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Diffstat (limited to 'arch/x86/kernel/rtc.c')
-rw-r--r--arch/x86/kernel/rtc.c225
1 files changed, 115 insertions, 110 deletions
diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c
index eb9b1a198f5..ca9622a25e9 100644
--- a/arch/x86/kernel/rtc.c
+++ b/arch/x86/kernel/rtc.c
@@ -1,29 +1,32 @@
/*
* RTC related functions
*/
+#include <linux/platform_device.h>
+#include <linux/mc146818rtc.h>
#include <linux/acpi.h>
#include <linux/bcd.h>
-#include <linux/mc146818rtc.h>
+#include <linux/export.h>
+#include <linux/pnp.h>
+#include <linux/of.h>
-#include <asm/time.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
-# define CMOS_YEARS_OFFS 1900
/*
* This is a special lock that is owned by the CPU and holds the index
* register we are working with. It is required for NMI access to the
* CMOS/RTC registers. See include/asm-i386/mc146818rtc.h for details.
*/
-volatile unsigned long cmos_lock = 0;
+volatile unsigned long cmos_lock;
EXPORT_SYMBOL(cmos_lock);
-#else
-/*
- * x86-64 systems only exists since 2002.
- * This will work up to Dec 31, 2100
- */
-# define CMOS_YEARS_OFFS 2000
-#endif
+#endif /* CONFIG_X86_32 */
+
+/* For two digit years assume time is always after that */
+#define CMOS_YEARS_OFFS 2000
DEFINE_SPINLOCK(rtc_lock);
EXPORT_SYMBOL(rtc_lock);
@@ -34,71 +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)
{
+ unsigned long nowtime = now->tv_sec;
+ struct rtc_time tm;
int retval = 0;
- int real_seconds, real_minutes, cmos_minutes;
- unsigned char save_control, save_freq_select;
-
- /* 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)
- BCD_TO_BIN(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) {
- BIN_TO_BCD(real_seconds);
- BIN_TO_BCD(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 year, mon, day, hour, min, sec, century = 0;
+ 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
@@ -116,33 +82,34 @@ unsigned long mach_get_cmos_time(void)
mon = CMOS_READ(RTC_MONTH);
year = CMOS_READ(RTC_YEAR);
-#if defined(CONFIG_ACPI) && defined(CONFIG_X86_64)
- /* CHECKME: Is this really 64bit only ??? */
+#ifdef CONFIG_ACPI
if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
acpi_gbl_FADT.century)
century = CMOS_READ(acpi_gbl_FADT.century);
#endif
- if (RTC_ALWAYS_BCD || !(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY)) {
- BCD_TO_BIN(sec);
- BCD_TO_BIN(min);
- BCD_TO_BIN(hour);
- BCD_TO_BIN(day);
- BCD_TO_BIN(mon);
- BCD_TO_BIN(year);
+ 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);
+ hour = bcd2bin(hour);
+ day = bcd2bin(day);
+ mon = bcd2bin(mon);
+ year = bcd2bin(year);
}
if (century) {
- BCD_TO_BIN(century);
+ century = bcd2bin(century);
year += century * 100;
- printk(KERN_INFO "Extended CMOS year: %d\n", century * 100);
- } else {
+ } else
year += CMOS_YEARS_OFFS;
- if (year < 1970)
- year += 100;
- }
- 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. */
@@ -151,9 +118,10 @@ unsigned char rtc_cmos_read(unsigned char addr)
unsigned char val;
lock_cmos_prefix(addr);
- outb_p(addr, RTC_PORT(0));
- val = inb_p(RTC_PORT(1));
+ outb(addr, RTC_PORT(0));
+ val = inb(RTC_PORT(1));
lock_cmos_suffix(addr);
+
return val;
}
EXPORT_SYMBOL(rtc_cmos_read);
@@ -161,44 +129,81 @@ EXPORT_SYMBOL(rtc_cmos_read);
void rtc_cmos_write(unsigned char val, unsigned char addr)
{
lock_cmos_prefix(addr);
- outb_p(addr, RTC_PORT(0));
- outb_p(val, RTC_PORT(1));
+ outb(addr, RTC_PORT(0));
+ outb(val, RTC_PORT(1));
lock_cmos_suffix(addr);
}
EXPORT_SYMBOL(rtc_cmos_write);
-static int set_rtc_mmss(unsigned long nowtime)
+int update_persistent_clock(struct timespec now)
{
- int retval;
- unsigned long flags;
-
- spin_lock_irqsave(&rtc_lock, flags);
- retval = set_wallclock(nowtime);
- spin_unlock_irqrestore(&rtc_lock, flags);
-
- return retval;
+ return x86_platform.set_wallclock(&now);
}
/* not static: needed by APM */
-unsigned long read_persistent_clock(void)
+void read_persistent_clock(struct timespec *ts)
{
- unsigned long retval, flags;
+ x86_platform.get_wallclock(ts);
+}
- spin_lock_irqsave(&rtc_lock, flags);
- retval = get_wallclock();
- spin_unlock_irqrestore(&rtc_lock, flags);
- return retval;
-}
+static struct resource rtc_resources[] = {
+ [0] = {
+ .start = RTC_PORT(0),
+ .end = RTC_PORT(1),
+ .flags = IORESOURCE_IO,
+ },
+ [1] = {
+ .start = RTC_IRQ,
+ .end = RTC_IRQ,
+ .flags = IORESOURCE_IRQ,
+ }
+};
-int update_persistent_clock(struct timespec now)
-{
- return set_rtc_mmss(now.tv_sec);
-}
+static struct platform_device rtc_device = {
+ .name = "rtc_cmos",
+ .id = -1,
+ .resource = rtc_resources,
+ .num_resources = ARRAY_SIZE(rtc_resources),
+};
-unsigned long long native_read_tsc(void)
+static __init int add_rtc_cmos(void)
{
- return __native_read_tsc();
-}
-EXPORT_SYMBOL(native_read_tsc);
+#ifdef CONFIG_PNP
+ static const char * const const ids[] __initconst =
+ { "PNP0b00", "PNP0b01", "PNP0b02", };
+ struct pnp_dev *dev;
+ struct pnp_id *id;
+ int i;
+
+ pnp_for_each_dev(dev) {
+ for (id = dev->id; id; id = id->next) {
+ for (i = 0; i < ARRAY_SIZE(ids); i++) {
+ if (compare_pnp_id(id, ids[i]) != 0)
+ return 0;
+ }
+ }
+ }
+#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,
+ "registered platform RTC device (no PNP device found)\n");
+ return 0;
+}
+device_initcall(add_rtc_cmos);
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