Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /* rtc-sun4v.c: Hypervisor based RTC for SUN4V systems.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  * Author: David S. Miller
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/rtc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <asm/hypervisor.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) static unsigned long hypervisor_get_time(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	unsigned long ret, time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 	int retries = 10000;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) retry:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	ret = sun4v_tod_get(&time);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	if (ret == HV_EOK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 		return time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	if (ret == HV_EWOULDBLOCK) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 		if (--retries > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 			udelay(100);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 			goto retry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 		pr_warn("tod_get() timed out.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	pr_warn("tod_get() not supported.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) static int sun4v_read_time(struct device *dev, struct rtc_time *tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	rtc_time64_to_tm(hypervisor_get_time(), tm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) static int hypervisor_set_time(unsigned long secs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	unsigned long ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 	int retries = 10000;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) retry:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 	ret = sun4v_tod_set(secs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 	if (ret == HV_EOK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	if (ret == HV_EWOULDBLOCK) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 		if (--retries > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 			udelay(100);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 			goto retry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 		pr_warn("tod_set() timed out.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 		return -EAGAIN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 	pr_warn("tod_set() not supported.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	return -EOPNOTSUPP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) static int sun4v_set_time(struct device *dev, struct rtc_time *tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 	return hypervisor_set_time(rtc_tm_to_time64(tm));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) static const struct rtc_class_ops sun4v_rtc_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 	.read_time	= sun4v_read_time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 	.set_time	= sun4v_set_time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) static int __init sun4v_rtc_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 	struct rtc_device *rtc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) 	rtc = devm_rtc_allocate_device(&pdev->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 	if (IS_ERR(rtc))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) 		return PTR_ERR(rtc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) 	rtc->ops = &sun4v_rtc_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) 	rtc->range_max = U64_MAX;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) 	platform_set_drvdata(pdev, rtc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) 	return rtc_register_device(rtc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) static struct platform_driver sun4v_rtc_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) 	.driver		= {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) 		.name	= "rtc-sun4v",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) 	},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) builtin_platform_driver_probe(sun4v_rtc_driver, sun4v_rtc_probe);