From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH 09/11] tegrarcm: Add support for odmdata command Date: Mon, 16 Sep 2013 15:26:48 -0600 Message-ID: <52377798.5000209@wwwdotorg.org> References: <1378757761-20939-1-git-send-email-amartin@nvidia.com> <1378757761-20939-10-git-send-email-amartin@nvidia.com> <522E436F.90402@wwwdotorg.org> <20130911211228.GC29868@badger> <5230DD8F.4030703@wwwdotorg.org> <20130916202851.GA1663@badger> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130916202851.GA1663@badger> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Allen Martin Cc: "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-tegra@vger.kernel.org On 09/16/2013 02:28 PM, Allen Martin wrote: > On Wed, Sep 11, 2013 at 02:15:59PM -0700, Stephen Warren wrote: >> On 09/11/2013 03:12 PM, Allen Martin wrote: >>> On Mon, Sep 09, 2013 at 02:53:51PM -0700, Stephen Warren wrote: >>>> On 09/09/2013 02:15 PM, Allen Martin wrote: >>>>> Add command "--odmdata" to pass odmdata down to the miniloader. This >>>>> is used by the miniloader for things such as UART init and RAM sizing. >>>>> It is normally not needed and is really only useful for miniloader >>>>> debugging. >>>> >>>> Does the miniloader put it into the BCT in IRAM so that the bootloader >>>> can also read it? If suppose we expect the correct ODMDATA to be already >>>> included in the BCT that tegrarcm sends though, so the bootloader >>>> already sees the correct value. >>> >>> Yes, miniloader will update the BCT with the new value if you send >>> this command after downloading a BCT. Really the only thing I'm using >>> this for is the side effect inside miniloader that causes it to >>> reinitialize the UART with the new odmdata value. For some reason >>> when you donwload the BCT, miniloader does not do that, and when you >>> boot in recovery mode there's no initial BCT so UART never gets >>> initialized in miniloader and you get no debug prints. >> >> Oh, I wasn't aware that the miniloader ever initialized the UART. Debug >> prints from what? The miniloader itself, or what it loads (which I think >> should be initializing the UART from scratch anyway, since I assume the >> boot ROM doesn't do it for the regular boot path either). > > Yes, debugging the miniloader. I loaded a debug version of the > miniloader during venice2 bringup to determine why it was failing and > added this command so I could see the error messages from it. It may > only be useful to me, so I can yank it from the series if you don't > think it's useful for inclusion in the upstream repository. It might not be a bad idea to remove it then; having it around will just encourage people to use it rather than setting the ODMDATA correctly in the BCT. If/when we get an OSS miniloader replacement, we can always think about adding it back, although then I'd argue that the UART should be initialized as a side-effect of downloading/activating the BCT anyway, so you still wouldn't need the command.