Soby Mathew | 200fffd | 2016-10-21 11:34:59 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved. |
| 3 | * |
| 4 | * Redistribution and use in source and binary forms, with or without |
| 5 | * modification, are permitted provided that the following conditions are met: |
| 6 | * |
| 7 | * Redistributions of source code must retain the above copyright notice, this |
| 8 | * list of conditions and the following disclaimer. |
| 9 | * |
| 10 | * Redistributions in binary form must reproduce the above copyright notice, |
| 11 | * this list of conditions and the following disclaimer in the documentation |
| 12 | * and/or other materials provided with the distribution. |
| 13 | * |
| 14 | * Neither the name of ARM nor the names of its contributors may be used |
| 15 | * to endorse or promote products derived from this software without specific |
| 16 | * prior written permission. |
| 17 | * |
| 18 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| 19 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 20 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 21 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
| 22 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 23 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 24 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 25 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 26 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 27 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 28 | * POSSIBILITY OF SUCH DAMAGE. |
| 29 | */ |
| 30 | |
| 31 | #include <arch_helpers.h> |
| 32 | #include <assert.h> |
| 33 | #include <css_pm.h> |
| 34 | #include <debug.h> |
| 35 | #include "../scpi/css_scpi.h" |
| 36 | #include "css_scp.h" |
| 37 | |
| 38 | /* |
| 39 | * This file implements the SCP power management functions using SCPI protocol. |
| 40 | */ |
| 41 | |
| 42 | /* |
| 43 | * Helper function to inform power down state to SCP. |
| 44 | */ |
| 45 | void css_scp_suspend(const psci_power_state_t *target_state) |
| 46 | { |
| 47 | uint32_t cluster_state = scpi_power_on; |
| 48 | uint32_t system_state = scpi_power_on; |
| 49 | |
| 50 | /* Check if power down at system power domain level is requested */ |
| 51 | if (CSS_SYSTEM_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF) |
| 52 | system_state = scpi_power_retention; |
| 53 | |
| 54 | /* Cluster is to be turned off, so disable coherency */ |
| 55 | if (CSS_CLUSTER_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF) |
| 56 | cluster_state = scpi_power_off; |
| 57 | |
| 58 | /* |
| 59 | * Ask the SCP to power down the appropriate components depending upon |
| 60 | * their state. |
| 61 | */ |
| 62 | scpi_set_css_power_state(read_mpidr_el1(), |
| 63 | scpi_power_off, |
| 64 | cluster_state, |
| 65 | system_state); |
| 66 | } |
| 67 | |
| 68 | /* |
| 69 | * Helper function to turn off a CPU power domain and its parent power domains |
| 70 | * if applicable. Since SCPI doesn't differentiate between OFF and suspend, we |
| 71 | * call the suspend helper here. |
| 72 | */ |
| 73 | void css_scp_off(const psci_power_state_t *target_state) |
| 74 | { |
| 75 | css_scp_suspend(target_state); |
| 76 | } |
| 77 | |
| 78 | /* |
| 79 | * Helper function to turn ON a CPU power domain and its parent power domains |
| 80 | * if applicable. |
| 81 | */ |
| 82 | void css_scp_on(u_register_t mpidr) |
| 83 | { |
| 84 | /* |
| 85 | * SCP takes care of powering up parent power domains so we |
| 86 | * only need to care about level 0 |
| 87 | */ |
| 88 | scpi_set_css_power_state(mpidr, scpi_power_on, scpi_power_on, |
| 89 | scpi_power_on); |
| 90 | } |
| 91 | |
| 92 | /* |
| 93 | * Helper function to get the power state of a power domain node as reported |
| 94 | * by the SCP. |
| 95 | */ |
| 96 | int css_scp_get_power_state(u_register_t mpidr, unsigned int power_level) |
| 97 | { |
| 98 | int rc, element; |
| 99 | unsigned int cpu_state, cluster_state; |
| 100 | |
| 101 | /* |
| 102 | * The format of 'power_level' is implementation-defined, but 0 must |
| 103 | * mean a CPU. We also allow 1 to denote the cluster |
| 104 | */ |
| 105 | if (power_level != ARM_PWR_LVL0 && power_level != ARM_PWR_LVL1) |
| 106 | return PSCI_E_INVALID_PARAMS; |
| 107 | |
| 108 | /* Query SCP */ |
| 109 | rc = scpi_get_css_power_state(mpidr, &cpu_state, &cluster_state); |
| 110 | if (rc != 0) |
| 111 | return PSCI_E_INVALID_PARAMS; |
| 112 | |
| 113 | /* Map power states of CPU and cluster to expected PSCI return codes */ |
| 114 | if (power_level == ARM_PWR_LVL0) { |
| 115 | /* |
| 116 | * The CPU state returned by SCP is an 8-bit bit mask |
| 117 | * corresponding to each CPU in the cluster |
| 118 | */ |
| 119 | element = mpidr & MPIDR_AFFLVL_MASK; |
| 120 | return CSS_CPU_PWR_STATE(cpu_state, element) == |
| 121 | CSS_CPU_PWR_STATE_ON ? HW_ON : HW_OFF; |
| 122 | } else { |
| 123 | assert(cluster_state == CSS_CLUSTER_PWR_STATE_ON || |
| 124 | cluster_state == CSS_CLUSTER_PWR_STATE_OFF); |
| 125 | return cluster_state == CSS_CLUSTER_PWR_STATE_ON ? HW_ON : |
| 126 | HW_OFF; |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | /* |
| 131 | * Helper function to shutdown the system via SCPI. |
| 132 | */ |
| 133 | void __dead2 css_scp_sys_shutdown(void) |
| 134 | { |
| 135 | uint32_t response; |
| 136 | |
| 137 | /* Send the power down request to the SCP */ |
| 138 | response = scpi_sys_power_state(scpi_system_shutdown); |
| 139 | |
| 140 | if (response != SCP_OK) { |
| 141 | ERROR("CSS System Off: SCP error %u.\n", response); |
| 142 | panic(); |
| 143 | } |
| 144 | wfi(); |
| 145 | ERROR("CSS System Off: operation not handled.\n"); |
| 146 | panic(); |
| 147 | } |
| 148 | |
| 149 | /* |
| 150 | * Helper function to reset the system via SCPI. |
| 151 | */ |
| 152 | void __dead2 css_scp_sys_reboot(void) |
| 153 | { |
| 154 | uint32_t response; |
| 155 | |
| 156 | /* Send the system reset request to the SCP */ |
| 157 | response = scpi_sys_power_state(scpi_system_reboot); |
| 158 | |
| 159 | if (response != SCP_OK) { |
| 160 | ERROR("CSS System Reset: SCP error %u.\n", response); |
| 161 | panic(); |
| 162 | } |
| 163 | wfi(); |
| 164 | ERROR("CSS System Reset: operation not handled.\n"); |
| 165 | panic(); |
| 166 | } |