From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jonathan =?utf-8?Q?Neusch=C3=A4fer?= Subject: Re: [PATCH 1/2] ARM: dts: msm8974: Hook up adsp-pil's xo clock Date: Tue, 21 Feb 2017 17:29:43 +0100 Message-ID: <20170221162943.bpvv3eqf4l2mt74r@latitude> References: <20170215045157.11659-1-j.neuschaefer@gmx.net> <20170220220041.GA3170@hector> <20170221054504.GA24291@minitux> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: <20170221054504.GA24291@minitux> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Bjorn Andersson Cc: Andy Gross , Jonathan Neusch?fer , linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org On Mon, Feb 20, 2017 at 09:45:04PM -0800, Bjorn Andersson wrote: > On Mon 20 Feb 14:00 PST 2017, Andy Gross wrote: > > > On Wed, Feb 15, 2017 at 05:51:56AM +0100, Jonathan Neuschäfer wrote: > > > Without this patch (and with CONFIG_QCOM_ADSP_PIL), I get this error: > > > > > > [ 0.711529] qcom_adsp_pil adsp-pil: failed to get xo clock > > > [ 0.711540] remoteproc remoteproc0: releasing adsp-pil > > > > > > With this patch, adsp-pil can initialize correctly. > > > > > > Signed-off-by: Jonathan Neuschäfer > > Reviewed-by: Bjorn Andersson Thanks! > The ADSP is running off a clock derived from XO, as such a vote for XO > must be held while the ADSP is running. It's possible the all > application CPUs hit idle after launching the ADSP, but before the ADSP > firmware can communicate this need with the RPM, which would result in > the votes hitting 0 and the RPM might gate the XO. > > To prevent this the ADSP remoteproc driver must hold an extra vote with > the RPM until the ADSP signals that it has cast its vote. > > Unfortunately there are some issues with nested probe deferral in the > clock framework, so we can't accurately describe the XO today and as > we're still missing some last pieces of idle mechanism causing above > events we can survive by faking it and using xo_board - for a little > bit longer... Ok, that makes sense. Jonathan -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html