[U-Boot] [PATCH 1/2] arm: imx6: Add DDR3 calibration code for MX6 Q/D/DL

From: Marek Vasut <marex@denx.de>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 1/2] arm: imx6: Add DDR3 calibration code for MX6 Q/D/DL
Date: Thu, 14 Jan 2016 04:06:17 +0100	[thread overview]
Message-ID: <201601140406.17647.marex@denx.de> (raw)
In-Reply-To: <56970D6B.1010600@nelint.com>

On Thursday, January 14, 2016 at 03:52:27 AM, Eric Nelson wrote:
> On 01/13/2016 07:50 PM, Marek Vasut wrote:
> > On Thursday, January 14, 2016 at 03:37:09 AM, Eric Nelson wrote:
> >> Hi Marek,
> > 
> > Hi!
> > 
> >> On 01/13/2016 07:10 PM, Marek Vasut wrote:
> >>> On Tuesday, December 22, 2015 at 04:37:12 PM, Eric Nelson wrote:
> >>>> Hi Marek,
> >>> 
> >>> Hi Eric,
> >>> 
> >>> [..]
> >>> 
> >>>>>> This should also have parameters of mx6_ddr_sysinfo (input) and
> >>>>>> mx6_mmdc_calibration (output), at least for sysinfo->dsize
> >>>>> 
> >>>>> Would it be possible for you to send a subsequent patch(set)? I would
> >>>>> like to have this code as a working base , since I tested this
> >>>>> thoroughly. If I apply all of your changes, it would basically mean
> >>>>> almost complete rewrite of the code and that would disallow me bisect
> >>>>> possible bugs introduced by these changes.
> >>>> 
> >>>> I think that's a bit of overstatement, but I'm okay sending patches
> >>>> in principle.
> >>>> 
> >>>> I do think that at least the test for calibration failure should be
> >>>> fixed before your patch is applied.
> >>>> 
> >>>> This also has the benefit of allowing discussion about each of
> >>>> my points individually instead of in one e-mail thread.
> >>> 
> >>> I have to admit I'm a bit lost in this. What do you say we ask Stefano
> >>> to apply this so people can start fiddling with it. I'd also like to
> >>> see the patches for MX6SX and your fixes (if you feel like it).
> >> 
> >> I'm okay with that.
> >> 
> >> I was hoping to check out the error handling code but unfortunately,
> >> the boards I have that are supporting SPL are all either i.MX6DL,
> >> i.MX6S, or i.MX6SL.
> >> 
> >> You should be able to force a failure by setting WALAT and/or RALAT
> >> to extreme values and see how the DDR controller responds.
> > 
> > I only have Q ;-) The DDR calibration code _should_ work on DL though.
> 
> It at least needs a change to some #ifdefs:
> 
> +#if defined(CONFIG_MX6QDL) || defined(CONFIG_MX6Q) || defined(CONFIG_MX6D)

And then you can test it ;-) Have fun, I'm looking forward to improvements :)

Best regards,
Marek Vasut