Brooklyn/arch/s390/lib/delay.c
crowetic a94b3d14aa Brooklyn+ (PLUS) changes
Changes included (and more):

1. Dynamic RAM merge

2. Real-time page scan and allocation

3. Cache compression

4. Real-time IRQ checks

5. Dynamic I/O allocation for Java heap

6. Java page migration

7. Contiguous memory allocation

8. Idle pages tracking

9. Per CPU RAM usage tracking

10. ARM NEON scalar multiplication library

11. NEON/ARMv8 crypto extensions

12. NEON SHA, Blake, RIPEMD crypto extensions

13. Parallel NEON crypto engine for multi-algo based CPU stress reduction
2022-05-12 10:47:00 -07:00

49 lines
1.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Precise Delay Loops for S390
*
* Copyright IBM Corp. 1999, 2008
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
*/
#include <linux/processor.h>
#include <linux/delay.h>
#include <asm/div64.h>
#include <asm/timex.h>
void __delay(unsigned long loops)
{
/*
* To end the bloody studid and useless discussion about the
* BogoMips number I took the liberty to define the __delay
* function in a way that that resulting BogoMips number will
* yield the megahertz number of the cpu. The important function
* is udelay and that is done using the tod clock. -- martin.
*/
asm volatile("0: brct %0,0b" : : "d" ((loops/2) + 1));
}
EXPORT_SYMBOL(__delay);
static void delay_loop(unsigned long delta)
{
unsigned long end;
end = get_tod_clock_monotonic() + delta;
while (!tod_after(get_tod_clock_monotonic(), end))
cpu_relax();
}
void __udelay(unsigned long usecs)
{
delay_loop(usecs << 12);
}
EXPORT_SYMBOL(__udelay);
void __ndelay(unsigned long nsecs)
{
nsecs <<= 9;
do_div(nsecs, 125);
delay_loop(nsecs);
}
EXPORT_SYMBOL(__ndelay);