1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_WORD_AT_A_TIME_H 3 #define _ASM_WORD_AT_A_TIME_H 4 5 #include <asm/compiler.h> 6 7 /* 8 * word-at-a-time interface for Alpha. 9 */ 10 11 /* 12 * We do not use the word_at_a_time struct on Alpha, but it needs to be 13 * implemented to humour the generic code. 14 */ 15 struct word_at_a_time { 16 const unsigned long unused; 17 }; 18 19 #define WORD_AT_A_TIME_CONSTANTS { 0 } 20 21 /* Return nonzero if val has a zero */ 22 static inline unsigned long has_zero(unsigned long val, unsigned long *bits, const struct word_at_a_time *c) 23 { 24 unsigned long zero_locations = __kernel_cmpbge(0, val); 25 *bits = zero_locations; 26 return zero_locations; 27 } 28 29 static inline unsigned long prep_zero_mask(unsigned long val, unsigned long bits, const struct word_at_a_time *c) 30 { 31 return bits; 32 } 33 34 #define create_zero_mask(bits) (bits) 35 36 static inline unsigned long find_zero(unsigned long bits) 37 { 38 #if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67) 39 /* Simple if have CIX instructions */ 40 return __kernel_cttz(bits); 41 #else 42 unsigned long t1, t2, t3; 43 /* Retain lowest set bit only */ 44 bits &= -bits; 45 /* Binary search for lowest set bit */ 46 t1 = bits & 0xf0; 47 t2 = bits & 0xcc; 48 t3 = bits & 0xaa; 49 if (t1) t1 = 4; 50 if (t2) t2 = 2; 51 if (t3) t3 = 1; 52 return t1 + t2 + t3; 53 #endif 54 } 55 56 #define zero_bytemask(mask) ((2ul << (find_zero(mask) * 8)) - 1) 57 58 #endif /* _ASM_WORD_AT_A_TIME_H */ 59