return platform_driver_register(&s10_driver);
489 }
490 
s10_exit(void)491 static void __exit s10_exit(void)
492 {
493 	return platform_driver_unregister(&s10_driver);
494 }
495 
496 module_init(s10_init);
497 module_exit(s10_exit);
498 
499 MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
500 MODULE_DESCRIPTION("Intel Stratix 10 SOC FPGA Manager");
501 MODULE_LICENSE("GPL v2");
502