sys/arch/arm/ofw/ofwgencfg_clock.c

   1 /*      $NetBSD: ofwgencfg_clock.c,v 1.9 2009/03/14 15:36:02 dsl Exp $  */
   2
   3 /*
   4  * Copyright 1997
   5  * Digital Equipment Corporation. All rights reserved.
   6  *
   7  * This software is furnished under license and may be used and
   8  * copied only in accordance with the following terms and conditions.
   9  * Subject to these conditions, you may download, copy, install,
  10  * use, modify and distribute this software in source and/or binary
  11  * form. No title or ownership is transferred hereby.
  12  *
  13  * 1) Any source code used, modified or distributed must reproduce
  14  *    and retain this copyright notice and list of conditions as
  15  *    they appear in the source file.
  16  *
  17  * 2) No right is granted to use any trade name, trademark, or logo of
  18  *    Digital Equipment Corporation. Neither the "Digital Equipment
  19  *    Corporation" name nor any trademark or logo of Digital Equipment
  20  *    Corporation may be used to endorse or promote products derived
  21  *    from this software without the prior written permission of
  22  *    Digital Equipment Corporation.
  23  *
  24  * 3) This software is provided "AS-IS" and any express or implied
  25  *    warranties, including but not limited to, any implied warranties
  26  *    of merchantability, fitness for a particular purpose, or
  27  *    non-infringement are disclaimed. In no event shall DIGITAL be
  28  *    liable for any damages whatsoever, and in particular, DIGITAL
  29  *    shall not be liable for special, indirect, consequential, or
  30  *    incidental damages or damages for lost profits, loss of
  31  *    revenue or loss of use, whether such damages arise in contract,
  32  *    negligence, tort, under statute, in equity, at law or otherwise,
  33  *    even if advised of the possibility of such damage.
  34  */
  35
  36 /* Include header files */
  37
  38 #include <sys/cdefs.h>
  39 __KERNEL_RCSID(0, "$NetBSD: ofwgencfg_clock.c,v 1.9 2009/03/14 15:36:02 dsl Exp $");
  40
  41 #include <sys/types.h>
  42 #include <sys/param.h>
  43 #include <sys/systm.h>
  44 #include <sys/kernel.h>
  45 #include <sys/time.h>
  46
  47 #include <machine/intr.h>
  48 #include <machine/irqhandler.h>
  49 #include <arm/cpufunc.h>
  50 #include <machine/cpu.h>
  51 #include <machine/ofw.h>
  52
  53 static void *clockirq;
  54
  55
  56 /*
  57  * int clockhandler(struct clockframe *frame)
  58  *
  59  * Function called by timer 0 interrupts. This just calls
  60  * hardclock(). Eventually the irqhandler can call hardclock() directly
  61  * but for now we use this function so that we can debug IRQ's
  62  */
  63
  64 static int
  65 clockhandler(struct clockframe *frame)
  66 {
  67
  68         hardclock(frame);
  69         return(0);      /* Pass the interrupt on down the chain */
  70 }
  71
  72 #if 0
  73 /*
  74  * int statclockhandler(struct clockframe *frame)
  75  *
  76  * Function called by timer 1 interrupts. This just calls
  77  * statclock(). Eventually the irqhandler can call statclock() directly
  78  * but for now we use this function so that we can debug IRQ's
  79  */
  80
  81 int
  82 statclockhandler(struct clockframe *frame)
  83 {
  84
  85         statclock(frame);
  86         return(0);      /* Pass the interrupt on down the chain */
  87 }
  88 #endif
  89
  90 /*
  91  * void setstatclockrate(int hz)
  92  *
  93  * Set the stat clock rate. The stat clock uses timer1
  94  */
  95
  96 void
  97 setstatclockrate(int arg)
  98 {
  99 #ifdef  OFWGENCFG
 100         printf("Not setting statclock: OFW generic has only one clock.\n");
 101 #endif
 102 }
 103
 104
 105 /*
 106  * void cpu_initclocks(void)
 107  *
 108  * Initialise the clocks.
 109  * This sets up the two timers in the IOMD and installs the IRQ handlers
 110  *
 111  * NOTE: Currently only timer 0 is setup and the IRQ handler is not installed
 112  */
 113
 114 void
 115 cpu_initclocks(void)
 116 {
 117         /*
 118          * Load timer 0 with count down value
 119          * This timer generates 100Hz interrupts for the system clock
 120          */
 121
 122         printf("clock: hz=%d stathz = %d profhz = %d\n", hz, stathz, profhz);
 123
 124         clockirq = intr_claim(IRQ_TIMER0, IPL_CLOCK,
 125             (int (*)(void *))clockhandler, 0, "clock", "hard intr");
 126         if (clockirq == NULL)
 127                 panic("Cannot installer timer 0 IRQ handler");
 128
 129         /* Notify callback handler that it can start processing ticks. */
 130         ofw_handleticks = 1;
 131
 132         if (stathz) {
 133             printf("Not installing statclock: OFW generic has only one clock.\n");
 134         }
 135 }
 136
 137 /*
 138  * Estimated loop for n microseconds
 139  */
 140
 141 /* Need to re-write this to use the timers */
 142
 143 /* One day soon I will actually do this */
 144
 145 int delaycount = 50;
 146
 147 void
 148 delay(u_int n)
 149 {
 150         u_int i;
 151
 152         if (n == 0) return;
 153         while (n-- > 0) {
 154                 if (cputype == CPU_ID_SA110)    /* XXX - Seriously gross hack */
 155                         for (i = delaycount; --i;);
 156                 else
 157                         for (i = 8; --i;);
 158         }
 159 }