| /* SPDX-License-Identifier: GPL-2.0-only */ |
| * linux/arch/unicore32/lib/delay.S |
| * Code specific to PKUnity SoC and UniCore ISA |
| * Copyright (C) 2001-2010 GUAN Xue-tao |
| #include <linux/linkage.h> |
| #include <asm/assembler.h> |
| .LC0: .word loops_per_jiffy |
| .LC1: .word (2199023*HZ)>>11 |
| * lpj <= 0x01ffffff (max. 3355 bogomips) |
| ENTRY(__const_udelay) @ 0 <= r0 <= 0x7fffff06 |
| ldw r2, [r2] @ max = 0x01ffffff |
| mov r0, r0 >> #14 @ max = 0x0001ffff |
| mov r2, r2 >> #10 @ max = 0x00007fff |
| mul r0, r2, r0 @ max = 2^32-1 |
| * loops = r0 * HZ * loops_per_jiffy / 1000000 |
| * Oh, if only we had a cycle counter... |