psci.c revision 281466
1/*- 2 * Copyright (c) 2014 Robin Randhawa 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 */ 27 28/* 29 * This implements support for ARM's Power State Co-ordination Interface 30 * [PSCI]. The implementation adheres to version 0.2 of the PSCI specification 31 * but also supports v0.1. PSCI standardizes operations such as system reset, CPU 32 * on/off/suspend. PSCI requires a compliant firmware implementation. 33 * 34 * The PSCI specification used for this implementation is available at: 35 * 36 * <http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.den0022b/index.html>. 37 * 38 * TODO: 39 * - Add support for remaining PSCI calls [this implementation only 40 * supports get_version, system_reset and cpu_on]. 41 */ 42 43#include <sys/cdefs.h> 44__FBSDID("$FreeBSD: head/sys/dev/psci/psci.c 281466 2015-04-12 13:00:58Z andrew $"); 45 46#include <sys/param.h> 47#include <sys/systm.h> 48#include <sys/bus.h> 49#include <sys/eventhandler.h> 50#include <sys/kernel.h> 51#include <sys/module.h> 52#include <sys/reboot.h> 53 54#include <machine/bus.h> 55 56#include <dev/fdt/fdt_common.h> 57#include <dev/ofw/openfirm.h> 58#include <dev/ofw/ofw_bus.h> 59#include <dev/ofw/ofw_bus_subr.h> 60 61#include <dev/psci/psci.h> 62 63struct psci_softc { 64 device_t dev; 65 66 psci_callfn_t psci_call; 67 uint32_t psci_fnids[PSCI_FN_MAX]; 68}; 69 70static int psci_v0_1_init(device_t dev); 71static int psci_v0_2_init(device_t dev); 72 73struct psci_softc *psci_softc = NULL; 74 75static struct ofw_compat_data compat_data[] = { 76 {"arm,psci-0.2", (uintptr_t)psci_v0_2_init}, 77 {"arm,psci", (uintptr_t)psci_v0_1_init}, 78 {NULL, 0} 79}; 80 81static int psci_probe(device_t dev); 82static int psci_attach(device_t dev); 83static void psci_shutdown(void *, int); 84 85static device_method_t psci_methods[] = { 86 DEVMETHOD(device_probe, psci_probe), 87 DEVMETHOD(device_attach, psci_attach), 88 89 DEVMETHOD_END 90}; 91 92static driver_t psci_driver = { 93 "psci", 94 psci_methods, 95 sizeof(struct psci_softc), 96}; 97 98static devclass_t psci_devclass; 99 100EARLY_DRIVER_MODULE(psci, simplebus, psci_driver, psci_devclass, 0, 0, 101 BUS_PASS_CPU + BUS_PASS_ORDER_FIRST); 102EARLY_DRIVER_MODULE(psci, ofwbus, psci_driver, psci_devclass, 0, 0, 103 BUS_PASS_CPU + BUS_PASS_ORDER_FIRST); 104 105static int 106psci_probe(device_t dev) 107{ 108 const struct ofw_compat_data *ocd; 109 110 if (!ofw_bus_status_okay(dev)) 111 return (ENXIO); 112 113 ocd = ofw_bus_search_compatible(dev, compat_data); 114 if (ocd->ocd_str == NULL) 115 return (ENXIO); 116 117 device_set_desc(dev, "ARM Power State Co-ordination Interface Driver"); 118 119 return (BUS_PROBE_SPECIFIC); 120} 121 122static int 123psci_attach(device_t dev) 124{ 125 struct psci_softc *sc = device_get_softc(dev); 126 const struct ofw_compat_data *ocd; 127 psci_initfn_t psci_init; 128 phandle_t node; 129 char method[16]; 130 131 if (psci_softc != NULL) 132 return (ENXIO); 133 134 ocd = ofw_bus_search_compatible(dev, compat_data); 135 psci_init = (psci_initfn_t)ocd->ocd_data; 136 KASSERT(psci_init != NULL, ("PSCI init function cannot be NULL")); 137 138 node = ofw_bus_get_node(dev); 139 if ((OF_getprop(node, "method", method, sizeof(method))) > 0) { 140 if (strcmp(method, "hvc") == 0) 141 sc->psci_call = psci_hvc_despatch; 142 else if (strcmp(method, "smc") == 0) 143 sc->psci_call = psci_smc_despatch; 144 else { 145 device_printf(dev, 146 "psci_attach: PSCI conduit \"%s\" invalid\n", 147 method); 148 return (ENXIO); 149 } 150 } else { 151 device_printf(dev, 152 "psci_attach: PSCI conduit not supplied in the DT\n"); 153 return (ENXIO); 154 } 155 156 if (psci_init(dev)) 157 return (ENXIO); 158 159 psci_softc = sc; 160 161 return (0); 162} 163 164static int 165psci_get_version(struct psci_softc *sc) 166{ 167 uint32_t fnid; 168 169 /* PSCI version wasn't supported in v0.1. */ 170 fnid = sc->psci_fnids[PSCI_FN_VERSION]; 171 if (fnid) 172 return (sc->psci_call(fnid, 0, 0, 0)); 173 174 return (PSCI_RETVAL_NOT_SUPPORTED); 175} 176 177int 178psci_cpu_on(unsigned long cpu, unsigned long entry, unsigned long context_id) 179{ 180 181 /* PSCI v0.1 and v0.2 both support cpu_on. */ 182 return(psci_softc->psci_call(psci_softc->psci_fnids[PSCI_FN_CPU_ON], cpu, 183 entry, context_id)); 184} 185 186static void 187psci_shutdown(void *xsc, int howto) 188{ 189 uint32_t fn = 0; 190 191 /* PSCI system_off and system_reset werent't supported in v0.1. */ 192 if ((howto & RB_POWEROFF) != 0) 193 fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_OFF]; 194 else if ((howto & RB_HALT) == 0) 195 fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_RESET]; 196 197 if (fn) 198 psci_softc->psci_call(fn, 0, 0, 0); 199 200 /* System reset and off do not return. */ 201} 202 203static int 204psci_v0_1_init(device_t dev) 205{ 206 struct psci_softc *sc = device_get_softc(dev); 207 int psci_fn; 208 uint32_t psci_fnid; 209 phandle_t node; 210 int len; 211 212 213 /* Zero out the function ID table - Is this needed ? */ 214 for (psci_fn = PSCI_FN_VERSION, psci_fnid = PSCI_FNID_VERSION; 215 psci_fn < PSCI_FN_MAX; psci_fn++, psci_fnid++) 216 sc->psci_fnids[psci_fn] = 0; 217 218 /* PSCI v0.1 doesn't specify function IDs. Get them from DT */ 219 node = ofw_bus_get_node(dev); 220 221 if ((len = OF_getproplen(node, "cpu_suspend")) > 0) { 222 OF_getencprop(node, "cpu_suspend", &psci_fnid, len); 223 sc->psci_fnids[PSCI_FN_CPU_SUSPEND] = psci_fnid; 224 } 225 226 if ((len = OF_getproplen(node, "cpu_on")) > 0) { 227 OF_getencprop(node, "cpu_on", &psci_fnid, len); 228 sc->psci_fnids[PSCI_FN_CPU_ON] = psci_fnid; 229 } 230 231 if ((len = OF_getproplen(node, "cpu_off")) > 0) { 232 OF_getencprop(node, "cpu_off", &psci_fnid, len); 233 sc->psci_fnids[PSCI_FN_CPU_OFF] = psci_fnid; 234 } 235 236 if ((len = OF_getproplen(node, "migrate")) > 0) { 237 OF_getencprop(node, "migrate", &psci_fnid, len); 238 sc->psci_fnids[PSCI_FN_MIGRATE] = psci_fnid; 239 } 240 241 if (bootverbose) 242 device_printf(dev, "PSCI version 0.1 available\n"); 243 244 return(0); 245} 246 247static int 248psci_v0_2_init(device_t dev) 249{ 250 struct psci_softc *sc = device_get_softc(dev); 251 int version; 252 253 /* PSCI v0.2 specifies explicit function IDs. */ 254 sc->psci_fnids[PSCI_FN_VERSION] = PSCI_FNID_VERSION; 255 sc->psci_fnids[PSCI_FN_CPU_SUSPEND] = PSCI_FNID_CPU_SUSPEND; 256 sc->psci_fnids[PSCI_FN_CPU_OFF] = PSCI_FNID_CPU_OFF; 257 sc->psci_fnids[PSCI_FN_CPU_ON] = PSCI_FNID_CPU_ON; 258 sc->psci_fnids[PSCI_FN_AFFINITY_INFO] = PSCI_FNID_AFFINITY_INFO; 259 sc->psci_fnids[PSCI_FN_MIGRATE] = PSCI_FNID_MIGRATE; 260 sc->psci_fnids[PSCI_FN_MIGRATE_INFO_TYPE] = PSCI_FNID_MIGRATE_INFO_TYPE; 261 sc->psci_fnids[PSCI_FN_MIGRATE_INFO_UP_CPU] = PSCI_FNID_MIGRATE_INFO_UP_CPU; 262 sc->psci_fnids[PSCI_FN_SYSTEM_OFF] = PSCI_FNID_SYSTEM_OFF; 263 sc->psci_fnids[PSCI_FN_SYSTEM_RESET] = PSCI_FNID_SYSTEM_RESET; 264 265 version = psci_get_version(sc); 266 267 if (version == PSCI_RETVAL_NOT_SUPPORTED) 268 return (1); 269 270 if ((PSCI_VER_MAJOR(version) != 0) && (PSCI_VER_MINOR(version) != 2)) { 271 device_printf(dev, "PSCI version number mismatched with DT\n"); 272 return (1); 273 } 274 275 if (bootverbose) 276 device_printf(dev, "PSCI version 0.2 available\n"); 277 278 /* 279 * We only register this for v0.2 since v0.1 doesn't support 280 * system_reset. 281 */ 282 EVENTHANDLER_REGISTER(shutdown_final, psci_shutdown, sc, 283 SHUTDOWN_PRI_LAST); 284 285 return (0); 286} 287