From 8e4bff4cab0ddac6060645b0715210484d02ff40 Mon Sep 17 00:00:00 2001 From: Yuval Adam <_@yuv.al> Date: Wed, 30 Aug 2017 08:25:59 +0000 Subject: Initial file dump from open source release --- arch/xtensa/include/asm/delay.h | 48 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 arch/xtensa/include/asm/delay.h (limited to 'arch/xtensa/include/asm/delay.h') diff --git a/arch/xtensa/include/asm/delay.h b/arch/xtensa/include/asm/delay.h new file mode 100644 index 00000000..61fc5fae --- /dev/null +++ b/arch/xtensa/include/asm/delay.h @@ -0,0 +1,48 @@ +/* + * include/asm-xtensa/delay.h + * + * 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) 2001 - 2005 Tensilica Inc. + * + */ + +#ifndef _XTENSA_DELAY_H +#define _XTENSA_DELAY_H + +#include +#include + +extern unsigned long loops_per_jiffy; + +static inline void __delay(unsigned long loops) +{ + /* 2 cycles per loop. */ + __asm__ __volatile__ ("1: addi %0, %0, -2; bgeui %0, 2, 1b" + : "=r" (loops) : "0" (loops)); +} + +static __inline__ u32 xtensa_get_ccount(void) +{ + u32 ccount; + asm volatile ("rsr %0, ccount\n" : "=r" (ccount)); + return ccount; +} + +/* For SMP/NUMA systems, change boot_cpu_data to something like + * local_cpu_data->... where local_cpu_data points to the current + * cpu. */ + +static __inline__ void udelay (unsigned long usecs) +{ + unsigned long start = xtensa_get_ccount(); + unsigned long cycles = usecs * (loops_per_jiffy / (1000000UL / HZ)); + + /* Note: all variables are unsigned (can wrap around)! */ + while (((unsigned long)xtensa_get_ccount()) - start < cycles) + ; +} + +#endif -- cgit v1.3.1