| Soby Mathew | 0d78607 | 2016-03-24 16:56:29 +0000 | [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.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 | } |