Files
android/arch/arm/lib/delay-loop.S
threeeye bc1d038eac REVVL 6 Pro kernel bring-up: full working tree snapshot (2026-09-12)
Squashed backup commit (no shallow-clone history issues) of
xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream
commit 9eece662e) plus all fixes applied to get everpal_defconfig building
clean against a modern (GCC 15.2.0) toolchain -- see the previous commit
message on the lineage-23.2 branch (also in this repo history is not
available here since this is a squashed snapshot; full incremental history
lives in the local DL380 checkout and the upstream GitHub remote).

Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
2026-09-12 13:36:46 +00:00

63 lines
1.2 KiB
ArmAsm

/*
* linux/arch/arm/lib/delay.S
*
* Copyright (C) 1995, 1996 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/delay.h>
.text
.LC0: .word loops_per_jiffy
.LC1: .word UDELAY_MULT
/*
* loops = r0 * HZ * loops_per_jiffy / 1000000
*
* r0 <= 2000
* HZ <= 1000
*/
ENTRY(__loop_udelay)
ldr r2, .LC1
mul r0, r2, r0 @ r0 = delay_us * UDELAY_MULT
ENTRY(__loop_const_udelay) @ 0 <= r0 <= 0xfffffaf0
ldr r2, .LC0
ldr r2, [r2]
umull r1, r0, r2, r0 @ r0-r1 = r0 * loops_per_jiffy
adds r1, r1, #0xffffffff @ rounding up ...
adcs r0, r0, r0 @ and right shift by 31
reteq lr
.align 3
@ Delay routine
ENTRY(__loop_delay)
subs r0, r0, #1
#if 0
retls lr
subs r0, r0, #1
retls lr
subs r0, r0, #1
retls lr
subs r0, r0, #1
retls lr
subs r0, r0, #1
retls lr
subs r0, r0, #1
retls lr
subs r0, r0, #1
retls lr
subs r0, r0, #1
#endif
bhi __loop_delay
ret lr
ENDPROC(__loop_udelay)
ENDPROC(__loop_const_udelay)
ENDPROC(__loop_delay)