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 uint64_t *hold_base = (uint64_t *)PLAT_RPI3_TM_HOLD_BASE; 135 136 assert(pos < PLATFORM_CORE_COUNT); 137 138 hold_base[pos] = PLAT_RPI3_TM_HOLD_STATE_GO; 139 140 /* Make sure that the write has completed */ 141 dsb(); 142 isb(); 143 144 sev(); 145 146 return rc; 147 } 148 149 /******************************************************************************* 150 * Platform handler called when a power domain has just been powered on after 151 * being turned off earlier. The target_state encodes the low power state that 152 * each level has woken up from. 153 ******************************************************************************/ 154 static void rpi3_pwr_domain_on_finish(const psci_power_state_t *target_state) 155 { 156 assert(target_state->pwr_domain_state[MPIDR_AFFLVL0] == 157 PLAT_LOCAL_STATE_OFF); 158 159 #ifdef RPI_HAVE_GIC 160 gicv2_pcpu_distif_init(); 161 gicv2_cpuif_enable(); 162 #endif 163 } 164 165 /******************************************************************************* 166 * Platform handlers for system reset and system off. 167 ******************************************************************************/ 168 169 /* 10 ticks (Watchdog timer = Timer clock / 16) */ 170 #define RESET_TIMEOUT U(10) 171 172 static void __dead2 rpi3_watchdog_reset(void) 173 { 174 uint32_t rstc; 175 176 console_flush(); 177 178 dsbsy(); 179 isb(); 180 181 mmio_write_32(RPI3_PM_BASE + RPI3_PM_WDOG_OFFSET, 182 RPI3_PM_PASSWORD | RESET_TIMEOUT); 183 184 rstc = mmio_read_32(RPI3_PM_BASE + RPI3_PM_RSTC_OFFSET); 185 rstc &= ~RPI3_PM_RSTC_WRCFG_MASK; 186 rstc |= RPI3_PM_PASSWORD | RPI3_PM_RSTC_WRCFG_FULL_RESET; 187 mmio_write_32(RPI3_PM_BASE + RPI3_PM_RSTC_OFFSET, rstc); 188 189 for (;;) { 190 wfi(); 191 } 192 } 193 194 static void __dead2 rpi3_system_reset(void) 195 { 196 INFO("rpi3: PSCI_SYSTEM_RESET: Invoking watchdog reset\n"); 197 198 rpi3_watchdog_reset(); 199 } 200 201 static void __dead2 rpi3_system_off(void) 202 { 203 uint32_t rsts; 204 205 INFO("rpi3: PSCI_SYSTEM_OFF: Invoking watchdog reset\n"); 206 207 /* 208 * This function doesn't actually make the Raspberry Pi turn itself off, 209 * the hardware doesn't allow it. It simply reboots it and the RSTS 210 * value tells the bootcode.bin firmware not to continue the regular 211 * bootflow and to stay in a low power mode. 212 */ 213 214 rsts = mmio_read_32(RPI3_PM_BASE + RPI3_PM_RSTS_OFFSET); 215 rsts |= RPI3_PM_PASSWORD | RPI3_PM_RSTS_WRCFG_HALT; 216 mmio_write_32(RPI3_PM_BASE + RPI3_PM_RSTS_OFFSET, rsts); 217 218 rpi3_watchdog_reset(); 219 } 220 221 /******************************************************************************* 222 * Platform handlers and setup function. 223 ******************************************************************************/ 224 static const plat_psci_ops_t plat_rpi3_psci_pm_ops = { 225 .cpu_standby = rpi3_cpu_standby, 226 .pwr_domain_off = rpi3_pwr_domain_off, 227 .pwr_domain_on = rpi3_pwr_domain_on, 228 .pwr_domain_on_finish = rpi3_pwr_domain_on_finish, 229 .system_off = rpi3_system_off, 230 .system_reset = rpi3_system_reset, 231 .validate_power_state = rpi3_validate_power_state, 232 }; 233 234 int plat_setup_psci_ops(uintptr_t sec_entrypoint, 235 const plat_psci_ops_t **psci_ops) 236 { 237 uintptr_t *entrypoint = (void *) PLAT_RPI3_TM_ENTRYPOINT; 238 239 *entrypoint = sec_entrypoint; 240 *psci_ops = &plat_rpi3_psci_pm_ops; 241 242 return 0; 243 } 244