> From: Tobias Klauser > Sent: 10 August 2015 12:49 > On 2015-08-10 at 11:53:41 +0200, yalin wang <yalin.wang2...@gmail.com> wrote: > > This change to use generic bitrev8() for bmac driver. ... > > @@ -871,7 +860,7 @@ bmac_addhash(struct bmac_data *bp, unsigned char *addr) > > > > if (!(*addr)) return; > > crc = bmac_crc((unsigned short *)addr) & 0x3f; /* Big-endian alert! */
Why not *((u8 *)addr + 1) & 0x3f > > - crc = reverse6[crc]; /* Hyperfast bit-reversing algorithm */ > > + crc = bitrev8((u8)crc); > > No, this won't work. reverse6 works on 6 bit values, while bitrev8 works > on 8bit values, e.g. reverse6[1] = 0x20, while bitrev8(1) = 0x80 You could use bitrev8(n) >> 2. But that is a 'strange' map of a 7-bit value to a 6-bit one. I thought it was more common for ethernet hardware to use the value of the crc register after all 6 bytes of the mac address had been processed. David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/