/*
* Copyright (c) 2011 Zhao Zhang <zhzhl555@gmail.com>
*
* Derived from driver/rtc/rtc-au1xxx.c
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/rtc.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/types.h>
#include <linux/io.h>
#include <asm/mach-loongson1/loongson1.h>
#define LS1X_RTC_REG_OFFSET (LS1X_RTC_BASE + 0x20)
#define LS1X_RTC_REGS(x) \
((void __iomem *)KSEG1ADDR(LS1X_RTC_REG_OFFSET + (x)))
/*RTC programmable counters 0 and 1*/
#define SYS_COUNTER_CNTRL (LS1X_RTC_REGS(0x20))
#define SYS_CNTRL_ERS (1 << 23)
#define SYS_CNTRL_RTS (1 << 20)
#define SYS_CNTRL_RM2 (1 << 19)
#define SYS_CNTRL_RM1 (1 << 18)
#define SYS_CNTRL_RM0 (1 << 17)
#define SYS_CNTRL_RS (1 << 16)
#define SYS_CNTRL_BP (1 << 14)
#define SYS_CNTRL_REN (1 << 13)
#define SYS_CNTRL_BRT (1 << 12)
#define SYS_CNTRL_TEN (1 << 11)
#define SYS_CNTRL_BTT (1 << 10)
#define SYS_CNTRL_E0 (1 << 8)
#define SYS_CNTRL_ETS (1 << 7)
#define SYS_CNTRL_32S (1 << 5)
#define SYS_CNTRL_TTS (1 << 4)
#define SYS_CNTRL_TM2 (1 << 3)
#define SYS_CNTRL_TM1 (1 << 2)
#define SYS_CNTRL_TM0 (1 << 1)
#define SYS_CNTRL_TS (1 << 0)
/* Programmable Counter 0 Registers */
#define SYS_TOYTRIM (LS1X_RTC_REGS(0))
#define SYS_TOYWRITE0 (LS1X_RTC_REGS(4))
#define SYS_TOYWRITE1 (LS1X_RTC_REGS(8))
#define SYS_TOYREAD0 (LS1X_RTC_REGS(0xC))
#define SYS_TOYREAD1 (LS1X_RTC_REGS(0x10))
#define SYS_TOYMATCH0 (LS1X_RTC_REGS(0x14))
#define SYS_TOYMATCH1 (LS1X_RTC_REGS(0x18))
#define SYS_TOYMATCH2 (LS1X_RTC_REGS(0x1C))
/* Programmable Counter 1 Registers */
#define SYS_RTCTRIM (LS1X_RTC_REGS(0x40))
#define SYS_RTCWRITE0 (LS1X_RTC_REGS(0x44))
#define SYS_RTCREAD0 (LS1X_RTC_REGS(0x48))
#define SYS_RTCMATCH0 (LS1X_RTC_REGS(0x4C))
#define SYS_RTCMATCH1 (LS1X_RTC_REGS(0x50))
#define SYS_RTCMATCH2 (LS1X_RTC_REGS(0x54))
#define LS1X_SEC_OFFSET (4)
#define LS1X_MIN_OFFSET (10)
#define LS1X_HOUR_OFFSET (16)
#define LS1X_DAY_OFFSET (21)
#define LS1X_MONTH_OFFSET (26)
#define LS1X_SEC_MASK (0x3f)
#define LS1X_MIN_MASK (0x3f)
#define LS1X_HOUR_MASK (0x1f)
#define LS1X_DAY_MASK (0x1f)
#define LS1X_MONTH_MASK (0x3f)
#define LS1X_YEAR_MASK (0xffffffff)
#define ls1x_get_sec(t) (((t) >> LS1X_SEC_OFFSET) & LS1X_SEC_MASK)
#define ls1x_get_min(t) (((t) >> LS1X_MIN_OFFSET) & LS1X_MIN_MASK)
#define ls1x_get_hour(t) (((t) >> LS1X_HOUR_OFFSET) & LS1X_HOUR_MASK)
#define ls1x_get_day(t) (((t) >> LS1X_DAY_OFFSET) & LS1X_DAY_MASK)
#define ls1x_get_month(t) (((t) >> LS1X_MONTH_OFFSET) & LS1X_MONTH_MASK)
#define RTC_CNTR_OK (SYS_CNTRL_E0 | SYS_CNTRL_32S)
static int ls1x_rtc_read_time(struct device *dev, struct rtc_time *rtm)
{
unsigned long v, t;
v = readl(SYS_TOYREAD0);
t = readl(SYS_TOYREAD1);
memset(rtm, 0, sizeof(struct rtc_time));
t = mktime((t & LS1X_YEAR_MASK), ls1x_get_month(v),
ls1x_get_day(v), ls1x_get_hour(v),
ls1x_get_min(v), ls1x_get_sec(v));
rtc_time_to_tm(t, rtm);
return rtc_valid_tm(rtm);
}
static int ls1x_rtc_set_time(struct device *dev, struct rtc_time *rtm)
{
unsigned long v, t, c;
int ret = -ETIMEDOUT;
v = ((rtm->tm_mon + 1) << LS1X_MONTH_OFFSET)
| (rtm->tm_mday << LS1X_DAY_OFFSET)
| (rtm->tm_hour << LS1X_HOUR_OFFSET)
| (rtm->tm_min << LS1X_MIN_OFFSET)
| (rtm->tm_sec << LS1X_SEC_OFFSET);
writel(v, SYS_TOYWRITE0);
c = 0x10000;
/* add timeout check counter, for more safe */
while ((readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TS) && --c)
usleep_range(1000, 3000);
if (!c) {
dev_err(dev, "set time timeout!\n");
goto err;
}
t = rtm->tm_year + 1900;
writel(t, SYS_TOYWRITE1);
c = 0x10000;
while ((readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TS) && --c)
usleep_range(1000, 3000);
if (!c) {
dev_err(dev, "set time timeout!\n");
goto err;
}
return 0;
err:
return ret;
}
static struct rtc_class_ops ls1x_rtc_ops = {
.read_time = ls1x_rtc_read_time,
.set_time = ls1x_rtc_set_time,
};
static int ls1x_rtc_probe(struct platform_device *pdev)
{
struct rtc_device *rtcdev;
unsigned long v;
int ret;
v = readl(SYS_COUNTER_CNTRL);
if (!(v & RTC_CNTR_OK)) {
dev_err(&pdev->dev, "rtc counters not working\n");
ret = -ENODEV;
goto err;
}
ret = -ETIMEDOUT;
/* set to 1 HZ if needed */
if (readl(SYS_TOYTRIM) != 32767) {
v = 0x100000;
while ((readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TTS) && --v)
usleep_range(1000, 3000);
if (!v) {
dev_err(&pdev->dev, "time out\n");
goto err;
}
writel(32767, SYS_TOYTRIM);
}
/* this loop coundn't be endless */
while (readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TTS)
usleep_range(1000, 3000);
rtcdev = devm_rtc_device_register(&pdev->dev, "ls1x-rtc",
&ls1x_rtc_ops , THIS_MODULE);
if (IS_ERR(rtcdev)) {
ret = PTR_ERR(rtcdev);
goto err;
}
platform_set_drvdata(pdev, rtcdev);
return 0;
err:
return ret;
}
static int ls1x_rtc_remove(struct platform_device *pdev)
{
platform_set_drvdata(pdev, NULL);
return 0;
}
static struct platform_driver ls1x_rtc_driver = {
.driver = {
.name = "ls1x-rtc",
.owner = THIS_MODULE,
},
.remove = ls1x_rtc_remove,
.probe = ls1x_rtc_probe,
};
module_platform_driver(ls1x_rtc_driver);
MODULE_AUTHOR("zhao zhang <zhzhl555@gmail.com>");
MODULE_LICENSE("GPL");
