[PATCH] ARM: i.MX6: add more chip revision support

[Shawn Guo]

On Mon, Jul 21, 2014 at 08:41:45AM +0200, Uwe Kleine-König wrote:
> On Mon, Jul 21, 2014 at 08:35:20AM +0200, Sascha Hauer wrote:
> > On Mon, Jul 21, 2014 at 01:38:11PM +0800, Shawn Guo wrote:
> > > From: Jason Liu <r64343 at freescale.com>
> > > 
> > > Add more revision support for the new i.MX6DQ tap-out (TO1.5).  This
> Is it "tap-out" or "tape-out"? A quick google request suggests the
> latter.

Yes, you're right.

> 
> > > TO1.5 is the Rev 1.3 as documented in i.MX6DQ data sheet, because TO1.3
> > > and TO1.4 are never revealed.
> > 
> > So the chip identifies itself as 1.5 but the data sheet refers to it as
> > 1.3. Is there a way to make that clear somewhere? Otherwise it's really
> > confusing.
> Yeah, from the commit log I would have expected the following patch:
> 
> +	case 5:
> +		revision = IMX_CHIP_REVISION_1_3;
> +		break;
> 
> maybe with a code comment.

I did consider such fix-up when I was trying to submit Jason's patch
from FSL internal tree.  But this TO1.5 numbering has been already used
in a couple of FSL BSP releases.  We do not really want to maintain two
different numbering scheme between FSL BSP and upstream kernel.

> Also, the commit log only mentions i.MX6DQ; I
> wonder about the other imx6 variants. I hope they use the same logic?

This is another reason for that above fix-up may not be good.  This
revision mismatch between register and document is only with i.MX6DQ.
So far, only i.MX6DQ revision goes beyond 1.2, but I'm sure such
mismatch/mistake will not be with other imx6 variants.

Shawn