From 8ba706a95bb92c3b14b812f6d507890336d19136 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 1 Mar 2006 17:32:46 -0800 Subject: [SPARC64]: Add mini-RTC driver for Starfire and SUN4V. Signed-off-by: David S. Miller --- arch/sparc64/kernel/time.c | 279 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 279 insertions(+) diff --git a/arch/sparc64/kernel/time.c b/arch/sparc64/kernel/time.c index f6275adbc81..d50ebeae144 100644 --- a/arch/sparc64/kernel/time.c +++ b/arch/sparc64/kernel/time.c @@ -30,6 +30,8 @@ #include #include #include +#include +#include #include #include @@ -45,6 +47,7 @@ #include #include #include +#include DEFINE_SPINLOCK(mostek_lock); DEFINE_SPINLOCK(rtc_lock); @@ -702,6 +705,14 @@ static u32 starfire_get_time(void) return unix_tod; } +static int starfire_set_time(u32 val) +{ + /* Do nothing, time is set using the service processor + * console on this platform. + */ + return 0; +} + static u32 hypervisor_get_time(void) { register unsigned long func asm("%o5"); @@ -731,6 +742,33 @@ retry: return 0; } +static int hypervisor_set_time(u32 secs) +{ + register unsigned long func asm("%o5"); + register unsigned long arg0 asm("%o0"); + int retries = 10000; + +retry: + func = HV_FAST_TOD_SET; + arg0 = secs; + __asm__ __volatile__("ta %4" + : "=&r" (func), "=&r" (arg0) + : "0" (func), "1" (arg0), + "i" (HV_FAST_TRAP)); + if (arg0 == HV_EOK) + return 0; + if (arg0 == HV_EWOULDBLOCK) { + if (--retries > 0) { + udelay(100); + goto retry; + } + printk(KERN_WARNING "SUN4V: tod_set() timed out.\n"); + return -EAGAIN; + } + printk(KERN_WARNING "SUN4V: tod_set() not supported.\n"); + return -EOPNOTSUPP; +} + void __init clock_probe(void) { struct linux_prom_registers clk_reg[2]; @@ -1221,3 +1259,244 @@ static int set_rtc_mmss(unsigned long nowtime) return retval; } } + +#define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */ +static unsigned char mini_rtc_status; /* bitmapped status byte. */ + +/* months start at 0 now */ +static unsigned char days_in_mo[] = +{31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; + +#define FEBRUARY 2 +#define STARTOFTIME 1970 +#define SECDAY 86400L +#define SECYR (SECDAY * 365) +#define leapyear(year) ((year) % 4 == 0 && \ + ((year) % 100 != 0 || (year) % 400 == 0)) +#define days_in_year(a) (leapyear(a) ? 366 : 365) +#define days_in_month(a) (month_days[(a) - 1]) + +static int month_days[12] = { + 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 +}; + +/* + * This only works for the Gregorian calendar - i.e. after 1752 (in the UK) + */ +static void GregorianDay(struct rtc_time * tm) +{ + int leapsToDate; + int lastYear; + int day; + int MonthOffset[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 }; + + lastYear = tm->tm_year - 1; + + /* + * Number of leap corrections to apply up to end of last year + */ + leapsToDate = lastYear / 4 - lastYear / 100 + lastYear / 400; + + /* + * This year is a leap year if it is divisible by 4 except when it is + * divisible by 100 unless it is divisible by 400 + * + * e.g. 1904 was a leap year, 1900 was not, 1996 is, and 2000 was + */ + day = tm->tm_mon > 2 && leapyear(tm->tm_year); + + day += lastYear*365 + leapsToDate + MonthOffset[tm->tm_mon-1] + + tm->tm_mday; + + tm->tm_wday = day % 7; +} + +static void to_tm(int tim, struct rtc_time *tm) +{ + register int i; + register long hms, day; + + day = tim / SECDAY; + hms = tim % SECDAY; + + /* Hours, minutes, seconds are easy */ + tm->tm_hour = hms / 3600; + tm->tm_min = (hms % 3600) / 60; + tm->tm_sec = (hms % 3600) % 60; + + /* Number of years in days */ + for (i = STARTOFTIME; day >= days_in_year(i); i++) + day -= days_in_year(i); + tm->tm_year = i; + + /* Number of months in days left */ + if (leapyear(tm->tm_year)) + days_in_month(FEBRUARY) = 29; + for (i = 1; day >= days_in_month(i); i++) + day -= days_in_month(i); + days_in_month(FEBRUARY) = 28; + tm->tm_mon = i; + + /* Days are what is left over (+1) from all that. */ + tm->tm_mday = day + 1; + + /* + * Determine the day of week + */ + GregorianDay(tm); +} + +/* Both Starfire and SUN4V give us seconds since Jan 1st, 1970, + * aka Unix time. So we have to convert to/from rtc_time. + */ +static inline void mini_get_rtc_time(struct rtc_time *time) +{ + unsigned long flags; + u32 seconds; + + spin_lock_irqsave(&rtc_lock, flags); + seconds = 0; + if (this_is_starfire) + seconds = starfire_get_time(); + else if (tlb_type == hypervisor) + seconds = hypervisor_get_time(); + spin_unlock_irqrestore(&rtc_lock, flags); + + to_tm(seconds, time); +} + +static inline int mini_set_rtc_time(struct rtc_time *time) +{ + u32 seconds = mktime(time->tm_year + 1900, time->tm_mon + 1, + time->tm_mday, time->tm_hour, + time->tm_min, time->tm_sec); + unsigned long flags; + int err; + + spin_lock_irqsave(&rtc_lock, flags); + err = -ENODEV; + if (this_is_starfire) + err = starfire_set_time(seconds); + else if (tlb_type == hypervisor) + err = hypervisor_set_time(seconds); + spin_unlock_irqrestore(&rtc_lock, flags); + + return err; +} + +static int mini_rtc_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg) +{ + struct rtc_time wtime; + void __user *argp = (void __user *)arg; + + switch (cmd) { + + case RTC_PLL_GET: + return -EINVAL; + + case RTC_PLL_SET: + return -EINVAL; + + case RTC_UIE_OFF: /* disable ints from RTC updates. */ + return 0; + + case RTC_UIE_ON: /* enable ints for RTC updates. */ + return -EINVAL; + + case RTC_RD_TIME: /* Read the time/date from RTC */ + /* this doesn't get week-day, who cares */ + memset(&wtime, 0, sizeof(wtime)); + mini_get_rtc_time(&wtime); + + return copy_to_user(argp, &wtime, sizeof(wtime)) ? -EFAULT : 0; + + case RTC_SET_TIME: /* Set the RTC */ + { + int year; + unsigned char leap_yr; + + if (!capable(CAP_SYS_TIME)) + return -EACCES; + + if (copy_from_user(&wtime, argp, sizeof(wtime))) + return -EFAULT; + + year = wtime.tm_year + 1900; + leap_yr = ((!(year % 4) && (year % 100)) || + !(year % 400)); + + if ((wtime.tm_mon < 0 || wtime.tm_mon > 11) || (wtime.tm_mday < 1)) + return -EINVAL; + + if (wtime.tm_mday < 0 || wtime.tm_mday > + (days_in_mo[wtime.tm_mon] + ((wtime.tm_mon == 1) && leap_yr))) + return -EINVAL; + + if (wtime.tm_hour < 0 || wtime.tm_hour >= 24 || + wtime.tm_min < 0 || wtime.tm_min >= 60 || + wtime.tm_sec < 0 || wtime.tm_sec >= 60) + return -EINVAL; + + return mini_set_rtc_time(&wtime); + } + } + + return -EINVAL; +} + +static int mini_rtc_open(struct inode *inode, struct file *file) +{ + if (mini_rtc_status & RTC_IS_OPEN) + return -EBUSY; + + mini_rtc_status |= RTC_IS_OPEN; + + return 0; +} + +static int mini_rtc_release(struct inode *inode, struct file *file) +{ + mini_rtc_status &= ~RTC_IS_OPEN; + return 0; +} + + +static struct file_operations mini_rtc_fops = { + .owner = THIS_MODULE, + .ioctl = mini_rtc_ioctl, + .open = mini_rtc_open, + .release = mini_rtc_release, +}; + +static struct miscdevice rtc_mini_dev = +{ + .minor = RTC_MINOR, + .name = "rtc", + .fops = &mini_rtc_fops, +}; + +static int __init rtc_mini_init(void) +{ + int retval; + + if (tlb_type != hypervisor && !this_is_starfire) + return -ENODEV; + + printk(KERN_INFO "Mini RTC Driver\n"); + + retval = misc_register(&rtc_mini_dev); + if (retval < 0) + return retval; + + return 0; +} + +static void __exit rtc_mini_exit(void) +{ + misc_deregister(&rtc_mini_dev); +} + + +module_init(rtc_mini_init); +module_exit(rtc_mini_exit); -- cgit v1.2.3