59 lines
1.3 KiB
C
59 lines
1.3 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_WORD_AT_A_TIME_H
|
|
#define _ASM_WORD_AT_A_TIME_H
|
|
|
|
#include <asm/compiler.h>
|
|
|
|
/*
|
|
* word-at-a-time interface for Alpha.
|
|
*/
|
|
|
|
/*
|
|
* We do not use the word_at_a_time struct on Alpha, but it needs to be
|
|
* implemented to humour the generic code.
|
|
*/
|
|
struct word_at_a_time {
|
|
const unsigned long unused;
|
|
};
|
|
|
|
#define WORD_AT_A_TIME_CONSTANTS { 0 }
|
|
|
|
/* Return nonzero if val has a zero */
|
|
static inline unsigned long has_zero(unsigned long val, unsigned long *bits, const struct word_at_a_time *c)
|
|
{
|
|
unsigned long zero_locations = __kernel_cmpbge(0, val);
|
|
*bits = zero_locations;
|
|
return zero_locations;
|
|
}
|
|
|
|
static inline unsigned long prep_zero_mask(unsigned long val, unsigned long bits, const struct word_at_a_time *c)
|
|
{
|
|
return bits;
|
|
}
|
|
|
|
#define create_zero_mask(bits) (bits)
|
|
|
|
static inline unsigned long find_zero(unsigned long bits)
|
|
{
|
|
#if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
|
|
/* Simple if have CIX instructions */
|
|
return __kernel_cttz(bits);
|
|
#else
|
|
unsigned long t1, t2, t3;
|
|
/* Retain lowest set bit only */
|
|
bits &= -bits;
|
|
/* Binary search for lowest set bit */
|
|
t1 = bits & 0xf0;
|
|
t2 = bits & 0xcc;
|
|
t3 = bits & 0xaa;
|
|
if (t1) t1 = 4;
|
|
if (t2) t2 = 2;
|
|
if (t3) t3 = 1;
|
|
return t1 + t2 + t3;
|
|
#endif
|
|
}
|
|
|
|
#define zero_bytemask(mask) ((2ul << (find_zero(mask) * 8)) - 1)
|
|
|
|
#endif /* _ASM_WORD_AT_A_TIME_H */
|