1/*
2 * APM X-Gene SoC Hardware Monitoring Driver
3 *
4 * Copyright (c) 2016, Applied Micro Circuits Corporation
5 * Author: Loc Ho <lho@apm.com>
6 * Hoan Tran <hotran@apm.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 *
21 * This driver provides the following features:
22 * - Retrieve CPU total power (uW)
23 * - Retrieve IO total power (uW)
24 * - Retrieve SoC temperature (milli-degree C) and alarm
25 */
26#include <linux/acpi.h>
27#include <linux/dma-mapping.h>
28#include <linux/hwmon.h>
29#include <linux/hwmon-sysfs.h>
30#include <linux/io.h>
31#include <linux/interrupt.h>
32#include <linux/kfifo.h>
33#include <linux/mailbox_controller.h>
34#include <linux/mailbox_client.h>
35#include <linux/module.h>
36#include <linux/of.h>
37#include <linux/platform_device.h>
38
39#include <acpi/pcc.h>
40
41/* SLIMpro message defines */
42#define MSG_TYPE_DBG 0
43#define MSG_TYPE_ERR 7
44#define MSG_TYPE_PWRMGMT 9
45
46#define MSG_TYPE(v) (((v) & 0xF0000000) >> 28)
47#define MSG_TYPE_SET(v) (((v) << 28) & 0xF0000000)
48#define MSG_SUBTYPE(v) (((v) & 0x0F000000) >> 24)
49#define MSG_SUBTYPE_SET(v) (((v) << 24) & 0x0F000000)
50
51#define DBG_SUBTYPE_SENSOR_READ 4
52#define SENSOR_RD_MSG 0x04FFE902
53#define SENSOR_RD_EN_ADDR(a) ((a) & 0x000FFFFF)
54#define PMD_PWR_REG 0x20
55#define PMD_PWR_MW_REG 0x26
56#define SOC_PWR_REG 0x21
57#define SOC_PWR_MW_REG 0x27
58#define SOC_TEMP_REG 0x10
59
60#define TEMP_NEGATIVE_BIT 8
61#define SENSOR_INVALID_DATA BIT(15)
62
63#define PWRMGMT_SUBTYPE_TPC 1
64#define TPC_ALARM 2
65#define TPC_GET_ALARM 3
66#define TPC_CMD(v) (((v) & 0x00FF0000) >> 16)
67#define TPC_CMD_SET(v) (((v) << 16) & 0x00FF0000)
68#define TPC_EN_MSG(hndl, cmd, type) \
69 (MSG_TYPE_SET(MSG_TYPE_PWRMGMT) | \
70 MSG_SUBTYPE_SET(hndl) | TPC_CMD_SET(cmd) | type)
71
72/* PCC defines */
73#define PCC_SIGNATURE_MASK 0x50424300
74#define PCCC_GENERATE_DB_INT BIT(15)
75#define PCCS_CMD_COMPLETE BIT(0)
76#define PCCS_SCI_DOORBEL BIT(1)
77#define PCCS_PLATFORM_NOTIFICATION BIT(3)
78/*
79 * Arbitrary retries in case the remote processor is slow to respond
80 * to PCC commands
81 */
82#define PCC_NUM_RETRIES 500
83
84#define ASYNC_MSG_FIFO_SIZE 16
85#define MBOX_OP_TIMEOUTMS 1000
86
87#define WATT_TO_mWATT(x) ((x) * 1000)
88#define mWATT_TO_uWATT(x) ((x) * 1000)
89#define CELSIUS_TO_mCELSIUS(x) ((x) * 1000)
90
91#define to_xgene_hwmon_dev(cl) \
92 container_of(cl, struct xgene_hwmon_dev, mbox_client)
93
94enum xgene_hwmon_version {
95 XGENE_HWMON_V1 = 0,
96 XGENE_HWMON_V2 = 1,
97};
98
99struct slimpro_resp_msg {
100 u32 msg;
101 u32 param1;
102 u32 param2;
103} __packed;
104
105struct xgene_hwmon_dev {
106 struct device *dev;
107 struct mbox_chan *mbox_chan;
108 struct mbox_client mbox_client;
109 int mbox_idx;
110
111 spinlock_t kfifo_lock;
112 struct mutex rd_mutex;
113 struct completion rd_complete;
114 int resp_pending;
115 struct slimpro_resp_msg sync_msg;
116
117 struct work_struct workq;
118 struct kfifo_rec_ptr_1 async_msg_fifo;
119
120 struct device *hwmon_dev;
121 bool temp_critical_alarm;
122
123 phys_addr_t comm_base_addr;
124 void *pcc_comm_addr;
125 u64 usecs_lat;
126};
127
128/*
129 * This function tests and clears a bitmask then returns its old value
130 */
131static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask)
132{
133 u16 ret, val;
134
135 val = le16_to_cpu(READ_ONCE(*addr));
136 ret = val & mask;
137 val &= ~mask;
138 WRITE_ONCE(*addr, cpu_to_le16(val));
139
140 return ret;
141}
142
143static int xgene_hwmon_pcc_rd(struct xgene_hwmon_dev *ctx, u32 *msg)
144{
145 struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
146 u32 *ptr = (void *)(generic_comm_base + 1);
147 int rc, i;
148 u16 val;
149
150 mutex_lock(&ctx->rd_mutex);
151 init_completion(&ctx->rd_complete);
152 ctx->resp_pending = true;
153
154 /* Write signature for subspace */
155 WRITE_ONCE(generic_comm_base->signature,
156 cpu_to_le32(PCC_SIGNATURE_MASK | ctx->mbox_idx));
157
158 /* Write to the shared command region */
159 WRITE_ONCE(generic_comm_base->command,
160 cpu_to_le16(MSG_TYPE(msg[0]) | PCCC_GENERATE_DB_INT));
161
162 /* Flip CMD COMPLETE bit */
163 val = le16_to_cpu(READ_ONCE(generic_comm_base->status));
164 val &= ~PCCS_CMD_COMPLETE;
165 WRITE_ONCE(generic_comm_base->status, cpu_to_le16(val));
166
167 /* Copy the message to the PCC comm space */
168 for (i = 0; i < sizeof(struct slimpro_resp_msg) / 4; i++)
169 WRITE_ONCE(ptr[i], cpu_to_le32(msg[i]));
170
171 /* Ring the doorbell */
172 rc = mbox_send_message(ctx->mbox_chan, msg);
173 if (rc < 0) {
174 dev_err(ctx->dev, "Mailbox send error %d\n", rc);
175 goto err;
176 }
177 if (!wait_for_completion_timeout(&ctx->rd_complete,
178 usecs_to_jiffies(ctx->usecs_lat))) {
179 dev_err(ctx->dev, "Mailbox operation timed out\n");
180 rc = -ETIMEDOUT;
181 goto err;
182 }
183
184 /* Check for error message */
185 if (MSG_TYPE(ctx->sync_msg.msg) == MSG_TYPE_ERR) {
186 rc = -EINVAL;
187 goto err;
188 }
189
190 msg[0] = ctx->sync_msg.msg;
191 msg[1] = ctx->sync_msg.param1;
192 msg[2] = ctx->sync_msg.param2;
193
194err:
195 mbox_chan_txdone(ctx->mbox_chan, 0);
196 ctx->resp_pending = false;
197 mutex_unlock(&ctx->rd_mutex);
198 return rc;
199}
200
201static int xgene_hwmon_rd(struct xgene_hwmon_dev *ctx, u32 *msg)
202{
203 int rc;
204
205 mutex_lock(&ctx->rd_mutex);
206 init_completion(&ctx->rd_complete);
207 ctx->resp_pending = true;
208
209 rc = mbox_send_message(ctx->mbox_chan, msg);
210 if (rc < 0) {
211 dev_err(ctx->dev, "Mailbox send error %d\n", rc);
212 goto err;
213 }
214
215 if (!wait_for_completion_timeout(&ctx->rd_complete,
216 msecs_to_jiffies(MBOX_OP_TIMEOUTMS))) {
217 dev_err(ctx->dev, "Mailbox operation timed out\n");
218 rc = -ETIMEDOUT;
219 goto err;
220 }
221
222 /* Check for error message */
223 if (MSG_TYPE(ctx->sync_msg.msg) == MSG_TYPE_ERR) {
224 rc = -EINVAL;
225 goto err;
226 }
227
228 msg[0] = ctx->sync_msg.msg;
229 msg[1] = ctx->sync_msg.param1;
230 msg[2] = ctx->sync_msg.param2;
231
232err:
233 ctx->resp_pending = false;
234 mutex_unlock(&ctx->rd_mutex);
235 return rc;
236}
237
238static int xgene_hwmon_reg_map_rd(struct xgene_hwmon_dev *ctx, u32 addr,
239 u32 *data)
240{
241 u32 msg[3];
242 int rc;
243
244 msg[0] = SENSOR_RD_MSG;
245 msg[1] = SENSOR_RD_EN_ADDR(addr);
246 msg[2] = 0;
247
248 if (acpi_disabled)
249 rc = xgene_hwmon_rd(ctx, msg);
250 else
251 rc = xgene_hwmon_pcc_rd(ctx, msg);
252
253 if (rc < 0)
254 return rc;
255
256 /*
257 * Check if sensor data is valid.
258 */
259 if (msg[1] & SENSOR_INVALID_DATA)
260 return -ENODATA;
261
262 *data = msg[1];
263
264 return rc;
265}
266
267static int xgene_hwmon_get_notification_msg(struct xgene_hwmon_dev *ctx,
268 u32 *amsg)
269{
270 u32 msg[3];
271 int rc;
272
273 msg[0] = TPC_EN_MSG(PWRMGMT_SUBTYPE_TPC, TPC_GET_ALARM, 0);
274 msg[1] = 0;
275 msg[2] = 0;
276
277 rc = xgene_hwmon_pcc_rd(ctx, msg);
278 if (rc < 0)
279 return rc;
280
281 amsg[0] = msg[0];
282 amsg[1] = msg[1];
283 amsg[2] = msg[2];
284
285 return rc;
286}
287
288static int xgene_hwmon_get_cpu_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, PMD_PWR_REG, &watt);
294 if (rc < 0)
295 return rc;
296
297 rc = xgene_hwmon_reg_map_rd(ctx, PMD_PWR_MW_REG, &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_io_pwr(struct xgene_hwmon_dev *ctx, u32 *val)
306{
307 u32 watt, mwatt;
308 int rc;
309
310 rc = xgene_hwmon_reg_map_rd(ctx, SOC_PWR_REG, &watt);
311 if (rc < 0)
312 return rc;
313
314 rc = xgene_hwmon_reg_map_rd(ctx, SOC_PWR_MW_REG, &mwatt);
315 if (rc < 0)
316 return rc;
317
318 *val = WATT_TO_mWATT(watt) + mwatt;
319 return 0;
320}
321
322static int xgene_hwmon_get_temp(struct xgene_hwmon_dev *ctx, u32 *val)
323{
324 return xgene_hwmon_reg_map_rd(ctx, SOC_TEMP_REG, val);
325}
326
327/*
328 * Sensor temperature/power functions
329 */
330static ssize_t temp1_input_show(struct device *dev,
331 struct device_attribute *attr,
332 char *buf)
333{
334 struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
335 int rc, temp;
336 u32 val;
337
338 rc = xgene_hwmon_get_temp(ctx, &val);
339 if (rc < 0)
340 return rc;
341
342 temp = sign_extend32(val, TEMP_NEGATIVE_BIT);
343
344 return snprintf(buf, PAGE_SIZE, "%d\n", CELSIUS_TO_mCELSIUS(temp));
345}
346
347static ssize_t temp1_label_show(struct device *dev,
348 struct device_attribute *attr,
349 char *buf)
350{
351 return snprintf(buf, PAGE_SIZE, "SoC Temperature\n");
352}
353
354static ssize_t temp1_critical_alarm_show(struct device *dev,
355 struct device_attribute *devattr,
356 char *buf)
357{
358 struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
359
360 return snprintf(buf, PAGE_SIZE, "%d\n", ctx->temp_critical_alarm);
361}
362
363static ssize_t power1_label_show(struct device *dev,
364 struct device_attribute *attr,
365 char *buf)
366{
367 return snprintf(buf, PAGE_SIZE, "CPU power\n");
368}
369
370static ssize_t power2_label_show(struct device *dev,
371 struct device_attribute *attr,
372 char *buf)
373{
374 return snprintf(buf, PAGE_SIZE, "IO power\n");
375}
376
377static ssize_t power1_input_show(struct device *dev,
378 struct device_attribute *attr,
379 char *buf)
380{
381 struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
382 u32 val;
383 int rc;
384
385 rc = xgene_hwmon_get_cpu_pwr(ctx, &val);
386 if (rc < 0)
387 return rc;
388
389 return snprintf(buf, PAGE_SIZE, "%u\n", mWATT_TO_uWATT(val));
390}
391
392static ssize_t power2_input_show(struct device *dev,
393 struct device_attribute *attr,
394 char *buf)
395{
396 struct xgene_hwmon_dev *ctx = dev_get_drvdata(dev);
397 u32 val;
398 int rc;
399
400 rc = xgene_hwmon_get_io_pwr(ctx, &val);
401 if (rc < 0)
402 return rc;
403
404 return snprintf(buf, PAGE_SIZE, "%u\n", mWATT_TO_uWATT(val));
405}
406
407static DEVICE_ATTR_RO(temp1_label);
408static DEVICE_ATTR_RO(temp1_input);
409static DEVICE_ATTR_RO(temp1_critical_alarm);
410static DEVICE_ATTR_RO(power1_label);
411static DEVICE_ATTR_RO(power1_input);
412static DEVICE_ATTR_RO(power2_label);
413static DEVICE_ATTR_RO(power2_input);
414
415static struct attribute *xgene_hwmon_attrs[] = {
416 &dev_attr_temp1_label.attr,
417 &dev_attr_temp1_input.attr,
418 &dev_attr_temp1_critical_alarm.attr,
419 &dev_attr_power1_label.attr,
420 &dev_attr_power1_input.attr,
421 &dev_attr_power2_label.attr,
422 &dev_attr_power2_input.attr,
423 NULL,
424};
425
426ATTRIBUTE_GROUPS(xgene_hwmon);
427
428static int xgene_hwmon_tpc_alarm(struct xgene_hwmon_dev *ctx,
429 struct slimpro_resp_msg *amsg)
430{
431 ctx->temp_critical_alarm = !!amsg->param2;
432 sysfs_notify(&ctx->dev->kobj, NULL, "temp1_critical_alarm");
433
434 return 0;
435}
436
437static void xgene_hwmon_process_pwrmsg(struct xgene_hwmon_dev *ctx,
438 struct slimpro_resp_msg *amsg)
439{
440 if ((MSG_SUBTYPE(amsg->msg) == PWRMGMT_SUBTYPE_TPC) &&
441 (TPC_CMD(amsg->msg) == TPC_ALARM))
442 xgene_hwmon_tpc_alarm(ctx, amsg);
443}
444
445/*
446 * This function is called to process async work queue
447 */
448static void xgene_hwmon_evt_work(struct work_struct *work)
449{
450 struct slimpro_resp_msg amsg;
451 struct xgene_hwmon_dev *ctx;
452 int ret;
453
454 ctx = container_of(work, struct xgene_hwmon_dev, workq);
455 while (kfifo_out_spinlocked(&ctx->async_msg_fifo, &amsg,
456 sizeof(struct slimpro_resp_msg),
457 &ctx->kfifo_lock)) {
458 /*
459 * If PCC, send a consumer command to Platform to get info
460 * If Slimpro Mailbox, get message from specific FIFO
461 */
462 if (!acpi_disabled) {
463 ret = xgene_hwmon_get_notification_msg(ctx,
464 (u32 *)&amsg);
465 if (ret < 0)
466 continue;
467 }
468
469 if (MSG_TYPE(amsg.msg) == MSG_TYPE_PWRMGMT)
470 xgene_hwmon_process_pwrmsg(ctx, &amsg);
471 }
472}
473
474static int xgene_hwmon_rx_ready(struct xgene_hwmon_dev *ctx, void *msg)
475{
476 if (IS_ERR_OR_NULL(ctx->hwmon_dev) && !ctx->resp_pending) {
477 /* Enqueue to the FIFO */
478 kfifo_in_spinlocked(&ctx->async_msg_fifo, msg,
479 sizeof(struct slimpro_resp_msg),
480 &ctx->kfifo_lock);
481 return -ENODEV;
482 }
483
484 return 0;
485}
486
487/*
488 * This function is called when the SLIMpro Mailbox received a message
489 */
490static void xgene_hwmon_rx_cb(struct mbox_client *cl, void *msg)
491{
492 struct xgene_hwmon_dev *ctx = to_xgene_hwmon_dev(cl);
493
494 /*
495 * While the driver registers with the mailbox framework, an interrupt
496 * can be pending before the probe function completes its
497 * initialization. If such condition occurs, just queue up the message
498 * as the driver is not ready for servicing the callback.
499 */
500 if (xgene_hwmon_rx_ready(ctx, msg) < 0)
501 return;
502
503 /*
504 * Response message format:
505 * msg[0] is the return code of the operation
506 * msg[1] is the first parameter word
507 * msg[2] is the second parameter word
508 *
509 * As message only supports dword size, just assign it.
510 */
511
512 /* Check for sync query */
513 if (ctx->resp_pending &&
514 ((MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_ERR) ||
515 (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_DBG &&
516 MSG_SUBTYPE(((u32 *)msg)[0]) == DBG_SUBTYPE_SENSOR_READ) ||
517 (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_PWRMGMT &&
518 MSG_SUBTYPE(((u32 *)msg)[0]) == PWRMGMT_SUBTYPE_TPC &&
519 TPC_CMD(((u32 *)msg)[0]) == TPC_ALARM))) {
520 ctx->sync_msg.msg = ((u32 *)msg)[0];
521 ctx->sync_msg.param1 = ((u32 *)msg)[1];
522 ctx->sync_msg.param2 = ((u32 *)msg)[2];
523
524 /* Operation waiting for response */
525 complete(&ctx->rd_complete);
526
527 return;
528 }
529
530 /* Enqueue to the FIFO */
531 kfifo_in_spinlocked(&ctx->async_msg_fifo, msg,
532 sizeof(struct slimpro_resp_msg), &ctx->kfifo_lock);
533 /* Schedule the bottom handler */
534 schedule_work(&ctx->workq);
535}
536
537/*
538 * This function is called when the PCC Mailbox received a message
539 */
540static void xgene_hwmon_pcc_rx_cb(struct mbox_client *cl, void *msg)
541{
542 struct xgene_hwmon_dev *ctx = to_xgene_hwmon_dev(cl);
543 struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
544 struct slimpro_resp_msg amsg;
545
546 /*
547 * While the driver registers with the mailbox framework, an interrupt
548 * can be pending before the probe function completes its
549 * initialization. If such condition occurs, just queue up the message
550 * as the driver is not ready for servicing the callback.
551 */
552 if (xgene_hwmon_rx_ready(ctx, &amsg) < 0)
553 return;
554
555 msg = generic_comm_base + 1;
556 /* Check if platform sends interrupt */
557 if (!xgene_word_tst_and_clr(&generic_comm_base->status,
558 PCCS_SCI_DOORBEL))
559 return;
560
561 /*
562 * Response message format:
563 * msg[0] is the return code of the operation
564 * msg[1] is the first parameter word
565 * msg[2] is the second parameter word
566 *
567 * As message only supports dword size, just assign it.
568 */
569
570 /* Check for sync query */
571 if (ctx->resp_pending &&
572 ((MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_ERR) ||
573 (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_DBG &&
574 MSG_SUBTYPE(((u32 *)msg)[0]) == DBG_SUBTYPE_SENSOR_READ) ||
575 (MSG_TYPE(((u32 *)msg)[0]) == MSG_TYPE_PWRMGMT &&
576 MSG_SUBTYPE(((u32 *)msg)[0]) == PWRMGMT_SUBTYPE_TPC &&
577 TPC_CMD(((u32 *)msg)[0]) == TPC_ALARM))) {
578 /* Check if platform completes command */
579 if (xgene_word_tst_and_clr(&generic_comm_base->status,
580 PCCS_CMD_COMPLETE)) {
581 ctx->sync_msg.msg = ((u32 *)msg)[0];
582 ctx->sync_msg.param1 = ((u32 *)msg)[1];
583 ctx->sync_msg.param2 = ((u32 *)msg)[2];
584
585 /* Operation waiting for response */
586 complete(&ctx->rd_complete);
587
588 return;
589 }
590 }
591
592 /*
593 * Platform notifies interrupt to OSPM.
594 * OPSM schedules a consumer command to get this information
595 * in a workqueue. Platform must wait until OSPM has issued
596 * a consumer command that serves this notification.
597 */
598
599 /* Enqueue to the FIFO */
600 kfifo_in_spinlocked(&ctx->async_msg_fifo, &amsg,
601 sizeof(struct slimpro_resp_msg), &ctx->kfifo_lock);
602 /* Schedule the bottom handler */
603 schedule_work(&ctx->workq);
604}
605
606static void xgene_hwmon_tx_done(struct mbox_client *cl, void *msg, int ret)
607{
608 if (ret) {
609 dev_dbg(cl->dev, "TX did not complete: CMD sent:%x, ret:%d\n",
610 *(u16 *)msg, ret);
611 } else {
612 dev_dbg(cl->dev, "TX completed. CMD sent:%x, ret:%d\n",
613 *(u16 *)msg, ret);
614 }
615}
616
617#ifdef CONFIG_ACPI
618static const struct acpi_device_id xgene_hwmon_acpi_match[] = {
619 {"APMC0D29", XGENE_HWMON_V1},
620 {"APMC0D8A", XGENE_HWMON_V2},
621 {},
622};
623MODULE_DEVICE_TABLE(acpi, xgene_hwmon_acpi_match);
624#endif
625
626static int xgene_hwmon_probe(struct platform_device *pdev)
627{
628 struct xgene_hwmon_dev *ctx;
629 struct mbox_client *cl;
630 int rc;
631
632 ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
633 if (!ctx)
634 return -ENOMEM;
635
636 ctx->dev = &pdev->dev;
637 platform_set_drvdata(pdev, ctx);
638 cl = &ctx->mbox_client;
639
640 spin_lock_init(&ctx->kfifo_lock);
641 mutex_init(&ctx->rd_mutex);
642
643 rc = kfifo_alloc(&ctx->async_msg_fifo,
644 sizeof(struct slimpro_resp_msg) * ASYNC_MSG_FIFO_SIZE,
645 GFP_KERNEL);
646 if (rc)
647 return -ENOMEM;
648
649 INIT_WORK(&ctx->workq, xgene_hwmon_evt_work);
650
651 /* Request mailbox channel */
652 cl->dev = &pdev->dev;
653 cl->tx_done = xgene_hwmon_tx_done;
654 cl->tx_block = false;
655 cl->tx_tout = MBOX_OP_TIMEOUTMS;
656 cl->knows_txdone = false;
657 if (acpi_disabled) {
658 cl->rx_callback = xgene_hwmon_rx_cb;
659 ctx->mbox_chan = mbox_request_channel(cl, 0);
660 if (IS_ERR(ctx->mbox_chan)) {
661 dev_err(&pdev->dev,
662 "SLIMpro mailbox channel request failed\n");
663 rc = -ENODEV;
664 goto out_mbox_free;
665 }
666 } else {
667 struct acpi_pcct_hw_reduced *cppc_ss;
668 const struct acpi_device_id *acpi_id;
669 int version;
670
671 acpi_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
672 &pdev->dev);
673 if (!acpi_id)
674 return -EINVAL;
675
676 version = (int)acpi_id->driver_data;
677
678 if (device_property_read_u32(&pdev->dev, "pcc-channel",
679 &ctx->mbox_idx)) {
680 dev_err(&pdev->dev, "no pcc-channel property\n");
681 rc = -ENODEV;
682 goto out_mbox_free;
683 }
684
685 cl->rx_callback = xgene_hwmon_pcc_rx_cb;
686 ctx->mbox_chan = pcc_mbox_request_channel(cl, ctx->mbox_idx);
687 if (IS_ERR(ctx->mbox_chan)) {
688 dev_err(&pdev->dev,
689 "PPC channel request failed\n");
690 rc = -ENODEV;
691 goto out_mbox_free;
692 }
693
694 /*
695 * The PCC mailbox controller driver should
696 * have parsed the PCCT (global table of all
697 * PCC channels) and stored pointers to the
698 * subspace communication region in con_priv.
699 */
700 cppc_ss = ctx->mbox_chan->con_priv;
701 if (!cppc_ss) {
702 dev_err(&pdev->dev, "PPC subspace not found\n");
703 rc = -ENODEV;
704 goto out;
705 }
706
707 if (!ctx->mbox_chan->mbox->txdone_irq) {
708 dev_err(&pdev->dev, "PCC IRQ not supported\n");
709 rc = -ENODEV;
710 goto out;
711 }
712
713 /*
714 * This is the shared communication region
715 * for the OS and Platform to communicate over.
716 */
717 ctx->comm_base_addr = cppc_ss->base_address;
718 if (ctx->comm_base_addr) {
719 if (version == XGENE_HWMON_V2)
720 ctx->pcc_comm_addr = (void __force *)ioremap(
721 ctx->comm_base_addr,
722 cppc_ss->length);
723 else
724 ctx->pcc_comm_addr = memremap(
725 ctx->comm_base_addr,
726 cppc_ss->length,
727 MEMREMAP_WB);
728 } else {
729 dev_err(&pdev->dev, "Failed to get PCC comm region\n");
730 rc = -ENODEV;
731 goto out;
732 }
733
734 if (!ctx->pcc_comm_addr) {
735 dev_err(&pdev->dev,
736 "Failed to ioremap PCC comm region\n");
737 rc = -ENOMEM;
738 goto out;
739 }
740
741 /*
742 * cppc_ss->latency is just a Nominal value. In reality
743 * the remote processor could be much slower to reply.
744 * So add an arbitrary amount of wait on top of Nominal.
745 */
746 ctx->usecs_lat = PCC_NUM_RETRIES * cppc_ss->latency;
747 }
748
749 ctx->hwmon_dev = hwmon_device_register_with_groups(ctx->dev,
750 "apm_xgene",
751 ctx,
752 xgene_hwmon_groups);
753 if (IS_ERR(ctx->hwmon_dev)) {
754 dev_err(&pdev->dev, "Failed to register HW monitor device\n");
755 rc = PTR_ERR(ctx->hwmon_dev);
756 goto out;
757 }
758
759 /*
760 * Schedule the bottom handler if there is a pending message.
761 */
762 schedule_work(&ctx->workq);
763
764 dev_info(&pdev->dev, "APM X-Gene SoC HW monitor driver registered\n");
765
766 return 0;
767
768out:
769 if (acpi_disabled)
770 mbox_free_channel(ctx->mbox_chan);
771 else
772 pcc_mbox_free_channel(ctx->mbox_chan);
773out_mbox_free:
774 kfifo_free(&ctx->async_msg_fifo);
775
776 return rc;
777}
778
779static int xgene_hwmon_remove(struct platform_device *pdev)
780{
781 struct xgene_hwmon_dev *ctx = platform_get_drvdata(pdev);
782
783 hwmon_device_unregister(ctx->hwmon_dev);
784 kfifo_free(&ctx->async_msg_fifo);
785 if (acpi_disabled)
786 mbox_free_channel(ctx->mbox_chan);
787 else
788 pcc_mbox_free_channel(ctx->mbox_chan);
789
790 return 0;
791}
792
793static const struct of_device_id xgene_hwmon_of_match[] = {
794 {.compatible = "apm,xgene-slimpro-hwmon"},
795 {}
796};
797MODULE_DEVICE_TABLE(of, xgene_hwmon_of_match);
798
799static struct platform_driver xgene_hwmon_driver __refdata = {
800 .probe = xgene_hwmon_probe,
801 .remove = xgene_hwmon_remove,
802 .driver = {
803 .name = "xgene-slimpro-hwmon",
804 .of_match_table = xgene_hwmon_of_match,
805 .acpi_match_table = ACPI_PTR(xgene_hwmon_acpi_match),
806 },
807};
808module_platform_driver(xgene_hwmon_driver);
809
810MODULE_DESCRIPTION("APM X-Gene SoC hardware monitor");
811MODULE_LICENSE("GPL");
812