1 /* 2 * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <assert.h> 8 9 #include <platform_def.h> 10 11 #include <arch_helpers.h> 12 #include <common/debug.h> 13 #include <drivers/console.h> 14 #include <lib/mmio.h> 15 #include <lib/psci/psci.h> 16 #include <plat/common/platform.h> 17 18 #include <rpi_hw.h> 19 20 #ifdef RPI_HAVE_GIC 21 #include <drivers/arm/gicv2.h> 22 #endif 23 24 /* Make composite power state parameter till power level 0 */ 25 #if PSCI_EXTENDED_STATE_ID 26 27 #define rpi3_make_pwrstate_lvl0(lvl0_state, pwr_lvl, type) \ 28 (((lvl0_state) << PSTATE_ID_SHIFT) | \ 29 ((type) << PSTATE_TYPE_SHIFT)) 30 31 #else 32 33 #define rpi3_make_pwrstate_lvl0(lvl0_state, pwr_lvl, type) \ 34 (((lvl0_state) << PSTATE_ID_SHIFT) | \ 35 ((pwr_lvl) << PSTATE_PWR_LVL_SHIFT) | \ 36 ((type) << PSTATE_TYPE_SHIFT)) 37 38 #endif /* PSCI_EXTENDED_STATE_ID */ 39 40 #define rpi3_make_pwrstate_lvl1(lvl1_state, lvl0_state, pwr_lvl, type) \ 41 (((lvl1_state) << PLAT_LOCAL_PSTATE_WIDTH) | \ 42 rpi3_make_pwrstate_lvl0(lvl0_state, pwr_lvl, type)) 43 44 /* 45 * The table storing the valid idle power states. Ensure that the 46 * array entries are populated in ascending order of state-id to 47 * enable us to use binary search during power state validation. 48 * The table must be terminated by a NULL entry. 49 */ 50 static const unsigned int rpi3_pm_idle_states[] = { 51 /* State-id - 0x01 */ 52 rpi3_make_pwrstate_lvl1(PLAT_LOCAL_STATE_RUN, PLAT_LOCAL_STATE_RET, 53 MPIDR_AFFLVL0, PSTATE_TYPE_STANDBY), 54 /* State-id - 0x02 */ 55 rpi3_make_pwrstate_lvl1(PLAT_LOCAL_STATE_RUN, PLAT_LOCAL_STATE_OFF, 56 MPIDR_AFFLVL0, PSTATE_TYPE_POWERDOWN), 57 /* State-id - 0x22 */ 58 rpi3_make_pwrstate_lvl1(PLAT_LOCAL_STATE_OFF, PLAT_LOCAL_STATE_OFF, 59 MPIDR_AFFLVL1, PSTATE_TYPE_POWERDOWN), 60 0, 61 }; 62 63 /******************************************************************************* 64 * Platform handler called to check the validity of the power state 65 * parameter. The power state parameter has to be a composite power state. 66 ******************************************************************************/ 67 static int rpi3_validate_power_state(unsigned int power_state, 68 psci_power_state_t *req_state) 69 { 70 unsigned int state_id; 71 int i; 72 73 assert(req_state != 0); 74 75 /* 76 * Currently we are using a linear search for finding the matching 77 * entry in the idle power state array. This can be made a binary 78 * search if the number of entries justify the additional complexity. 79 */ 80 for (i = 0; rpi3_pm_idle_states[i] != 0; i++) { 81 if (power_state == rpi3_pm_idle_states[i]) { 82 break; 83 } 84 } 85 86 /* Return error if entry not found in the idle state array */ 87 if (!rpi3_pm_idle_states[i]) { 88 return PSCI_E_INVALID_PARAMS; 89 } 90 91 i = 0; 92 state_id = psci_get_pstate_id(power_state); 93 94 /* Parse the State ID and populate the state info parameter */ 95 while (state_id) { 96 req_state->pwr_domain_state[i++] = state_id & 97 PLAT_LOCAL_PSTATE_MASK; 98 state_id >>= PLAT_LOCAL_PSTATE_WIDTH; 99 } 100 101 return PSCI_E_SUCCESS; 102 } 103 104 /******************************************************************************* 105 * Platform handler called when a CPU is about to enter standby. 106 ******************************************************************************/ 107 static void rpi3_cpu_standby(plat_local_state_t cpu_state) 108 { 109 assert(cpu_state == PLAT_LOCAL_STATE_RET); 110 111 /* 112 * Enter standby state. 113 * dsb is good practice before using wfi to enter low power states 114 */ 115 dsb(); 116 wfi(); 117 } 118 119 static void rpi3_pwr_domain_off(const psci_power_state_t *target_state) 120 { 121 #ifdef RPI_HAVE_GIC 122 gicv2_cpuif_disable(); 123 #endif 124 } 125 126 /******************************************************************************* 127 * Platform handler called when a power domain is about to be turned on. The 128 * mpidr determines the CPU to be turned on. 129 ******************************************************************************/ 130 static int rpi3_pwr_domain_on(u_register_t mpidr) 131 { 132 int rc = PSCI_E_SUCCESS; 133 unsigned int pos = plat_core_pos_by_mpidr(mpidr); 134 uintptr_t hold_base = PLAT_RPI3_TM_HOLD_BASE; 135 136 assert(pos < PLATFORM_CORE_COUNT); 137 138 hold_base += pos * PLAT_RPI3_TM_HOLD_ENTRY_SIZE; 139 140 mmio_write_64(hold_base, PLAT_RPI3_TM_HOLD_STATE_GO); 141 /* No cache maintenance here, hold_base is mapped as device memory. */ 142 143 /* Make sure that the write has completed */ 144 dsb(); 145 isb(); 146 147 sev(); 148 149 return rc; 150 } 151 152 /******************************************************************************* 153 * Platform handler called when a power domain has just been powered on after 154 * being turned off earlier. The target_state encodes the low power state that 155 * each level has woken up from. 156 ******************************************************************************/ 157 static void rpi3_pwr_domain_on_finish(const psci_power_state_t *target_state) 158 { 159 assert(target_state->pwr_domain_state[MPIDR_AFFLVL0] == 160 PLAT_LOCAL_STATE_OFF); 161 162 #ifdef RPI_HAVE_GIC 163 gicv2_pcpu_distif_init(); 164 gicv2_cpuif_enable(); 165 #endif 166 } 167 168 static void __dead2 rpi3_pwr_down_wfi( 169 const psci_power_state_t *target_state) 170 { 171 uintptr_t hold_base = PLAT_RPI3_TM_HOLD_BASE; 172 unsigned int pos = plat_my_core_pos(); 173 174 if (pos == 0) { 175 /* 176 * The secondaries will always be in a wait 177 * for warm boot on reset, but the BSP needs 178 * to be able to distinguish between waiting 179 * for warm boot (e.g. after psci_off, waiting 180 * for psci_on) and a cold boot. 181 */ 182 mmio_write_64(hold_base, PLAT_RPI3_TM_HOLD_STATE_BSP_OFF); 183 /* No cache maintenance here, we run with caches off already. */ 184 dsb(); 185 isb(); 186 } 187 188 write_rmr_el3(RMR_EL3_RR_BIT | RMR_EL3_AA64_BIT); 189 190 while (1) { 191 wfi(); 192 } 193 } 194 195 /******************************************************************************* 196 * Platform handlers for system reset and system off. 197 ******************************************************************************/ 198 199 /* 10 ticks (Watchdog timer = Timer clock / 16) */ 200 #define RESET_TIMEOUT U(10) 201 202 static void __dead2 rpi3_watchdog_reset(void) 203 { 204 uint32_t rstc; 205 206 console_flush(); 207 208 dsbsy(); 209 isb(); 210 211 mmio_write_32(RPI3_PM_BASE + RPI3_PM_WDOG_OFFSET, 212 RPI3_PM_PASSWORD | RESET_TIMEOUT); 213 214 rstc = mmio_read_32(RPI3_PM_BASE + RPI3_PM_RSTC_OFFSET); 215 rstc &= ~RPI3_PM_RSTC_WRCFG_MASK; 216 rstc |= RPI3_PM_PASSWORD | RPI3_PM_RSTC_WRCFG_FULL_RESET; 217 mmio_write_32(RPI3_PM_BASE + RPI3_PM_RSTC_OFFSET, rstc); 218 219 for (;;) { 220 wfi(); 221 } 222 } 223 224 static void __dead2 rpi3_system_reset(void) 225 { 226 INFO("rpi3: PSCI_SYSTEM_RESET: Invoking watchdog reset\n"); 227 228 rpi3_watchdog_reset(); 229 } 230 231 static void __dead2 rpi3_system_off(void) 232 { 233 uint32_t rsts; 234 235 INFO("rpi3: PSCI_SYSTEM_OFF: Invoking watchdog reset\n"); 236 237 /* 238 * This function doesn't actually make the Raspberry Pi turn itself off, 239 * the hardware doesn't allow it. It simply reboots it and the RSTS 240 * value tells the bootcode.bin firmware not to continue the regular 241 * bootflow and to stay in a low power mode. 242 */ 243 244 rsts = mmio_read_32(RPI3_PM_BASE + RPI3_PM_RSTS_OFFSET); 245 rsts |= RPI3_PM_PASSWORD | RPI3_PM_RSTS_WRCFG_HALT; 246 mmio_write_32(RPI3_PM_BASE + RPI3_PM_RSTS_OFFSET, rsts); 247 248 rpi3_watchdog_reset(); 249 } 250 251 /******************************************************************************* 252 * Platform handlers and setup function. 253 ******************************************************************************/ 254 static const plat_psci_ops_t plat_rpi3_psci_pm_ops = { 255 .cpu_standby = rpi3_cpu_standby, 256 .pwr_domain_off = rpi3_pwr_domain_off, 257 .pwr_domain_on = rpi3_pwr_domain_on, 258 .pwr_domain_on_finish = rpi3_pwr_domain_on_finish, 259 .pwr_domain_pwr_down_wfi = rpi3_pwr_down_wfi, 260 .system_off = rpi3_system_off, 261 .system_reset = rpi3_system_reset, 262 .validate_power_state = rpi3_validate_power_state, 263 }; 264 265 int plat_setup_psci_ops(uintptr_t sec_entrypoint, 266 const plat_psci_ops_t **psci_ops) 267 { 268 uintptr_t *entrypoint = (void *) PLAT_RPI3_TM_ENTRYPOINT; 269 270 *entrypoint = sec_entrypoint; 271 *psci_ops = &plat_rpi3_psci_pm_ops; 272 273 return 0; 274 } 275