Merge branch '2022-07-05-more-Kconfig-migrations' into next
[platform/kernel/u-boot.git] / drivers / misc / gsc.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2022 Gateworks Corporation
4  */
5
6 #include <command.h>
7 #include <gsc.h>
8 #include <i2c.h>
9 #include <rtc.h>
10 #include <asm/unaligned.h>
11 #include <linux/delay.h>
12 #include <dm/device.h>
13 #include <dm/device-internal.h>
14 #include <dm/ofnode.h>
15 #include <dm/read.h>
16
17 #define GSC_BUSNO       0
18 #define GSC_SC_ADDR     0x20
19 #define GSC_HWMON_ADDR  0x29
20 #define GSC_RTC_ADDR    0x68
21
22 /* System Controller registers */
23 enum {
24         GSC_SC_CTRL0            = 0,
25         GSC_SC_CTRL1            = 1,
26         GSC_SC_TIME             = 2,
27         GSC_SC_TIME_ADD         = 6,
28         GSC_SC_STATUS           = 10,
29         GSC_SC_FWCRC            = 12,
30         GSC_SC_FWVER            = 14,
31         GSC_SC_WP               = 15,
32         GSC_SC_RST_CAUSE        = 16,
33         GSC_SC_THERM_PROTECT    = 19,
34 };
35
36 /* System Controller Control1 bits */
37 enum {
38         GSC_SC_CTRL1_SLEEP_EN           = 0, /* 1 = enable sleep */
39         GSC_SC_CTRL1_SLEEP_ACTIVATE     = 1, /* 1 = activate sleep */
40         GSC_SC_CTRL1_SLEEP_ADD          = 2, /* 1 = latch and add sleep time */
41         GSC_SC_CTRL1_SLEEP_NOWAKEPB     = 3, /* 1 = do not wake on sleep on button press */
42         GSC_SC_CTRL1_WDTIME             = 4, /* 1 = 60s timeout, 0 = 30s timeout */
43         GSC_SC_CTRL1_WDEN               = 5, /* 1 = enable, 0 = disable */
44         GSC_SC_CTRL1_BOOT_CHK           = 6, /* 1 = enable alt boot check */
45         GSC_SC_CTRL1_WDDIS              = 7, /* 1 = disable boot watchdog */
46 };
47
48 /* System Controller Interrupt bits */
49 enum {
50         GSC_SC_IRQ_PB           = 0, /* Pushbutton switch */
51         GSC_SC_IRQ_SECURE       = 1, /* Secure Key erase operation complete */
52         GSC_SC_IRQ_EEPROM_WP    = 2, /* EEPROM write violation */
53         GSC_SC_IRQ_GPIO         = 4, /* GPIO change */
54         GSC_SC_IRQ_TAMPER       = 5, /* Tamper detect */
55         GSC_SC_IRQ_WATCHDOG     = 6, /* Watchdog trip */
56         GSC_SC_IRQ_PBLONG       = 7, /* Pushbutton long hold */
57 };
58
59 /* System Controller WP bits */
60 enum {
61         GSC_SC_WP_ALL           = 0, /* Write Protect All EEPROM regions */
62         GSC_SC_WP_BOARDINFO     = 1, /* Write Protect Board Info region */
63 };
64
65 /* System Controller Reset Cause */
66 enum {
67         GSC_SC_RST_CAUSE_VIN            = 0,
68         GSC_SC_RST_CAUSE_PB             = 1,
69         GSC_SC_RST_CAUSE_WDT            = 2,
70         GSC_SC_RST_CAUSE_CPU            = 3,
71         GSC_SC_RST_CAUSE_TEMP_LOCAL     = 4,
72         GSC_SC_RST_CAUSE_TEMP_REMOTE    = 5,
73         GSC_SC_RST_CAUSE_SLEEP          = 6,
74         GSC_SC_RST_CAUSE_BOOT_WDT       = 7,
75         GSC_SC_RST_CAUSE_BOOT_WDT_MAN   = 8,
76         GSC_SC_RST_CAUSE_SOFT_PWR       = 9,
77         GSC_SC_RST_CAUSE_MAX            = 10,
78 };
79
80 #if (IS_ENABLED(CONFIG_DM_I2C))
81
82 struct gsc_priv {
83         int gscver;
84         int fwver;
85         int fwcrc;
86         struct udevice *hwmon;
87         struct udevice *rtc;
88 };
89
90 /*
91  * GSCv2 will fail to ACK an I2C transaction if it is busy, which can occur
92  * during its 1HZ timer tick while reading ADC's. When this does occur,
93  * it will never be busy longer than 2 back-to-back transfers so retry 3 times.
94  */
95 static int gsc_i2c_read(struct udevice *dev, uint addr, u8 *buf, int len)
96 {
97         struct gsc_priv *priv = dev_get_priv(dev);
98         int retry = (priv->gscver == 3) ? 1 : 3;
99         int n = 0;
100         int ret;
101
102         while (n++ < retry) {
103                 ret = dm_i2c_read(dev, addr, buf, len);
104                 if (!ret)
105                         break;
106                 if (ret != -EREMOTEIO)
107                         break;
108                 mdelay(10);
109         }
110         return ret;
111 }
112
113 static int gsc_i2c_write(struct udevice *dev, uint addr, const u8 *buf, int len)
114 {
115         struct gsc_priv *priv = dev_get_priv(dev);
116         int retry = (priv->gscver == 3) ? 1 : 3;
117         int n = 0;
118         int ret;
119
120         while (n++ < retry) {
121                 ret = dm_i2c_write(dev, addr, buf, len);
122                 if (!ret)
123                         break;
124                 if (ret != -EREMOTEIO)
125                         break;
126                 mdelay(10);
127         }
128         return ret;
129 }
130
131 static struct udevice *gsc_get_dev(int busno, int slave)
132 {
133         struct udevice *dev, *bus;
134         int ret;
135
136         ret = uclass_get_device_by_seq(UCLASS_I2C, busno, &bus);
137         if (ret)
138                 return NULL;
139         ret = dm_i2c_probe(bus, slave, 0, &dev);
140         if (ret)
141                 return NULL;
142
143         return dev;
144 }
145
146 static int gsc_thermal_get_info(struct udevice *dev, u8 *outreg, int *tmax, bool *enable)
147 {
148         struct gsc_priv *priv = dev_get_priv(dev);
149         int ret;
150         u8 reg;
151
152         if (priv->gscver > 2 && priv->fwver > 52) {
153                 ret = gsc_i2c_read(dev, GSC_SC_THERM_PROTECT, &reg, 1);
154                 if (!ret) {
155                         if (outreg)
156                                 *outreg = reg;
157                         if (tmax) {
158                                 *tmax = ((reg & 0xf8) >> 3) * 2;
159                                 if (*tmax)
160                                         *tmax += 70;
161                                 else
162                                         *tmax = 120;
163                         }
164                         if (enable)
165                                 *enable = reg & 1;
166                 }
167         } else {
168                 ret = -ENODEV;
169         }
170
171         return ret;
172 }
173
174 static int gsc_thermal_get_temp(struct udevice *dev)
175 {
176         struct gsc_priv *priv = dev_get_priv(dev);
177         u32 reg, mode, val;
178         const char *label;
179         ofnode node;
180         u8 buf[2];
181
182         ofnode_for_each_subnode(node, dev_read_subnode(dev, "adc")) {
183                 if (ofnode_read_u32(node, "reg", &reg))
184                         reg = -1;
185                 if (ofnode_read_u32(node, "gw,mode", &mode))
186                         mode = -1;
187                 label = ofnode_read_string(node, "label");
188
189                 if ((reg == -1) || (mode == -1) || !label)
190                         continue;
191
192                 if (mode != 0 || strcmp(label, "temp"))
193                         continue;
194
195                 memset(buf, 0, sizeof(buf));
196                 if (!gsc_i2c_read(priv->hwmon, reg, buf, sizeof(buf))) {
197                         val = buf[0] | buf[1] << 8;
198                         if (val > 0x8000)
199                                 val -= 0xffff;
200                         return val;
201                 }
202         }
203
204         return 0;
205 }
206
207 static void gsc_thermal_info(struct udevice *dev)
208 {
209         struct gsc_priv *priv = dev_get_priv(dev);
210
211         switch (priv->gscver) {
212         case 2:
213                 printf("board_temp:%dC ", gsc_thermal_get_temp(dev) / 10);
214                 break;
215         case 3:
216                 if (priv->fwver > 52) {
217                         bool enabled;
218                         int tmax;
219
220                         if (!gsc_thermal_get_info(dev, NULL, &tmax, &enabled)) {
221                                 puts("Thermal protection:");
222                                 if (enabled)
223                                         printf("enabled at %dC ", tmax);
224                                 else
225                                         puts("disabled ");
226                         }
227                 }
228                 break;
229         }
230 }
231
232 static void gsc_reset_info(struct udevice *dev)
233 {
234         struct gsc_priv *priv = dev_get_priv(dev);
235         static const char * const names[] = {
236                 "VIN",
237                 "PB",
238                 "WDT",
239                 "CPU",
240                 "TEMP_L",
241                 "TEMP_R",
242                 "SLEEP",
243                 "BOOT_WDT1",
244                 "BOOT_WDT2",
245                 "SOFT_PWR",
246         };
247         u8 reg;
248
249         /* reset cause */
250         switch (priv->gscver) {
251         case 2:
252                 if (!gsc_i2c_read(dev, GSC_SC_STATUS, &reg, 1)) {
253                         if (reg & BIT(GSC_SC_IRQ_WATCHDOG)) {
254                                 puts("RST:WDT");
255                                 reg &= ~BIT(GSC_SC_IRQ_WATCHDOG);
256                                 gsc_i2c_write(dev, GSC_SC_STATUS, &reg, 1);
257                         } else {
258                                 puts("RST:VIN");
259                         }
260                         printf(" WDT:%sabled ",
261                                (reg & BIT(GSC_SC_CTRL1_WDEN)) ? "en" : "dis");
262                 }
263                 break;
264         case 3:
265                 if (priv->fwver > 52 &&
266                     !gsc_i2c_read(dev, GSC_SC_RST_CAUSE, &reg, 1)) {
267                         puts("RST:");
268                         if (reg < ARRAY_SIZE(names))
269                                 printf("%s ", names[reg]);
270                         else
271                                 printf("0x%02x ", reg);
272                 }
273                 break;
274         }
275 }
276
277 /* display hardware monitor ADC channels */
278 static int gsc_hwmon(struct udevice *dev)
279 {
280         struct gsc_priv *priv = dev_get_priv(dev);
281         u32 reg, mode, val, offset;
282         const char *label;
283         ofnode node;
284         u8 buf[2];
285         u32 r[2];
286         int ret;
287
288         /* iterate over hwmon nodes */
289         ofnode_for_each_subnode(node, dev_read_subnode(dev, "adc")) {
290                 if (ofnode_read_u32(node, "reg", &reg))
291                         reg = -1;
292                 if (ofnode_read_u32(node, "gw,mode", &mode))
293                         mode = -1;
294                 label = ofnode_read_string(node, "label");
295                 if ((reg == -1) || (mode == -1) || !label)
296                         continue;
297
298                 memset(buf, 0, sizeof(buf));
299                 ret = gsc_i2c_read(priv->hwmon, reg, buf, sizeof(buf));
300                 if (ret) {
301                         printf("i2c error: %d\n", ret);
302                         continue;
303                 }
304                 val = buf[0] | buf[1] << 8;
305
306                 switch (mode) {
307                 case 0: /* temperature (C*10) */
308                         if (val > 0x8000)
309                                 val -= 0xffff;
310                         printf("%-8s: %d.%ldC\n", label, val / 10, abs(val % 10));
311                         break;
312                 case 1: /* prescaled voltage */
313                         if (val != 0xffff)
314                                 printf("%-8s: %d.%03dV\n", label, val / 1000, val % 1000);
315                         break;
316                 case 2: /* scaled based on ref volt and resolution */
317                         val *= 2500;
318                         val /= 1 << 12;
319
320                         /* apply pre-scaler voltage divider */
321                         if (!ofnode_read_u32_index(node, "gw,voltage-divider-ohms", 0, &r[0]) &&
322                             !ofnode_read_u32_index(node, "gw,voltage-divider-ohms", 1, &r[1]) &&
323                             r[0] && r[1]) {
324                                 val *= (r[0] + r[1]);
325                                 val /= r[1];
326                         }
327
328                         /* adjust by offset */
329                         val += (offset / 1000);
330
331                         printf("%-8s: %d.%03dV\n", label, val / 1000, val % 1000);
332                         break;
333                 }
334         }
335
336         return 0;
337 }
338
339 static int gsc_banner(struct udevice *dev)
340 {
341         struct gsc_priv *priv = dev_get_priv(dev);
342
343         /* banner */
344         printf("GSCv%d   : v%d 0x%04x ", priv->gscver, priv->fwver, priv->fwcrc);
345         gsc_reset_info(dev);
346         gsc_thermal_info(dev);
347         puts("\n");
348
349         /* Display RTC */
350         if (priv->rtc) {
351                 u8 buf[4];
352                 time_t timestamp;
353                 struct rtc_time tm;
354
355                 if (!gsc_i2c_read(priv->rtc, 0, buf, 4)) {
356                         timestamp = get_unaligned_le32(buf);
357                         rtc_to_tm(timestamp, &tm);
358                         printf("RTC     : %4d-%02d-%02d  %2d:%02d:%02d UTC\n",
359                                tm.tm_year, tm.tm_mon, tm.tm_mday,
360                                tm.tm_hour, tm.tm_min, tm.tm_sec);
361                 }
362         }
363
364         return 0;
365 }
366
367 static int gsc_probe(struct udevice *dev)
368 {
369         struct gsc_priv *priv = dev_get_priv(dev);
370         u8 buf[32];
371         int ret;
372
373         ret = gsc_i2c_read(dev, 0, buf, sizeof(buf));
374         if (ret)
375                 return ret;
376
377         /*
378          * GSC chip version:
379          *   GSCv2 has 16 registers (which overlap)
380          *   GSCv3 has 32 registers
381          */
382         priv->gscver = memcmp(buf, buf + 16, 16) ? 3 : 2;
383         priv->fwver = buf[GSC_SC_FWVER];
384         priv->fwcrc = buf[GSC_SC_FWCRC] | buf[GSC_SC_FWCRC + 1] << 8;
385         priv->hwmon = gsc_get_dev(GSC_BUSNO, GSC_HWMON_ADDR);
386         if (priv->hwmon)
387                 dev_set_priv(priv->hwmon, priv);
388         priv->rtc = gsc_get_dev(GSC_BUSNO, GSC_RTC_ADDR);
389         if (priv->rtc)
390                 dev_set_priv(priv->rtc, priv);
391
392 #ifdef CONFIG_SPL_BUILD
393         gsc_banner(dev);
394 #endif
395
396         return 0;
397 };
398
399 static const struct udevice_id gsc_ids[] = {
400         { .compatible = "gw,gsc", },
401         { }
402 };
403
404 U_BOOT_DRIVER(gsc) = {
405         .name = "gsc",
406         .id = UCLASS_MISC,
407         .of_match = gsc_ids,
408         .probe = gsc_probe,
409         .priv_auto      = sizeof(struct gsc_priv),
410         .flags = DM_FLAG_PRE_RELOC,
411 };
412
413 static int gsc_sleep(struct udevice *dev, unsigned long secs)
414 {
415         u8 regs[4];
416         int ret;
417
418         printf("GSC Sleeping for %ld seconds\n", secs);
419         put_unaligned_le32(secs, regs);
420         ret = gsc_i2c_write(dev, GSC_SC_TIME_ADD, regs, sizeof(regs));
421         if (ret)
422                 goto err;
423         ret = gsc_i2c_read(dev, GSC_SC_CTRL1, regs, 1);
424         if (ret)
425                 goto err;
426         regs[0] |= BIT(GSC_SC_CTRL1_SLEEP_ADD);
427         ret = gsc_i2c_write(dev, GSC_SC_CTRL1, regs, 1);
428         if (ret)
429                 goto err;
430         regs[0] &= ~BIT(GSC_SC_CTRL1_SLEEP_ADD);
431         regs[0] |= BIT(GSC_SC_CTRL1_SLEEP_EN) | BIT(GSC_SC_CTRL1_SLEEP_ACTIVATE);
432         ret = gsc_i2c_write(dev, GSC_SC_CTRL1, regs, 1);
433         if (ret)
434                 goto err;
435
436         return 0;
437
438 err:
439         printf("i2c error: %d\n", ret);
440         return ret;
441 }
442
443 static int gsc_wd_disable(struct udevice *dev)
444 {
445         int ret;
446         u8 reg;
447
448         ret = gsc_i2c_read(dev, GSC_SC_CTRL1, &reg, 1);
449         if (ret)
450                 goto err;
451         reg |= BIT(GSC_SC_CTRL1_WDDIS);
452         reg &= ~BIT(GSC_SC_CTRL1_BOOT_CHK);
453         ret = gsc_i2c_write(dev, GSC_SC_CTRL1, &reg, 1);
454         if (ret)
455                 goto err;
456         puts("GSC     : boot watchdog disabled\n");
457
458         return 0;
459
460 err:
461         puts("i2c error");
462         return ret;
463 }
464
465 static int gsc_thermal(struct udevice *dev, const char *cmd, const char *val)
466 {
467         struct gsc_priv *priv = dev_get_priv(dev);
468         int ret, tmax;
469         bool enabled;
470         u8 reg;
471
472         if (priv->gscver < 3 || priv->fwver < 53)
473                 return -EINVAL;
474         ret = gsc_thermal_get_info(dev, &reg, &tmax, &enabled);
475         if (ret)
476                 return ret;
477         if (cmd && !strcmp(cmd, "enable")) {
478                 if (val && *val) {
479                         tmax = clamp((int)simple_strtoul(val, NULL, 0), 72, 122);
480                         reg &= ~0xf8;
481                         reg |= ((tmax - 70) / 2) << 3;
482                 }
483                 reg |= BIT(0);
484                 gsc_i2c_write(dev, GSC_SC_THERM_PROTECT, &reg, 1);
485         } else if (cmd && !strcmp(cmd, "disable")) {
486                 reg &= ~BIT(0);
487                 gsc_i2c_write(dev, GSC_SC_THERM_PROTECT, &reg, 1);
488         } else if (cmd) {
489                 return -EINVAL;
490         }
491
492         /* show status */
493         gsc_thermal_info(dev);
494         puts("\n");
495
496         return 0;
497 }
498
499 /* override in board files to display additional board EEPROM info */
500 __weak void board_gsc_info(void)
501 {
502 }
503
504 static void gsc_info(struct udevice *dev)
505 {
506         gsc_banner(dev);
507         board_gsc_info();
508 }
509
510 static int do_gsc(struct cmd_tbl *cmdtp, int flag, int argc, char * const argv[])
511 {
512         struct udevice *dev;
513         int ret;
514
515         /* get/probe driver */
516         ret = uclass_get_device_by_driver(UCLASS_MISC, DM_DRIVER_GET(gsc), &dev);
517         if (ret)
518                 return CMD_RET_USAGE;
519         if (argc < 2) {
520                 gsc_info(dev);
521                 return CMD_RET_SUCCESS;
522         } else if (strcasecmp(argv[1], "sleep") == 0) {
523                 if (argc < 3)
524                         return CMD_RET_USAGE;
525                 if (!gsc_sleep(dev, dectoul(argv[2], NULL)))
526                         return CMD_RET_SUCCESS;
527         } else if (strcasecmp(argv[1], "hwmon") == 0) {
528                 if (!gsc_hwmon(dev))
529                         return CMD_RET_SUCCESS;
530         } else if (strcasecmp(argv[1], "wd-disable") == 0) {
531                 if (!gsc_wd_disable(dev))
532                         return CMD_RET_SUCCESS;
533         } else if (strcasecmp(argv[1], "thermal") == 0) {
534                 char *cmd, *val;
535
536                 cmd = (argc > 2) ? argv[2] : NULL;
537                 val = (argc > 3) ? argv[3] : NULL;
538                 if (!gsc_thermal(dev, cmd, val))
539                         return CMD_RET_SUCCESS;
540         }
541
542         return CMD_RET_USAGE;
543 }
544
545 U_BOOT_CMD(gsc, 4, 1, do_gsc, "Gateworks System Controller",
546            "[sleep <secs>]|[hwmon]|[wd-disable][thermal [disable|enable [temp]]]\n");
547
548 /* disable boot watchdog - useful for an SPL that wants to use falcon mode */
549 int gsc_boot_wd_disable(void)
550 {
551         struct udevice *dev;
552         int ret;
553
554         /* get/probe driver */
555         ret = uclass_get_device_by_driver(UCLASS_MISC, DM_DRIVER_GET(gsc), &dev);
556         if (!ret)
557                 ret = gsc_wd_disable(dev);
558
559         return ret;
560 }
561
562 # else
563
564 /*
565  * GSCv2 will fail to ACK an I2C transaction if it is busy, which can occur
566  * during its 1HZ timer tick while reading ADC's. When this does occur,
567  * it will never be busy longer than 2 back-to-back transfers so retry 3 times.
568  */
569 static int gsc_i2c_read(uint chip, uint addr, u8 *buf, int len)
570 {
571         int retry = 3;
572         int n = 0;
573         int ret;
574
575         while (n++ < retry) {
576                 ret = i2c_read(chip, addr, 1, buf, len);
577                 if (!ret)
578                         break;
579                 if (ret != -EREMOTEIO)
580                         break;
581 printf("%s 0x%02x retry %d\n", __func__, addr, n);
582                 mdelay(10);
583         }
584         return ret;
585 }
586
587 static int gsc_i2c_write(uint chip, uint addr, u8 *buf, int len)
588 {
589         int retry = 3;
590         int n = 0;
591         int ret;
592
593         while (n++ < retry) {
594                 ret = i2c_write(chip, addr, 1, buf, len);
595                 if (!ret)
596                         break;
597                 if (ret != -EREMOTEIO)
598                         break;
599 printf("%s 0x%02x retry %d\n", __func__, addr, n);
600                 mdelay(10);
601         }
602         return ret;
603 }
604
605 /* disable boot watchdog - useful for an SPL that wants to use falcon mode */
606 int gsc_boot_wd_disable(void)
607 {
608         u8 buf[32];
609         int ret;
610
611         i2c_set_bus_num(GSC_BUSNO);
612         ret = gsc_i2c_read(GSC_SC_ADDR, 0, buf, sizeof(buf));
613         if (!ret) {
614                 buf[GSC_SC_CTRL1] |= BIT(GSC_SC_CTRL1_WDDIS);
615                 ret = gsc_i2c_write(GSC_SC_ADDR, GSC_SC_CTRL1, &buf[GSC_SC_CTRL1], 1);
616                 printf("GSCv%d: v%d 0x%04x ",
617                        memcmp(buf, buf + 16, 16) ? 3 : 2,
618                        buf[GSC_SC_FWVER],
619                        buf[GSC_SC_FWCRC] | buf[GSC_SC_FWCRC + 1] << 8);
620                 if (buf[GSC_SC_STATUS] & BIT(GSC_SC_IRQ_WATCHDOG)) {
621                         puts("RST:WDT ");
622                         buf[GSC_SC_STATUS] &= ~BIT(GSC_SC_IRQ_WATCHDOG);
623                         gsc_i2c_write(GSC_SC_ADDR, GSC_SC_STATUS, &buf[GSC_SC_STATUS], 1);
624                 } else {
625                         puts("RST:VIN ");
626                 }
627                 puts("WDT:disabled\n");
628         }
629
630         return ret;
631 }
632
633 #endif