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clock.c revision 1.1 
      1 /*	$NetBSD: clock.c,v 1.1 2014/11/22 15:17:02 macallan Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2014 Michael Lorenz
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     26  * POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 #include <sys/cdefs.h>
     30 __KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.1 2014/11/22 15:17:02 macallan Exp $");
     31 
     32 #include <sys/param.h>
     33 #include <sys/cpu.h>
     34 #include <sys/device.h>
     35 #include <sys/kernel.h>
     36 #include <sys/systm.h>
     37 #include <mips/ingenic/ingenic_regs.h>
     38 
     39 void
     40 cpu_initclocks(void)
     41 {
     42 
     43 	/* timecounter setup and such */
     44 }
     45 
     46 /* shamelessly stolen from mips3_clock.c */
     47 void
     48 delay(int n)
     49 {
     50 	u_long divisor_delay;
     51 	uint32_t cur, last, delta, usecs;
     52 
     53 	last = readreg(JZ_OST_CNT_LO);
     54 	delta = usecs = 0;
     55 
     56 	divisor_delay = curcpu()->ci_divisor_delay;
     57 	if (divisor_delay == 0) {
     58 		/*
     59 		 * Frequency values in curcpu() are not initialized.
     60 		 * Assume faster frequency since longer delays are harmless.
     61 		 * Note CPU_MIPS_DOUBLE_COUNT is ignored here.
     62 		 */
     63 #define FAST_FREQ	(300 * 1000 * 1000)	/* fast enough? */
     64 		divisor_delay = FAST_FREQ / (1000 * 1000);
     65 	}
     66 	while (n > usecs) {
     67 		cur = readreg(JZ_OST_CNT_LO);
     68 
     69 		/*
     70 		 * We setup the OS timer to always counts upto UINT32_MAX,
     71 		 * so no need to check wrapped around case.
     72 		 */
     73 		delta += (cur - last);
     74 
     75 		last = cur;
     76 
     77 		while (delta >= divisor_delay) {
     78 			/*
     79 			 * delta is not so larger than divisor_delay here,
     80 			 * and using DIV/DIVU ops could be much slower.
     81 			 * (though longer delay may be harmless)
     82 			 */
     83 			usecs++;
     84 			delta -= divisor_delay;
     85 		}
     86 	}
     87 }
     88 
     89 void
     90 setstatclockrate(int r)
     91 {
     92 	/* nothing to see here */
     93 }
     94