From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 22D77C3DA40 for ; Fri, 5 Jul 2024 18:31:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=k7ilQYq+lc/EGL+S3GheZNonRRIlRWvuqt1EVV8+fas=; b=Wv6SRv2O3mE2Pq1pmiC+rJnQK9 4/yfwyY4VEWHahkGEnBH/HRP9LmNd7fvNsHNk5QwPrUe4NEobAc/6GMpQ2trKb8eSv1345PuPwgP3 bNJ27nbVvl3JT3BLCkM98Bu8zL3ZcUyyWrPwHdHbCQQdob7dsp9mTK1mSxBDhKwjg8tNbI/1tBOVK CdDHAO6ZknxJ8kgpeSDIGjsuh3D3zQWTi93OYyueQGZ+rmz5V85b6U4qvGTY2Pl9ziq8WM15Xu4ln keVM3ETpWpygnJZ6Wzs2SZPcvZFv43IF8Ct/+N2n3HOtAaNAYXBKpOUme0BzPAZAYekWfoyoVDGa2 ED5RyMrA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sPniA-0000000GdlP-2XKs; Fri, 05 Jul 2024 18:31:10 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sPmXj-0000000GWYy-0dfm for linux-arm-kernel@lists.infradead.org; Fri, 05 Jul 2024 17:16:20 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6356BDA7; Fri, 5 Jul 2024 10:16:41 -0700 (PDT) Received: from [172.27.42.201] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 040D93F762; Fri, 5 Jul 2024 10:16:16 -0700 (PDT) Message-ID: <38e46b44-6248-45e8-bdf9-66008a2fe290@arm.com> Date: Fri, 5 Jul 2024 12:16:14 -0500 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 09/11] usb: dwc2: Skip clock gating on Broadcom SoCs Content-Language: en-US To: Stefan Wahren , Lukas Wunner Cc: Florian Fainelli , Minas Harutyunyan , Greg Kroah-Hartman , Ray Jui , Scott Branden , Maxime Ripard , Thomas Gleixner , Jassi Brar , Ulf Hansson , Jiri Slaby , Dave Stevenson , Maarten Lankhorst , Thomas Zimmermann , David Airlie , Daniel Vetter , Peter Robinson , dri-devel@lists.freedesktop.org, bcm-kernel-feedback-list@broadcom.com, linux-pm@vger.kernel.org, linux-serial@vger.kernel.org, linux-usb@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel-list@raspberrypi.com References: <20240630153652.318882-1-wahrenst@gmx.net> <20240630153652.318882-10-wahrenst@gmx.net> <95762956-b46a-4dfa-b22f-bccbfa39558d@broadcom.com> <4502d826-d80c-4a98-a889-da7badfa698e@gmx.net> <43fa421c-5e5b-40a6-a546-d80e753586e3@gmx.net> From: Jeremy Linton In-Reply-To: <43fa421c-5e5b-40a6-a546-d80e753586e3@gmx.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240705_101619_295319_F535E37E X-CRM114-Status: GOOD ( 16.29 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On 7/5/24 10:21, Stefan Wahren wrote: > Hi Jeremy, > > Am 05.07.24 um 17:03 schrieb Lukas Wunner: >> On Fri, Jul 05, 2024 at 12:22:33PM +0200, Stefan Wahren wrote: >>> Am 05.07.24 um 10:48 schrieb Lukas Wunner: >>>> The real question is whether BCM2848 platforms likewise cannot disable >>>> the clock of the dwc2 controller or whether this is specific to the >>>> BCM2835.  Right now dwc2_set_bcm_params() is applied to both the >>>> BCM2848 and BCM2835.  If the BCM2848 behaves differently in this >>>> regard, we'd have to duplicate dwc2_set_bcm_params() for the BCM2835. >>>  From my understand BCM2848 refers to the same SoC, but the ACPI >>> implementation uses a different ID [2]. So I think this is safe. >>> [2] - >>> https://patches.linaro.org/project/linux-usb/patch/20210413215834.3126447-2-jeremy.linton@arm.com/ >> Careful there, the patch vaguely says... >> >>      With that added and identified as "BCM2848", >>      an id in use by other OSs for this device, the dw2 >>      controller on the BCM2711 will work. >> >> ...which sounds like they copy-pasted the BCM2848 id from somewhere else. >> I would assume that BCM2848 is really a different SoC and not just >> a different name for the BCM2835, but hopefully BroadCom folks will >> be able to confirm or deny this (and thus the necessity of the quirk >> on BCM2848 and not just on BCM2835). > could you please clarify this situation? This id comes from the edk2-platforms ACPI tables and is currently used by both the rpi3 and rpi4, and AFAIK nothing else as the rpi5-dev work is currently only exposing XHCI. The ID is strictly the USB controller not the SoC. Its a bit confusingly named, but something we inherited from the much older windows/edk2 port, where it appears that the peripheral HID's were just picked in numerical order. [0] https://github.com/tianocore/edk2-platforms/blob/12f68d29abdc9d703f67bd743fdec23ebb1e966e/Platform/RaspberryPi/AcpiTables/GpuDevs.asl#L15