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/syscore_ops.h> 22 #include <linux/timer.h> 23 #include <linux/irq.h> 24 #include <linux/delay.h> 25 #include <linux/clocksource.h> 26 #include <linux/clk-provider.h> 27 #include <linux/acpi.h> 28 29 #include <clocksource/arm_arch_timer.h> 30 31 #include <asm/thread_info.h> 32 #include <asm/stacktrace.h> 33 34 unsigned long profile_pc(struct pt_regs *regs) 35 { 36 struct stackframe frame; 37 38 if (!in_lock_functions(regs->pc)) 39 return regs->pc; 40 41 start_backtrace(&frame, regs->regs[29], regs->pc); 42 43 do { 44 int ret = unwind_frame(NULL, &frame); 45 if (ret < 0) 46 return 0; 47 } while (in_lock_functions(frame.pc)); 48 49 return frame.pc; 50 } 51 EXPORT_SYMBOL(profile_pc); 52 53 void __init time_init(void) 54 { 55 u32 arch_timer_rate; 56 57 of_clk_init(NULL); 58 timer_probe(); 59 60 tick_setup_hrtimer_broadcast(); 61 62 arch_timer_rate = arch_timer_get_rate(); 63 if (!arch_timer_rate) 64 panic("Unable to initialise architected timer.\n"); 65 66 /* Calibrate the delay loop directly */ 67 lpj_fine = arch_timer_rate / HZ; 68 } 69