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 C2559CD98F2 for ; Mon, 22 Jun 2026 17:14:58 +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:In-Reply-To:Content-Type: MIME-Version:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:References: List-Owner; bh=qjzQ4WwEP4S9tC3oy8nVsiVMsWH0bk2/jHATvq8YN7g=; b=AjwkIBsyCh6qhJ IUJn3lGJp5qpSUr5Qj9J2t5At48tBgbC16pPkn0vWEfVWS1pZSUpBfpvWA/uW7YpLRg5bxFaJfJCV av1RD+E35xaWf7FzhoE0PVEwX7EWQ2s972fafUCqonYMM6hBM2VoNVQLX/Lbl0eFMoHd7zA3jZ3WT yGXOsyJ6QmAd65iMH31vdYt+RDaD0szZDKgAXngqCZ3JslDM5kNM8ivKWcD8A8krFGFDwdlA1dgSD gLWcKdrqsaiFKSjuz7qgUG5yVPNE/HJHahAheY/SJpjPoGMe34NLOdgMgfLgPz7lq5eQ+ezRwtfXo R/JrXZW+5odnGCUJI44w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wbiEW-00000005FQf-0Kpk; Mon, 22 Jun 2026 17:14:52 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wbiEU-00000005FQN-2PF0; Mon, 22 Jun 2026 17:14:50 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id E147B601F3; Mon, 22 Jun 2026 17:14:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6C7771F000E9; Mon, 22 Jun 2026 17:14:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782148489; bh=qjzQ4WwEP4S9tC3oy8nVsiVMsWH0bk2/jHATvq8YN7g=; h=Date:From:To:Cc:Subject:In-Reply-To; b=T3jVb1nMf3BVbMVzJIa3+l8FyxOasvux+i+g5elRWyUJ3tKyCOVRbENnhNuQwA6G0 FaCXRZLUMsP7g3wqBRZyeXRqk4SRnQygKqCA44f5/gxdv+1xK/Vck+IP3MsWtA25OA rJp/w7XbBoo+T8vxg2tIJ/F/KWFVM+RSjRSNvMv9kIk9a2jTGK7P3KIo9sqfSu+6FN ZFyN+bVCG2aKNadAlcX+gXiN1ZMIjucS486ERjyxJIA0O5BmVKvcVF018PKmYwbOHi 39raliXBg05jeLL/fiXWcGJYzFqGfnepGprhNMbAwiue7GLqLTOuQUERN18GpEWh2Z WiLWFooYByexQ== Date: Mon, 22 Jun 2026 12:14:48 -0500 From: Bjorn Helgaas To: Hans Zhang <18255117159@163.com> Cc: bhelgaas@google.com, Manivannan Sadhasivam , lpieralisi@kernel.org, kwilczynski@kernel.org, heiko@sntech.de, yue.wang@amlogic.com, pali@kernel.org, neil.armstrong@linaro.org, robh@kernel.org, jingoohan1@gmail.com, khilman@baylibre.com, jbrunet@baylibre.com, martin.blumenstingl@googlemail.com, cassel@kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-amlogic@lists.infradead.org, linux-rockchip@lists.infradead.org Subject: Re: [PATCH v7 0/2] PCI: Configure Root Port MPS during host probing Message-ID: <20260622171448.GA678675@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 On Fri, Jun 19, 2026 at 11:29:39PM +0800, Hans Zhang wrote: > On 5/6/26 22:00, Manivannan Sadhasivam wrote: > > On Fri, Nov 28, 2025 at 01:09:06AM +0800, Hans Zhang wrote: > > > Current PCIe initialization exhibits a key optimization gap: Root Ports > > > may operate with non-optimal Maximum Payload Size (MPS) settings. While > > > downstream device configuration is handled during bus enumeration, Root > > > Port MPS values inherited from firmware or hardware defaults often fail > > > to utilize the full capabilities supported by controller hardware. This > > > results in suboptimal data transfer efficiency throughout the PCIe > > > hierarchy. > > > > > > This patch series addresses this by: > > > > > > 1. Core PCI enhancement (Patch 1): > > > - Proactively configures Root Port MPS during host controller probing > > > - Sets initial MPS to hardware maximum (128 << dev->pcie_mpss) > > > - Conditional on PCIe bus tuning being enabled (PCIE_BUS_TUNE_OFF unset) > > > and not in PCIE_BUS_PEER2PEER mode (which requires default 128 bytes) > > > - Maintains backward compatibility via PCIE_BUS_TUNE_OFF check > > > - Preserves standard MPS negotiation during downstream enumeration > > > > > > 2. Driver cleanup (Patch 2): > > > - Removes redundant MPS configuration from Meson PCIe controller driver > > > - Functionality is now centralized in PCI core > > > - Simplifies driver maintenance long-term > > > > > > > For the series, > > > > Reviewed-by: Manivannan Sadhasivam > > > > Bjorn: Could you please take a look? This series has been floating for a > > while... > > Hello Bjorn, > > Any chance for this series to be applied? It's too late for v7.2; we're already more than halfway through the merge window. We can look again for v7.3 after v7.2-rc1.