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-rw-r--r--arch/x86/kernel/Makefile_322
-rw-r--r--arch/x86/kernel/rtc.c166
-rw-r--r--arch/x86/kernel/time_32.c105
3 files changed, 171 insertions, 102 deletions
diff --git a/arch/x86/kernel/Makefile_32 b/arch/x86/kernel/Makefile_32
index 31ff982bc26..eb2da53578d 100644
--- a/arch/x86/kernel/Makefile_32
+++ b/arch/x86/kernel/Makefile_32
@@ -8,7 +8,7 @@ CPPFLAGS_vmlinux.lds += -Ui386
obj-y := process_32.o signal_32.o entry_32.o traps_32.o irq_32.o \
ptrace_32.o time_32.o ioport_32.o ldt.o setup_32.o i8259_32.o sys_i386_32.o \
pci-dma_32.o i386_ksyms_32.o i387_32.o bootflag.o e820_32.o\
- quirks.o i8237.o topology.o alternative.o i8253.o tsc_32.o io_delay.o
+ quirks.o i8237.o topology.o alternative.o i8253.o tsc_32.o io_delay.o rtc.o
obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-y += cpu/
diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c
new file mode 100644
index 00000000000..45bf54d9f4c
--- /dev/null
+++ b/arch/x86/kernel/rtc.c
@@ -0,0 +1,166 @@
+/*
+ * RTC related functions
+ */
+#include <linux/bcd.h>
+#include <linux/mc146818rtc.h>
+
+#include <asm/time.h>
+
+/*
+ * In order to set the CMOS clock precisely, set_rtc_mmss has to be
+ * called 500 ms after the second nowtime has started, because when
+ * 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 retval = 0;
+ int real_seconds, real_minutes, cmos_minutes;
+ unsigned char save_control, save_freq_select;
+
+ save_control = CMOS_READ(RTC_CONTROL); /* tell the clock it's being set */
+ CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL);
+
+ save_freq_select = CMOS_READ(RTC_FREQ_SELECT); /* stop and reset prescaler */
+ 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;
+ if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
+ real_minutes += 30; /* correct for half hour time zone */
+ 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);
+ } else {
+ printk(KERN_WARNING
+ "set_rtc_mmss: can't update from %d to %d\n",
+ cmos_minutes, real_minutes);
+ retval = -1;
+ }
+
+ /* 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)
+{
+ unsigned int year, mon, day, hour, min, sec;
+
+ do {
+ sec = CMOS_READ(RTC_SECONDS);
+ min = CMOS_READ(RTC_MINUTES);
+ hour = CMOS_READ(RTC_HOURS);
+ day = CMOS_READ(RTC_DAY_OF_MONTH);
+ mon = CMOS_READ(RTC_MONTH);
+ year = CMOS_READ(RTC_YEAR);
+ } while (sec != CMOS_READ(RTC_SECONDS));
+
+ if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
+ BCD_TO_BIN(sec);
+ BCD_TO_BIN(min);
+ BCD_TO_BIN(hour);
+ BCD_TO_BIN(day);
+ BCD_TO_BIN(mon);
+ BCD_TO_BIN(year);
+ }
+
+ year += 1900;
+ if (year < 1970)
+ year += 100;
+
+ return mktime(year, mon, day, hour, min, sec);
+}
+
+DEFINE_SPINLOCK(rtc_lock);
+EXPORT_SYMBOL(rtc_lock);
+
+/*
+ * 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;
+EXPORT_SYMBOL(cmos_lock);
+
+/* Routines for accessing the CMOS RAM/RTC. */
+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));
+ lock_cmos_suffix(addr);
+ return val;
+}
+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));
+ lock_cmos_suffix(addr);
+}
+EXPORT_SYMBOL(rtc_cmos_write);
+
+static int set_rtc_mmss(unsigned long nowtime)
+{
+ int retval;
+ unsigned long flags;
+
+ /* gets recalled with irq locally disabled */
+ /* XXX - does irqsave resolve this? -johnstul */
+ spin_lock_irqsave(&rtc_lock, flags);
+ retval = set_wallclock(nowtime);
+ spin_unlock_irqrestore(&rtc_lock, flags);
+
+ return retval;
+}
+
+/* not static: needed by APM */
+unsigned long read_persistent_clock(void)
+{
+ unsigned long retval;
+ unsigned long flags;
+
+ spin_lock_irqsave(&rtc_lock, flags);
+ retval = get_wallclock();
+ spin_unlock_irqrestore(&rtc_lock, flags);
+
+ return retval;
+}
+
+int update_persistent_clock(struct timespec now)
+{
+ return set_rtc_mmss(now.tv_sec);
+}
diff --git a/arch/x86/kernel/time_32.c b/arch/x86/kernel/time_32.c
index 8a322c96bc2..e9ead762abe 100644
--- a/arch/x86/kernel/time_32.c
+++ b/arch/x86/kernel/time_32.c
@@ -28,98 +28,21 @@
* serialize accesses to xtime/lost_ticks).
*/
-#include <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/kernel.h>
-#include <linux/param.h>
-#include <linux/string.h>
-#include <linux/mm.h>
+#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/time.h>
-#include <linux/delay.h>
-#include <linux/init.h>
-#include <linux/smp.h>
-#include <linux/module.h>
-#include <linux/sysdev.h>
-#include <linux/bcd.h>
-#include <linux/efi.h>
#include <linux/mca.h>
-#include <asm/io.h>
-#include <asm/smp.h>
-#include <asm/irq.h>
-#include <asm/msr.h>
-#include <asm/delay.h>
-#include <asm/mpspec.h>
-#include <asm/uaccess.h>
-#include <asm/processor.h>
-#include <asm/timer.h>
-#include <asm/time.h>
-
-#include "mach_time.h"
-
-#include <linux/timex.h>
-
-#include <asm/hpet.h>
-
#include <asm/arch_hooks.h>
+#include <asm/hpet.h>
+#include <asm/time.h>
#include "io_ports.h"
-
-#include <asm/i8259.h>
-
#include "do_timer.h"
unsigned int cpu_khz; /* Detected as we calibrate the TSC */
EXPORT_SYMBOL(cpu_khz);
-DEFINE_SPINLOCK(rtc_lock);
-EXPORT_SYMBOL(rtc_lock);
-
-/*
- * 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;
-EXPORT_SYMBOL(cmos_lock);
-
-/* Routines for accessing the CMOS RAM/RTC. */
-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));
- lock_cmos_suffix(addr);
- return val;
-}
-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));
- lock_cmos_suffix(addr);
-}
-EXPORT_SYMBOL(rtc_cmos_write);
-
-static int set_rtc_mmss(unsigned long nowtime)
-{
- int retval;
- unsigned long flags;
-
- /* gets recalled with irq locally disabled */
- /* XXX - does irqsave resolve this? -johnstul */
- spin_lock_irqsave(&rtc_lock, flags);
- retval = set_wallclock(nowtime);
- spin_unlock_irqrestore(&rtc_lock, flags);
-
- return retval;
-}
-
-
int timer_ack;
unsigned long profile_pc(struct pt_regs *regs)
@@ -137,7 +60,7 @@ unsigned long profile_pc(struct pt_regs *regs)
/* Return address is either directly at stack pointer
or above a saved eflags. Eflags has bits 22-31 zero,
kernel addresses don't. */
- if (sp[0] >> 22)
+ if (sp[0] >> 22)
return sp[0];
if (sp[1] >> 22)
return sp[1];
@@ -193,26 +116,6 @@ irqreturn_t timer_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
-/* not static: needed by APM */
-unsigned long read_persistent_clock(void)
-{
- unsigned long retval;
- unsigned long flags;
-
- spin_lock_irqsave(&rtc_lock, flags);
-
- retval = get_wallclock();
-
- spin_unlock_irqrestore(&rtc_lock, flags);
-
- return retval;
-}
-
-int update_persistent_clock(struct timespec now)
-{
- return set_rtc_mmss(now.tv_sec);
-}
-
extern void (*late_time_init)(void);
/* Duplicate of time_init() below, with hpet_enable part added */
void __init hpet_time_init(void)
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-25 06:03:13 +0000