Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 1 | /* |
| 2 | * This file is subject to the terms and conditions of the GNU General Public |
| 3 | * License. See the file "COPYING" in the main directory of this archive |
| 4 | * for more details. |
| 5 | * |
| 6 | * Copyright (C) 1994 by Waldorf Electronics |
| 7 | * Copyright (C) 1995 - 2000, 01, 03 by Ralf Baechle |
| 8 | * Copyright (C) 1999, 2000 Silicon Graphics, Inc. |
Maciej W. Rozycki | 2db4bc3 | 2014-04-01 00:57:28 +0100 | [diff] [blame] | 9 | * Copyright (C) 2007, 2014 Maciej W. Rozycki |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 10 | */ |
Paul Burton | c2c0974 | 2017-08-23 11:17:48 -0700 | [diff] [blame] | 11 | #include <linux/delay.h> |
Paul Gortmaker | 527581b | 2016-08-21 15:58:15 -0400 | [diff] [blame] | 12 | #include <linux/export.h> |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 13 | #include <linux/param.h> |
| 14 | #include <linux/smp.h> |
Maciej W. Rozycki | e496453 | 2014-04-06 21:42:49 +0100 | [diff] [blame] | 15 | #include <linux/stringify.h> |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 16 | |
Maciej W. Rozycki | e496453 | 2014-04-06 21:42:49 +0100 | [diff] [blame] | 17 | #include <asm/asm.h> |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 18 | #include <asm/compiler.h> |
| 19 | #include <asm/war.h> |
| 20 | |
Maciej W. Rozycki | 2db4bc3 | 2014-04-01 00:57:28 +0100 | [diff] [blame] | 21 | #ifndef CONFIG_CPU_DADDI_WORKAROUNDS |
| 22 | #define GCC_DADDI_IMM_ASM() "I" |
| 23 | #else |
| 24 | #define GCC_DADDI_IMM_ASM() "r" |
| 25 | #endif |
| 26 | |
David Daney | 5210edc | 2012-09-28 11:34:10 -0700 | [diff] [blame] | 27 | void __delay(unsigned long loops) |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 28 | { |
| 29 | __asm__ __volatile__ ( |
| 30 | " .set noreorder \n" |
| 31 | " .align 3 \n" |
| 32 | "1: bnez %0, 1b \n" |
Maciej W. Rozycki | e496453 | 2014-04-06 21:42:49 +0100 | [diff] [blame] | 33 | " " __stringify(LONG_SUBU) " %0, %1 \n" |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 34 | " .set reorder \n" |
| 35 | : "=r" (loops) |
Maciej W. Rozycki | 2db4bc3 | 2014-04-01 00:57:28 +0100 | [diff] [blame] | 36 | : GCC_DADDI_IMM_ASM() (1), "0" (loops)); |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 37 | } |
| 38 | EXPORT_SYMBOL(__delay); |
| 39 | |
| 40 | /* |
| 41 | * Division by multiplication: you don't have to worry about |
| 42 | * loss of precision. |
| 43 | * |
Ralf Baechle | 7034228 | 2013-01-22 12:59:30 +0100 | [diff] [blame] | 44 | * Use only for very small delays ( < 1 msec). Should probably use a |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 45 | * lookup table, really, as the multiplications take much too long with |
| 46 | * short delays. This is a "reasonable" implementation, though (and the |
| 47 | * first constant multiplications gets optimized away if the delay is |
| 48 | * a constant) |
| 49 | */ |
| 50 | |
| 51 | void __udelay(unsigned long us) |
| 52 | { |
Ralf Baechle | abe5b41 | 2010-03-10 16:16:04 +0100 | [diff] [blame] | 53 | unsigned int lpj = raw_current_cpu_data.udelay_val; |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 54 | |
Atsushi Nemoto | 3cb3a66 | 2009-06-09 11:12:48 +0900 | [diff] [blame] | 55 | __delay((us * 0x000010c7ull * HZ * lpj) >> 32); |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 56 | } |
| 57 | EXPORT_SYMBOL(__udelay); |
| 58 | |
| 59 | void __ndelay(unsigned long ns) |
| 60 | { |
Ralf Baechle | abe5b41 | 2010-03-10 16:16:04 +0100 | [diff] [blame] | 61 | unsigned int lpj = raw_current_cpu_data.udelay_val; |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 62 | |
Atsushi Nemoto | 3cb3a66 | 2009-06-09 11:12:48 +0900 | [diff] [blame] | 63 | __delay((ns * 0x00000005ull * HZ * lpj) >> 32); |
Ralf Baechle | 5636919 | 2009-02-28 09:44:28 +0000 | [diff] [blame] | 64 | } |
| 65 | EXPORT_SYMBOL(__ndelay); |