1/*
2 *  Port on Texas Instruments TMS320C6x architecture
3 *
4 *  Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
5 *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
6 *
7 *  This program is free software; you can redistribute it and/or modify
8 *  it under the terms of the GNU General Public License version 2 as
9 *  published by the Free Software Foundation.
10 */
11#ifndef _ASM_C6X_DELAY_H
12#define _ASM_C6X_DELAY_H
13
14#include <linux/kernel.h>
15
16extern unsigned int ticks_per_ns_scaled;
17
18static inline void __delay(unsigned long loops)
19{
20	uint32_t tmp;
21
22	/* 6 cycles per loop */
23	asm volatile ("        mv    .s1  %0,%1\n"
24		      "0: [%1] b     .s1  0b\n"
25		      "        add   .l1  -6,%0,%0\n"
26		      "        cmplt .l1  1,%0,%1\n"
27		      "        nop   3\n"
28		      : "+a"(loops), "=A"(tmp));
29}
30
31static inline void _c6x_tickdelay(unsigned int x)
32{
33	uint32_t cnt, endcnt;
34
35	asm volatile ("        mvc   .s2   TSCL,%0\n"
36		      "        add   .s2x  %0,%1,%2\n"
37		      " ||     mvk   .l2   1,B0\n"
38		      "0: [B0] b     .s2   0b\n"
39		      "        mvc   .s2   TSCL,%0\n"
40		      "        sub   .s2   %0,%2,%0\n"
41		      "        cmpgt .l2   0,%0,B0\n"
42		      "        nop   2\n"
43		      : "=b"(cnt), "+a"(x), "=b"(endcnt) : : "B0");
44}
45
46/* use scaled math to avoid slow division */
47#define C6X_NDELAY_SCALE 10
48
49static inline void _ndelay(unsigned int n)
50{
51	_c6x_tickdelay((ticks_per_ns_scaled * n) >> C6X_NDELAY_SCALE);
52}
53
54static inline void _udelay(unsigned int n)
55{
56	while (n >= 10) {
57		_ndelay(10000);
58		n -= 10;
59	}
60	while (n-- > 0)
61		_ndelay(1000);
62}
63
64#define udelay(x) _udelay((unsigned int)(x))
65#define ndelay(x) _ndelay((unsigned int)(x))
66
67#endif /* _ASM_C6X_DELAY_H */
68