forked from Minki/linux
8478132a87
This reverts commit 4dd1837d75.
Moving the exports for assembly code into the assembly files breaks
KSYM trimming, but also breaks modversions.
While fixing the KSYM trimming is trivial, fixing modversions brings
us to a technically worse position that we had prior to the above
change:
- We end up with the prototype definitions divorsed from everything
else, which means that adding or removing assembly level ksyms
become more fragile:
* if adding a new assembly ksyms export, a missed prototype in
asm-prototypes.h results in a successful build if no module in
the selected configuration makes use of the symbol.
* when removing a ksyms export, asm-prototypes.h will get forgotten,
with armksyms.c, you'll get a build error if you forget to touch
the file.
- We end up with the same amount of include files and prototypes,
they're just in a header file instead of a .c file with their
exports.
As for lines of code, we don't get much of a size reduction:
(original commit)
47 files changed, 131 insertions(+), 208 deletions(-)
(fix for ksyms trimming)
7 files changed, 18 insertions(+), 5 deletions(-)
(two fixes for modversions)
1 file changed, 34 insertions(+)
3 files changed, 7 insertions(+), 2 deletions(-)
which results in a net total of only 25 lines deleted.
As there does not seem to be much benefit from this change of approach,
revert the change.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
118 lines
3.0 KiB
C
118 lines
3.0 KiB
C
/*
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* Delay loops based on the OpenRISC implementation.
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*
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* Copyright (C) 2012 ARM Limited
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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, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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* Author: Will Deacon <will.deacon@arm.com>
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*/
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#include <linux/clocksource.h>
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#include <linux/delay.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/timex.h>
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/*
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* Default to the loop-based delay implementation.
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*/
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struct arm_delay_ops arm_delay_ops __ro_after_init = {
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.delay = __loop_delay,
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.const_udelay = __loop_const_udelay,
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.udelay = __loop_udelay,
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};
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static const struct delay_timer *delay_timer;
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static bool delay_calibrated;
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static u64 delay_res;
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int read_current_timer(unsigned long *timer_val)
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{
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if (!delay_timer)
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return -ENXIO;
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*timer_val = delay_timer->read_current_timer();
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return 0;
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}
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EXPORT_SYMBOL_GPL(read_current_timer);
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static inline u64 cyc_to_ns(u64 cyc, u32 mult, u32 shift)
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{
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return (cyc * mult) >> shift;
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}
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static void __timer_delay(unsigned long cycles)
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{
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cycles_t start = get_cycles();
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while ((get_cycles() - start) < cycles)
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cpu_relax();
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}
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static void __timer_const_udelay(unsigned long xloops)
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{
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unsigned long long loops = xloops;
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loops *= arm_delay_ops.ticks_per_jiffy;
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__timer_delay(loops >> UDELAY_SHIFT);
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}
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static void __timer_udelay(unsigned long usecs)
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{
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__timer_const_udelay(usecs * UDELAY_MULT);
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}
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void __init register_current_timer_delay(const struct delay_timer *timer)
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{
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u32 new_mult, new_shift;
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u64 res;
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clocks_calc_mult_shift(&new_mult, &new_shift, timer->freq,
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NSEC_PER_SEC, 3600);
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res = cyc_to_ns(1ULL, new_mult, new_shift);
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if (res > 1000) {
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pr_err("Ignoring delay timer %ps, which has insufficient resolution of %lluns\n",
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timer, res);
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return;
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}
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if (!delay_calibrated && (!delay_res || (res < delay_res))) {
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pr_info("Switching to timer-based delay loop, resolution %lluns\n", res);
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delay_timer = timer;
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lpj_fine = timer->freq / HZ;
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delay_res = res;
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/* cpufreq may scale loops_per_jiffy, so keep a private copy */
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arm_delay_ops.ticks_per_jiffy = lpj_fine;
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arm_delay_ops.delay = __timer_delay;
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arm_delay_ops.const_udelay = __timer_const_udelay;
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arm_delay_ops.udelay = __timer_udelay;
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} else {
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pr_info("Ignoring duplicate/late registration of read_current_timer delay\n");
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}
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}
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unsigned long calibrate_delay_is_known(void)
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{
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delay_calibrated = true;
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return lpj_fine;
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}
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void calibration_delay_done(void)
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{
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delay_calibrated = true;
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}
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