| /* |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| * |
| * Copyright (C) 1994 by Waldorf Electronics |
| * Copyright (C) 1995 - 2000, 01, 03 by Ralf Baechle |
| * Copyright (C) 1999, 2000 Silicon Graphics, Inc. |
| * Copyright (C) 2007, 2014 Maciej W. Rozycki |
| */ |
| #include <linux/delay.h> |
| #include <linux/export.h> |
| #include <linux/param.h> |
| #include <linux/smp.h> |
| #include <linux/stringify.h> |
| |
| #include <asm/asm.h> |
| #include <asm/compiler.h> |
| #include <asm/war.h> |
| |
| #ifndef CONFIG_CPU_DADDI_WORKAROUNDS |
| #define GCC_DADDI_IMM_ASM() "I" |
| #else |
| #define GCC_DADDI_IMM_ASM() "r" |
| #endif |
| |
| void __delay(unsigned long loops) |
| { |
| __asm__ __volatile__ ( |
| " .set noreorder \n" |
| " .align 3 \n" |
| "1: bnez %0, 1b \n" |
| " " __stringify(LONG_SUBU) " %0, %1 \n" |
| " .set reorder \n" |
| : "=r" (loops) |
| : GCC_DADDI_IMM_ASM() (1), "0" (loops)); |
| } |
| EXPORT_SYMBOL(__delay); |
| |
| /* |
| * Division by multiplication: you don't have to worry about |
| * loss of precision. |
| * |
| * Use only for very small delays ( < 1 msec). Should probably use a |
| * lookup table, really, as the multiplications take much too long with |
| * short delays. This is a "reasonable" implementation, though (and the |
| * first constant multiplications gets optimized away if the delay is |
| * a constant) |
| */ |
| |
| void __udelay(unsigned long us) |
| { |
| unsigned int lpj = raw_current_cpu_data.udelay_val; |
| |
| __delay((us * 0x000010c7ull * HZ * lpj) >> 32); |
| } |
| EXPORT_SYMBOL(__udelay); |
| |
| void __ndelay(unsigned long ns) |
| { |
| unsigned int lpj = raw_current_cpu_data.udelay_val; |
| |
| __delay((ns * 0x00000005ull * HZ * lpj) >> 32); |
| } |
| EXPORT_SYMBOL(__ndelay); |