On Thu, Nov 29, 2012 at 11:41:50AM -0700, Stephen Warren wrote: > On 11/29/2012 01:44 AM, Thierry Reding wrote: > > On Mon, Nov 26, 2012 at 03:19:08PM +0200, Terje Bergstrom wrote: > > >> diff --git a/drivers/video/tegra/host/host1x/host1x_intr.c > >> b/drivers/video/tegra/host/host1x/host1x_intr.c > > [...] > >> +/* Spacing between sync registers */ +#define REGISTER_STRIDE 4 > > > > Erm... no. The usual way you should be doing this is either make > > the register definitions account for the stride or use accessors > > that apply the stride. You should be doing the latter anyway to > > make accesses. For example: > > > > static inline void host1x_syncpt_writel(struct host1x *host1x, > > unsigned long value, unsigned long offset) { writel(value, > > host1x->regs + SYNCPT_BASE + offset); } > > > > static inline unsigned long host1x_syncpt_readl(struct host1x > > *host1x, unsigned long offset) { return readl(host1x->regs + > > SYNCPT_BASE + offset); } > > > > Alternatively, if you want to pass the register index instead of > > the offset, you can use just multiply the offset in that function: > > > > writel(value, host1x->regs + SYNCPT_BASE + (offset << 2)); > > > > The same can also be done with the non-syncpt registers. > > It seems like reasonable documentation to replace "<< 2" with "* > REGISTER_STRIDE" here. Given that it is a very common pattern, << 2 seems enough documentation to me, but sure, if you prefer to be extra explicit that's fine with me. Thierry
Attachment:
pgpFgzcgSPk70.pgp
Description: PGP signature
_______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel