[src/trunk]: src/sys/arch/arm/s3c2xx0 + use system's real PCLK frequency for ...

[bsh <bsh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/d78d43a335ee
branches:  trunk
changeset: 547102:d78d43a335ee
user:      bsh <bsh%NetBSD.org@localhost>
date:      Tue May 13 08:07:39 2003 +0000

description:
+ use system's real PCLK frequency for calculation, instead of a compile
  time constant.

+ make delay() more accurate.

diffstat:

 sys/arch/arm/s3c2xx0/s3c2800_clk.c |  68 ++++++++++++++++++++++---------------
 1 files changed, 40 insertions(+), 28 deletions(-)

diffs (176 lines):

diff -r d5c841d98d56 -r d78d43a335ee sys/arch/arm/s3c2xx0/s3c2800_clk.c
--- a/sys/arch/arm/s3c2xx0/s3c2800_clk.c        Tue May 13 07:17:46 2003 +0000
+++ b/sys/arch/arm/s3c2xx0/s3c2800_clk.c        Tue May 13 08:07:39 2003 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: s3c2800_clk.c,v 1.3 2003/05/12 07:49:11 bsh Exp $ */
+/* $NetBSD: s3c2800_clk.c,v 1.4 2003/05/13 08:07:39 bsh Exp $ */
 
 /*
  * Copyright (c) 2002 Fujitsu Component Limited
@@ -49,23 +49,24 @@
 #include <arm/s3c2xx0/s3c2800var.h>
 
 
-#ifndef PCLK
-#define PCLK  (50*1000*1000)
-#endif
-
 #ifndef STATHZ
 #define STATHZ 64
 #endif
 
-#define TIMER_FREQUENCY (PCLK/4)       /* divider=1/4 */
+#define TIMER_FREQUENCY(pclk) ((pclk)/32) /* divider=1/32 */
 
 #define TIMER_RELOAD_VAL  1000
 #define COUNTS_PER_USEC   100
 
 static unsigned int timer0_reload_value;
 static unsigned int timer0_prescaler;
+static unsigned int timer0_mseccount;
 
-#define counter_to_usec(c)     (((c)*timer0_prescaler*1000)/(TIMER_FREQUENCY/1000))
+#define usec_to_counter(t)     \
+       ((timer0_mseccount*(t))/1000)
+
+#define counter_to_usec(c,pclk)        \
+       (((c)*timer0_prescaler*1000)/(TIMER_FREQUENCY(pclk)/1000))
 
 /*
  * microtime:
@@ -79,6 +80,7 @@
        struct s3c2800_softc *sc = (struct s3c2800_softc *) s3c2xx0_softc;
        int save, int_pend0, int_pend1, count, delta;
        static struct timeval last;
+       int pclk = s3c2xx0_softc->sc_pclk;
 
        if( timer0_reload_value == 0 ){
                /* not initialized yet */
@@ -144,7 +146,7 @@
 #endif
        }
 
-       tvp->tv_usec += counter_to_usec(delta);
+       tvp->tv_usec += counter_to_usec(delta, pclk);
 
        /* Make sure microseconds doesn't overflow. */
        tvp->tv_sec += tvp->tv_usec / 1000000;
@@ -200,6 +202,7 @@
 {
        struct s3c2800_softc *sc = (struct s3c2800_softc *) s3c2xx0_softc;
        int v0, v1, delta;
+       u_int ucnt;
 
        if ( timer0_reload_value == 0 ){
                /* not initialized yet */
@@ -215,26 +218,29 @@
        /* read down counter */
        v0 = read_timer(sc);
 
-       for(;;){
+       ucnt = usec_to_counter(n);
+
+       while( ucnt > 0 ) {
                v1 = read_timer(sc);
                delta = v0 - v1;
-               if ( delta < 0 ){
+               if ( delta < 0 )
                        delta += timer0_reload_value;
-               }
 #ifdef DEBUG
                if (delta < 0 || delta > timer0_reload_value)
                        panic("wrong value from timer counter");
 #endif
 
-               delta = counter_to_usec(delta);
-
-               if (delta >= n )
-                       return;
-               n -= delta;
-               v0 = v1;
+               if((u_int)delta < ucnt){
+                       ucnt -= (u_int)delta;
+                       v0 = v1;
+               }
+               else {
+                       ucnt = 0;
+               }
        }
        /*NOTREACHED*/
 }
+
 /*
  * inittodr:
  *
@@ -247,6 +253,7 @@
        time.tv_sec = base;
        time.tv_usec = 0;
 }
+
 /*
  * resettodr:
  *
@@ -270,9 +277,10 @@
 void
 cpu_initclocks()
 {
-       struct s3c2800_softc *sc = (struct s3c2800_softc *) s3c2xx0_softc;
+       struct s3c2800_softc *sc = (struct s3c2800_softc *)s3c2xx0_softc;
        long tc;
        int prescaler;
+       int pclk = s3c2xx0_softc->sc_pclk;
 
        stathz = STATHZ;
        profhz = stathz;
@@ -282,37 +290,41 @@
                prescaler = 1;                                  \
                do {                                            \
                        ++prescaler;                            \
-                       tc = TIMER_FREQUENCY /(hz)/ prescaler;  \
+                       tc = TIMER_FREQUENCY(pclk) /(hz)/ prescaler;    \
                } while( tc > 65536 );                          \
        } while(0)
 
 
 
        /* Use the channels 0 and 1 for hardclock and statclock, respectively */
+       bus_space_write_4(sc->sc_sx.sc_iot, sc->sc_tmr0_ioh, TIMER_TMCON, 0);
+       bus_space_write_4(sc->sc_sx.sc_iot, sc->sc_tmr1_ioh, TIMER_TMCON, 0);
+
        calc_time_constant(hz);
        bus_space_write_4(sc->sc_sx.sc_iot, sc->sc_tmr0_ioh, TIMER_TMDAT,
            ((prescaler - 1) << 16) | (tc - 1));
        timer0_prescaler = prescaler;
        timer0_reload_value = tc;
+       timer0_mseccount = TIMER_FREQUENCY(pclk)/timer0_prescaler/1000 ;
 
        printf("clock: hz=%d stathz = %d PCLK=%d prescaler=%d tc=%ld\n",
-           hz, stathz, PCLK, prescaler, tc);
+           hz, stathz, pclk, prescaler, tc);
 
        calc_time_constant(stathz);
        bus_space_write_4(sc->sc_sx.sc_iot, sc->sc_tmr1_ioh, TIMER_TMDAT,
            ((prescaler - 1) << 16) | (tc - 1));
 
 
-       s3c2800_intr_establish(S3C2800_INT_TIMER0, IPL_CLOCK, IST_EDGE, 
-           hardintr, 0);
-       s3c2800_intr_establish(S3C2800_INT_TIMER1, IPL_STATCLOCK, IST_EDGE,
-           statintr, 0);
+       s3c2800_intr_establish(S3C2800_INT_TIMER0, IPL_CLOCK, 
+                              IST_NONE, hardintr, 0);
+       s3c2800_intr_establish(S3C2800_INT_TIMER1, IPL_STATCLOCK,
+                              IST_NONE, statintr, 0);
 
        /* start timers */
-       bus_space_write_4(sc->sc_sx.sc_iot, sc->sc_tmr0_ioh, TIMER_TMCON,
-           TMCON_MUX_DIV4 | TMCON_INTENA | TMCON_ENABLE);
-       bus_space_write_4(sc->sc_sx.sc_iot, sc->sc_tmr1_ioh, TIMER_TMCON,
-           TMCON_MUX_DIV4 | TMCON_INTENA | TMCON_ENABLE);
+       bus_space_write_4(sc->sc_sx.sc_iot, sc->sc_tmr0_ioh, TIMER_TMCON, 
+           TMCON_MUX_DIV32|TMCON_INTENA|TMCON_ENABLE);
+       bus_space_write_4(sc->sc_sx.sc_iot, sc->sc_tmr1_ioh, TIMER_TMCON, 
+           TMCON_MUX_DIV4|TMCON_INTENA|TMCON_ENABLE);
 
        /* stop timer2 */
        {