From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [PATCH 1/1] arm64: dts: qcom: Add Lenovo Yoga C630 Date: Tue, 3 Sep 2019 07:21:53 +0100 Message-ID: <20190903062153.GD26880@dell> References: <20190902132400.14084-1-lee.jones@linaro.org> <20190903054451.GV6167@minitux> <20190903062040.GC26880@dell> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: <20190903062040.GC26880@dell> Sender: linux-kernel-owner@vger.kernel.org To: Bjorn Andersson Cc: agross@kernel.org, robh+dt@kernel.org, mark.rutland@arm.com, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org List-Id: devicetree@vger.kernel.org On Tue, 03 Sep 2019, Lee Jones wrote: > On Mon, 02 Sep 2019, Bjorn Andersson wrote: > > > On Mon 02 Sep 06:24 PDT 2019, Lee Jones wrote: > > > > > From: Bjorn Andersson > > > > > > The Lenovo Yoga C630 is built on the SDM850 from Qualcomm, but this seem > > > to be similar enough to the SDM845 that we can reuse the sdm845.dtsi. > > > > > > Supported by this patch is: keyboard, battery monitoring, UFS storage, > > > USB host and Bluetooth. > > > > Applied this to next-20190829 and booted it, got a little bit of EFI FB, > > then the screen goes blank and after a while I'm back in GRUB. > > > > I've not been able to figure out what's causing this though. > > Probably DMA. There is still an issue in the COM GENI Serial Engine > Driver which reboots the system when a DMA transaction is initiated. > > However, with a workaround patch applied to the Serial Engine driver > (drivers/soc/qcom/qcom-geni-se.c) this DTS has no issue booting the > system. > > We have ~12 weeks to either fix or elegantly work around the Serial > Engine issue. IMHO is makes no sense to hold back this enablement > patch (which cannot go in via the -rcs) for something which is likely > to be fixed and applied during v3.4-rcX. NB: If you're worried about other entities thinking the platform boots fault free due to this DTS patch being applied, I would suggest we place a little "NB:" note in the changelog to explain the situation. -- Lee Jones [李琼斯] Linaro Services Technical Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog