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      1 /*	$NetBSD: yamon.c,v 1.14 2015/06/26 21:57:25 matt Exp $	*/
      2 
      3 /*
      4  * Copyright 2002 Wasabi Systems, Inc.
      5  * All rights reserved.
      6  *
      7  * Written by Simon Burge for Wasabi Systems, Inc.
      8  *
      9  * Redistribution and use in source and binary forms, with or without
     10  * modification, are permitted provided that the following conditions
     11  * are met:
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice, this list of conditions and the following disclaimer.
     14  * 2. Redistributions in binary form must reproduce the above copyright
     15  *    notice, this list of conditions and the following disclaimer in the
     16  *    documentation and/or other materials provided with the distribution.
     17  * 3. All advertising materials mentioning features or use of this software
     18  *    must display the following acknowledgement:
     19  *      This product includes software developed for the NetBSD Project by
     20  *      Wasabi Systems, Inc.
     21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
     22  *    or promote products derived from this software without specific prior
     23  *    written permission.
     24  *
     25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
     26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
     29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     35  * POSSIBILITY OF SUCH DAMAGE.
     36  */
     37 
     38 /* XXX move to arch/mips/yamon/yamon.c or similar? */
     39 
     40 #include <sys/cdefs.h>
     41 __KERNEL_RCSID(0, "$NetBSD: yamon.c,v 1.14 2015/06/26 21:57:25 matt Exp $");
     42 
     43 #include <sys/param.h>
     44 #include <sys/device.h>
     45 #include <sys/kernel.h>
     46 #include <sys/systm.h>
     47 #include <sys/cpu.h>
     48 
     49 #include <dev/cons.h>
     50 
     51 #include <mips/locore.h>
     52 
     53 #include <machine/yamon.h>
     54 
     55 static int  yamongetc(dev_t);
     56 static void yamonputc(dev_t, int);
     57 
     58 /*
     59  * Default consdev, for errors or warnings before
     60  * consinit runs: use the PROM.
     61  */
     62 struct consdev yamon_promcd = {
     63 	NULL,		/* probe */
     64 	NULL,		/* init */
     65 	yamongetc,	/* getc */
     66 	yamonputc,	/* putc */
     67 	nullcnpollc,	/* pollc */
     68 	NULL,		/* bell */
     69 	makedev(0, 0),
     70 	CN_DEAD,
     71 };
     72 /*
     73  * Get character from PROM console.
     74  */
     75 static int
     76 yamongetc(dev_t dev)
     77 {
     78 	char chr;
     79 
     80 	while (!YAMON_GETCHAR(&chr))
     81 		/* nothing */;
     82 	return chr;
     83 }
     84 
     85 /*
     86  * Print a character on PROM console.
     87  */
     88 static void
     89 yamonputc(dev_t dev, int c)
     90 {
     91 	char chr;
     92 
     93 	chr = c;
     94 	YAMON_PRINT_COUNT(&chr, 1);
     95 }
     96 
     97 char *
     98 yamon_getenv(const char *name)
     99 {
    100 	yamon_env_var *yev = yamon_envp;
    101 
    102 	if (yev == NULL)
    103 		return (NULL);
    104 	while (yev->name != NULL) {
    105 		if (strcmp(yev->name, name) == 0)
    106 			return (yev->val);
    107 		yev++;
    108 	}
    109 
    110 	return (NULL);
    111 }
    112 
    113 void
    114 yamon_print(const char *str)
    115 {
    116 
    117 	YAMON_PRINT(str);
    118 }
    119 
    120 void
    121 yamon_exit(uint32_t rc)
    122 {
    123 
    124 	YAMON_EXIT(rc);
    125 }
    126 
    127 /*
    128  * Ask YAMON for the CPU frequency.
    129  * If "force" is set, then use a random frequency (100MHz) so
    130  * that at least delay() works, even though not perfectly.
    131  * Return 1 if YAMON returns a CPU frequency.
    132  */
    133 int
    134 yamon_setcpufreq(int force)
    135 {
    136 	struct cpu_info * const ci = curcpu();
    137 	uint32_t freq;
    138 	int ret;
    139 
    140 	ret = YAMON_SYSCON_READ(SYSCON_BOARD_CPU_CLOCK_FREQ_ID, &freq,
    141 	    sizeof(freq));
    142 	if (!force && (ret != 0 || freq == 0))
    143 		return 0;
    144 
    145 	if (ret != 0 || freq == 0) {
    146 		freq = 100 * 1000 * 1000;
    147 		ret = 0;
    148 	} else
    149 		ret = 1;
    150 
    151 	ci->ci_cpu_freq = freq;
    152 	ci->ci_cycles_per_hz = (freq + hz / 2) / hz;
    153 	ci->ci_divisor_delay = ((freq + 500000) / 1000000);
    154 	ci->ci_cctr_freq /= ci->ci_cpu_freq;
    155 	if (mips_options.mips_cpu_flags & CPU_MIPS_DOUBLE_COUNT) {
    156 		ci->ci_cycles_per_hz /= 2;
    157 		ci->ci_divisor_delay /= 2;
    158 		ci->ci_cctr_freq /= 2;
    159 	}
    160 
    161 	return ret;
    162 }
    163