1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Xilinx Inter Processor Interrupt(IPI) Mailbox Driver
4 *
5 * Copyright (C) 2018 Xilinx, Inc.
6 */
7
8 #include <linux/arm-smccc.h>
9 #include <linux/delay.h>
10 #include <linux/device.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/kernel.h>
14 #include <linux/mailbox_controller.h>
15 #include <linux/mailbox/zynqmp-ipi-message.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/of_address.h>
19 #include <linux/of_device.h>
20 #include <linux/of_irq.h>
21 #include <linux/platform_device.h>
22
23 /* IPI agent ID any */
24 #define IPI_ID_ANY 0xFFUL
25
26 /* indicate if ZynqMP IPI mailbox driver uses SMC calls or HVC calls */
27 #define USE_SMC 0
28 #define USE_HVC 1
29
30 /* Default IPI SMC function IDs */
31 #define SMC_IPI_MAILBOX_OPEN 0x82001000U
32 #define SMC_IPI_MAILBOX_RELEASE 0x82001001U
33 #define SMC_IPI_MAILBOX_STATUS_ENQUIRY 0x82001002U
34 #define SMC_IPI_MAILBOX_NOTIFY 0x82001003U
35 #define SMC_IPI_MAILBOX_ACK 0x82001004U
36 #define SMC_IPI_MAILBOX_ENABLE_IRQ 0x82001005U
37 #define SMC_IPI_MAILBOX_DISABLE_IRQ 0x82001006U
38
39 /* IPI SMC Macros */
40 #define IPI_SMC_ENQUIRY_DIRQ_MASK 0x00000001UL /* Flag to indicate if
41 * notification interrupt
42 * to be disabled.
43 */
44 #define IPI_SMC_ACK_EIRQ_MASK 0x00000001UL /* Flag to indicate if
45 * notification interrupt
46 * to be enabled.
47 */
48
49 /* IPI mailbox status */
50 #define IPI_MB_STATUS_IDLE 0
51 #define IPI_MB_STATUS_SEND_PENDING 1
52 #define IPI_MB_STATUS_RECV_PENDING 2
53
54 #define IPI_MB_CHNL_TX 0 /* IPI mailbox TX channel */
55 #define IPI_MB_CHNL_RX 1 /* IPI mailbox RX channel */
56
57 /**
58 * struct zynqmp_ipi_mchan - Description of a Xilinx ZynqMP IPI mailbox channel
59 * @is_opened: indicate if the IPI channel is opened
60 * @req_buf: local to remote request buffer start address
61 * @resp_buf: local to remote response buffer start address
62 * @req_buf_size: request buffer size
63 * @resp_buf_size: response buffer size
64 * @rx_buf: receive buffer to pass received message to client
65 * @chan_type: channel type
66 */
67 struct zynqmp_ipi_mchan {
68 int is_opened;
69 void __iomem *req_buf;
70 void __iomem *resp_buf;
71 void *rx_buf;
72 size_t req_buf_size;
73 size_t resp_buf_size;
74 unsigned int chan_type;
75 };
76
77 /**
78 * struct zynqmp_ipi_mbox - Description of a ZynqMP IPI mailbox
79 * platform data.
80 * @pdata: pointer to the IPI private data
81 * @dev: device pointer corresponding to the Xilinx ZynqMP
82 * IPI mailbox
83 * @remote_id: remote IPI agent ID
84 * @mbox: mailbox Controller
85 * @mchans: array for channels, tx channel and rx channel.
86 * @irq: IPI agent interrupt ID
87 */
88 struct zynqmp_ipi_mbox {
89 struct zynqmp_ipi_pdata *pdata;
90 struct device dev;
91 u32 remote_id;
92 struct mbox_controller mbox;
93 struct zynqmp_ipi_mchan mchans[2];
94 };
95
96 /**
97 * struct zynqmp_ipi_pdata - Description of z ZynqMP IPI agent platform data.
98 *
99 * @dev: device pointer corresponding to the Xilinx ZynqMP
100 * IPI agent
101 * @irq: IPI agent interrupt ID
102 * @method: IPI SMC or HVC is going to be used
103 * @local_id: local IPI agent ID
104 * @num_mboxes: number of mailboxes of this IPI agent
105 * @ipi_mboxes: IPI mailboxes of this IPI agent
106 */
107 struct zynqmp_ipi_pdata {
108 struct device *dev;
109 int irq;
110 unsigned int method;
111 u32 local_id;
112 int num_mboxes;
113 struct zynqmp_ipi_mbox *ipi_mboxes;
114 };
115
116 static struct device_driver zynqmp_ipi_mbox_driver = {
117 .owner = THIS_MODULE,
118 .name = "zynqmp-ipi-mbox",
119 };
120
zynqmp_ipi_fw_call(struct zynqmp_ipi_mbox * ipi_mbox,unsigned long a0,unsigned long a3,struct arm_smccc_res * res)121 static void zynqmp_ipi_fw_call(struct zynqmp_ipi_mbox *ipi_mbox,
122 unsigned long a0, unsigned long a3,
123 struct arm_smccc_res *res)
124 {
125 struct zynqmp_ipi_pdata *pdata = ipi_mbox->pdata;
126 unsigned long a1, a2;
127
128 a1 = pdata->local_id;
129 a2 = ipi_mbox->remote_id;
130 if (pdata->method == USE_SMC)
131 arm_smccc_smc(a0, a1, a2, a3, 0, 0, 0, 0, res);
132 else
133 arm_smccc_hvc(a0, a1, a2, a3, 0, 0, 0, 0, res);
134 }
135
136 /**
137 * zynqmp_ipi_interrupt - Interrupt handler for IPI notification
138 *
139 * @irq: Interrupt number
140 * @data: ZynqMP IPI mailbox platform data.
141 *
142 * Return: -EINVAL if there is no instance
143 * IRQ_NONE if the interrupt is not ours.
144 * IRQ_HANDLED if the rx interrupt was successfully handled.
145 */
zynqmp_ipi_interrupt(int irq,void * data)146 static irqreturn_t zynqmp_ipi_interrupt(int irq, void *data)
147 {
148 struct zynqmp_ipi_pdata *pdata = data;
149 struct mbox_chan *chan;
150 struct zynqmp_ipi_mbox *ipi_mbox;
151 struct zynqmp_ipi_mchan *mchan;
152 struct zynqmp_ipi_message *msg;
153 u64 arg0, arg3;
154 struct arm_smccc_res res;
155 int ret, i;
156
157 (void)irq;
158 arg0 = SMC_IPI_MAILBOX_STATUS_ENQUIRY;
159 arg3 = IPI_SMC_ENQUIRY_DIRQ_MASK;
160 for (i = 0; i < pdata->num_mboxes; i++) {
161 ipi_mbox = &pdata->ipi_mboxes[i];
162 mchan = &ipi_mbox->mchans[IPI_MB_CHNL_RX];
163 chan = &ipi_mbox->mbox.chans[IPI_MB_CHNL_RX];
164 zynqmp_ipi_fw_call(ipi_mbox, arg0, arg3, &res);
165 ret = (int)(res.a0 & 0xFFFFFFFF);
166 if (ret > 0 && ret & IPI_MB_STATUS_RECV_PENDING) {
167 if (mchan->is_opened) {
168 msg = mchan->rx_buf;
169 msg->len = mchan->req_buf_size;
170 memcpy_fromio(msg->data, mchan->req_buf,
171 msg->len);
172 mbox_chan_received_data(chan, (void *)msg);
173 return IRQ_HANDLED;
174 }
175 }
176 }
177 return IRQ_NONE;
178 }
179
180 /**
181 * zynqmp_ipi_peek_data - Peek to see if there are any rx messages.
182 *
183 * @chan: Channel Pointer
184 *
185 * Return: 'true' if there is pending rx data, 'false' if there is none.
186 */
zynqmp_ipi_peek_data(struct mbox_chan * chan)187 static bool zynqmp_ipi_peek_data(struct mbox_chan *chan)
188 {
189 struct device *dev = chan->mbox->dev;
190 struct zynqmp_ipi_mbox *ipi_mbox = dev_get_drvdata(dev);
191 struct zynqmp_ipi_mchan *mchan = chan->con_priv;
192 int ret;
193 u64 arg0;
194 struct arm_smccc_res res;
195
196 if (WARN_ON(!ipi_mbox)) {
197 dev_err(dev, "no platform drv data??\n");
198 return false;
199 }
200
201 arg0 = SMC_IPI_MAILBOX_STATUS_ENQUIRY;
202 zynqmp_ipi_fw_call(ipi_mbox, arg0, 0, &res);
203 ret = (int)(res.a0 & 0xFFFFFFFF);
204
205 if (mchan->chan_type == IPI_MB_CHNL_TX) {
206 /* TX channel, check if the message has been acked
207 * by the remote, if yes, response is available.
208 */
209 if (ret < 0 || ret & IPI_MB_STATUS_SEND_PENDING)
210 return false;
211 else
212 return true;
213 } else if (ret > 0 && ret & IPI_MB_STATUS_RECV_PENDING) {
214 /* RX channel, check if there is message arrived. */
215 return true;
216 }
217 return false;
218 }
219
220 /**
221 * zynqmp_ipi_last_tx_done - See if the last tx message is sent
222 *
223 * @chan: Channel pointer
224 *
225 * Return: 'true' is no pending tx data, 'false' if there are any.
226 */
zynqmp_ipi_last_tx_done(struct mbox_chan * chan)227 static bool zynqmp_ipi_last_tx_done(struct mbox_chan *chan)
228 {
229 struct device *dev = chan->mbox->dev;
230 struct zynqmp_ipi_mbox *ipi_mbox = dev_get_drvdata(dev);
231 struct zynqmp_ipi_mchan *mchan = chan->con_priv;
232 int ret;
233 u64 arg0;
234 struct arm_smccc_res res;
235
236 if (WARN_ON(!ipi_mbox)) {
237 dev_err(dev, "no platform drv data??\n");
238 return false;
239 }
240
241 if (mchan->chan_type == IPI_MB_CHNL_TX) {
242 /* We only need to check if the message been taken
243 * by the remote in the TX channel
244 */
245 arg0 = SMC_IPI_MAILBOX_STATUS_ENQUIRY;
246 zynqmp_ipi_fw_call(ipi_mbox, arg0, 0, &res);
247 /* Check the SMC call status, a0 of the result */
248 ret = (int)(res.a0 & 0xFFFFFFFF);
249 if (ret < 0 || ret & IPI_MB_STATUS_SEND_PENDING)
250 return false;
251 return true;
252 }
253 /* Always true for the response message in RX channel */
254 return true;
255 }
256
257 /**
258 * zynqmp_ipi_send_data - Send data
259 *
260 * @chan: Channel Pointer
261 * @data: Message Pointer
262 *
263 * Return: 0 if all goes good, else appropriate error messages.
264 */
zynqmp_ipi_send_data(struct mbox_chan * chan,void * data)265 static int zynqmp_ipi_send_data(struct mbox_chan *chan, void *data)
266 {
267 struct device *dev = chan->mbox->dev;
268 struct zynqmp_ipi_mbox *ipi_mbox = dev_get_drvdata(dev);
269 struct zynqmp_ipi_mchan *mchan = chan->con_priv;
270 struct zynqmp_ipi_message *msg = data;
271 u64 arg0;
272 struct arm_smccc_res res;
273
274 if (WARN_ON(!ipi_mbox)) {
275 dev_err(dev, "no platform drv data??\n");
276 return -EINVAL;
277 }
278
279 if (mchan->chan_type == IPI_MB_CHNL_TX) {
280 /* Send request message */
281 if (msg && msg->len > mchan->req_buf_size) {
282 dev_err(dev, "channel %d message length %u > max %lu\n",
283 mchan->chan_type, (unsigned int)msg->len,
284 mchan->req_buf_size);
285 return -EINVAL;
286 }
287 if (msg && msg->len)
288 memcpy_toio(mchan->req_buf, msg->data, msg->len);
289 /* Kick IPI mailbox to send message */
290 arg0 = SMC_IPI_MAILBOX_NOTIFY;
291 zynqmp_ipi_fw_call(ipi_mbox, arg0, 0, &res);
292 } else {
293 /* Send response message */
294 if (msg && msg->len > mchan->resp_buf_size) {
295 dev_err(dev, "channel %d message length %u > max %lu\n",
296 mchan->chan_type, (unsigned int)msg->len,
297 mchan->resp_buf_size);
298 return -EINVAL;
299 }
300 if (msg && msg->len)
301 memcpy_toio(mchan->resp_buf, msg->data, msg->len);
302 arg0 = SMC_IPI_MAILBOX_ACK;
303 zynqmp_ipi_fw_call(ipi_mbox, arg0, IPI_SMC_ACK_EIRQ_MASK,
304 &res);
305 }
306 return 0;
307 }
308
309 /**
310 * zynqmp_ipi_startup - Startup the IPI channel
311 *
312 * @chan: Channel pointer
313 *
314 * Return: 0 if all goes good, else return corresponding error message
315 */
zynqmp_ipi_startup(struct mbox_chan * chan)316 static int zynqmp_ipi_startup(struct mbox_chan *chan)
317 {
318 struct device *dev = chan->mbox->dev;
319 struct zynqmp_ipi_mbox *ipi_mbox = dev_get_drvdata(dev);
320 struct zynqmp_ipi_mchan *mchan = chan->con_priv;
321 u64 arg0;
322 struct arm_smccc_res res;
323 int ret = 0;
324 unsigned int nchan_type;
325
326 if (mchan->is_opened)
327 return 0;
328
329 /* If no channel has been opened, open the IPI mailbox */
330 nchan_type = (mchan->chan_type + 1) % 2;
331 if (!ipi_mbox->mchans[nchan_type].is_opened) {
332 arg0 = SMC_IPI_MAILBOX_OPEN;
333 zynqmp_ipi_fw_call(ipi_mbox, arg0, 0, &res);
334 /* Check the SMC call status, a0 of the result */
335 ret = (int)(res.a0 & 0xFFFFFFFF);
336 if (ret < 0) {
337 dev_err(dev, "SMC to open the IPI channel failed.\n");
338 return ret;
339 }
340 ret = 0;
341 }
342
343 /* If it is RX channel, enable the IPI notification interrupt */
344 if (mchan->chan_type == IPI_MB_CHNL_RX) {
345 arg0 = SMC_IPI_MAILBOX_ENABLE_IRQ;
346 zynqmp_ipi_fw_call(ipi_mbox, arg0, 0, &res);
347 }
348 mchan->is_opened = 1;
349
350 return ret;
351 }
352
353 /**
354 * zynqmp_ipi_shutdown - Shutdown the IPI channel
355 *
356 * @chan: Channel pointer
357 */
zynqmp_ipi_shutdown(struct mbox_chan * chan)358 static void zynqmp_ipi_shutdown(struct mbox_chan *chan)
359 {
360 struct device *dev = chan->mbox->dev;
361 struct zynqmp_ipi_mbox *ipi_mbox = dev_get_drvdata(dev);
362 struct zynqmp_ipi_mchan *mchan = chan->con_priv;
363 u64 arg0;
364 struct arm_smccc_res res;
365 unsigned int chan_type;
366
367 if (!mchan->is_opened)
368 return;
369
370 /* If it is RX channel, disable notification interrupt */
371 chan_type = mchan->chan_type;
372 if (chan_type == IPI_MB_CHNL_RX) {
373 arg0 = SMC_IPI_MAILBOX_DISABLE_IRQ;
374 zynqmp_ipi_fw_call(ipi_mbox, arg0, 0, &res);
375 }
376 /* Release IPI mailbox if no other channel is opened */
377 chan_type = (chan_type + 1) % 2;
378 if (!ipi_mbox->mchans[chan_type].is_opened) {
379 arg0 = SMC_IPI_MAILBOX_RELEASE;
380 zynqmp_ipi_fw_call(ipi_mbox, arg0, 0, &res);
381 }
382
383 mchan->is_opened = 0;
384 }
385
386 /* ZynqMP IPI mailbox operations */
387 static const struct mbox_chan_ops zynqmp_ipi_chan_ops = {
388 .startup = zynqmp_ipi_startup,
389 .shutdown = zynqmp_ipi_shutdown,
390 .peek_data = zynqmp_ipi_peek_data,
391 .last_tx_done = zynqmp_ipi_last_tx_done,
392 .send_data = zynqmp_ipi_send_data,
393 };
394
395 /**
396 * zynqmp_ipi_of_xlate - Translate of phandle to IPI mailbox channel
397 *
398 * @mbox: mailbox controller pointer
399 * @p: phandle pointer
400 *
401 * Return: Mailbox channel, else return error pointer.
402 */
zynqmp_ipi_of_xlate(struct mbox_controller * mbox,const struct of_phandle_args * p)403 static struct mbox_chan *zynqmp_ipi_of_xlate(struct mbox_controller *mbox,
404 const struct of_phandle_args *p)
405 {
406 struct mbox_chan *chan;
407 struct device *dev = mbox->dev;
408 unsigned int chan_type;
409
410 /* Only supports TX and RX channels */
411 chan_type = p->args[0];
412 if (chan_type != IPI_MB_CHNL_TX && chan_type != IPI_MB_CHNL_RX) {
413 dev_err(dev, "req chnl failure: invalid chnl type %u.\n",
414 chan_type);
415 return ERR_PTR(-EINVAL);
416 }
417 chan = &mbox->chans[chan_type];
418 return chan;
419 }
420
421 static const struct of_device_id zynqmp_ipi_of_match[] = {
422 { .compatible = "xlnx,zynqmp-ipi-mailbox" },
423 {},
424 };
425 MODULE_DEVICE_TABLE(of, zynqmp_ipi_of_match);
426
427 /**
428 * zynqmp_ipi_mbox_get_buf_res - Get buffer resource from the IPI dev node
429 *
430 * @node: IPI mbox device child node
431 * @name: name of the IPI buffer
432 * @res: pointer to where the resource information will be stored.
433 *
434 * Return: 0 for success, negative value for failure
435 */
zynqmp_ipi_mbox_get_buf_res(struct device_node * node,const char * name,struct resource * res)436 static int zynqmp_ipi_mbox_get_buf_res(struct device_node *node,
437 const char *name,
438 struct resource *res)
439 {
440 int ret, index;
441
442 index = of_property_match_string(node, "reg-names", name);
443 if (index >= 0) {
444 ret = of_address_to_resource(node, index, res);
445 if (ret < 0)
446 return -EINVAL;
447 return 0;
448 }
449 return -ENODEV;
450 }
451
452 /**
453 * zynqmp_ipi_mbox_dev_release() - release the existence of a ipi mbox dev
454 *
455 * @dev: the ipi mailbox device
456 *
457 * This is to avoid the no device release() function kernel warning.
458 *
459 */
zynqmp_ipi_mbox_dev_release(struct device * dev)460 static void zynqmp_ipi_mbox_dev_release(struct device *dev)
461 {
462 (void)dev;
463 }
464
465 /**
466 * zynqmp_ipi_mbox_probe - probe IPI mailbox resource from device node
467 *
468 * @ipi_mbox: pointer to IPI mailbox private data structure
469 * @node: IPI mailbox device node
470 *
471 * Return: 0 for success, negative value for failure
472 */
zynqmp_ipi_mbox_probe(struct zynqmp_ipi_mbox * ipi_mbox,struct device_node * node)473 static int zynqmp_ipi_mbox_probe(struct zynqmp_ipi_mbox *ipi_mbox,
474 struct device_node *node)
475 {
476 struct zynqmp_ipi_mchan *mchan;
477 struct mbox_chan *chans;
478 struct mbox_controller *mbox;
479 struct resource res;
480 struct device *dev, *mdev;
481 const char *name;
482 int ret;
483
484 dev = ipi_mbox->pdata->dev;
485 /* Initialize dev for IPI mailbox */
486 ipi_mbox->dev.parent = dev;
487 ipi_mbox->dev.release = NULL;
488 ipi_mbox->dev.of_node = node;
489 dev_set_name(&ipi_mbox->dev, "%s", of_node_full_name(node));
490 dev_set_drvdata(&ipi_mbox->dev, ipi_mbox);
491 ipi_mbox->dev.release = zynqmp_ipi_mbox_dev_release;
492 ipi_mbox->dev.driver = &zynqmp_ipi_mbox_driver;
493 ret = device_register(&ipi_mbox->dev);
494 if (ret) {
495 dev_err(dev, "Failed to register ipi mbox dev.\n");
496 return ret;
497 }
498 mdev = &ipi_mbox->dev;
499
500 mchan = &ipi_mbox->mchans[IPI_MB_CHNL_TX];
501 name = "local_request_region";
502 ret = zynqmp_ipi_mbox_get_buf_res(node, name, &res);
503 if (!ret) {
504 mchan->req_buf_size = resource_size(&res);
505 mchan->req_buf = devm_ioremap(mdev, res.start,
506 mchan->req_buf_size);
507 if (IS_ERR(mchan->req_buf)) {
508 dev_err(mdev, "Unable to map IPI buffer I/O memory\n");
509 ret = PTR_ERR(mchan->req_buf);
510 return ret;
511 }
512 } else if (ret != -ENODEV) {
513 dev_err(mdev, "Unmatched resource %s, %d.\n", name, ret);
514 return ret;
515 }
516
517 name = "remote_response_region";
518 ret = zynqmp_ipi_mbox_get_buf_res(node, name, &res);
519 if (!ret) {
520 mchan->resp_buf_size = resource_size(&res);
521 mchan->resp_buf = devm_ioremap(mdev, res.start,
522 mchan->resp_buf_size);
523 if (IS_ERR(mchan->resp_buf)) {
524 dev_err(mdev, "Unable to map IPI buffer I/O memory\n");
525 ret = PTR_ERR(mchan->resp_buf);
526 return ret;
527 }
528 } else if (ret != -ENODEV) {
529 dev_err(mdev, "Unmatched resource %s.\n", name);
530 return ret;
531 }
532 mchan->rx_buf = devm_kzalloc(mdev,
533 mchan->resp_buf_size +
534 sizeof(struct zynqmp_ipi_message),
535 GFP_KERNEL);
536 if (!mchan->rx_buf)
537 return -ENOMEM;
538
539 mchan = &ipi_mbox->mchans[IPI_MB_CHNL_RX];
540 name = "remote_request_region";
541 ret = zynqmp_ipi_mbox_get_buf_res(node, name, &res);
542 if (!ret) {
543 mchan->req_buf_size = resource_size(&res);
544 mchan->req_buf = devm_ioremap(mdev, res.start,
545 mchan->req_buf_size);
546 if (IS_ERR(mchan->req_buf)) {
547 dev_err(mdev, "Unable to map IPI buffer I/O memory\n");
548 ret = PTR_ERR(mchan->req_buf);
549 return ret;
550 }
551 } else if (ret != -ENODEV) {
552 dev_err(mdev, "Unmatched resource %s.\n", name);
553 return ret;
554 }
555
556 name = "local_response_region";
557 ret = zynqmp_ipi_mbox_get_buf_res(node, name, &res);
558 if (!ret) {
559 mchan->resp_buf_size = resource_size(&res);
560 mchan->resp_buf = devm_ioremap(mdev, res.start,
561 mchan->resp_buf_size);
562 if (IS_ERR(mchan->resp_buf)) {
563 dev_err(mdev, "Unable to map IPI buffer I/O memory\n");
564 ret = PTR_ERR(mchan->resp_buf);
565 return ret;
566 }
567 } else if (ret != -ENODEV) {
568 dev_err(mdev, "Unmatched resource %s.\n", name);
569 return ret;
570 }
571 mchan->rx_buf = devm_kzalloc(mdev,
572 mchan->resp_buf_size +
573 sizeof(struct zynqmp_ipi_message),
574 GFP_KERNEL);
575 if (!mchan->rx_buf)
576 return -ENOMEM;
577
578 /* Get the IPI remote agent ID */
579 ret = of_property_read_u32(node, "xlnx,ipi-id", &ipi_mbox->remote_id);
580 if (ret < 0) {
581 dev_err(dev, "No IPI remote ID is specified.\n");
582 return ret;
583 }
584
585 mbox = &ipi_mbox->mbox;
586 mbox->dev = mdev;
587 mbox->ops = &zynqmp_ipi_chan_ops;
588 mbox->num_chans = 2;
589 mbox->txdone_irq = false;
590 mbox->txdone_poll = true;
591 mbox->txpoll_period = 5;
592 mbox->of_xlate = zynqmp_ipi_of_xlate;
593 chans = devm_kzalloc(mdev, 2 * sizeof(*chans), GFP_KERNEL);
594 if (!chans)
595 return -ENOMEM;
596 mbox->chans = chans;
597 chans[IPI_MB_CHNL_TX].con_priv = &ipi_mbox->mchans[IPI_MB_CHNL_TX];
598 chans[IPI_MB_CHNL_RX].con_priv = &ipi_mbox->mchans[IPI_MB_CHNL_RX];
599 ipi_mbox->mchans[IPI_MB_CHNL_TX].chan_type = IPI_MB_CHNL_TX;
600 ipi_mbox->mchans[IPI_MB_CHNL_RX].chan_type = IPI_MB_CHNL_RX;
601 ret = devm_mbox_controller_register(mdev, mbox);
602 if (ret)
603 dev_err(mdev,
604 "Failed to register mbox_controller(%d)\n", ret);
605 else
606 dev_info(mdev,
607 "Registered ZynqMP IPI mbox with TX/RX channels.\n");
608 return ret;
609 }
610
611 /**
612 * zynqmp_ipi_free_mboxes - Free IPI mailboxes devices
613 *
614 * @pdata: IPI private data
615 */
zynqmp_ipi_free_mboxes(struct zynqmp_ipi_pdata * pdata)616 static void zynqmp_ipi_free_mboxes(struct zynqmp_ipi_pdata *pdata)
617 {
618 struct zynqmp_ipi_mbox *ipi_mbox;
619 int i;
620
621 i = pdata->num_mboxes;
622 for (; i >= 0; i--) {
623 ipi_mbox = &pdata->ipi_mboxes[i];
624 if (ipi_mbox->dev.parent) {
625 mbox_controller_unregister(&ipi_mbox->mbox);
626 device_unregister(&ipi_mbox->dev);
627 }
628 }
629 }
630
zynqmp_ipi_probe(struct platform_device * pdev)631 static int zynqmp_ipi_probe(struct platform_device *pdev)
632 {
633 struct device *dev = &pdev->dev;
634 struct device_node *nc, *np = pdev->dev.of_node;
635 struct zynqmp_ipi_pdata *pdata;
636 struct zynqmp_ipi_mbox *mbox;
637 int num_mboxes, ret = -EINVAL;
638
639 num_mboxes = of_get_child_count(np);
640 pdata = devm_kzalloc(dev, sizeof(*pdata) + (num_mboxes * sizeof(*mbox)),
641 GFP_KERNEL);
642 if (!pdata)
643 return -ENOMEM;
644 pdata->dev = dev;
645
646 /* Get the IPI local agents ID */
647 ret = of_property_read_u32(np, "xlnx,ipi-id", &pdata->local_id);
648 if (ret < 0) {
649 dev_err(dev, "No IPI local ID is specified.\n");
650 return ret;
651 }
652
653 pdata->num_mboxes = num_mboxes;
654 pdata->ipi_mboxes = (struct zynqmp_ipi_mbox *)
655 ((char *)pdata + sizeof(*pdata));
656
657 mbox = pdata->ipi_mboxes;
658 for_each_available_child_of_node(np, nc) {
659 mbox->pdata = pdata;
660 ret = zynqmp_ipi_mbox_probe(mbox, nc);
661 if (ret) {
662 dev_err(dev, "failed to probe subdev.\n");
663 ret = -EINVAL;
664 goto free_mbox_dev;
665 }
666 mbox++;
667 }
668
669 /* IPI IRQ */
670 ret = platform_get_irq(pdev, 0);
671 if (ret < 0) {
672 dev_err(dev, "unable to find IPI IRQ.\n");
673 goto free_mbox_dev;
674 }
675 pdata->irq = ret;
676 ret = devm_request_irq(dev, pdata->irq, zynqmp_ipi_interrupt,
677 IRQF_SHARED, dev_name(dev), pdata);
678 if (ret) {
679 dev_err(dev, "IRQ %d is not requested successfully.\n",
680 pdata->irq);
681 goto free_mbox_dev;
682 }
683
684 platform_set_drvdata(pdev, pdata);
685 return ret;
686
687 free_mbox_dev:
688 zynqmp_ipi_free_mboxes(pdata);
689 return ret;
690 }
691
zynqmp_ipi_remove(struct platform_device * pdev)692 static int zynqmp_ipi_remove(struct platform_device *pdev)
693 {
694 struct zynqmp_ipi_pdata *pdata;
695
696 pdata = platform_get_drvdata(pdev);
697 zynqmp_ipi_free_mboxes(pdata);
698
699 return 0;
700 }
701
702 static struct platform_driver zynqmp_ipi_driver = {
703 .probe = zynqmp_ipi_probe,
704 .remove = zynqmp_ipi_remove,
705 .driver = {
706 .name = "zynqmp-ipi",
707 .of_match_table = of_match_ptr(zynqmp_ipi_of_match),
708 },
709 };
710
zynqmp_ipi_init(void)711 static int __init zynqmp_ipi_init(void)
712 {
713 return platform_driver_register(&zynqmp_ipi_driver);
714 }
715 subsys_initcall(zynqmp_ipi_init);
716
zynqmp_ipi_exit(void)717 static void __exit zynqmp_ipi_exit(void)
718 {
719 platform_driver_unregister(&zynqmp_ipi_driver);
720 }
721 module_exit(zynqmp_ipi_exit);
722
723 MODULE_LICENSE("GPL v2");
724 MODULE_DESCRIPTION("Xilinx ZynqMP IPI Mailbox driver");
725 MODULE_AUTHOR("Xilinx Inc.");
726