diff options
Diffstat (limited to 'arch/x86/kernel/rtc.c')
| -rw-r--r-- | arch/x86/kernel/rtc.c | 121 |
1 files changed, 42 insertions, 79 deletions
diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c index 1cfbbfc3ae2..ca9622a25e9 100644 --- a/arch/x86/kernel/rtc.c +++ b/arch/x86/kernel/rtc.c @@ -5,11 +5,15 @@ #include <linux/mc146818rtc.h> #include <linux/acpi.h> #include <linux/bcd.h> +#include <linux/export.h> #include <linux/pnp.h> +#include <linux/of.h> #include <asm/vsyscall.h> #include <asm/x86_init.h> #include <asm/time.h> +#include <asm/intel-mid.h> +#include <asm/rtc.h> #ifdef CONFIG_X86_32 /* @@ -33,71 +37,34 @@ EXPORT_SYMBOL(rtc_lock); * nowtime is written into the registers of the CMOS clock, it will * jump to the next second precisely 500 ms later. Check the Motorola * MC146818A or Dallas DS12887 data sheet for details. - * - * BUG: This routine does not handle hour overflow properly; it just - * sets the minutes. Usually you'll only notice that after reboot! */ -int mach_set_rtc_mmss(unsigned long nowtime) +int mach_set_rtc_mmss(const struct timespec *now) { - int real_seconds, real_minutes, cmos_minutes; - unsigned char save_control, save_freq_select; + unsigned long nowtime = now->tv_sec; + struct rtc_time tm; int retval = 0; - /* tell the clock it's being set */ - save_control = CMOS_READ(RTC_CONTROL); - CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL); - - /* stop and reset prescaler */ - save_freq_select = CMOS_READ(RTC_FREQ_SELECT); - CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT); - - cmos_minutes = CMOS_READ(RTC_MINUTES); - if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) - cmos_minutes = bcd2bin(cmos_minutes); - - /* - * since we're only adjusting minutes and seconds, - * don't interfere with hour overflow. This avoids - * messing with unknown time zones but requires your - * RTC not to be off by more than 15 minutes - */ - real_seconds = nowtime % 60; - real_minutes = nowtime / 60; - /* correct for half hour time zone */ - if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1) - real_minutes += 30; - real_minutes %= 60; - - if (abs(real_minutes - cmos_minutes) < 30) { - if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { - real_seconds = bin2bcd(real_seconds); - real_minutes = bin2bcd(real_minutes); - } - CMOS_WRITE(real_seconds, RTC_SECONDS); - CMOS_WRITE(real_minutes, RTC_MINUTES); + rtc_time_to_tm(nowtime, &tm); + if (!rtc_valid_tm(&tm)) { + retval = set_rtc_time(&tm); + if (retval) + printk(KERN_ERR "%s: RTC write failed with error %d\n", + __FUNCTION__, retval); } else { - printk(KERN_WARNING - "set_rtc_mmss: can't update from %d to %d\n", - cmos_minutes, real_minutes); - retval = -1; + printk(KERN_ERR + "%s: Invalid RTC value: write of %lx to RTC failed\n", + __FUNCTION__, nowtime); + retval = -EINVAL; } - - /* The following flags have to be released exactly in this order, - * otherwise the DS12887 (popular MC146818A clone with integrated - * battery and quartz) will not reset the oscillator and will not - * update precisely 500 ms later. You won't find this mentioned in - * the Dallas Semiconductor data sheets, but who believes data - * sheets anyway ... -- Markus Kuhn - */ - CMOS_WRITE(save_control, RTC_CONTROL); - CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT); - return retval; } -unsigned long mach_get_cmos_time(void) +void mach_get_cmos_time(struct timespec *now) { unsigned int status, year, mon, day, hour, min, sec, century = 0; + unsigned long flags; + + spin_lock_irqsave(&rtc_lock, flags); /* * If UIP is clear, then we have >= 244 microseconds before @@ -124,6 +91,8 @@ unsigned long mach_get_cmos_time(void) status = CMOS_READ(RTC_CONTROL); WARN_ON_ONCE(RTC_ALWAYS_BCD && (status & RTC_DM_BINARY)); + spin_unlock_irqrestore(&rtc_lock, flags); + if (RTC_ALWAYS_BCD || !(status & RTC_DM_BINARY)) { sec = bcd2bin(sec); min = bcd2bin(min); @@ -136,11 +105,11 @@ unsigned long mach_get_cmos_time(void) if (century) { century = bcd2bin(century); year += century * 100; - printk(KERN_INFO "Extended CMOS year: %d\n", century * 100); } else year += CMOS_YEARS_OFFS; - return mktime(year, mon, day, hour, min, sec); + now->tv_sec = mktime(year, mon, day, hour, min, sec); + now->tv_nsec = 0; } /* Routines for accessing the CMOS RAM/RTC. */ @@ -168,34 +137,14 @@ EXPORT_SYMBOL(rtc_cmos_write); int update_persistent_clock(struct timespec now) { - unsigned long flags; - int retval; - - spin_lock_irqsave(&rtc_lock, flags); - retval = x86_platform.set_wallclock(now.tv_sec); - spin_unlock_irqrestore(&rtc_lock, flags); - - return retval; + return x86_platform.set_wallclock(&now); } /* not static: needed by APM */ void read_persistent_clock(struct timespec *ts) { - unsigned long retval, flags; - - spin_lock_irqsave(&rtc_lock, flags); - retval = x86_platform.get_wallclock(); - spin_unlock_irqrestore(&rtc_lock, flags); - - ts->tv_sec = retval; - ts->tv_nsec = 0; -} - -unsigned long long native_read_tsc(void) -{ - return __native_read_tsc(); + x86_platform.get_wallclock(ts); } -EXPORT_SYMBOL(native_read_tsc); static struct resource rtc_resources[] = { @@ -221,7 +170,7 @@ static struct platform_device rtc_device = { static __init int add_rtc_cmos(void) { #ifdef CONFIG_PNP - static const char *ids[] __initconst = + static const char * const const ids[] __initconst = { "PNP0b00", "PNP0b01", "PNP0b02", }; struct pnp_dev *dev; struct pnp_id *id; @@ -236,6 +185,20 @@ static __init int add_rtc_cmos(void) } } #endif + if (of_have_populated_dt()) + return 0; + + /* Intel MID platforms don't have ioport rtc */ + if (intel_mid_identify_cpu()) + return -ENODEV; + +#ifdef CONFIG_ACPI + if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_CMOS_RTC) { + /* This warning can likely go away again in a year or two. */ + pr_info("ACPI: not registering RTC platform device\n"); + return -ENODEV; + } +#endif platform_device_register(&rtc_device); dev_info(&rtc_device.dev, |