1// Copyright 2016 The Fuchsia Authors 2// Copyright (c) 2013 Travis Geiselbrecht 3// 4// Use of this source code is governed by a MIT-style 5// license that can be found in the LICENSE file or at 6// https://opensource.org/licenses/MIT 7 8/* 9 * Global init hook mechanism. Allows code anywhere in the system to define 10 * a init hook that is called at increasing init levels as the system is 11 * initialized. 12 */ 13#include <arch/ops.h> 14#include <lk/init.h> 15 16#include <assert.h> 17#include <debug.h> 18#include <trace.h> 19#include <zircon/compiler.h> 20 21#define LOCAL_TRACE 0 22#define TRACE_INIT (LK_DEBUGLEVEL >= 2) 23#ifndef EARLIEST_TRACE_LEVEL 24#define EARLIEST_TRACE_LEVEL LK_INIT_LEVEL_TARGET_EARLY 25#endif 26 27extern const struct lk_init_struct __start_lk_init[]; 28extern const struct lk_init_struct __stop_lk_init[]; 29 30void lk_init_level(enum lk_init_flags required_flag, uint start_level, uint stop_level) { 31 LTRACEF("flags %#x, start_level %#x, stop_level %#x\n", 32 (uint)required_flag, start_level, stop_level); 33 34 ASSERT(start_level > 0); 35 uint last_called_level = start_level - 1; 36 const struct lk_init_struct* last = NULL; 37 for (;;) { 38 /* search for the lowest uncalled hook to call */ 39 LTRACEF("last %p, last_called_level %#x\n", last, last_called_level); 40 41 const struct lk_init_struct* found = NULL; 42 bool seen_last = false; 43 for (const struct lk_init_struct* ptr = __start_lk_init; ptr != __stop_lk_init; ptr++) { 44 LTRACEF("looking at %p (%s) level %#x, flags %#x, seen_last %d\n", ptr, ptr->name, ptr->level, ptr->flags, seen_last); 45 46 if (ptr == last) 47 seen_last = true; 48 49 /* reject the easy ones */ 50 if (!(ptr->flags & required_flag)) 51 continue; 52 if (ptr->level > stop_level) 53 continue; 54 if (ptr->level < last_called_level) 55 continue; 56 if (found && found->level <= ptr->level) 57 continue; 58 59 /* keep the lowest one we haven't called yet */ 60 if (ptr->level >= start_level && ptr->level > last_called_level) { 61 found = ptr; 62 continue; 63 } 64 65 /* if we're at the same level as the last one we called and we've 66 * already passed over it this time around, we can mark this one 67 * and early terminate the loop. 68 */ 69 if (ptr->level == last_called_level && ptr != last && seen_last) { 70 found = ptr; 71 break; 72 } 73 } 74 75 if (!found) 76 break; 77 78 if (TRACE_INIT) { 79 if (found->level >= EARLIEST_TRACE_LEVEL) { 80 printf("INIT: cpu %u, calling hook %p (%s) at level %#x, flags %#x\n", 81 arch_curr_cpu_num(), found->hook, found->name, found->level, found->flags); 82 } 83 } 84 85 found->hook(found->level); 86 last_called_level = found->level; 87 last = found; 88 } 89} 90