Re: [PATCH v5 2/2] mtd: rawnand: use bit-wise majority to recover the contents of ONFI parameter

From: Boris Brezillon
Date: Tue May 15 2018 - 03:35:46 EST


On Mon, 14 May 2018 20:54:36 +0300
Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:

> On Thu, May 10, 2018 at 3:03 PM, Boris Brezillon
> <boris.brezillon@xxxxxxxxxxx> wrote:
>
> >> +#define GET_BIT(bit, val) (((val) >> (bit)) & 0x01)
> >
> > Not sure we need that macro, see below.
>
> +1. We have too many nice helpers for bit manipulations
> (for_each_set_bit() as an example).
>
>
> > for (k = 0; k < nbufs; k++) {
> > const u8 *srcbuf = srcbufs[j];
> >
> > if (srcbuf[i] & BIT(k))
> > m++;
> > }
>
> ...which is effectively hweightXX().

No it's not.