From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AE9E3847A; Fri, 10 Nov 2023 09:28:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DhZlWNO/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A6C1C433C8; Fri, 10 Nov 2023 09:28:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699608510; bh=O71kWkjLpRl34q0yTwylpF7QtQRF306pEE+e5Yis+eg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=DhZlWNO/O/GlcCmSNulebkNqJCBcE5IlpGDHxug+wJ86H+p/patK8+fRBqpzzGjaZ d6SvpHoCvd1jfHn0itYAEK/akm7STqjUawTQ2JZfk9hYQA9/TAjtOhrQvPkDcghomr 5kFVtluMH6FzAcpqfx/Y4STvx2lN3e2HW8zTkrkM3qDQ9bdy3wsJYQp/4mPkUiIE1f ZEnVwc6HchoE0JiBE25kzYrFGYEeohmxnnDHR22CC8ILlJX7YmHlR9EQpmT1lwvFq8 uWB5YOP+FAoBaAb6TZBf0qBFLhas93tda9svqEyCKdBaiU2Nm75GqOfA56DsPeewdc jk8hn7oMcLkVA== Received: from johan by theta with local (Exim 4.96.2) (envelope-from ) id 1r1NoP-0002tb-1q; Fri, 10 Nov 2023 10:28:25 +0100 Date: Fri, 10 Nov 2023 10:28:25 +0100 From: Johan Hovold To: Wesley Cheng Cc: Krishna Kurapati PSSNV , Thinh Nguyen , Bjorn Andersson , Greg Kroah-Hartman , Philipp Zabel , Andy Gross , Konrad Dybcio , Rob Herring , Krzysztof Kozlowski , Felipe Balbi , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, quic_pkondeti@quicinc.com, quic_ppratap@quicinc.com, quic_jackp@quicinc.com, ahalaney@redhat.com, quic_shazhuss@quicinc.com Subject: Re: [PATCH v13 05/10] usb: dwc3: qcom: Refactor IRQ handling in QCOM Glue driver Message-ID: References: <14fc724c-bc99-4b5d-9893-3e5eff8895f7@quicinc.com> <04615205-e380-4719-aff1-f32c26004b14@quicinc.com> <2b19b5e2-5eb0-49e0-8c47-8aff3d48f34e@quicinc.com> <50931ba5-132f-3982-e33a-691583e3a71f@quicinc.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <50931ba5-132f-3982-e33a-691583e3a71f@quicinc.com> On Thu, Nov 09, 2023 at 12:25:59PM -0800, Wesley Cheng wrote: > > > > Since the DeviceTree passed to the OS, should describe the hardware to > > > > the OS, and should represent the hardware from the point-of-view of the > > > > OS, adding one interrupt (ctrl_irq[0]) might be sufficient as Linux > > > > would not use the other interrupts. > > > > > > I've only skimmed the virtualisation bits in xHCI spec, but it seems > > > Linux as VMM would still be involved in assigning these interrupts to > > > VMs. > IMO it might be a bit premature to add definitions for how to utilize > secondary interrupters since design wise, there's nothing really too well > defined yet. At least for the XHCI path, we will have a slew of potential > use cases for secondary interrupters, such as USB audio offloading, or for > VMMs, etc... I've only heard mentions about some of them after pushing the > usb audio offloading series, but I don't have much details on it. I tend to agree. > > > This may possibly be something that we can ignore for now, but perhaps > > > someone more familiar with the hardware, like Thinh, can chime in. > > > You need to get into the same mindset when it comes to devicetree. Even > > > if Linux currently does not use an interrupt, like the pwr_event_irq, > > > you should still add it so that when/if someone implements support for > > > it, an older platform using the original dt may also take advantage of > > > it. > > Yeah, I totally agree with this point, but I'm not sure if adding it into > the "interrupts" array is the way to go. It would probably have to change > as support is added. Yes, that in itself would probably not be sufficient and possibly not even correct. > Sorry for jumping in, but just giving my two cents since I'm the one trying > to do the initial push for the support for secondary interrupters :). Appreciate your input. Johan