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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Port on Texas Instruments TMS320C6x architecture
4 *
5 * Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
6 * Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
7 */
8#ifndef _ASM_C6X_DELAY_H
9#define _ASM_C6X_DELAY_H
10
11#include <linux/kernel.h>
12
13extern unsigned int ticks_per_ns_scaled;
14
15static inline void __delay(unsigned long loops)
16{
17 uint32_t tmp;
18
19 /* 6 cycles per loop */
20 asm volatile (" mv .s1 %0,%1\n"
21 "0: [%1] b .s1 0b\n"
22 " add .l1 -6,%0,%0\n"
23 " cmplt .l1 1,%0,%1\n"
24 " nop 3\n"
25 : "+a"(loops), "=A"(tmp));
26}
27
28static inline void _c6x_tickdelay(unsigned int x)
29{
30 uint32_t cnt, endcnt;
31
32 asm volatile (" mvc .s2 TSCL,%0\n"
33 " add .s2x %0,%1,%2\n"
34 " || mvk .l2 1,B0\n"
35 "0: [B0] b .s2 0b\n"
36 " mvc .s2 TSCL,%0\n"
37 " sub .s2 %0,%2,%0\n"
38 " cmpgt .l2 0,%0,B0\n"
39 " nop 2\n"
40 : "=b"(cnt), "+a"(x), "=b"(endcnt) : : "B0");
41}
42
43/* use scaled math to avoid slow division */
44#define C6X_NDELAY_SCALE 10
45
46static inline void _ndelay(unsigned int n)
47{
48 _c6x_tickdelay((ticks_per_ns_scaled * n) >> C6X_NDELAY_SCALE);
49}
50
51static inline void _udelay(unsigned int n)
52{
53 while (n >= 10) {
54 _ndelay(10000);
55 n -= 10;
56 }
57 while (n-- > 0)
58 _ndelay(1000);
59}
60
61#define udelay(x) _udelay((unsigned int)(x))
62#define ndelay(x) _ndelay((unsigned int)(x))
63
64#endif /* _ASM_C6X_DELAY_H */