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.h> 32 #include <assert.h> 33 #include <platform.h> 34 #include <psci.h> 35 36 /* 37 * The PSCI generic code uses this API to let the platform participate in state 38 * coordination during a power management operation. It compares the platform 39 * specific local power states requested by each cpu for a given power domain 40 * and returns the coordinated target power state that the domain should 41 * enter. A platform assigns a number to a local power state. This default 42 * implementation assumes that the platform assigns these numbers in order of 43 * increasing depth of the power state i.e. for two power states X & Y, if X < Y 44 * then X represents a shallower power state than Y. As a result, the 45 * coordinated target local power state for a power domain will be the minimum 46 * of the requested local power states. 47 */ 48 plat_local_state_t plat_get_target_pwr_state(unsigned int lvl, 49 const plat_local_state_t *states, 50 unsigned int ncpu) 51 { 52 plat_local_state_t target = PLAT_MAX_OFF_STATE, temp; 53 54 assert(ncpu); 55 56 do { 57 temp = *states++; 58 if (temp < target) 59 target = temp; 60 } while (--ncpu); 61 62 return target; 63 } 64