On Mon, 2014-03-24 at 21:54 +0100, Marek Vasut wrote: > > + cfg = readl(&pio->cfg[0] + index); > > + cfg &= ~(0xf << offset); > > + cfg |= val << offset; > > + > > + writel(cfg, &pio->cfg[0] + index); > > clrsetbits_le32() here.
I looked at this transform in a few different contexts and one concern I had was that readl and writel have barriers in them (after the read and before the write respectively) while clrsetbits and friends do not. I don't think this will matter for the read/modify/write bit twiddling itself (since there are register dependencies) but I was slightly concerned that the barriers were hiding the lack of explicit barriers which would be required between the various reads/writes. But I think I am probably being overly cautious here and the obvious transformation can be made. Anyone got any thoughts? Ian. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
