 6916b14ea1
			
		
	
	
	6916b14ea1
	
	
	
		
			
			Under arm64, we will calibrate the delay loop statically using a known timer frequency, so delete read_current_timer(), or it will cause compiling issue with allmodconfig. The related error: ERROR: "read_current_timer" [lib/rbtree_test.ko] undefined! ERROR: "read_current_timer" [lib/interval_tree_test.ko] undefined! ERROR: "read_current_timer" [fs/ext4/ext4.ko] undefined! ERROR: "read_current_timer" [crypto/tcrypt.ko] undefined! Signed-off-by: Chen Gang <gang.chen@asianux.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
		
			
				
	
	
		
			86 lines
		
	
	
	
		
			2.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			86 lines
		
	
	
	
		
			2.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Based on arch/arm/kernel/time.c
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|  *
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|  * Copyright (C) 1991, 1992, 1995  Linus Torvalds
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|  * Modifications for ARM (C) 1994-2001 Russell King
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|  * Copyright (C) 2012 ARM Ltd.
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  * GNU General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU General Public License
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|  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
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|  */
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| 
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| #include <linux/export.h>
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| #include <linux/kernel.h>
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| #include <linux/interrupt.h>
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| #include <linux/time.h>
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| #include <linux/init.h>
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| #include <linux/sched.h>
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| #include <linux/smp.h>
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| #include <linux/timex.h>
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| #include <linux/errno.h>
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| #include <linux/profile.h>
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| #include <linux/syscore_ops.h>
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| #include <linux/timer.h>
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| #include <linux/irq.h>
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| #include <linux/delay.h>
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| #include <linux/clocksource.h>
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| 
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| #include <clocksource/arm_arch_timer.h>
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| 
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| #include <asm/thread_info.h>
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| #include <asm/stacktrace.h>
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| 
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| #ifdef CONFIG_SMP
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| unsigned long profile_pc(struct pt_regs *regs)
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| {
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| 	struct stackframe frame;
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| 
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| 	if (!in_lock_functions(regs->pc))
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| 		return regs->pc;
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| 
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| 	frame.fp = regs->regs[29];
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| 	frame.sp = regs->sp;
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| 	frame.pc = regs->pc;
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| 	do {
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| 		int ret = unwind_frame(&frame);
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| 		if (ret < 0)
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| 			return 0;
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| 	} while (in_lock_functions(frame.pc));
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| 
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| 	return frame.pc;
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| }
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| EXPORT_SYMBOL(profile_pc);
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| #endif
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| 
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| static u64 sched_clock_mult __read_mostly;
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| 
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| unsigned long long notrace sched_clock(void)
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| {
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| 	return arch_timer_read_counter() * sched_clock_mult;
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| }
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| 
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| void __init time_init(void)
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| {
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| 	u32 arch_timer_rate;
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| 
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| 	clocksource_of_init();
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| 
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| 	arch_timer_rate = arch_timer_get_rate();
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| 	if (!arch_timer_rate)
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| 		panic("Unable to initialise architected timer.\n");
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| 
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| 	/* Cache the sched_clock multiplier to save a divide in the hot path. */
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| 	sched_clock_mult = NSEC_PER_SEC / arch_timer_rate;
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| 
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| 	/* Calibrate the delay loop directly */
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| 	lpj_fine = arch_timer_rate / HZ;
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| }
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