From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outbound3.mail.transip.nl (outbound3.mail.transip.nl [136.144.136.12]) (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 F2E2B30E82C; Fri, 19 Jun 2026 08:10:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=136.144.136.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781856659; cv=none; b=ujOMyWZI5xPE3fcZn/YlhEURole5KEzbmv8pImA/oe5zbpjlBcOqHxIMMDt8BP5NTyFayOhSQ5+/YwIcpQVQfw5vXUgZZSLSGU+BNxAfJE72uJ8KvdJmdtjNTpsoHBhAbluAyFTNFqqp+qjY21flhBPev3dF4vZtkcXbdtYIXQ8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781856659; c=relaxed/simple; bh=BpBGkCSu7+PzRSqdV+sqhQ62LthPAHGqeO4TeM6FeFU=; h=MIME-Version:Date:From:To:Cc:Subject:In-Reply-To:References: Message-ID:Content-Type; b=lmyOzXdwsy6UZqnyC5psKIUoTVDs2GndONyx1sL8DyXEg70gVEau1z0H2eYcoM3dN88Zw88c/UBDVw/2qhAj3Px+uHIHjUvMUy+axjZIyUh39cXzJiTuxwfTxV5WvyXfv5i/F/pFANS77mzI3/ckl2ENMjCj14Y2kNDPAUX5zuk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=herrie.org; spf=pass smtp.mailfrom=herrie.org; dkim=pass (2048-bit key) header.d=herrie.org header.i=@herrie.org header.b=VfZbndLn; arc=none smtp.client-ip=136.144.136.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=herrie.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=herrie.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=herrie.org header.i=@herrie.org header.b="VfZbndLn" Received: from submission5.mail.transip.nl (unknown [10.103.8.156]) by outbound3.mail.transip.nl (Postfix) with ESMTP id 4ghVdw5ZntznFBj; Fri, 19 Jun 2026 10:10:44 +0200 (CEST) Received: from transip.email (unknown [10.100.8.81]) by submission5.mail.transip.nl (Postfix) with ESMTPA id 4ghVdw1ryxz2pRDjr; Fri, 19 Jun 2026 10:10:44 +0200 (CEST) Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Fri, 19 Jun 2026 10:10:44 +0200 From: me@herrie.org To: Konrad Dybcio Cc: Herman van Hazendonk , Georgi Djakov , Bjorn Andersson , Konrad Dybcio , Rob Herring , Krzysztof Kozlowski , Conor Dooley , linux-arm-msm@vger.kernel.org, linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 2/2] interconnect: qcom: add MSM8x60 NoC driver Reply-To: github.com@herrie.org Mail-Reply-To: github.com@herrie.org In-Reply-To: References: <20260606-submit-interconnect-msm8660-v3-0-f9da0158cdf8@herrie.org> <20260606-submit-interconnect-msm8660-v3-2-f9da0158cdf8@herrie.org> User-Agent: Webmail Message-ID: <3b8fe2ee8abb8a58939d5ded029bd08c@herrie.org> X-Sender: me@herrie.org Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: ClueGetter at submission5.mail.transip.nl DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=transip-a; d=herrie.org; t=1781856644; h=from:reply-to:subject:to: cc:references:in-reply-to:date:mime-version:content-type; bh=oaGtO+PMEUVOUfZirfkTBA88JHbSfN8UYKkF58Svw5g=; b=VfZbndLnRf6Q7kt8O9+SPfJYmof/AW7GdY3AbGavOjPyjdj6+3QAJJ+x9k8H5AhvU65EL4 VL5HSQqJP40bRkAVqOZlEPh0NRBR8Tu/VHisHTkD+0/+UflEKHXbrRdTX1AwKsJhg2Lz6S RP50cSpZylRZ6K6V7XNE386LGnsJ2htfBDbki//uOOmrnhGGuOITPZs5EHFPRy8WPbaqZV 3QZ4tvCF4THHrvjQp825U+EOyumMb1t3tusMxdP9aQbfjSsTExTurVyIlO4E5BKdD9UUv3 2pwX4u/Tb5bZpS7G9ctSdj5KT02X3T9+lfSZ1d0n82TZWcLTSDtK3MYlvERG6g== X-Report-Abuse-To: abuse@transip.nl On 2026-06-17 12:36, Konrad Dybcio wrote: > On 6/6/26 2:34 PM, Herman van Hazendonk wrote: >> Add a Qualcomm interconnect driver for the MSM8x60 family modelling >> the >> four NoC fabrics (APPSS, System, MMSS, Daytona) that connect masters >> and slaves on these Scorpion-class SoCs. The driver implements the >> interconnect-provider API to manage bandwidth between specific masters >> and slaves via the RPM arbitration tables. > > [...] > > >> +/* >> + * Minimum fabric clock rate to prevent bus starvation. >> + * >> + * When no consumers request bandwidth, the rate calculation yields >> 0, >> + * causing fabric clocks to drop to minimum. This creates bimodal >> + * performance: fast when other subsystems (like display) happen to >> + * request bandwidth, slow otherwise. >> + * >> + * 384 MHz keeps fabric fast during concurrent MDP display scanout >> + * and USB gadget traffic. legacy vendor kernel docs: "AXI bus >> frequency needs to be >> + * kept at maximum value while USB data transfers are happening." >> + * 266 MHz was insufficient - USB crashed during display activity. >> + */ >> +#define MSM8660_FABRIC_MIN_RATE 384000000UL /* 384 MHz */ > > Can you ensure that through a vote in the USB driver? > > Konrad Hi Konrad, I'm reworking the interconnect driver based on earlier feedback, but running into some regressions I need to tackle first. The driver I had was stable, the reworked one has some issues that I'm trying to tackle before submitting another version. The minimum rate will probably disappear as a result of that anyway. Thanks, Herman