1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Based on arch/arm/kernel/time.c 4 * 5 * Copyright (C) 1991, 1992, 1995 Linus Torvalds 6 * Modifications for ARM (C) 1994-2001 Russell King 7 * Copyright (C) 2012 ARM Ltd. 8 */ 9 10 #include <linux/clockchips.h> 11 #include <linux/export.h> 12 #include <linux/kernel.h> 13 #include <linux/interrupt.h> 14 #include <linux/time.h> 15 #include <linux/init.h> 16 #include <linux/sched.h> 17 #include <linux/smp.h> 18 #include <linux/timex.h> 19 #include <linux/errno.h> 20 #include <linux/profile.h> 21 #include <linux/stacktrace.h> 22 #include <linux/syscore_ops.h> 23 #include <linux/timer.h> 24 #include <linux/irq.h> 25 #include <linux/delay.h> 26 #include <linux/clocksource.h> 27 #include <linux/of_clk.h> 28 #include <linux/acpi.h> 29 30 #include <clocksource/arm_arch_timer.h> 31 32 #include <asm/thread_info.h> 33 #include <asm/paravirt.h> 34 35 static bool profile_pc_cb(void *arg, unsigned long pc) 36 { 37 unsigned long *prof_pc = arg; 38 39 if (in_lock_functions(pc)) 40 return true; 41 *prof_pc = pc; 42 return false; 43 } 44 45 unsigned long profile_pc(struct pt_regs *regs) 46 { 47 unsigned long prof_pc = 0; 48 49 arch_stack_walk(profile_pc_cb, &prof_pc, current, regs); 50 51 return prof_pc; 52 } 53 EXPORT_SYMBOL(profile_pc); 54 55 void __init time_init(void) 56 { 57 u32 arch_timer_rate; 58 59 of_clk_init(NULL); 60 timer_probe(); 61 62 tick_setup_hrtimer_broadcast(); 63 64 arch_timer_rate = arch_timer_get_rate(); 65 if (!arch_timer_rate) 66 panic("Unable to initialise architected timer.\n"); 67 68 /* Calibrate the delay loop directly */ 69 lpj_fine = arch_timer_rate / HZ; 70 71 pv_time_init(); 72 } 73