1 /* $NetBSD: tegra_cpufreq.c,v 1.4 2016/11/21 04:10:05 ozaki-r Exp $ */ 2 3 /*- 4 * Copyright (c) 2015 Jared D. McNeill <jmcneill@invisible.ca> 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 AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include "locators.h" 30 31 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: tegra_cpufreq.c,v 1.4 2016/11/21 04:10:05 ozaki-r Exp $"); 33 34 #include <sys/param.h> 35 #include <sys/bus.h> 36 #include <sys/device.h> 37 #include <sys/intr.h> 38 #include <sys/systm.h> 39 #include <sys/kernel.h> 40 #include <sys/atomic.h> 41 #include <sys/kmem.h> 42 #include <sys/sysctl.h> 43 44 #include <arm/nvidia/tegra_var.h> 45 46 static u_int cpufreq_busy; 47 static struct sysctllog *cpufreq_log; 48 static int cpufreq_node_target, cpufreq_node_current, cpufreq_node_available; 49 50 static const struct tegra_cpufreq_func *cpufreq_func = NULL; 51 52 static int tegra_cpufreq_freq_helper(SYSCTLFN_PROTO); 53 static char tegra_cpufreq_available[TEGRA_CPUFREQ_MAX * 5]; 54 55 #define cpufreq_set_rate cpufreq_func->set_rate 56 #define cpufreq_get_rate cpufreq_func->get_rate 57 #define cpufreq_get_available cpufreq_func->get_available 58 59 void 60 tegra_cpufreq_register(const struct tegra_cpufreq_func *cf) 61 { 62 KASSERT(cpufreq_func == NULL); 63 cpufreq_func = cf; 64 } 65 66 void 67 tegra_cpufreq_init(void) 68 { 69 const struct sysctlnode *node, *cpunode, *freqnode; 70 u_int availfreq[TEGRA_CPUFREQ_MAX]; 71 size_t nfreq; 72 int error; 73 74 if (cpufreq_func == NULL) 75 return; 76 77 nfreq = cpufreq_get_available(availfreq, TEGRA_CPUFREQ_MAX); 78 if (nfreq == 0) 79 return; 80 81 KASSERT(nfreq <= TEGRA_CPUFREQ_MAX); 82 83 for (int i = 0; i < nfreq; i++) { 84 char buf[6]; 85 snprintf(buf, sizeof(buf), i ? " %u" : "%u", availfreq[i]); 86 strcat(tegra_cpufreq_available, buf); 87 } 88 89 error = sysctl_createv(&cpufreq_log, 0, NULL, &node, 90 CTLFLAG_PERMANENT, CTLTYPE_NODE, "machdep", NULL, 91 NULL, 0, NULL, 0, CTL_MACHDEP, CTL_EOL); 92 if (error) 93 goto sysctl_failed; 94 error = sysctl_createv(&cpufreq_log, 0, &node, &cpunode, 95 0, CTLTYPE_NODE, "cpu", NULL, 96 NULL, 0, NULL, 0, CTL_CREATE, CTL_EOL); 97 if (error) 98 goto sysctl_failed; 99 error = sysctl_createv(&cpufreq_log, 0, &cpunode, &freqnode, 100 0, CTLTYPE_NODE, "frequency", NULL, 101 NULL, 0, NULL, 0, CTL_CREATE, CTL_EOL); 102 if (error) 103 goto sysctl_failed; 104 105 error = sysctl_createv(&cpufreq_log, 0, &freqnode, &node, 106 CTLFLAG_READWRITE, CTLTYPE_INT, "target", NULL, 107 tegra_cpufreq_freq_helper, 0, NULL, 0, 108 CTL_CREATE, CTL_EOL); 109 if (error) 110 goto sysctl_failed; 111 cpufreq_node_target = node->sysctl_num; 112 113 error = sysctl_createv(&cpufreq_log, 0, &freqnode, &node, 114 CTLFLAG_READWRITE, CTLTYPE_INT, "current", NULL, 115 tegra_cpufreq_freq_helper, 0, NULL, 0, 116 CTL_CREATE, CTL_EOL); 117 if (error) 118 goto sysctl_failed; 119 cpufreq_node_current = node->sysctl_num; 120 121 error = sysctl_createv(&cpufreq_log, 0, &freqnode, &node, 122 0, CTLTYPE_STRING, "available", NULL, 123 NULL, 0, tegra_cpufreq_available, 0, 124 CTL_CREATE, CTL_EOL); 125 if (error) 126 goto sysctl_failed; 127 cpufreq_node_available = node->sysctl_num; 128 129 device_printf(curcpu()->ci_dev, 130 "setting speed to %d MHz\n", availfreq[0]); 131 cpufreq_set_rate(availfreq[0]); 132 133 return; 134 135 sysctl_failed: 136 aprint_error("cpufreq: couldn't create sysctl nodes (%d)\n", error); 137 sysctl_teardown(&cpufreq_log); 138 } 139 140 static int 141 tegra_cpufreq_freq_helper(SYSCTLFN_ARGS) 142 { 143 struct sysctlnode node; 144 int fq, oldfq = 0, error; 145 146 node = *rnode; 147 node.sysctl_data = &fq; 148 149 fq = cpufreq_get_rate(); 150 if (rnode->sysctl_num == cpufreq_node_target) 151 oldfq = fq; 152 153 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 154 if (error || newp == NULL) 155 return error; 156 157 if (fq == oldfq || rnode->sysctl_num != cpufreq_node_target) 158 return 0; 159 160 if (atomic_cas_uint(&cpufreq_busy, 0, 1) != 0) 161 return EBUSY; 162 163 error = cpufreq_set_rate(fq); 164 if (error == 0) { 165 pmf_event_inject(NULL, PMFE_SPEED_CHANGED); 166 } 167 168 atomic_dec_uint(&cpufreq_busy); 169 170 return error; 171 } 172