From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sjoerd Simons Subject: Re: [5/5] ARM: tegra: jetson-tk1: enable GK20A GPU Date: Thu, 25 Sep 2014 20:10:31 +0200 Message-ID: <1411668631.24948.9.camel@luon.net> References: <1400491450-19223-6-git-send-email-acourbot@nvidia.com> <20140925132717.GA13579@dusk.luon.net> <54243931.6050804@wwwdotorg.org> <20140925164109.GA30382@ulmo> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: <20140925164109.GA30382@ulmo> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Thierry Reding Cc: Stephen Warren , Alexandre Courbot , Ben Skeggs , nouveau-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, gnurou-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org List-Id: linux-tegra@vger.kernel.org On Thu, 2014-09-25 at 18:41 +0200, Thierry Reding wrote: > On Thu, Sep 25, 2014 at 09:48:01AM -0600, Stephen Warren wrote: > > On 09/25/2014 07:27 AM, Sjoerd Simons wrote: > > >Playing a bit with todays linux-next on my jetson, it seems this patch is > > >still required for enabling the GPU. Is there anything blocking it (firmware > > >not available yet in liux-firmware?) > > > > I think initially I was waiting for the DRM patch "drm/nouvea: support for > > probing platform devices" to be applied, but it looks like that's been > > applied already, so only patches 4 and 5 in this series are still > > outstanding. > > > > Alex, wasn't there also some issue where the VPR register had to be > > programmed, and if it wasn't there'd be a hang when the GPU registers were > > touched? If we've added code to Nouveau/tegradrm to detect that and avoid > > the problem, then I guess we can commit these last two patches for 3.19. A > > resend after the 3.18 merge window might help. > > A patch that programs VPR was merged into U-Boot (though I don't think > it's made it into master yet). Assuming you're talking about "ARM: tegra: Disable VPR",that has landed in u-boot master and released as part of v2014.10-rc2 [0] > I'm not sure we can reasonably check for > that in Nouveau, given that the register is somewhere completely > unrelated. In fact I think the U-Boot patch was triggered by some > discussion about how to solve this and it was decided that it shouldn't > be done in the kernel, but U-Boot should set it up. > > That said, perhaps one solution would be to make U-Boot enable the gk20a > device if it's set up the VPR and disable it otherwise? I guess in that case the vdd-supply should still be added to the dts with u-boot toggling the status field of the node? 0: http://git.denx.de/?p=u-boot.git;a=commit;h=df3443dfa449ad02bef8ddf6e2c90a6fd9394fc9 -- Sjoerd Simons