[patch 03/38] x86/apm: Remove last LATCH usage

Thomas Gleixner
2026-04-10T12:18:53Z

LATCH is a historical leftover and has been replaced with PIT_LATCH in all
other places a decade ago. Replace the last holdout and remove the
definition from jiffies.h.

This allows to remove the otherwise unused CLOCK_TICK_RATE define in the
next step.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
---
arch/x86/kernel/apm_32.c | 4 ++--
include/linux/jiffies.h | 3 ---
2 files changed, 2 insertions(+), 5 deletions(-)

--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -1196,9 +1196,9 @@ static void reinit_timer(void)
/* set the clock to HZ */
outb_p(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
udelay(10);
- outb_p(LATCH & 0xff, PIT_CH0); /* LSB */
+ outb_p(PIT_LATCH & 0xff, PIT_CH0); /* LSB */
udelay(10);
- outb_p(LATCH >> 8, PIT_CH0); /* MSB */
+ outb_p(PIT_LATCH >> 8, PIT_CH0); /* MSB */
udelay(10);
raw_spin_unlock_irqrestore(&i8253_lock, flags);
#endif
--- a/include/linux/jiffies.h
+++ b/include/linux/jiffies.h
@@ -56,9 +56,6 @@
#define SH_DIV(NOM,DEN,LSH) ( (((NOM) / (DEN)) << (LSH)) \
+ ((((NOM) % (DEN)) << (LSH)) + (DEN) / 2) / (DEN))

-/* LATCH is used in the interval timer and ftape setup. */
-#define LATCH ((CLOCK_TICK_RATE + HZ/2) / HZ) /* For divider */
-
extern void register_refined_jiffies(long clock_tick_rate);

/* TICK_USEC is the time between ticks in usec */