1 /* $NetBSD: cpu_speedctl.c,v 1.3 2020/07/06 10:58:06 rin Exp $ */ 2 3 /*- 4 * Copyright (c) 2006 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: cpu_speedctl.c,v 1.3 2020/07/06 10:58:06 rin Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/device.h> 35 #include <sys/types.h> 36 37 #include <powerpc/psl.h> 38 #include <powerpc/spr.h> 39 #include <powerpc/oea/cpufeat.h> 40 #include <powerpc/oea/spr.h> 41 42 #include <sys/sysctl.h> 43 #include <dev/ofw/openfirm.h> 44 45 void init_scom_speedctl(void); 46 static int scom_speedctl = 0; 47 static uint32_t scom_speeds[2]; 48 static uint32_t scom_reg[2]; 49 static int sysctl_cpuspeed_temp(SYSCTLFN_ARGS); 50 static int sysctl_cpuspeed_cur(SYSCTLFN_ARGS); 51 static int sysctl_cpuspeed_available(SYSCTLFN_ARGS); 52 53 void 54 init_scom_speedctl(void) 55 { 56 int node; 57 const struct sysctlnode *sysctl_node, *me, *freq; 58 59 /* do this only once */ 60 if (scom_speedctl != 0) return; 61 scom_speedctl = 1; 62 63 node = OF_finddevice("/cpus/@0"); 64 if (OF_getprop(node, "power-mode-data", scom_reg, 8) != 8) 65 return; 66 if (OF_getprop(node, "clock-frequency", scom_speeds, 4) != 4) 67 return; 68 scom_speeds[0] = scom_speeds[0] / 1000000; /* Hz -> MHz */ 69 scom_speeds[1] = scom_speeds[0] / 2; 70 71 sysctl_node = NULL; 72 73 if (sysctl_createv(NULL, 0, NULL, 74 &me, 75 CTLFLAG_READWRITE, CTLTYPE_NODE, "cpu", NULL, NULL, 76 0, NULL, 0, CTL_MACHDEP, CTL_CREATE, CTL_EOL) != 0) 77 printf("couldn't create 'cpu' node\n"); 78 79 if (sysctl_createv(NULL, 0, NULL, 80 &freq, 81 CTLFLAG_READWRITE, CTLTYPE_NODE, "frequency", NULL, NULL, 82 0, NULL, 0, CTL_MACHDEP, me->sysctl_num, CTL_CREATE, CTL_EOL) != 0) 83 printf("couldn't create 'frequency' node\n"); 84 85 if (sysctl_createv(NULL, 0, NULL, 86 &sysctl_node, 87 CTLFLAG_READWRITE | CTLFLAG_OWNDESC, 88 CTLTYPE_INT, "target", "CPU speed", sysctl_cpuspeed_temp, 89 0, NULL, 0, CTL_MACHDEP, me->sysctl_num, freq->sysctl_num, 90 CTL_CREATE, CTL_EOL) == 0) { 91 } else 92 printf("couldn't create 'target' node\n"); 93 94 if (sysctl_createv(NULL, 0, NULL, 95 &sysctl_node, 96 CTLFLAG_READWRITE, 97 CTLTYPE_INT, "current", NULL, sysctl_cpuspeed_cur, 98 1, NULL, 0, CTL_MACHDEP, me->sysctl_num, freq->sysctl_num, 99 CTL_CREATE, CTL_EOL) == 0) { 100 } else 101 printf("couldn't create 'current' node\n"); 102 103 if (sysctl_createv(NULL, 0, NULL, 104 &sysctl_node, 105 CTLFLAG_READWRITE, 106 CTLTYPE_STRING, "available", NULL, sysctl_cpuspeed_available, 107 2, NULL, 0, CTL_MACHDEP, me->sysctl_num, freq->sysctl_num, 108 CTL_CREATE, CTL_EOL) == 0) { 109 } else 110 printf("couldn't create 'available' node\n"); 111 } 112 113 static int 114 sysctl_cpuspeed_temp(SYSCTLFN_ARGS) 115 { 116 struct sysctlnode node = *rnode; 117 int speed, nspeed = -1, mhz; 118 119 speed = (scom_read(SCOM_PSR) >> 56) & 3; 120 if (speed > 1) speed = 1; 121 mhz = scom_speeds[speed]; 122 node.sysctl_data = &mhz; 123 124 if (sysctl_lookup(SYSCTLFN_CALL(&node)) == 0) { 125 int new_reg; 126 127 new_reg = *(int *)node.sysctl_data; 128 if (new_reg == scom_speeds[0]) { 129 nspeed = 0; 130 } else if (new_reg == scom_speeds[1]) { 131 nspeed = 1; 132 } else { 133 printf("%s: new_reg %d\n", __func__, new_reg); 134 return EINVAL; 135 } 136 if (nspeed != speed) { 137 volatile uint64_t junk; 138 scom_write(SCOM_PCR, 0x80000000); 139 scom_write(SCOM_PCR, scom_reg[nspeed]); 140 junk = scom_read(SCOM_PSR); 141 __USE(junk); 142 } 143 return 0; 144 } 145 return EINVAL; 146 } 147 148 static int 149 sysctl_cpuspeed_cur(SYSCTLFN_ARGS) 150 { 151 struct sysctlnode node = *rnode; 152 uint64_t speed; 153 int mhz; 154 155 speed = (scom_read(SCOM_PSR) >> 56) & 3; 156 if (speed > 1) speed = 1; 157 158 mhz = scom_speeds[speed]; 159 node.sysctl_data = &mhz; 160 return sysctl_lookup(SYSCTLFN_CALL(&node)); 161 } 162 163 static int 164 sysctl_cpuspeed_available(SYSCTLFN_ARGS) 165 { 166 struct sysctlnode node = *rnode; 167 char buf[128]; 168 169 snprintf(buf, 128, "%d %d", scom_speeds[0], scom_speeds[1]); 170 node.sysctl_data = buf; 171 return(sysctl_lookup(SYSCTLFN_CALL(&node))); 172 } 173 174 SYSCTL_SETUP(sysctl_ams_setup, "sysctl obio subtree setup") 175 { 176 177 sysctl_createv(NULL, 0, NULL, NULL, 178 CTLFLAG_PERMANENT, 179 CTLTYPE_NODE, "machdep", NULL, 180 NULL, 0, NULL, 0, 181 CTL_MACHDEP, CTL_EOL); 182 } 183