1d5bb994bSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
216b1d26eSNeelesh Gupta /*
316b1d26eSNeelesh Gupta * IBM OPAL RTC driver
416b1d26eSNeelesh Gupta * Copyright (C) 2014 IBM
516b1d26eSNeelesh Gupta */
616b1d26eSNeelesh Gupta
7a737e835SJoe Perches #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8a737e835SJoe Perches
916b1d26eSNeelesh Gupta #define DRVNAME "rtc-opal"
1016b1d26eSNeelesh Gupta
1116b1d26eSNeelesh Gupta #include <linux/module.h>
1216b1d26eSNeelesh Gupta #include <linux/err.h>
1316b1d26eSNeelesh Gupta #include <linux/rtc.h>
1416b1d26eSNeelesh Gupta #include <linux/delay.h>
1516b1d26eSNeelesh Gupta #include <linux/bcd.h>
1616b1d26eSNeelesh Gupta #include <linux/platform_device.h>
1716b1d26eSNeelesh Gupta #include <linux/of.h>
1816b1d26eSNeelesh Gupta #include <asm/opal.h>
1916b1d26eSNeelesh Gupta #include <asm/firmware.h>
2016b1d26eSNeelesh Gupta
opal_to_tm(u32 y_m_d,u64 h_m_s_ms,struct rtc_time * tm)2116b1d26eSNeelesh Gupta static void opal_to_tm(u32 y_m_d, u64 h_m_s_ms, struct rtc_time *tm)
2216b1d26eSNeelesh Gupta {
2316b1d26eSNeelesh Gupta tm->tm_year = ((bcd2bin(y_m_d >> 24) * 100) +
2416b1d26eSNeelesh Gupta bcd2bin((y_m_d >> 16) & 0xff)) - 1900;
2516b1d26eSNeelesh Gupta tm->tm_mon = bcd2bin((y_m_d >> 8) & 0xff) - 1;
2616b1d26eSNeelesh Gupta tm->tm_mday = bcd2bin(y_m_d & 0xff);
2716b1d26eSNeelesh Gupta tm->tm_hour = bcd2bin((h_m_s_ms >> 56) & 0xff);
2816b1d26eSNeelesh Gupta tm->tm_min = bcd2bin((h_m_s_ms >> 48) & 0xff);
2916b1d26eSNeelesh Gupta tm->tm_sec = bcd2bin((h_m_s_ms >> 40) & 0xff);
3016b1d26eSNeelesh Gupta
3100b912b0SDaniel Axtens tm->tm_wday = -1;
3216b1d26eSNeelesh Gupta }
3316b1d26eSNeelesh Gupta
tm_to_opal(struct rtc_time * tm,u32 * y_m_d,u64 * h_m_s_ms)3416b1d26eSNeelesh Gupta static void tm_to_opal(struct rtc_time *tm, u32 *y_m_d, u64 *h_m_s_ms)
3516b1d26eSNeelesh Gupta {
3616b1d26eSNeelesh Gupta *y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) / 100)) << 24;
3716b1d26eSNeelesh Gupta *y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) % 100)) << 16;
3816b1d26eSNeelesh Gupta *y_m_d |= ((u32)bin2bcd((tm->tm_mon + 1))) << 8;
3916b1d26eSNeelesh Gupta *y_m_d |= ((u32)bin2bcd(tm->tm_mday));
4016b1d26eSNeelesh Gupta
4116b1d26eSNeelesh Gupta *h_m_s_ms |= ((u64)bin2bcd(tm->tm_hour)) << 56;
4216b1d26eSNeelesh Gupta *h_m_s_ms |= ((u64)bin2bcd(tm->tm_min)) << 48;
4316b1d26eSNeelesh Gupta *h_m_s_ms |= ((u64)bin2bcd(tm->tm_sec)) << 40;
4416b1d26eSNeelesh Gupta }
4516b1d26eSNeelesh Gupta
opal_get_rtc_time(struct device * dev,struct rtc_time * tm)4616b1d26eSNeelesh Gupta static int opal_get_rtc_time(struct device *dev, struct rtc_time *tm)
4716b1d26eSNeelesh Gupta {
48682e6b4dSNicholas Piggin s64 rc = OPAL_BUSY;
495b8b5806SStewart Smith int retries = 10;
5016b1d26eSNeelesh Gupta u32 y_m_d;
5116b1d26eSNeelesh Gupta u64 h_m_s_ms;
5216b1d26eSNeelesh Gupta __be32 __y_m_d;
5316b1d26eSNeelesh Gupta __be64 __h_m_s_ms;
5416b1d26eSNeelesh Gupta
5516b1d26eSNeelesh Gupta while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
5616b1d26eSNeelesh Gupta rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms);
57682e6b4dSNicholas Piggin if (rc == OPAL_BUSY_EVENT) {
58682e6b4dSNicholas Piggin msleep(OPAL_BUSY_DELAY_MS);
5916b1d26eSNeelesh Gupta opal_poll_events(NULL);
60682e6b4dSNicholas Piggin } else if (rc == OPAL_BUSY) {
61682e6b4dSNicholas Piggin msleep(OPAL_BUSY_DELAY_MS);
62682e6b4dSNicholas Piggin } else if (rc == OPAL_HARDWARE || rc == OPAL_INTERNAL_ERROR) {
63682e6b4dSNicholas Piggin if (retries--) {
64682e6b4dSNicholas Piggin msleep(10); /* Wait 10ms before retry */
65682e6b4dSNicholas Piggin rc = OPAL_BUSY; /* go around again */
66682e6b4dSNicholas Piggin }
67682e6b4dSNicholas Piggin }
6816b1d26eSNeelesh Gupta }
6916b1d26eSNeelesh Gupta
7016b1d26eSNeelesh Gupta if (rc != OPAL_SUCCESS)
7116b1d26eSNeelesh Gupta return -EIO;
7216b1d26eSNeelesh Gupta
7316b1d26eSNeelesh Gupta y_m_d = be32_to_cpu(__y_m_d);
7416b1d26eSNeelesh Gupta h_m_s_ms = be64_to_cpu(__h_m_s_ms);
7516b1d26eSNeelesh Gupta opal_to_tm(y_m_d, h_m_s_ms, tm);
7616b1d26eSNeelesh Gupta
7716b1d26eSNeelesh Gupta return 0;
7816b1d26eSNeelesh Gupta }
7916b1d26eSNeelesh Gupta
opal_set_rtc_time(struct device * dev,struct rtc_time * tm)8016b1d26eSNeelesh Gupta static int opal_set_rtc_time(struct device *dev, struct rtc_time *tm)
8116b1d26eSNeelesh Gupta {
82682e6b4dSNicholas Piggin s64 rc = OPAL_BUSY;
835b8b5806SStewart Smith int retries = 10;
8416b1d26eSNeelesh Gupta u32 y_m_d = 0;
8516b1d26eSNeelesh Gupta u64 h_m_s_ms = 0;
8616b1d26eSNeelesh Gupta
8716b1d26eSNeelesh Gupta tm_to_opal(tm, &y_m_d, &h_m_s_ms);
88682e6b4dSNicholas Piggin
8916b1d26eSNeelesh Gupta while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
9016b1d26eSNeelesh Gupta rc = opal_rtc_write(y_m_d, h_m_s_ms);
91682e6b4dSNicholas Piggin if (rc == OPAL_BUSY_EVENT) {
92682e6b4dSNicholas Piggin msleep(OPAL_BUSY_DELAY_MS);
9316b1d26eSNeelesh Gupta opal_poll_events(NULL);
94682e6b4dSNicholas Piggin } else if (rc == OPAL_BUSY) {
95682e6b4dSNicholas Piggin msleep(OPAL_BUSY_DELAY_MS);
96682e6b4dSNicholas Piggin } else if (rc == OPAL_HARDWARE || rc == OPAL_INTERNAL_ERROR) {
97682e6b4dSNicholas Piggin if (retries--) {
98682e6b4dSNicholas Piggin msleep(10); /* Wait 10ms before retry */
99682e6b4dSNicholas Piggin rc = OPAL_BUSY; /* go around again */
100682e6b4dSNicholas Piggin }
101682e6b4dSNicholas Piggin }
10216b1d26eSNeelesh Gupta }
10316b1d26eSNeelesh Gupta
10416b1d26eSNeelesh Gupta return rc == OPAL_SUCCESS ? 0 : -EIO;
10516b1d26eSNeelesh Gupta }
10616b1d26eSNeelesh Gupta
10716b1d26eSNeelesh Gupta /*
10816b1d26eSNeelesh Gupta * TPO Timed Power-On
10916b1d26eSNeelesh Gupta *
11016b1d26eSNeelesh Gupta * TPO get/set OPAL calls care about the hour and min and to make it consistent
11116b1d26eSNeelesh Gupta * with the rtc utility time conversion functions, we use the 'u64' to store
11216b1d26eSNeelesh Gupta * its value and perform bit shift by 32 before use..
11316b1d26eSNeelesh Gupta */
opal_get_tpo_time(struct device * dev,struct rtc_wkalrm * alarm)11416b1d26eSNeelesh Gupta static int opal_get_tpo_time(struct device *dev, struct rtc_wkalrm *alarm)
11516b1d26eSNeelesh Gupta {
11616b1d26eSNeelesh Gupta __be32 __y_m_d, __h_m;
11716b1d26eSNeelesh Gupta struct opal_msg msg;
11816b1d26eSNeelesh Gupta int rc, token;
11916b1d26eSNeelesh Gupta u64 h_m_s_ms;
12016b1d26eSNeelesh Gupta u32 y_m_d;
12116b1d26eSNeelesh Gupta
12216b1d26eSNeelesh Gupta token = opal_async_get_token_interruptible();
12316b1d26eSNeelesh Gupta if (token < 0) {
12416b1d26eSNeelesh Gupta if (token != -ERESTARTSYS)
12516b1d26eSNeelesh Gupta pr_err("Failed to get the async token\n");
12616b1d26eSNeelesh Gupta
12716b1d26eSNeelesh Gupta return token;
12816b1d26eSNeelesh Gupta }
12916b1d26eSNeelesh Gupta
13016b1d26eSNeelesh Gupta rc = opal_tpo_read(token, &__y_m_d, &__h_m);
13116b1d26eSNeelesh Gupta if (rc != OPAL_ASYNC_COMPLETION) {
13216b1d26eSNeelesh Gupta rc = -EIO;
13316b1d26eSNeelesh Gupta goto exit;
13416b1d26eSNeelesh Gupta }
13516b1d26eSNeelesh Gupta
13616b1d26eSNeelesh Gupta rc = opal_async_wait_response(token, &msg);
13716b1d26eSNeelesh Gupta if (rc) {
13816b1d26eSNeelesh Gupta rc = -EIO;
13916b1d26eSNeelesh Gupta goto exit;
14016b1d26eSNeelesh Gupta }
14116b1d26eSNeelesh Gupta
142d0226d31SSuraj Jitindar Singh rc = opal_get_async_rc(msg);
14316b1d26eSNeelesh Gupta if (rc != OPAL_SUCCESS) {
14416b1d26eSNeelesh Gupta rc = -EIO;
14516b1d26eSNeelesh Gupta goto exit;
14616b1d26eSNeelesh Gupta }
14716b1d26eSNeelesh Gupta
14816b1d26eSNeelesh Gupta y_m_d = be32_to_cpu(__y_m_d);
14916b1d26eSNeelesh Gupta h_m_s_ms = ((u64)be32_to_cpu(__h_m) << 32);
1506dc1cf6fSVaibhav Jain
1516dc1cf6fSVaibhav Jain /* check if no alarm is set */
1526dc1cf6fSVaibhav Jain if (y_m_d == 0 && h_m_s_ms == 0) {
1536dc1cf6fSVaibhav Jain pr_debug("No alarm is set\n");
1546dc1cf6fSVaibhav Jain rc = -ENOENT;
1556dc1cf6fSVaibhav Jain goto exit;
1566dc1cf6fSVaibhav Jain } else {
1576dc1cf6fSVaibhav Jain pr_debug("Alarm set to %x %llx\n", y_m_d, h_m_s_ms);
1586dc1cf6fSVaibhav Jain }
1596dc1cf6fSVaibhav Jain
16016b1d26eSNeelesh Gupta opal_to_tm(y_m_d, h_m_s_ms, &alarm->time);
16116b1d26eSNeelesh Gupta
16216b1d26eSNeelesh Gupta exit:
16316b1d26eSNeelesh Gupta opal_async_release_token(token);
16416b1d26eSNeelesh Gupta return rc;
16516b1d26eSNeelesh Gupta }
16616b1d26eSNeelesh Gupta
16716b1d26eSNeelesh Gupta /* Set Timed Power-On */
opal_set_tpo_time(struct device * dev,struct rtc_wkalrm * alarm)16816b1d26eSNeelesh Gupta static int opal_set_tpo_time(struct device *dev, struct rtc_wkalrm *alarm)
16916b1d26eSNeelesh Gupta {
170c3530094SAndrzej Hajda u64 h_m_s_ms = 0;
17116b1d26eSNeelesh Gupta struct opal_msg msg;
17216b1d26eSNeelesh Gupta u32 y_m_d = 0;
173c3530094SAndrzej Hajda int token, rc;
17416b1d26eSNeelesh Gupta
1750ec7769aSVaibhav Jain /* if alarm is enabled */
1760ec7769aSVaibhav Jain if (alarm->enabled) {
17716b1d26eSNeelesh Gupta tm_to_opal(&alarm->time, &y_m_d, &h_m_s_ms);
1780ec7769aSVaibhav Jain pr_debug("Alarm set to %x %llx\n", y_m_d, h_m_s_ms);
1790ec7769aSVaibhav Jain
1800ec7769aSVaibhav Jain } else {
1810ec7769aSVaibhav Jain pr_debug("Alarm getting disabled\n");
1820ec7769aSVaibhav Jain }
18316b1d26eSNeelesh Gupta
18416b1d26eSNeelesh Gupta token = opal_async_get_token_interruptible();
18516b1d26eSNeelesh Gupta if (token < 0) {
18616b1d26eSNeelesh Gupta if (token != -ERESTARTSYS)
18716b1d26eSNeelesh Gupta pr_err("Failed to get the async token\n");
18816b1d26eSNeelesh Gupta
18916b1d26eSNeelesh Gupta return token;
19016b1d26eSNeelesh Gupta }
19116b1d26eSNeelesh Gupta
19216b1d26eSNeelesh Gupta /* TPO, we care about hour and minute */
19316b1d26eSNeelesh Gupta rc = opal_tpo_write(token, y_m_d,
19416b1d26eSNeelesh Gupta (u32)((h_m_s_ms >> 32) & 0xffff0000));
19516b1d26eSNeelesh Gupta if (rc != OPAL_ASYNC_COMPLETION) {
19616b1d26eSNeelesh Gupta rc = -EIO;
19716b1d26eSNeelesh Gupta goto exit;
19816b1d26eSNeelesh Gupta }
19916b1d26eSNeelesh Gupta
20016b1d26eSNeelesh Gupta rc = opal_async_wait_response(token, &msg);
20116b1d26eSNeelesh Gupta if (rc) {
20216b1d26eSNeelesh Gupta rc = -EIO;
20316b1d26eSNeelesh Gupta goto exit;
20416b1d26eSNeelesh Gupta }
20516b1d26eSNeelesh Gupta
206d0226d31SSuraj Jitindar Singh rc = opal_get_async_rc(msg);
20716b1d26eSNeelesh Gupta if (rc != OPAL_SUCCESS)
20816b1d26eSNeelesh Gupta rc = -EIO;
20916b1d26eSNeelesh Gupta
21016b1d26eSNeelesh Gupta exit:
21116b1d26eSNeelesh Gupta opal_async_release_token(token);
21216b1d26eSNeelesh Gupta return rc;
21316b1d26eSNeelesh Gupta }
21416b1d26eSNeelesh Gupta
opal_tpo_alarm_irq_enable(struct device * dev,unsigned int enabled)215fd86b2d4SYueHaibing static int opal_tpo_alarm_irq_enable(struct device *dev, unsigned int enabled)
2160ec7769aSVaibhav Jain {
2170ec7769aSVaibhav Jain struct rtc_wkalrm alarm = { .enabled = 0 };
2180ec7769aSVaibhav Jain
2190ec7769aSVaibhav Jain /*
2200ec7769aSVaibhav Jain * TPO is automatically enabled when opal_set_tpo_time() is called with
2210ec7769aSVaibhav Jain * non-zero rtc-time. We only handle disable case which needs to be
2220ec7769aSVaibhav Jain * explicitly told to opal.
2230ec7769aSVaibhav Jain */
2240ec7769aSVaibhav Jain return enabled ? 0 : opal_set_tpo_time(dev, &alarm);
2250ec7769aSVaibhav Jain }
2260ec7769aSVaibhav Jain
22750f97e91SAlexandre Belloni static const struct rtc_class_ops opal_rtc_ops = {
22816b1d26eSNeelesh Gupta .read_time = opal_get_rtc_time,
22916b1d26eSNeelesh Gupta .set_time = opal_set_rtc_time,
23050f97e91SAlexandre Belloni .read_alarm = opal_get_tpo_time,
23150f97e91SAlexandre Belloni .set_alarm = opal_set_tpo_time,
23250f97e91SAlexandre Belloni .alarm_irq_enable = opal_tpo_alarm_irq_enable,
23316b1d26eSNeelesh Gupta };
23416b1d26eSNeelesh Gupta
opal_rtc_probe(struct platform_device * pdev)23516b1d26eSNeelesh Gupta static int opal_rtc_probe(struct platform_device *pdev)
23616b1d26eSNeelesh Gupta {
23716b1d26eSNeelesh Gupta struct rtc_device *rtc;
23816b1d26eSNeelesh Gupta
2391bf3e6ccSAlexandre Belloni rtc = devm_rtc_allocate_device(&pdev->dev);
2401bf3e6ccSAlexandre Belloni if (IS_ERR(rtc))
2411bf3e6ccSAlexandre Belloni return PTR_ERR(rtc);
2421bf3e6ccSAlexandre Belloni
243347e40f0SSudeep Holla if (pdev->dev.of_node &&
244347e40f0SSudeep Holla (of_property_read_bool(pdev->dev.of_node, "wakeup-source") ||
24550f97e91SAlexandre Belloni of_property_read_bool(pdev->dev.of_node, "has-tpo")/* legacy */))
24616b1d26eSNeelesh Gupta device_set_wakeup_capable(&pdev->dev, true);
24750f97e91SAlexandre Belloni else
24850f97e91SAlexandre Belloni clear_bit(RTC_FEATURE_ALARM, rtc->features);
24916b1d26eSNeelesh Gupta
2501bf3e6ccSAlexandre Belloni rtc->ops = &opal_rtc_ops;
2511bf3e6ccSAlexandre Belloni rtc->range_min = RTC_TIMESTAMP_BEGIN_0000;
2521bf3e6ccSAlexandre Belloni rtc->range_max = RTC_TIMESTAMP_END_9999;
253*96599473SAlexandre Belloni clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features);
25416b1d26eSNeelesh Gupta
2551bf3e6ccSAlexandre Belloni return devm_rtc_register_device(rtc);
25616b1d26eSNeelesh Gupta }
25716b1d26eSNeelesh Gupta
25816b1d26eSNeelesh Gupta static const struct of_device_id opal_rtc_match[] = {
25916b1d26eSNeelesh Gupta {
26016b1d26eSNeelesh Gupta .compatible = "ibm,opal-rtc",
26116b1d26eSNeelesh Gupta },
26216b1d26eSNeelesh Gupta { }
26316b1d26eSNeelesh Gupta };
26416b1d26eSNeelesh Gupta MODULE_DEVICE_TABLE(of, opal_rtc_match);
26516b1d26eSNeelesh Gupta
26616b1d26eSNeelesh Gupta static const struct platform_device_id opal_rtc_driver_ids[] = {
26716b1d26eSNeelesh Gupta {
26816b1d26eSNeelesh Gupta .name = "opal-rtc",
26916b1d26eSNeelesh Gupta },
27016b1d26eSNeelesh Gupta { }
27116b1d26eSNeelesh Gupta };
27216b1d26eSNeelesh Gupta MODULE_DEVICE_TABLE(platform, opal_rtc_driver_ids);
27316b1d26eSNeelesh Gupta
27416b1d26eSNeelesh Gupta static struct platform_driver opal_rtc_driver = {
27516b1d26eSNeelesh Gupta .probe = opal_rtc_probe,
27616b1d26eSNeelesh Gupta .id_table = opal_rtc_driver_ids,
27716b1d26eSNeelesh Gupta .driver = {
27816b1d26eSNeelesh Gupta .name = DRVNAME,
27916b1d26eSNeelesh Gupta .of_match_table = opal_rtc_match,
28016b1d26eSNeelesh Gupta },
28116b1d26eSNeelesh Gupta };
28216b1d26eSNeelesh Gupta
opal_rtc_init(void)28316b1d26eSNeelesh Gupta static int __init opal_rtc_init(void)
28416b1d26eSNeelesh Gupta {
28516b1d26eSNeelesh Gupta if (!firmware_has_feature(FW_FEATURE_OPAL))
28616b1d26eSNeelesh Gupta return -ENODEV;
28716b1d26eSNeelesh Gupta
28816b1d26eSNeelesh Gupta return platform_driver_register(&opal_rtc_driver);
28916b1d26eSNeelesh Gupta }
29016b1d26eSNeelesh Gupta
opal_rtc_exit(void)29116b1d26eSNeelesh Gupta static void __exit opal_rtc_exit(void)
29216b1d26eSNeelesh Gupta {
29316b1d26eSNeelesh Gupta platform_driver_unregister(&opal_rtc_driver);
29416b1d26eSNeelesh Gupta }
29516b1d26eSNeelesh Gupta
29616b1d26eSNeelesh Gupta MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
29716b1d26eSNeelesh Gupta MODULE_DESCRIPTION("IBM OPAL RTC driver");
29816b1d26eSNeelesh Gupta MODULE_LICENSE("GPL");
29916b1d26eSNeelesh Gupta
30016b1d26eSNeelesh Gupta module_init(opal_rtc_init);
30116b1d26eSNeelesh Gupta module_exit(opal_rtc_exit);
302