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7#include <linux/interrupt.h>
8#include <linux/list.h>
9#include <linux/io.h>
10#include <linux/of.h>
11#include <linux/irq.h>
12#include <linux/irqdomain.h>
13#include <linux/mailbox_client.h>
14#include <linux/mfd/syscon.h>
15#include <linux/module.h>
16#include <linux/platform_device.h>
17#include <linux/regmap.h>
18#include <linux/soc/qcom/smem.h>
19#include <linux/soc/qcom/smem_state.h>
20#include <linux/spinlock.h>
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38
39#define SMP2P_MAX_ENTRY 16
40#define SMP2P_MAX_ENTRY_NAME 16
41
42#define SMP2P_FEATURE_SSR_ACK 0x1
43
44#define SMP2P_MAGIC 0x504d5324
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60struct smp2p_smem_item {
61 u32 magic;
62 u8 version;
63 unsigned features:24;
64 u16 local_pid;
65 u16 remote_pid;
66 u16 total_entries;
67 u16 valid_entries;
68 u32 flags;
69
70 struct {
71 u8 name[SMP2P_MAX_ENTRY_NAME];
72 u32 value;
73 } entries[SMP2P_MAX_ENTRY];
74} __packed;
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89
90struct smp2p_entry {
91 struct list_head node;
92 struct qcom_smp2p *smp2p;
93
94 const char *name;
95 u32 *value;
96 u32 last_value;
97
98 struct irq_domain *domain;
99 DECLARE_BITMAP(irq_enabled, 32);
100 DECLARE_BITMAP(irq_rising, 32);
101 DECLARE_BITMAP(irq_falling, 32);
102
103 struct qcom_smem_state *state;
104
105 spinlock_t lock;
106};
107
108#define SMP2P_INBOUND 0
109#define SMP2P_OUTBOUND 1
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127
128struct qcom_smp2p {
129 struct device *dev;
130
131 struct smp2p_smem_item *in;
132 struct smp2p_smem_item *out;
133
134 unsigned smem_items[SMP2P_OUTBOUND + 1];
135
136 unsigned valid_entries;
137
138 unsigned local_pid;
139 unsigned remote_pid;
140
141 struct regmap *ipc_regmap;
142 int ipc_offset;
143 int ipc_bit;
144
145 struct mbox_client mbox_client;
146 struct mbox_chan *mbox_chan;
147
148 struct list_head inbound;
149 struct list_head outbound;
150};
151
152static void qcom_smp2p_kick(struct qcom_smp2p *smp2p)
153{
154
155 wmb();
156
157 if (smp2p->mbox_chan) {
158 mbox_send_message(smp2p->mbox_chan, NULL);
159 mbox_client_txdone(smp2p->mbox_chan, 0);
160 } else {
161 regmap_write(smp2p->ipc_regmap, smp2p->ipc_offset, BIT(smp2p->ipc_bit));
162 }
163}
164
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171
172
173static irqreturn_t qcom_smp2p_intr(int irq, void *data)
174{
175 struct smp2p_smem_item *in;
176 struct smp2p_entry *entry;
177 struct qcom_smp2p *smp2p = data;
178 unsigned smem_id = smp2p->smem_items[SMP2P_INBOUND];
179 unsigned pid = smp2p->remote_pid;
180 size_t size;
181 int irq_pin;
182 u32 status;
183 char buf[SMP2P_MAX_ENTRY_NAME];
184 u32 val;
185 int i;
186
187 in = smp2p->in;
188
189
190 if (!in) {
191 in = qcom_smem_get(pid, smem_id, &size);
192 if (IS_ERR(in)) {
193 dev_err(smp2p->dev,
194 "Unable to acquire remote smp2p item\n");
195 return IRQ_HANDLED;
196 }
197
198 smp2p->in = in;
199 }
200
201
202 for (i = smp2p->valid_entries; i < in->valid_entries; i++) {
203 list_for_each_entry(entry, &smp2p->inbound, node) {
204 memcpy(buf, in->entries[i].name, sizeof(buf));
205 if (!strcmp(buf, entry->name)) {
206 entry->value = &in->entries[i].value;
207 break;
208 }
209 }
210 }
211 smp2p->valid_entries = i;
212
213
214 list_for_each_entry(entry, &smp2p->inbound, node) {
215
216 if (!entry->value)
217 continue;
218
219 val = readl(entry->value);
220
221 status = val ^ entry->last_value;
222 entry->last_value = val;
223
224
225 if (!status)
226 continue;
227
228 for_each_set_bit(i, entry->irq_enabled, 32) {
229 if (!(status & BIT(i)))
230 continue;
231
232 if ((val & BIT(i) && test_bit(i, entry->irq_rising)) ||
233 (!(val & BIT(i)) && test_bit(i, entry->irq_falling))) {
234 irq_pin = irq_find_mapping(entry->domain, i);
235 handle_nested_irq(irq_pin);
236 }
237 }
238 }
239
240 return IRQ_HANDLED;
241}
242
243static void smp2p_mask_irq(struct irq_data *irqd)
244{
245 struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
246 irq_hw_number_t irq = irqd_to_hwirq(irqd);
247
248 clear_bit(irq, entry->irq_enabled);
249}
250
251static void smp2p_unmask_irq(struct irq_data *irqd)
252{
253 struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
254 irq_hw_number_t irq = irqd_to_hwirq(irqd);
255
256 set_bit(irq, entry->irq_enabled);
257}
258
259static int smp2p_set_irq_type(struct irq_data *irqd, unsigned int type)
260{
261 struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
262 irq_hw_number_t irq = irqd_to_hwirq(irqd);
263
264 if (!(type & IRQ_TYPE_EDGE_BOTH))
265 return -EINVAL;
266
267 if (type & IRQ_TYPE_EDGE_RISING)
268 set_bit(irq, entry->irq_rising);
269 else
270 clear_bit(irq, entry->irq_rising);
271
272 if (type & IRQ_TYPE_EDGE_FALLING)
273 set_bit(irq, entry->irq_falling);
274 else
275 clear_bit(irq, entry->irq_falling);
276
277 return 0;
278}
279
280static struct irq_chip smp2p_irq_chip = {
281 .name = "smp2p",
282 .irq_mask = smp2p_mask_irq,
283 .irq_unmask = smp2p_unmask_irq,
284 .irq_set_type = smp2p_set_irq_type,
285};
286
287static int smp2p_irq_map(struct irq_domain *d,
288 unsigned int irq,
289 irq_hw_number_t hw)
290{
291 struct smp2p_entry *entry = d->host_data;
292
293 irq_set_chip_and_handler(irq, &smp2p_irq_chip, handle_level_irq);
294 irq_set_chip_data(irq, entry);
295 irq_set_nested_thread(irq, 1);
296 irq_set_noprobe(irq);
297
298 return 0;
299}
300
301static const struct irq_domain_ops smp2p_irq_ops = {
302 .map = smp2p_irq_map,
303 .xlate = irq_domain_xlate_twocell,
304};
305
306static int qcom_smp2p_inbound_entry(struct qcom_smp2p *smp2p,
307 struct smp2p_entry *entry,
308 struct device_node *node)
309{
310 entry->domain = irq_domain_add_linear(node, 32, &smp2p_irq_ops, entry);
311 if (!entry->domain) {
312 dev_err(smp2p->dev, "failed to add irq_domain\n");
313 return -ENOMEM;
314 }
315
316 return 0;
317}
318
319static int smp2p_update_bits(void *data, u32 mask, u32 value)
320{
321 struct smp2p_entry *entry = data;
322 unsigned long flags;
323 u32 orig;
324 u32 val;
325
326 spin_lock_irqsave(&entry->lock, flags);
327 val = orig = readl(entry->value);
328 val &= ~mask;
329 val |= value;
330 writel(val, entry->value);
331 spin_unlock_irqrestore(&entry->lock, flags);
332
333 if (val != orig)
334 qcom_smp2p_kick(entry->smp2p);
335
336 return 0;
337}
338
339static const struct qcom_smem_state_ops smp2p_state_ops = {
340 .update_bits = smp2p_update_bits,
341};
342
343static int qcom_smp2p_outbound_entry(struct qcom_smp2p *smp2p,
344 struct smp2p_entry *entry,
345 struct device_node *node)
346{
347 struct smp2p_smem_item *out = smp2p->out;
348 char buf[SMP2P_MAX_ENTRY_NAME] = {};
349
350
351 strlcpy(buf, entry->name, SMP2P_MAX_ENTRY_NAME);
352 memcpy(out->entries[out->valid_entries].name, buf, SMP2P_MAX_ENTRY_NAME);
353
354
355 entry->value = &out->entries[out->valid_entries].value;
356
357 out->valid_entries++;
358
359 entry->state = qcom_smem_state_register(node, &smp2p_state_ops, entry);
360 if (IS_ERR(entry->state)) {
361 dev_err(smp2p->dev, "failed to register qcom_smem_state\n");
362 return PTR_ERR(entry->state);
363 }
364
365 return 0;
366}
367
368static int qcom_smp2p_alloc_outbound_item(struct qcom_smp2p *smp2p)
369{
370 struct smp2p_smem_item *out;
371 unsigned smem_id = smp2p->smem_items[SMP2P_OUTBOUND];
372 unsigned pid = smp2p->remote_pid;
373 int ret;
374
375 ret = qcom_smem_alloc(pid, smem_id, sizeof(*out));
376 if (ret < 0 && ret != -EEXIST) {
377 if (ret != -EPROBE_DEFER)
378 dev_err(smp2p->dev,
379 "unable to allocate local smp2p item\n");
380 return ret;
381 }
382
383 out = qcom_smem_get(pid, smem_id, NULL);
384 if (IS_ERR(out)) {
385 dev_err(smp2p->dev, "Unable to acquire local smp2p item\n");
386 return PTR_ERR(out);
387 }
388
389 memset(out, 0, sizeof(*out));
390 out->magic = SMP2P_MAGIC;
391 out->local_pid = smp2p->local_pid;
392 out->remote_pid = smp2p->remote_pid;
393 out->total_entries = SMP2P_MAX_ENTRY;
394 out->valid_entries = 0;
395
396
397
398
399
400 wmb();
401 out->version = 1;
402
403 qcom_smp2p_kick(smp2p);
404
405 smp2p->out = out;
406
407 return 0;
408}
409
410static int smp2p_parse_ipc(struct qcom_smp2p *smp2p)
411{
412 struct device_node *syscon;
413 struct device *dev = smp2p->dev;
414 const char *key;
415 int ret;
416
417 syscon = of_parse_phandle(dev->of_node, "qcom,ipc", 0);
418 if (!syscon) {
419 dev_err(dev, "no qcom,ipc node\n");
420 return -ENODEV;
421 }
422
423 smp2p->ipc_regmap = syscon_node_to_regmap(syscon);
424 if (IS_ERR(smp2p->ipc_regmap))
425 return PTR_ERR(smp2p->ipc_regmap);
426
427 key = "qcom,ipc";
428 ret = of_property_read_u32_index(dev->of_node, key, 1, &smp2p->ipc_offset);
429 if (ret < 0) {
430 dev_err(dev, "no offset in %s\n", key);
431 return -EINVAL;
432 }
433
434 ret = of_property_read_u32_index(dev->of_node, key, 2, &smp2p->ipc_bit);
435 if (ret < 0) {
436 dev_err(dev, "no bit in %s\n", key);
437 return -EINVAL;
438 }
439
440 return 0;
441}
442
443static int qcom_smp2p_probe(struct platform_device *pdev)
444{
445 struct smp2p_entry *entry;
446 struct device_node *node;
447 struct qcom_smp2p *smp2p;
448 const char *key;
449 int irq;
450 int ret;
451
452 smp2p = devm_kzalloc(&pdev->dev, sizeof(*smp2p), GFP_KERNEL);
453 if (!smp2p)
454 return -ENOMEM;
455
456 smp2p->dev = &pdev->dev;
457 INIT_LIST_HEAD(&smp2p->inbound);
458 INIT_LIST_HEAD(&smp2p->outbound);
459
460 platform_set_drvdata(pdev, smp2p);
461
462 key = "qcom,smem";
463 ret = of_property_read_u32_array(pdev->dev.of_node, key,
464 smp2p->smem_items, 2);
465 if (ret)
466 return ret;
467
468 key = "qcom,local-pid";
469 ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->local_pid);
470 if (ret)
471 goto report_read_failure;
472
473 key = "qcom,remote-pid";
474 ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->remote_pid);
475 if (ret)
476 goto report_read_failure;
477
478 irq = platform_get_irq(pdev, 0);
479 if (irq < 0)
480 return irq;
481
482 smp2p->mbox_client.dev = &pdev->dev;
483 smp2p->mbox_client.knows_txdone = true;
484 smp2p->mbox_chan = mbox_request_channel(&smp2p->mbox_client, 0);
485 if (IS_ERR(smp2p->mbox_chan)) {
486 if (PTR_ERR(smp2p->mbox_chan) != -ENODEV)
487 return PTR_ERR(smp2p->mbox_chan);
488
489 smp2p->mbox_chan = NULL;
490
491 ret = smp2p_parse_ipc(smp2p);
492 if (ret)
493 return ret;
494 }
495
496 ret = qcom_smp2p_alloc_outbound_item(smp2p);
497 if (ret < 0)
498 goto release_mbox;
499
500 for_each_available_child_of_node(pdev->dev.of_node, node) {
501 entry = devm_kzalloc(&pdev->dev, sizeof(*entry), GFP_KERNEL);
502 if (!entry) {
503 ret = -ENOMEM;
504 goto unwind_interfaces;
505 }
506
507 entry->smp2p = smp2p;
508 spin_lock_init(&entry->lock);
509
510 ret = of_property_read_string(node, "qcom,entry-name", &entry->name);
511 if (ret < 0)
512 goto unwind_interfaces;
513
514 if (of_property_read_bool(node, "interrupt-controller")) {
515 ret = qcom_smp2p_inbound_entry(smp2p, entry, node);
516 if (ret < 0)
517 goto unwind_interfaces;
518
519 list_add(&entry->node, &smp2p->inbound);
520 } else {
521 ret = qcom_smp2p_outbound_entry(smp2p, entry, node);
522 if (ret < 0)
523 goto unwind_interfaces;
524
525 list_add(&entry->node, &smp2p->outbound);
526 }
527 }
528
529
530 qcom_smp2p_kick(smp2p);
531
532 ret = devm_request_threaded_irq(&pdev->dev, irq,
533 NULL, qcom_smp2p_intr,
534 IRQF_ONESHOT,
535 "smp2p", (void *)smp2p);
536 if (ret) {
537 dev_err(&pdev->dev, "failed to request interrupt\n");
538 goto unwind_interfaces;
539 }
540
541
542 return 0;
543
544unwind_interfaces:
545 list_for_each_entry(entry, &smp2p->inbound, node)
546 irq_domain_remove(entry->domain);
547
548 list_for_each_entry(entry, &smp2p->outbound, node)
549 qcom_smem_state_unregister(entry->state);
550
551 smp2p->out->valid_entries = 0;
552
553release_mbox:
554 mbox_free_channel(smp2p->mbox_chan);
555
556 return ret;
557
558report_read_failure:
559 dev_err(&pdev->dev, "failed to read %s\n", key);
560 return -EINVAL;
561}
562
563static int qcom_smp2p_remove(struct platform_device *pdev)
564{
565 struct qcom_smp2p *smp2p = platform_get_drvdata(pdev);
566 struct smp2p_entry *entry;
567
568 list_for_each_entry(entry, &smp2p->inbound, node)
569 irq_domain_remove(entry->domain);
570
571 list_for_each_entry(entry, &smp2p->outbound, node)
572 qcom_smem_state_unregister(entry->state);
573
574 mbox_free_channel(smp2p->mbox_chan);
575
576 smp2p->out->valid_entries = 0;
577
578 return 0;
579}
580
581static const struct of_device_id qcom_smp2p_of_match[] = {
582 { .compatible = "qcom,smp2p" },
583 {}
584};
585MODULE_DEVICE_TABLE(of, qcom_smp2p_of_match);
586
587static struct platform_driver qcom_smp2p_driver = {
588 .probe = qcom_smp2p_probe,
589 .remove = qcom_smp2p_remove,
590 .driver = {
591 .name = "qcom_smp2p",
592 .of_match_table = qcom_smp2p_of_match,
593 },
594};
595module_platform_driver(qcom_smp2p_driver);
596
597MODULE_DESCRIPTION("Qualcomm Shared Memory Point to Point driver");
598MODULE_LICENSE("GPL v2");
599