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: releng/11.0/sys/dev/psci/psci.c 286630 2015-08-11 13:42:58Z 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 psci_callfn_t 106psci_get_callfn(phandle_t node) 107{ 108 char method[16]; 109 110 if ((OF_getprop(node, "method", method, sizeof(method))) > 0) { 111 if (strcmp(method, "hvc") == 0) 112 return (psci_hvc_despatch); 113 else if (strcmp(method, "smc") == 0) 114 return (psci_smc_despatch); 115 else 116 printf("psci: PSCI conduit \"%s\" invalid\n", method); 117 } else 118 printf("psci: PSCI conduit not supplied in the device tree\n"); 119 120 return (NULL); 121} 122 123static int 124psci_probe(device_t dev) 125{ 126 const struct ofw_compat_data *ocd; 127 128 if (!ofw_bus_status_okay(dev)) 129 return (ENXIO); 130 131 ocd = ofw_bus_search_compatible(dev, compat_data); 132 if (ocd->ocd_str == NULL) 133 return (ENXIO); 134 135 device_set_desc(dev, "ARM Power State Co-ordination Interface Driver"); 136 137 return (BUS_PROBE_SPECIFIC); 138} 139 140static int 141psci_attach(device_t dev) 142{ 143 struct psci_softc *sc = device_get_softc(dev); 144 const struct ofw_compat_data *ocd; 145 psci_initfn_t psci_init; 146 phandle_t node; 147 148 if (psci_softc != NULL) 149 return (ENXIO); 150 151 ocd = ofw_bus_search_compatible(dev, compat_data); 152 psci_init = (psci_initfn_t)ocd->ocd_data; 153 KASSERT(psci_init != NULL, ("PSCI init function cannot be NULL")); 154 155 node = ofw_bus_get_node(dev); 156 sc->psci_call = psci_get_callfn(node); 157 if (sc->psci_call == NULL) 158 return (ENXIO); 159 160 if (psci_init(dev)) 161 return (ENXIO); 162 163 psci_softc = sc; 164 165 return (0); 166} 167 168static int 169psci_get_version(struct psci_softc *sc) 170{ 171 uint32_t fnid; 172 173 /* PSCI version wasn't supported in v0.1. */ 174 fnid = sc->psci_fnids[PSCI_FN_VERSION]; 175 if (fnid) 176 return (sc->psci_call(fnid, 0, 0, 0)); 177 178 return (PSCI_RETVAL_NOT_SUPPORTED); 179} 180 181int 182psci_cpu_on(unsigned long cpu, unsigned long entry, unsigned long context_id) 183{ 184 psci_callfn_t callfn; 185 phandle_t node; 186 uint32_t fnid; 187 188 if (psci_softc == NULL) { 189 node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-0.2"); 190 if (node == 0) 191 /* TODO: Handle psci 0.1 */ 192 return (PSCI_RETVAL_INTERNAL_FAILURE); 193 194 fnid = PSCI_FNID_CPU_ON; 195 callfn = psci_get_callfn(node); 196 if (callfn == NULL) 197 return (PSCI_RETVAL_INTERNAL_FAILURE); 198 } else { 199 callfn = psci_softc->psci_call; 200 fnid = psci_softc->psci_fnids[PSCI_FN_CPU_ON]; 201 } 202 203 /* PSCI v0.1 and v0.2 both support cpu_on. */ 204 return (callfn(fnid, cpu, entry, context_id)); 205} 206 207static void 208psci_shutdown(void *xsc, int howto) 209{ 210 uint32_t fn = 0; 211 212 /* PSCI system_off and system_reset werent't supported in v0.1. */ 213 if ((howto & RB_POWEROFF) != 0) 214 fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_OFF]; 215 else if ((howto & RB_HALT) == 0) 216 fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_RESET]; 217 218 if (fn) 219 psci_softc->psci_call(fn, 0, 0, 0); 220 221 /* System reset and off do not return. */ 222} 223 224static int 225psci_v0_1_init(device_t dev) 226{ 227 struct psci_softc *sc = device_get_softc(dev); 228 int psci_fn; 229 uint32_t psci_fnid; 230 phandle_t node; 231 int len; 232 233 234 /* Zero out the function ID table - Is this needed ? */ 235 for (psci_fn = PSCI_FN_VERSION, psci_fnid = PSCI_FNID_VERSION; 236 psci_fn < PSCI_FN_MAX; psci_fn++, psci_fnid++) 237 sc->psci_fnids[psci_fn] = 0; 238 239 /* PSCI v0.1 doesn't specify function IDs. Get them from DT */ 240 node = ofw_bus_get_node(dev); 241 242 if ((len = OF_getproplen(node, "cpu_suspend")) > 0) { 243 OF_getencprop(node, "cpu_suspend", &psci_fnid, len); 244 sc->psci_fnids[PSCI_FN_CPU_SUSPEND] = psci_fnid; 245 } 246 247 if ((len = OF_getproplen(node, "cpu_on")) > 0) { 248 OF_getencprop(node, "cpu_on", &psci_fnid, len); 249 sc->psci_fnids[PSCI_FN_CPU_ON] = psci_fnid; 250 } 251 252 if ((len = OF_getproplen(node, "cpu_off")) > 0) { 253 OF_getencprop(node, "cpu_off", &psci_fnid, len); 254 sc->psci_fnids[PSCI_FN_CPU_OFF] = psci_fnid; 255 } 256 257 if ((len = OF_getproplen(node, "migrate")) > 0) { 258 OF_getencprop(node, "migrate", &psci_fnid, len); 259 sc->psci_fnids[PSCI_FN_MIGRATE] = psci_fnid; 260 } 261 262 if (bootverbose) 263 device_printf(dev, "PSCI version 0.1 available\n"); 264 265 return(0); 266} 267 268static int 269psci_v0_2_init(device_t dev) 270{ 271 struct psci_softc *sc = device_get_softc(dev); 272 int version; 273 274 /* PSCI v0.2 specifies explicit function IDs. */ 275 sc->psci_fnids[PSCI_FN_VERSION] = PSCI_FNID_VERSION; 276 sc->psci_fnids[PSCI_FN_CPU_SUSPEND] = PSCI_FNID_CPU_SUSPEND; 277 sc->psci_fnids[PSCI_FN_CPU_OFF] = PSCI_FNID_CPU_OFF; 278 sc->psci_fnids[PSCI_FN_CPU_ON] = PSCI_FNID_CPU_ON; 279 sc->psci_fnids[PSCI_FN_AFFINITY_INFO] = PSCI_FNID_AFFINITY_INFO; 280 sc->psci_fnids[PSCI_FN_MIGRATE] = PSCI_FNID_MIGRATE; 281 sc->psci_fnids[PSCI_FN_MIGRATE_INFO_TYPE] = PSCI_FNID_MIGRATE_INFO_TYPE; 282 sc->psci_fnids[PSCI_FN_MIGRATE_INFO_UP_CPU] = PSCI_FNID_MIGRATE_INFO_UP_CPU; 283 sc->psci_fnids[PSCI_FN_SYSTEM_OFF] = PSCI_FNID_SYSTEM_OFF; 284 sc->psci_fnids[PSCI_FN_SYSTEM_RESET] = PSCI_FNID_SYSTEM_RESET; 285 286 version = psci_get_version(sc); 287 288 if (version == PSCI_RETVAL_NOT_SUPPORTED) 289 return (1); 290 291 if ((PSCI_VER_MAJOR(version) == 0 && PSCI_VER_MINOR(version) == 2) || 292 (PSCI_VER_MAJOR(version) == 1 && PSCI_VER_MINOR(version) == 0)) { 293 if (bootverbose) 294 device_printf(dev, "PSCI version 0.2 available\n"); 295 296 /* 297 * We only register this for v0.2 since v0.1 doesn't support 298 * system_reset. 299 */ 300 EVENTHANDLER_REGISTER(shutdown_final, psci_shutdown, sc, 301 SHUTDOWN_PRI_LAST); 302 303 return (0); 304 } 305 306 device_printf(dev, "PSCI version number mismatched with DT\n"); 307 return (1); 308} 309