diff options
Diffstat (limited to 'arch/arm/lib/delay-loop.S')
| -rw-r--r-- | arch/arm/lib/delay-loop.S | 66 |
1 files changed, 33 insertions, 33 deletions
diff --git a/arch/arm/lib/delay-loop.S b/arch/arm/lib/delay-loop.S index 36b668d8e121..33b08ca1c242 100644 --- a/arch/arm/lib/delay-loop.S +++ b/arch/arm/lib/delay-loop.S @@ -1,67 +1,67 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ /* * 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 <linux/cfi_types.h> #include <asm/assembler.h> #include <asm/delay.h> + +#ifdef CONFIG_ARCH_RPC + .arch armv4 +#endif + .text .LC0: .word loops_per_jiffy .LC1: .word UDELAY_MULT /* + * loops = r0 * HZ * loops_per_jiffy / 1000000 + * * r0 <= 2000 - * lpj <= 0x01ffffff (max. 3355 bogomips) * HZ <= 1000 */ -ENTRY(__loop_udelay) +SYM_TYPED_FUNC_START(__loop_udelay) ldr r2, .LC1 - mul r0, r2, r0 -ENTRY(__loop_const_udelay) @ 0 <= r0 <= 0x7fffff06 - mov r1, #-1 + mul r0, r2, r0 @ r0 = delay_us * UDELAY_MULT + b __loop_const_udelay +SYM_FUNC_END(__loop_udelay) + +SYM_TYPED_FUNC_START(__loop_const_udelay) @ 0 <= r0 <= 0xfffffaf0 ldr r2, .LC0 - ldr r2, [r2] @ max = 0x01ffffff - add r0, r0, r1, lsr #32-14 - mov r0, r0, lsr #14 @ max = 0x0001ffff - add r2, r2, r1, lsr #32-10 - mov r2, r2, lsr #10 @ max = 0x00007fff - mul r0, r2, r0 @ max = 2^32-1 - add r0, r0, r1, lsr #32-6 - movs r0, r0, lsr #6 - moveq pc, lr + 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 + b __loop_delay +SYM_FUNC_END(__loop_const_udelay) -/* - * loops = r0 * HZ * loops_per_jiffy / 1000000 - */ + .align 3 @ Delay routine -ENTRY(__loop_delay) +SYM_TYPED_FUNC_START(__loop_delay) subs r0, r0, #1 #if 0 - movls pc, lr + retls lr subs r0, r0, #1 - movls pc, lr + retls lr subs r0, r0, #1 - movls pc, lr + retls lr subs r0, r0, #1 - movls pc, lr + retls lr subs r0, r0, #1 - movls pc, lr + retls lr subs r0, r0, #1 - movls pc, lr + retls lr subs r0, r0, #1 - movls pc, lr + retls lr subs r0, r0, #1 #endif bhi __loop_delay - mov pc, lr -ENDPROC(__loop_udelay) -ENDPROC(__loop_const_udelay) -ENDPROC(__loop_delay) + ret lr +SYM_FUNC_END(__loop_delay) |