diff options
Diffstat (limited to 'sys/arch/i386/isa/clock.c')
| -rw-r--r-- | sys/arch/i386/isa/clock.c | 70 |
1 files changed, 58 insertions, 12 deletions
diff --git a/sys/arch/i386/isa/clock.c b/sys/arch/i386/isa/clock.c index aed8f785522..0d1a0e7440f 100644 --- a/sys/arch/i386/isa/clock.c +++ b/sys/arch/i386/isa/clock.c @@ -1,4 +1,4 @@ -/* $OpenBSD: clock.c,v 1.21 2000/01/29 04:27:48 mickey Exp $ */ +/* $OpenBSD: clock.c,v 1.22 2001/02/13 17:19:12 ho Exp $ */ /* $NetBSD: clock.c,v 1.39 1996/05/12 23:11:54 mycroft Exp $ */ /*- @@ -89,11 +89,13 @@ WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. /* * Primitive clock interrupt routines. */ +#include <sys/types.h> #include <sys/param.h> #include <sys/systm.h> #include <sys/time.h> #include <sys/kernel.h> #include <sys/device.h> +#include <sys/timeout.h> #include <machine/cpu.h> #include <machine/intr.h> @@ -141,6 +143,7 @@ void rtcput __P((mc_todregs *)); int hexdectodec __P((int)); int dectohexdec __P((int)); int rtcintr __P((void *)); +void rtcdrain __P((void *)); __inline u_int mc146818_read __P((void *, u_int)); __inline void mc146818_write __P((void *, u_int, u_int)); @@ -157,9 +160,16 @@ mc146818_read(sc, reg) void *sc; /* XXX use it? */ u_int reg; { + int s; + u_char v; + s = splhigh(); outb(IO_RTC, reg); - return (inb(IO_RTC+1)); + DELAY(1); + v = inb(IO_RTC+1); + DELAY(1); + splx(s); + return (v); } __inline void @@ -167,9 +177,14 @@ mc146818_write(sc, reg, datum) void *sc; /* XXX use it? */ u_int reg, datum; { + int s; + s = splhigh(); outb(IO_RTC, reg); + DELAY(1); outb(IO_RTC+1, datum); + DELAY(1); + splx(s); } void @@ -188,6 +203,21 @@ startrtclock() } void +rtcdrain(void *v) +{ + struct timeout *to = (struct timeout *)v; + + timeout_del(to); + + /* + * Drain any un-acknowledged RTC interrupts. + * See comment in cpu_initclocks(). + */ + while (mc146818_read(NULL, MC_REGC) & MC_REGC_PF) + ; /* Nothing. */ +} + +void initrtclock() { /* initialize 8253 clock */ @@ -205,7 +235,7 @@ clockintr(arg) struct clockframe *frame = arg; /* not strictly necessary */ hardclock(frame); - return 1; + return (1); } int @@ -213,14 +243,17 @@ rtcintr(arg) void *arg; { struct clockframe *frame = arg; /* not strictly neccecary */ - u_int stat; + u_int stat = 0; - stat = mc146818_read(NULL, MC_REGC); - if (stat & MC_REGC_PF) { + /* + * If rtcintr is 'late', next intr may happen immediately. + * Get them all. (Also, see comment in cpu_initclocks().) + */ + while (mc146818_read(NULL, MC_REGC) & MC_REGC_PF) { statclock(frame); - return 1; + stat = 1; } - return 0; + return (stat); } int @@ -381,6 +414,7 @@ calibrate_cyclecounter() void cpu_initclocks() { + static struct timeout rtcdrain_timeout; stathz = 128; profhz = 1024; @@ -395,6 +429,18 @@ cpu_initclocks() mc146818_write(NULL, MC_REGA, MC_BASE_32_KHz | MC_RATE_128_Hz); mc146818_write(NULL, MC_REGB, MC_REGB_24HR | MC_REGB_PIE); + + /* + * On a number of i386 systems, the rtc will fail to start when booting + * the system. This is due to us missing to acknowledge an interrupt + * during early stages of the boot process. If we do not acknowledge + * the interrupt, the rtc clock will not generate further interrupts. + * To solve this, once interrupts are enabled, use a timeout (once) + * to drain any un-acknowledged rtc interrupt(s). + */ + + timeout_set(&rtcdrain_timeout, rtcdrain, (void *)&rtcdrain_timeout); + timeout_add(&rtcdrain_timeout, 1); } int @@ -436,8 +482,8 @@ static int timeset; * check whether the CMOS layout is "standard"-like (ie, not PS/2-like), * to be called at splclock() */ -static int cmoscheck __P((void)); -static int +int cmoscheck __P((void)); +int cmoscheck() { int i; @@ -463,8 +509,8 @@ int rtc_update_century = 0; * into full width. * Being here, deal with the CMOS century byte. */ -static int clock_expandyear __P((int)); -static int +int clock_expandyear __P((int)); +int clock_expandyear(clockyear) int clockyear; { |