1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * APM X-Gene SoC Hardware Monitoring Driver
4 *
5 * Copyright (c) 2016, Applied Micro Circuits Corporation
6 * Author: Loc Ho <lho@apm.com>
7 * Hoan Tran <hotran@apm.com>
8 *
9 * This driver provides the following features:
10 * - Retrieve CPU total power (uW)
11 * - Retrieve IO total power (uW)
12 * - Retrieve SoC temperature (milli-degree C) and alarm
13 */
14#include <linux/acpi.h>
15#include <linux/dma-mapping.h>
16#include <linux/hwmon.h>
17#include <linux/hwmon-sysfs.h>
18#include <linux/io.h>
19#include <linux/interrupt.h>
20#include <linux/kfifo.h>
21#include <linux/mailbox_controller.h>
22#include <linux/mailbox_client.h>
23#include <linux/module.h>
24#include <linux/of.h>
25#include <linux/platform_device.h>
26
27#include <acpi/pcc.h>
28
29/* SLIMpro message defines */
30#define MSG_TYPE_DBG 0
31#define MSG_TYPE_ERR 7
32#define MSG_TYPE_PWRMGMT 9
33
34#define MSG_TYPE(v) (((v) & 0xF0000000) >> 28)
35#define MSG_TYPE_SET(v) (((v) << 28) & 0xF0000000)
36#define MSG_SUBTYPE(v) (((v) & 0x0F000000) >> 24)
37#define MSG_SUBTYPE_SET(v) (((v) << 24) & 0x0F000000)
38
39#define DBG_SUBTYPE_SENSOR_READ 4
40#define SENSOR_RD_MSG 0x04FFE902
41#define SENSOR_RD_EN_ADDR(a) ((a) & 0x000FFFFF)
42#define PMD_PWR_REG 0x20
43#define PMD_PWR_MW_REG 0x26
44#define SOC_PWR_REG 0x21
45#define SOC_PWR_MW_REG 0x27
46#define SOC_TEMP_REG 0x10
47
48#define TEMP_NEGATIVE_BIT 8
49#define SENSOR_INVALID_DATA BIT(15)
50
51#define PWRMGMT_SUBTYPE_TPC 1
52#define TPC_ALARM 2
53#define TPC_GET_ALARM 3
54#define TPC_CMD(v) (((v) & 0x00FF0000) >> 16)
55#define TPC_CMD_SET(v) (((v) << 16) & 0x00FF0000)
56#define TPC_EN_MSG(hndl, cmd, type) \
57 (MSG_TYPE_SET(MSG_TYPE_PWRMGMT) | \
58 MSG_SUBTYPE_SET(hndl) | TPC_CMD_SET(cmd) | type)
59
60/*
61 * Arbitrary retries in case the remote processor is slow to respond
62 * to PCC commands
63 */
64#define PCC_NUM_RETRIES 500
65
66#define ASYNC_MSG_FIFO_SIZE 16
67#define MBOX_OP_TIMEOUTMS 1000
68
69#define WATT_TO_mWATT(x) ((x) * 1000)
70#define mWATT_TO_uWATT(x) ((x) * 1000)
71#define CELSIUS_TO_mCELSIUS(x) ((x) * 1000)
72
73#define to_xgene_hwmon_dev(cl) \
74 container_of(cl, struct xgene_hwmon_dev, mbox_client)
75
76enum xgene_hwmon_version {
77 XGENE_HWMON_V1 = 0,
78 XGENE_HWMON_V2 = 1,
79};
80
81struct slimpro_resp_msg {
82 u32 msg;
83 u32 param1;
84 u32 param2;
85} __packed;
86
87struct xgene_hwmon_dev {
88 struct device *dev;
89 struct mbox_chan *mbox_chan;
90 struct pcc_mbox_chan *pcc_chan;
91 struct mbox_client mbox_client;
92 int mbox_idx;
93
94 spinlock_t kfifo_lock;
95 struct mutex rd_mutex;
96 struct completion rd_complete;
97 int resp_pending;
98 struct slimpro_resp_msg sync_msg;
99
100 struct work_struct workq;
101 struct kfifo_rec_ptr_1 async_msg_fifo;
102
103 struct device *hwmon_dev;
104 bool temp_critical_alarm;
105
106 phys_addr_t comm_base_addr;
107 void *pcc_comm_addr;
108 u64 usecs_lat;
109};
110
111/*
112 * This function tests and clears a bitmask then returns its old value
113 */
114static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask)
115{
116 u16 ret, val;
117
118 val = le16_to_cpu(READ_ONCE(*addr));
119 ret = val & mask;
120 val &= ~mask;
121 WRITE_ONCE(*addr, cpu_to_le16(val));
122
123 return ret;
124}
125
126static int xgene_hwmon_pcc_rd(struct xgene_hwmon_dev *ctx, u32 *msg)
127{
128 struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
129 u32 *ptr = (void *)(generic_comm_base + 1);
130 int rc, i;
131 u16 val;
132
133 mutex_lock(&ctx->rd_mutex);
134 init_completion(x: &ctx->rd_complete);
135 ctx->resp_pending = true;
136
137 /* Write signature for subspace */
138 WRITE_ONCE(generic_comm_base->signature,
139 cpu_to_le32(PCC_SIGNATURE | ctx->mbox_idx));
140
141 /* Write to the shared command region */
142 WRITE_ONCE(generic_comm_base->command,
143 cpu_to_le16(MSG_TYPE(msg[0]) | PCC_CMD_GENERATE_DB_INTR));
144
145 /* Flip CMD COMPLETE bit */
146 val = le16_to_cpu(READ_ONCE(generic_comm_base->status));
147 val &= ~PCC_STATUS_CMD_COMPLETE;
148 WRITE_ONCE(generic_comm_base->status, cpu_to_le16(val));
149
150 /* Copy the message to the PCC comm space */
151 for (i = 0; i < sizeof(struct slimpro_resp_msg) / 4; i++)
152 WRITE_ONCE(ptr[i], cpu_to_le32(msg[i]));
153
154 /* Ring the doorbell */
155 rc = mbox_send_message(chan: ctx->mbox_chan, mssg: msg);
156 if (rc < 0) {
157 dev_err(ctx->dev, "Mailbox send error %d\n", rc);
158 goto err;
159 }
160 if (!wait_for_completion_timeout(x: &ctx->rd_complete,
161 timeout: usecs_to_jiffies(u: ctx->usecs_lat))) {
162 dev_err(ctx->dev, "Mailbox operation timed out\n");
163 rc = -ETIMEDOUT;
164 goto err;
165 }
166
167 /* Check for error message */
168 if (MSG_TYPE(ctx->sync_msg.msg) == MSG_TYPE_ERR) {
169 rc = -EINVAL;
170 goto err;
171 }
172
173 msg[0] = ctx->sync_msg.msg;
174 msg[1] = ctx->sync_msg.param1;
175 msg[2] = ctx->sync_msg.param2;
176
177err:
178 mbox_chan_txdone(chan: ctx->mbox_chan, r: 0);
179 ctx->resp_pending = false;
180 mutex_unlock(lock: &ctx->rd_mutex);
181 return rc;
182}
183
184static int xgene_hwmon_rd(struct xgene_hwmon_dev *ctx, u32 *msg)
185{
186 int rc;
187
188 mutex_lock(&ctx->rd_mutex);
189 init_completion(x: &ctx->rd_complete);
190 ctx->resp_pending = true;
191
192 rc = mbox_send_message(chan: ctx->mbox_chan, mssg: msg);
193 if (rc < 0) {
194 dev_err(ctx->dev, "Mailbox send error %d\n", rc);
195 goto err;
196 }
197
198 if (!wait_for_completion_timeout(x: &ctx->rd_complete,
199 timeout: msecs_to_jiffies(MBOX_OP_TIMEOUTMS))) {
200 dev_err(ctx->dev, "Mailbox operation timed out\n");
201 rc = -ETIMEDOUT;
202 goto err;
203 }
204
205 /* Check for error message */
206 if (MSG_TYPE(ctx->sync_msg.msg) == MSG_TYPE_ERR) {
207 rc = -EINVAL;
208 goto err;
209 }
210
211 msg[0] = ctx->sync_msg.msg;
212 msg[1] = ctx->sync_msg.param1;
213 msg[2] = ctx->sync_msg.param2;
214
215err:
216 ctx->resp_pending = false;
217 mutex_unlock(lock: &ctx->rd_mutex);
218 return rc;
219}
220
221static int xgene_hwmon_reg_map_rd(struct xgene_hwmon_dev *ctx, u32 addr,
222 u32 *data)
223{
224 u32 msg[3];
225 int rc;
226
227 msg[0] = SENSOR_RD_MSG;
228 msg[1] = SENSOR_RD_EN_ADDR(addr);
229 msg[2] = 0;
230
231 if (acpi_disabled)
232 rc = xgene_hwmon_rd(ctx, msg);
233 else
234 rc = xgene_hwmon_pcc_rd(ctx, msg);
235
236 if (rc < 0)
237 return rc;
238
239 /*
240 * Check if sensor data is valid.
241 */
242 if (msg[1] & SENSOR_INVALID_DATA)
243 return -ENODATA;
244
245 *data = msg[1];
246
247 return rc;
248}
249
250static int xgene_hwmon_get_notification_msg(struct xgene_hwmon_dev *ctx,
251 u32 *amsg)
252{
253 u32 msg[3];
254 int rc;
255
256 msg[0] = TPC_EN_MSG(PWRMGMT_SUBTYPE_TPC, TPC_GET_ALARM, 0);
257 msg[1] = 0;
258 msg[2] = 0;
259
260 rc = xgene_hwmon_pcc_rd(ctx, msg);
261 if (rc < 0)
262 return rc;
263
264 amsg[0] = msg[0];
265 amsg[1] = msg[1];
266 amsg[2] = msg[2];
267
268 return rc;
269}
270
271static int xgene_hwmon_get_cpu_pwr(struct xgene_hwmon_dev *ctx, u32 *val)
272{
273 u32 watt, mwatt;
274 int rc;
275
276 rc = xgene_hwmon_reg_map_rd(ctx, PMD_PWR_REG, data: &watt);
277 if (rc < 0)
278 return rc;
279
280 rc = xgene_hwmon_reg_map_rd(ctx, PMD_PWR_MW_REG, data: &mwatt);
281 if (rc < 0)
282 return rc;
283
284 *val = WATT_TO_mWATT(watt) + mwatt;
285 return 0;
286}
287
288static int xgene_hwmon_get_io_pwr(struct xgene_hwmon_dev *ctx, u32 *val)
289{
290 u32 watt, mwatt;
291 int rc;
292
293 rc = xgene_hwmon_reg_map_rd(ctx, SOC_PWR_REG, data: &watt);
294 if (rc < 0)
295 return rc;
296
297 rc = xgene_hwmon_reg_map_rd(ctx, SOC_PWR_MW_REG, data: &mwatt);
298 if (rc < 0)
299 return rc;
300
301 *val = WATT_TO_mWATT(watt) + mwatt;
302 return 0;
303}
304
305static int xgene_hwmon_get_temp(struct xgene_hwmon_dev *ctx, u32 *val)
306{
307 return xgene_hwmon_reg_map_rd(ctx, SOC_TEMP_REG, data: val);
308}
309
310/*
311 * Sensor temperature/power functions
312 */
313static ssize_t temp1_input_show(struct device *dev,
314 struct device_attribute *attr,
315 char *buf)
316{
317 struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
318 int rc, temp;
319 u32 val;
320
321 rc = xgene_hwmon_get_temp(ctx, val: &val);
322 if (rc < 0)
323 return rc;
324
325 temp = sign_extend32(value: val, TEMP_NEGATIVE_BIT);
326
327 return sysfs_emit(buf, fmt: "%d\n", CELSIUS_TO_mCELSIUS(temp));
328}
329
330static ssize_t temp1_label_show(struct device *dev,
331 struct device_attribute *attr,
332 char *buf)
333{
334 return sysfs_emit(buf, fmt: "SoC Temperature\n");
335}
336
337static ssize_t temp1_critical_alarm_show(struct device *dev,
338 struct device_attribute *devattr,
339 char *buf)
340{
341 struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
342
343 return sysfs_emit(buf, fmt: "%d\n", ctx->temp_critical_alarm);
344}
345
346static ssize_t power1_label_show(struct device *dev,
347 struct device_attribute *attr,
348 char *buf)
349{
350 return sysfs_emit(buf, fmt: "CPU power\n");
351}
352
353static ssize_t power2_label_show(struct device *dev,
354 struct device_attribute *attr,
355 char *buf)
356{
357 return sysfs_emit(buf, fmt: "IO power\n");
358}
359
360static ssize_t power1_input_show(struct device *dev,
361 struct device_attribute *attr,
362 char *buf)
363{
364 struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
365 u32 val;
366 int rc;
367
368 rc = xgene_hwmon_get_cpu_pwr(ctx, val: &val);
369 if (rc < 0)
370 return rc;
371
372 return sysfs_emit(buf, fmt: "%u\n", mWATT_TO_uWATT(val));
373}
374
375static ssize_t power2_input_show(struct device *dev,
376 struct device_attribute *attr,
377 char *buf)
378{
379 struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
380 u32 val;
381 int rc;
382
383 rc = xgene_hwmon_get_io_pwr(ctx, val: &val);
384 if (rc < 0)
385 return rc;
386
387 return sysfs_emit(buf, fmt: "%u\n", mWATT_TO_uWATT(val));
388}
389
390static DEVICE_ATTR_RO(temp1_label);
391static DEVICE_ATTR_RO(temp1_input);
392static DEVICE_ATTR_RO(temp1_critical_alarm);
393static DEVICE_ATTR_RO(power1_label);
394static DEVICE_ATTR_RO(power1_input);
395static DEVICE_ATTR_RO(power2_label);
396static DEVICE_ATTR_RO(power2_input);
397
398static struct attribute *xgene_hwmon_attrs[] = {
399 &dev_attr_temp1_label.attr,
400 &dev_attr_temp1_input.attr,
401 &dev_attr_temp1_critical_alarm.attr,
402 &dev_attr_power1_label.attr,
403 &dev_attr_power1_input.attr,
404 &dev_attr_power2_label.attr,
405 &dev_attr_power2_input.attr,
406 NULL,
407};
408
409ATTRIBUTE_GROUPS(xgene_hwmon);
410
411static int xgene_hwmon_tpc_alarm(struct xgene_hwmon_dev *ctx,
412 struct slimpro_resp_msg *amsg)
413{
414 ctx->temp_critical_alarm = !!amsg->param2;
415 sysfs_notify(kobj: &ctx->dev->kobj, NULL, attr: "temp1_critical_alarm");
416
417 return 0;
418}
419
420static void xgene_hwmon_process_pwrmsg(struct xgene_hwmon_dev *ctx,
421 struct slimpro_resp_msg *amsg)
422{
423 if ((MSG_SUBTYPE(amsg->msg) == PWRMGMT_SUBTYPE_TPC) &&
424 (TPC_CMD(amsg->msg) == TPC_ALARM))
425 xgene_hwmon_tpc_alarm(ctx, amsg);
426}
427
428/*
429 * This function is called to process async work queue
430 */
431static void xgene_hwmon_evt_work(struct work_struct *work)
432{
433 struct slimpro_resp_msg amsg;
434 struct xgene_hwmon_dev *ctx;
435 int ret;
436
437 ctx = container_of(work, struct xgene_hwmon_dev, workq);
438 while (kfifo_out_spinlocked(&ctx->async_msg_fifo, &amsg,
439 sizeof(struct slimpro_resp_msg),
440 &ctx->kfifo_lock)) {
441 /*
442 * If PCC, send a consumer command to Platform to get info
443 * If Slimpro Mailbox, get message from specific FIFO
444 */
445 if (!acpi_disabled) {
446 ret = xgene_hwmon_get_notification_msg(ctx,
447 amsg: (u32 *)&amsg);
448 if (ret < 0)
449 continue;
450 }
451
452 if (MSG_TYPE(amsg.msg) == MSG_TYPE_PWRMGMT)
453 xgene_hwmon_process_pwrmsg(ctx, amsg: &amsg);
454 }
455}
456
457static int xgene_hwmon_rx_ready(struct xgene_hwmon_dev *ctx, void *msg)
458{
459 if (IS_ERR_OR_NULL(ptr: ctx->hwmon_dev) && !ctx->resp_pending) {
460 /* Enqueue to the FIFO */
461 kfifo_in_spinlocked(&ctx->async_msg_fifo, msg,
462 sizeof(struct slimpro_resp_msg),
463 &ctx->kfifo_lock);
464 return -ENODEV;
465 }
466
467 return 0;
468}
469
470/*
471 * This function is called when the SLIMpro Mailbox received a message
472 */
473static void xgene_hwmon_rx_cb(struct mbox_client *cl, void *msg)
474{
475 struct xgene_hwmon_dev *ctx = to_xgene_hwmon_dev(cl);
476
477 /*
478 * While the driver registers with the mailbox framework, an interrupt
479 * can be pending before the probe function completes its
480 * initialization. If such condition occurs, just queue up the message
481 * as the driver is not ready for servicing the callback.
482 */
483 if (xgene_hwmon_rx_ready(ctx, msg) < 0)
484 return;
485
486 /*
487 * Response message format:
488 * msg[0] is the return code of the operation
489 * msg[1] is the first parameter word
490 * msg[2] is the second parameter word
491 *
492 * As message only supports dword size, just assign it.
493 */
494
495 /* Check for sync query */
496 if (ctx->resp_pending &&
497 ((MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_ERR) ||
498 (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_DBG &&
499 MSG_SUBTYPE(((u32 *)msg)[0]) == DBG_SUBTYPE_SENSOR_READ) ||
500 (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_PWRMGMT &&
501 MSG_SUBTYPE(((u32 *)msg)[0]) == PWRMGMT_SUBTYPE_TPC &&
502 TPC_CMD(((u32 *)msg)[0]) == TPC_ALARM))) {
503 ctx->sync_msg.msg = ((u32 *)msg)[0];
504 ctx->sync_msg.param1 = ((u32 *)msg)[1];
505 ctx->sync_msg.param2 = ((u32 *)msg)[2];
506
507 /* Operation waiting for response */
508 complete(&ctx->rd_complete);
509
510 return;
511 }
512
513 /* Enqueue to the FIFO */
514 kfifo_in_spinlocked(&ctx->async_msg_fifo, msg,
515 sizeof(struct slimpro_resp_msg), &ctx->kfifo_lock);
516 /* Schedule the bottom handler */
517 schedule_work(work: &ctx->workq);
518}
519
520/*
521 * This function is called when the PCC Mailbox received a message
522 */
523static void xgene_hwmon_pcc_rx_cb(struct mbox_client *cl, void *msg)
524{
525 struct xgene_hwmon_dev *ctx = to_xgene_hwmon_dev(cl);
526 struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
527 struct slimpro_resp_msg amsg;
528
529 /*
530 * While the driver registers with the mailbox framework, an interrupt
531 * can be pending before the probe function completes its
532 * initialization. If such condition occurs, just queue up the message
533 * as the driver is not ready for servicing the callback.
534 */
535 if (xgene_hwmon_rx_ready(ctx, msg: &amsg) < 0)
536 return;
537
538 msg = generic_comm_base + 1;
539 /* Check if platform sends interrupt */
540 if (!xgene_word_tst_and_clr(addr: &generic_comm_base->status,
541 PCC_STATUS_SCI_DOORBELL))
542 return;
543
544 /*
545 * Response message format:
546 * msg[0] is the return code of the operation
547 * msg[1] is the first parameter word
548 * msg[2] is the second parameter word
549 *
550 * As message only supports dword size, just assign it.
551 */
552
553 /* Check for sync query */
554 if (ctx->resp_pending &&
555 ((MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_ERR) ||
556 (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_DBG &&
557 MSG_SUBTYPE(((u32 *)msg)[0]) == DBG_SUBTYPE_SENSOR_READ) ||
558 (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_PWRMGMT &&
559 MSG_SUBTYPE(((u32 *)msg)[0]) == PWRMGMT_SUBTYPE_TPC &&
560 TPC_CMD(((u32 *)msg)[0]) == TPC_ALARM))) {
561 /* Check if platform completes command */
562 if (xgene_word_tst_and_clr(addr: &generic_comm_base->status,
563 PCC_STATUS_CMD_COMPLETE)) {
564 ctx->sync_msg.msg = ((u32 *)msg)[0];
565 ctx->sync_msg.param1 = ((u32 *)msg)[1];
566 ctx->sync_msg.param2 = ((u32 *)msg)[2];
567
568 /* Operation waiting for response */
569 complete(&ctx->rd_complete);
570
571 return;
572 }
573 }
574
575 /*
576 * Platform notifies interrupt to OSPM.
577 * OPSM schedules a consumer command to get this information
578 * in a workqueue. Platform must wait until OSPM has issued
579 * a consumer command that serves this notification.
580 */
581
582 /* Enqueue to the FIFO */
583 kfifo_in_spinlocked(&ctx->async_msg_fifo, &amsg,
584 sizeof(struct slimpro_resp_msg), &ctx->kfifo_lock);
585 /* Schedule the bottom handler */
586 schedule_work(work: &ctx->workq);
587}
588
589static void xgene_hwmon_tx_done(struct mbox_client *cl, void *msg, int ret)
590{
591 if (ret) {
592 dev_dbg(cl->dev, "TX did not complete: CMD sent:%x, ret:%d\n",
593 *(u16 *)msg, ret);
594 } else {
595 dev_dbg(cl->dev, "TX completed. CMD sent:%x, ret:%d\n",
596 *(u16 *)msg, ret);
597 }
598}
599
600#ifdef CONFIG_ACPI
601static const struct acpi_device_id xgene_hwmon_acpi_match[] = {
602 {"APMC0D29", XGENE_HWMON_V1},
603 {"APMC0D8A", XGENE_HWMON_V2},
604 {},
605};
606MODULE_DEVICE_TABLE(acpi, xgene_hwmon_acpi_match);
607#endif
608
609static int xgene_hwmon_probe(struct platform_device *pdev)
610{
611 struct xgene_hwmon_dev *ctx;
612 struct mbox_client *cl;
613 int rc;
614
615 ctx = devm_kzalloc(dev: &pdev->dev, size: sizeof(*ctx), GFP_KERNEL);
616 if (!ctx)
617 return -ENOMEM;
618
619 ctx->dev = &pdev->dev;
620 platform_set_drvdata(pdev, data: ctx);
621 cl = &ctx->mbox_client;
622
623 spin_lock_init(&ctx->kfifo_lock);
624 mutex_init(&ctx->rd_mutex);
625
626 rc = kfifo_alloc(&ctx->async_msg_fifo,
627 sizeof(struct slimpro_resp_msg) * ASYNC_MSG_FIFO_SIZE,
628 GFP_KERNEL);
629 if (rc)
630 return -ENOMEM;
631
632 INIT_WORK(&ctx->workq, xgene_hwmon_evt_work);
633
634 /* Request mailbox channel */
635 cl->dev = &pdev->dev;
636 cl->tx_done = xgene_hwmon_tx_done;
637 cl->tx_block = false;
638 cl->tx_tout = MBOX_OP_TIMEOUTMS;
639 cl->knows_txdone = false;
640 if (acpi_disabled) {
641 cl->rx_callback = xgene_hwmon_rx_cb;
642 ctx->mbox_chan = mbox_request_channel(cl, index: 0);
643 if (IS_ERR(ptr: ctx->mbox_chan)) {
644 dev_err(&pdev->dev,
645 "SLIMpro mailbox channel request failed\n");
646 rc = -ENODEV;
647 goto out_mbox_free;
648 }
649 } else {
650 struct pcc_mbox_chan *pcc_chan;
651 const struct acpi_device_id *acpi_id;
652 int version;
653
654 acpi_id = acpi_match_device(ids: pdev->dev.driver->acpi_match_table,
655 dev: &pdev->dev);
656 if (!acpi_id) {
657 rc = -EINVAL;
658 goto out_mbox_free;
659 }
660
661 version = (int)acpi_id->driver_data;
662
663 if (device_property_read_u32(dev: &pdev->dev, propname: "pcc-channel",
664 val: &ctx->mbox_idx)) {
665 dev_err(&pdev->dev, "no pcc-channel property\n");
666 rc = -ENODEV;
667 goto out_mbox_free;
668 }
669
670 cl->rx_callback = xgene_hwmon_pcc_rx_cb;
671 pcc_chan = pcc_mbox_request_channel(cl, subspace_id: ctx->mbox_idx);
672 if (IS_ERR(ptr: pcc_chan)) {
673 dev_err(&pdev->dev,
674 "PPC channel request failed\n");
675 rc = -ENODEV;
676 goto out_mbox_free;
677 }
678
679 ctx->pcc_chan = pcc_chan;
680 ctx->mbox_chan = pcc_chan->mchan;
681
682 if (!ctx->mbox_chan->mbox->txdone_irq) {
683 dev_err(&pdev->dev, "PCC IRQ not supported\n");
684 rc = -ENODEV;
685 goto out;
686 }
687
688 /*
689 * This is the shared communication region
690 * for the OS and Platform to communicate over.
691 */
692 ctx->comm_base_addr = pcc_chan->shmem_base_addr;
693 if (ctx->comm_base_addr) {
694 if (version == XGENE_HWMON_V2)
695 ctx->pcc_comm_addr = (void __force *)devm_ioremap(dev: &pdev->dev,
696 offset: ctx->comm_base_addr,
697 size: pcc_chan->shmem_size);
698 else
699 ctx->pcc_comm_addr = devm_memremap(dev: &pdev->dev,
700 offset: ctx->comm_base_addr,
701 size: pcc_chan->shmem_size,
702 flags: MEMREMAP_WB);
703 } else {
704 dev_err(&pdev->dev, "Failed to get PCC comm region\n");
705 rc = -ENODEV;
706 goto out;
707 }
708
709 if (!ctx->pcc_comm_addr) {
710 dev_err(&pdev->dev,
711 "Failed to ioremap PCC comm region\n");
712 rc = -ENOMEM;
713 goto out;
714 }
715
716 /*
717 * pcc_chan->latency is just a Nominal value. In reality
718 * the remote processor could be much slower to reply.
719 * So add an arbitrary amount of wait on top of Nominal.
720 */
721 ctx->usecs_lat = PCC_NUM_RETRIES * pcc_chan->latency;
722 }
723
724 ctx->hwmon_dev = hwmon_device_register_with_groups(dev: ctx->dev,
725 name: "apm_xgene",
726 drvdata: ctx,
727 groups: xgene_hwmon_groups);
728 if (IS_ERR(ptr: ctx->hwmon_dev)) {
729 dev_err(&pdev->dev, "Failed to register HW monitor device\n");
730 rc = PTR_ERR(ptr: ctx->hwmon_dev);
731 goto out;
732 }
733
734 /*
735 * Schedule the bottom handler if there is a pending message.
736 */
737 schedule_work(work: &ctx->workq);
738
739 dev_info(&pdev->dev, "APM X-Gene SoC HW monitor driver registered\n");
740
741 return 0;
742
743out:
744 if (acpi_disabled)
745 mbox_free_channel(chan: ctx->mbox_chan);
746 else
747 pcc_mbox_free_channel(chan: ctx->pcc_chan);
748out_mbox_free:
749 kfifo_free(&ctx->async_msg_fifo);
750
751 return rc;
752}
753
754static void xgene_hwmon_remove(struct platform_device *pdev)
755{
756 struct xgene_hwmon_dev *ctx = platform_get_drvdata(pdev);
757
758 cancel_work_sync(work: &ctx->workq);
759 hwmon_device_unregister(dev: ctx->hwmon_dev);
760 kfifo_free(&ctx->async_msg_fifo);
761 if (acpi_disabled)
762 mbox_free_channel(chan: ctx->mbox_chan);
763 else
764 pcc_mbox_free_channel(chan: ctx->pcc_chan);
765}
766
767static const struct of_device_id xgene_hwmon_of_match[] = {
768 {.compatible = "apm,xgene-slimpro-hwmon"},
769 {}
770};
771MODULE_DEVICE_TABLE(of, xgene_hwmon_of_match);
772
773static struct platform_driver xgene_hwmon_driver = {
774 .probe = xgene_hwmon_probe,
775 .remove_new = xgene_hwmon_remove,
776 .driver = {
777 .name = "xgene-slimpro-hwmon",
778 .of_match_table = xgene_hwmon_of_match,
779 .acpi_match_table = ACPI_PTR(xgene_hwmon_acpi_match),
780 },
781};
782module_platform_driver(xgene_hwmon_driver);
783
784MODULE_DESCRIPTION("APM X-Gene SoC hardware monitor");
785MODULE_LICENSE("GPL");
786

source code of linux/drivers/hwmon/xgene-hwmon.c