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34 #include <linux/hash.h>
35 #include <linux/init.h>
37 #include <asm/processor.h>
38 #include <asm/cpufeature.h>
41 static inline u32 crc32_u32(u32 crc, u32 val)
43 #ifdef CONFIG_AS_CRC32
44 asm ("crc32l %1,%0\n" : "+r" (crc) : "rm" (val));
46 asm (".byte 0xf2, 0x0f, 0x38, 0xf1, 0xc1" : "+a" (crc) : "c" (val));
51 static u32 intel_crc4_2_hash(const void *data, u32 len, u32 seed)
53 const u32 *p32 = (const u32 *) data;
56 for (i = 0; i < len / 4; i++)
57 seed = crc32_u32(seed, *p32++);
61 tmp |= *((const u8 *) p32 + 2) << 16;
64 tmp |= *((const u8 *) p32 + 1) << 8;
67 tmp |= *((const u8 *) p32);
68 seed = crc32_u32(seed, tmp);
75 static u32 intel_crc4_2_hash2(const u32 *data, u32 len, u32 seed)
77 const u32 *p32 = (const u32 *) data;
80 for (i = 0; i < len; i++)
81 seed = crc32_u32(seed, *p32++);
86 void __init setup_arch_fast_hash(struct fast_hash_ops *ops)
89 ops->hash = intel_crc4_2_hash;
90 ops->hash2 = intel_crc4_2_hash2;