1 /* 2 * Copyright (c) 2023 Intel Corporation 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 #ifndef ZEPHYR_INCLUDE_KERNEL_SMP_H_ 8 #define ZEPHYR_INCLUDE_KERNEL_SMP_H_ 9 10 #include <stdbool.h> 11 12 typedef void (*smp_init_fn)(void *arg); 13 14 /** 15 * @brief Start a CPU. 16 * 17 * This routine is used to manually start the CPU specified 18 * by @a id. It may be called to restart a CPU that had been 19 * stopped or powered down, as well as some other scenario. 20 * After the CPU has finished initialization, the CPU will be 21 * ready to participate in thread scheduling and execution. 22 * 23 * @note This function must not be used on currently running 24 * CPU. The target CPU must be in off state, or in 25 * certain architectural state(s) where the CPU is 26 * permitted to go through the power up process. 27 * Detection of such state(s) must be provided by 28 * the platform layers. 29 * 30 * @note This initializes per-CPU kernel structs and also 31 * initializes timers needed for MP operations. 32 * Use @ref k_smp_cpu_resume if these are not 33 * desired. 34 * 35 * @param id ID of target CPU. 36 * @param fn Function to be called before letting scheduler 37 * run. 38 * @param arg Argument to @a fn. 39 */ 40 void k_smp_cpu_start(int id, smp_init_fn fn, void *arg); 41 42 /** 43 * @brief Resume a previously suspended CPU. 44 * 45 * This function works like @ref k_smp_cpu_start, but does not 46 * re-initialize the kernel's internal tracking data for 47 * the target CPU. Therefore, @ref k_smp_cpu_start must have 48 * previously been called for the target CPU, and it must have 49 * verifiably reached an idle/off state (detection of which 50 * must be provided by the platform layers). It may be used 51 * in cases where platform layers require, for example, that 52 * data on the interrupt or idle stack be preserved. 53 * 54 * @note This function must not be used on currently running 55 * CPU. The target CPU must be in suspended state, or 56 * in certain architectural state(s) where the CPU is 57 * permitted to go through the resume process. 58 * Detection of such state(s) must be provided by 59 * the platform layers. 60 * 61 * @param id ID of target CPU. 62 * @param fn Function to be called before resuming context. 63 * @param arg Argument to @a fn. 64 * @param reinit_timer True if timer needs to be re-initialized. 65 * @param invoke_sched True if scheduler is invoked after the CPU 66 * has started. 67 */ 68 void k_smp_cpu_resume(int id, smp_init_fn fn, void *arg, 69 bool reinit_timer, bool invoke_sched); 70 71 #endif /* ZEPHYR_INCLUDE_KERNEL_SMP_H_ */ 72
