forked from Minki/linux
e9cef549c3
Use c0 count register for sched_clock source. This implementation will give high resolution cputime accounting. Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com> Cc: linux-mips@linux-mips.org Cc: macro@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9478/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
45 lines
1021 B
C
45 lines
1021 B
C
/*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 2007 by Ralf Baechle
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*/
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#include <linux/clocksource.h>
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#include <linux/init.h>
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#include <linux/sched_clock.h>
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#include <asm/time.h>
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static cycle_t c0_hpt_read(struct clocksource *cs)
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{
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return read_c0_count();
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}
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static struct clocksource clocksource_mips = {
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.name = "MIPS",
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.read = c0_hpt_read,
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.mask = CLOCKSOURCE_MASK(32),
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.flags = CLOCK_SOURCE_IS_CONTINUOUS,
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};
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static u64 notrace r4k_read_sched_clock(void)
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{
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return read_c0_count();
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}
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int __init init_r4k_clocksource(void)
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{
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if (!cpu_has_counter || !mips_hpt_frequency)
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return -ENXIO;
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/* Calculate a somewhat reasonable rating value */
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clocksource_mips.rating = 200 + mips_hpt_frequency / 10000000;
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clocksource_register_hz(&clocksource_mips, mips_hpt_frequency);
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sched_clock_register(r4k_read_sched_clock, 32, mips_hpt_frequency);
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return 0;
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}
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