[RFC PATCH v9 14/15] arm64/delay: move some constants out to a separate header
Ankur Arora
ankur.a.arora at oracle.com
Thu Nov 7 11:08:17 PST 2024
Moves some constants and functions related to xloops, cycles computation
out to a new header.
No functional change.
Signed-off-by: Ankur Arora <ankur.a.arora at oracle.com>
---
arch/arm64/include/asm/delay-const.h | 25 +++++++++++++++++++++++++
arch/arm64/lib/delay.c | 13 +++----------
2 files changed, 28 insertions(+), 10 deletions(-)
create mode 100644 arch/arm64/include/asm/delay-const.h
diff --git a/arch/arm64/include/asm/delay-const.h b/arch/arm64/include/asm/delay-const.h
new file mode 100644
index 000000000000..63fb5fc24a90
--- /dev/null
+++ b/arch/arm64/include/asm/delay-const.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _ASM_DELAY_CONST_H
+#define _ASM_DELAY_CONST_H
+
+#include <asm/param.h> /* For HZ */
+
+/* 2**32 / 1000000 (rounded up) */
+#define __usecs_to_xloops_mult 0x10C7UL
+
+/* 2**32 / 1000000000 (rounded up) */
+#define __nsecs_to_xloops_mult 0x5UL
+
+extern unsigned long loops_per_jiffy;
+static inline unsigned long xloops_to_cycles(unsigned long xloops)
+{
+ return (xloops * loops_per_jiffy * HZ) >> 32;
+}
+
+#define USECS_TO_CYCLES(time_usecs) \
+ xloops_to_cycles((time_usecs) * __usecs_to_xloops_mult)
+
+#define NSECS_TO_CYCLES(time_nsecs) \
+ xloops_to_cycles((time_nsecs) * __nsecs_to_xloops_mult)
+
+#endif /* _ASM_DELAY_CONST_H */
diff --git a/arch/arm64/lib/delay.c b/arch/arm64/lib/delay.c
index cb2062e7e234..511b5597e2a5 100644
--- a/arch/arm64/lib/delay.c
+++ b/arch/arm64/lib/delay.c
@@ -12,17 +12,10 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/timex.h>
+#include <asm/delay-const.h>
#include <clocksource/arm_arch_timer.h>
-#define USECS_TO_CYCLES(time_usecs) \
- xloops_to_cycles((time_usecs) * 0x10C7UL)
-
-static inline unsigned long xloops_to_cycles(unsigned long xloops)
-{
- return (xloops * loops_per_jiffy * HZ) >> 32;
-}
-
void __delay(unsigned long cycles)
{
cycles_t start = get_cycles();
@@ -58,12 +51,12 @@ EXPORT_SYMBOL(__const_udelay);
void __udelay(unsigned long usecs)
{
- __const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
+ __const_udelay(usecs * __usecs_to_xloops_mult);
}
EXPORT_SYMBOL(__udelay);
void __ndelay(unsigned long nsecs)
{
- __const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
+ __const_udelay(nsecs * __nsecs_to_xloops_mult);
}
EXPORT_SYMBOL(__ndelay);
--
2.43.5
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