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 */
33struct s10_svc_buf {
34 char *buf;
35 unsigned long lock;
36};
37
38struct 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
46static 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: &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 */
72static 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 addr: &priv->svc_bufs[i].lock)) {
86 stratix10_svc_free_memory(chan: priv->chan,
87 kaddr: 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 */
99static 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 */
120static 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 addr: &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 */
143static 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(nr: i, addr: &priv->status);
161
162 if (status & BIT(SVC_STATUS_BUFFER_DONE)) {
163 s10_unlock_bufs(priv, kaddr: data->kaddr1);
164 s10_unlock_bufs(priv, kaddr: data->kaddr2);
165 s10_unlock_bufs(priv, kaddr: 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 */
175static 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(x: &priv->status_return_completion);
195 ret = s10_svc_send_msg(priv, command: COMMAND_RECONFIG,
196 payload: &ctype, payload_length: sizeof(ctype));
197 if (ret < 0)
198 goto init_done;
199
200 ret = wait_for_completion_timeout(
201 x: &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, addr: &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(chan: priv->chan, SVC_BUF_SIZE);
217 if (IS_ERR(ptr: kbuf)) {
218 s10_free_buffers(mgr);
219 ret = PTR_ERR(ptr: kbuf);
220 goto init_done;
221 }
222
223 priv->svc_bufs[i].buf = kbuf;
224 priv->svc_bufs[i].lock = 0;
225 }
226
227init_done:
228 stratix10_svc_done(chan: 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 */
240static 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 addr: &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: COMMAND_RECONFIG_DATA_SUBMIT,
263 payload: svc_buf, payload_length: 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, addr: &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 */
278static 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(x: &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: COMMAND_RECONFIG_DATA_CLAIM,
307 NULL, payload_length: 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 x: &priv->status_return_completion,
320 S10_BUFFER_TIMEOUT);
321
322 if (test_and_clear_bit(SVC_STATUS_BUFFER_DONE, addr: &priv->status) ||
323 test_and_clear_bit(SVC_STATUS_BUFFER_SUBMITTED,
324 addr: &priv->status)) {
325 ret = 0;
326 continue;
327 }
328
329 if (test_and_clear_bit(SVC_STATUS_ERROR, addr: &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
348static 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(u: info->config_complete_timeout_us);
357
358 do {
359 reinit_completion(x: &priv->status_return_completion);
360
361 ret = s10_svc_send_msg(priv, command: COMMAND_RECONFIG_STATUS, NULL, payload_length: 0);
362 if (ret < 0)
363 break;
364
365 ret = wait_for_completion_timeout(
366 x: &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, addr: &priv->status))
378 break;
379
380 if (test_and_clear_bit(SVC_STATUS_ERROR, addr: &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(chan: priv->chan);
388
389 return ret;
390}
391
392static 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
398static 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, size: 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(client: &priv->client,
414 SVC_CLIENT_FPGA);
415 if (IS_ERR(ptr: priv->chan)) {
416 dev_err(dev, "couldn't get service channel (%s)\n",
417 SVC_CLIENT_FPGA);
418 return PTR_ERR(ptr: priv->chan);
419 }
420
421 init_completion(x: &priv->status_return_completion);
422
423 mgr = fpga_mgr_register(parent: dev, name: "Stratix10 SOC FPGA Manager",
424 mops: &s10_ops, priv);
425 if (IS_ERR(ptr: mgr)) {
426 dev_err(dev, "unable to register FPGA manager\n");
427 ret = PTR_ERR(ptr: mgr);
428 goto probe_err;
429 }
430
431 platform_set_drvdata(pdev, data: mgr);
432 return 0;
433
434probe_err:
435 stratix10_svc_free_channel(chan: priv->chan);
436 return ret;
437}
438
439static int 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(chan: priv->chan);
446
447 return 0;
448}
449
450static const struct of_device_id s10_of_match[] = {
451 {.compatible = "intel,stratix10-soc-fpga-mgr"},
452 {.compatible = "intel,agilex-soc-fpga-mgr"},
453 {},
454};
455
456MODULE_DEVICE_TABLE(of, s10_of_match);
457
458static struct platform_driver s10_driver = {
459 .probe = s10_probe,
460 .remove = s10_remove,
461 .driver = {
462 .name = "Stratix10 SoC FPGA manager",
463 .of_match_table = of_match_ptr(s10_of_match),
464 },
465};
466
467static int __init s10_init(void)
468{
469 struct device_node *fw_np;
470 struct device_node *np;
471 int ret;
472
473 fw_np = of_find_node_by_name(NULL, name: "svc");
474 if (!fw_np)
475 return -ENODEV;
476
477 of_node_get(node: fw_np);
478 np = of_find_matching_node(from: fw_np, matches: s10_of_match);
479 if (!np) {
480 of_node_put(node: fw_np);
481 return -ENODEV;
482 }
483
484 of_node_put(node: np);
485 ret = of_platform_populate(root: fw_np, matches: s10_of_match, NULL, NULL);
486 of_node_put(node: fw_np);
487 if (ret)
488 return ret;
489
490 return platform_driver_register(&s10_driver);
491}
492
493static void __exit s10_exit(void)
494{
495 return platform_driver_unregister(&s10_driver);
496}
497
498module_init(s10_init);
499module_exit(s10_exit);
500
501MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
502MODULE_DESCRIPTION("Intel Stratix 10 SOC FPGA Manager");
503MODULE_LICENSE("GPL v2");
504

source code of linux/drivers/fpga/stratix10-soc.c