1 /* 1
2 * This file is subject to the terms and condi
3 * License. See the file "COPYING" in the mai
4 * for more details.
5 *
6 * Copyright (C) 1994 by Waldorf Electronics
7 * Copyright (C) 1995 - 2000, 01, 03 by Ralf B
8 * Copyright (C) 1999, 2000 Silicon Graphics,
9 * Copyright (C) 2007, 2014 Maciej W. Rozycki
10 */
11 #include <linux/delay.h>
12 #include <linux/export.h>
13 #include <linux/param.h>
14 #include <linux/smp.h>
15 #include <linux/stringify.h>
16
17 #include <asm/asm.h>
18 #include <asm/compiler.h>
19
20 #ifndef CONFIG_CPU_DADDI_WORKAROUNDS
21 #define GCC_DADDI_IMM_ASM() "I"
22 #else
23 #define GCC_DADDI_IMM_ASM() "r"
24 #endif
25
26 #ifndef CONFIG_HAVE_PLAT_DELAY
27
28 void __delay(unsigned long loops)
29 {
30 __asm__ __volatile__ (
31 " .set noreorder
32 " .align 3
33 "1: bnez %0, 1b
34 " " __stringify(LONG_SUBU) "
35 " .set reorder
36 : "=r" (loops)
37 : GCC_DADDI_IMM_ASM() (1), "" (loops))
38 }
39 EXPORT_SYMBOL(__delay);
40
41 /*
42 * Division by multiplication: you don't have
43 * loss of precision.
44 *
45 * Use only for very small delays ( < 1 msec).
46 * lookup table, really, as the multiplication
47 * short delays. This is a "reasonable" imple
48 * first constant multiplications gets optimiz
49 * a constant)
50 */
51
52 void __udelay(unsigned long us)
53 {
54 unsigned int lpj = raw_current_cpu_dat
55
56 __delay((us * 0x000010c7ull * HZ * lpj
57 }
58 EXPORT_SYMBOL(__udelay);
59
60 void __ndelay(unsigned long ns)
61 {
62 unsigned int lpj = raw_current_cpu_dat
63
64 __delay((ns * 0x00000005ull * HZ * lpj
65 }
66 EXPORT_SYMBOL(__ndelay);
67
68 #endif
69
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.