delay.c
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/*
* linux/arch/m32r/lib/delay.c
*
* Copyright (c) 2002 Hitoshi Yamamoto, Hirokazu Takata
* Copyright (c) 2004 Hirokazu Takata
*/
#include <linux/param.h>
#include <linux/module.h>
#ifdef CONFIG_SMP
#include <linux/sched.h>
#include <asm/current.h>
#include <asm/smp.h>
#endif /* CONFIG_SMP */
#include <asm/processor.h>
void __delay(unsigned long loops)
{
#ifdef CONFIG_ISA_DUAL_ISSUE
__asm__ __volatile__ (
"beqz %0, 2f \n\t"
"addi %0, #-1 \n\t"
" .fillinsn \n\t"
"1: \n\t"
"cmpz %0 || addi %0, #-1 \n\t"
"bc 2f || cmpz %0 \n\t"
"bc 2f || addi %0, #-1 \n\t"
"cmpz %0 || addi %0, #-1 \n\t"
"bc 2f || cmpz %0 \n\t"
"bnc 1b || addi %0, #-1 \n\t"
" .fillinsn \n\t"
"2: \n\t"
: "+r" (loops)
: "r" (0)
: "cbit"
);
#else
__asm__ __volatile__ (
"beqz %0, 2f \n\t"
" .fillinsn \n\t"
"1: \n\t"
"addi %0, #-1 \n\t"
"blez %0, 2f \n\t"
"addi %0, #-1 \n\t"
"blez %0, 2f \n\t"
"addi %0, #-1 \n\t"
"blez %0, 2f \n\t"
"addi %0, #-1 \n\t"
"bgtz %0, 1b \n\t"
" .fillinsn \n\t"
"2: \n\t"
: "+r" (loops)
: "r" (0)
);
#endif
}
void __const_udelay(unsigned long xloops)
{
#if defined(CONFIG_ISA_M32R2) && defined(CONFIG_ISA_DSP_LEVEL2)
/*
* loops [1] = (xloops >> 32) [sec] * loops_per_jiffy [1/jiffy]
* * HZ [jiffy/sec]
* = (xloops >> 32) [sec] * (loops_per_jiffy * HZ) [1/sec]
* = (((xloops * loops_per_jiffy) >> 32) * HZ) [1]
*
* NOTE:
* - '[]' depicts variable's dimension in the above equation.
* - "rac" instruction rounds the accumulator in word size.
*/
__asm__ __volatile__ (
"srli %0, #1 \n\t"
"mulwhi %0, %1 ; a0 \n\t"
"mulwu1 %0, %1 ; a1 \n\t"
"sadd ; a0 += (a1 >> 16) \n\t"
"rac a0, a0, #1 \n\t"
"mvfacmi %0, a0 \n\t"
: "+r" (xloops)
: "r" (current_cpu_data.loops_per_jiffy)
: "a0", "a1"
);
#elif defined(CONFIG_ISA_M32R2) || defined(CONFIG_ISA_M32R)
/*
* u64 ull;
* ull = (u64)xloops * (u64)current_cpu_data.loops_per_jiffy;
* xloops = (ull >> 32);
*/
__asm__ __volatile__ (
"and3 r4, %0, #0xffff \n\t"
"and3 r5, %1, #0xffff \n\t"
"mul r4, r5 \n\t"
"srl3 r6, %0, #16 \n\t"
"srli r4, #16 \n\t"
"mul r5, r6 \n\t"
"add r4, r5 \n\t"
"and3 r5, %0, #0xffff \n\t"
"srl3 r6, %1, #16 \n\t"
"mul r5, r6 \n\t"
"add r4, r5 \n\t"
"srl3 r5, %0, #16 \n\t"
"srli r4, #16 \n\t"
"mul r5, r6 \n\t"
"add r4, r5 \n\t"
"mv %0, r4 \n\t"
: "+r" (xloops)
: "r" (current_cpu_data.loops_per_jiffy)
: "r4", "r5", "r6"
);
#else
#error unknown isa configuration
#endif
__delay(xloops * HZ);
}
void __udelay(unsigned long usecs)
{
__const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
}
void __ndelay(unsigned long nsecs)
{
__const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
}
EXPORT_SYMBOL(__delay);
EXPORT_SYMBOL(__const_udelay);
EXPORT_SYMBOL(__udelay);
EXPORT_SYMBOL(__ndelay);