From patchwork Thu Nov 9 19:13:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jim Quinlan X-Patchwork-Id: 742940 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 8A76C32C6E for ; Thu, 9 Nov 2023 19:14:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="LB+sRhR+" Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13BE43A98 for ; Thu, 9 Nov 2023 11:14:02 -0800 (PST) Received: by mail-pj1-x102d.google.com with SMTP id 98e67ed59e1d1-2800f7c8125so1880536a91.1 for ; Thu, 09 Nov 2023 11:14:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; t=1699557241; x=1700162041; darn=vger.kernel.org; h=message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=a1ZtU5ZMqolp0WxYrzaGdVT64DAjDav43NBRtTZWZHI=; b=LB+sRhR+MQlmymmyzzMP1DpQgtsiTk8FsmCx6jSOHEXV/JseAZ+m2W1YWo8zGQNiiY FdSJWsB6QmPKyz6LQdMzTptJyJnhDjPsTAnl9eOojoUp3W0ZtExTS6XgsAX5P8qJUQzu zsPRHb4CALst5AhKH514C2h7VYSoExLliczS8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699557241; x=1700162041; h=message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=a1ZtU5ZMqolp0WxYrzaGdVT64DAjDav43NBRtTZWZHI=; b=DFtx0vkOut1RYSLRijVByQyMKFhdnamGjElNlSWlC1x4N5LnUkjV0/EfHkk/xtj0pq KVC0AbKspNuC38758E7bwTxYkQIFK1z2fndp5KLwgb0X3eo9P+jq/4Guoea3/GhTbZH6 uefDl/RSybjzeexJdJg7TRKzCvyAjRYgD+vZku27cwivQmtaO1B5qwxO3JIYqARyeI6y tb+EPpSvpkWp//Wbe75xfZoYbaOM803rIaEVy+ZTtjCchhaXdA7UtsbH9uMrKxoRFTeg YPCc4b9k5GvCT/UoIKwwQUrVGxsHdfCkYkiYXcVKnsEbFYJrHm0EV/Fv5TSWNyTFoJyC 9JDw== X-Gm-Message-State: AOJu0YyU9uVt043S+sJlBdAxxTmcFkNAHPnybDzal1pTSq73x9roEUxv EK0IlGHG/ayUwmyGY1EuW1lDfg== X-Google-Smtp-Source: AGHT+IFKQeIXiKgMCFmgv5wuFvvQpoXMS9T66pTeCj0K9JdFQuOHrsmo5pzd0sX82qkWa+oU9//dtQ== X-Received: by 2002:a17:90a:cb86:b0:280:963d:9cb with SMTP id a6-20020a17090acb8600b00280963d09cbmr181421pju.23.1699557241455; Thu, 09 Nov 2023 11:14:01 -0800 (PST) Received: from stbsrv-and-01.and.broadcom.net ([192.19.144.250]) by smtp.gmail.com with ESMTPSA id pj9-20020a17090b4f4900b00282ecb631a9sm124069pjb.25.2023.11.09.11.13.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Nov 2023 11:14:00 -0800 (PST) From: Jim Quinlan To: linux-pci@vger.kernel.org, Nicolas Saenz Julienne , Bjorn Helgaas , Lorenzo Pieralisi , Cyril Brulebois , Phil Elwell , bcm-kernel-feedback-list@broadcom.com, james.quinlan@broadcom.com Cc: Conor Dooley , devicetree@vger.kernel.org (open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS), Florian Fainelli , Jim Quinlan , Krzysztof Kozlowski , =?utf-8?q?Krzyszto?= =?utf-8?q?f_Wilczy=C5=84ski?= , linux-arm-kernel@lists.infradead.org (moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE), linux-kernel@vger.kernel.org (open list), linux-rpi-kernel@lists.infradead.org (moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE), Lorenzo Pieralisi , Rob Herring Subject: [PATCH v7 0/3] PCI: brcmstb: Configure appropriate HW CLKREQ# mode Date: Thu, 9 Nov 2023 14:13:51 -0500 Message-Id: <20231109191355.27738-1-james.quinlan@broadcom.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: v7 -- Manivannan Sadhasivam suggested (a) making the property look like a network phy-mode and (b) keeping the code simple (not counting clkreq signal appearances, un-advertising capabilites, etc). This is what I have done. The property is now "brcm,clkreq-mode" and the values may be one of "safe", "default", and "no-l1ss". The default setting is to employ the most capable power savings mode. v6 -- No code has been changed. -- Changed commit subject and comment in "#PERST" commit (Bjorn, Cyril) -- Changed sign-off and author email address for all commits. This was due to a change in Broadcom's upstreaming policy. v5 -- Remove DT property "brcm,completion-timeout-us" from "DT bindings" commit. Although this error may be reported as a completion timeout, its cause was traced to an internal bus timeout which may occur even when there is no PCIe access being processed. We set a timeout of four seconds only if we are operating in "L1SS CLKREQ#" mode. -- Correct CEM 2.0 reference provided by HW engineer, s/3.2.5.2.5/3.2.5.2.2/ (Bjorn) -- Add newline to dev_info() string (Stefan) -- Change variable rval to unsigned (Stefan) -- s/implementaion/implementation/ (Bjorn) -- s/superpowersave/powersupersave/ (Bjorn) -- Slightly modify message on "PERST#" commit. -- Rebase to torvalds master v4 -- New commit that asserts PERST# for 2711/RPi SOCs at PCIe RC driver probe() time. This is done in Raspian Linux and its absence may be the cause of a failing test case. -- New commit that removes stale comment. v3 -- Rewrote commit msgs and comments refering panics if L1SS is enabled/disabled; the code snippet that unadvertises L1SS eliminates the panic scenario. (Bjorn) -- Add reference for "400ns of CLKREQ# assertion" blurb (Bjorn) -- Put binding names in DT commit Subject (Bjorn) -- Add a verb to a commit's subject line (Bjorn) -- s/accomodat(\w+)/accommodat$1/g (Bjorn) -- Rewrote commit msgs and comments refering panics if L1SS is enabled/disabled; the code snippet that unadvertises L1SS eliminates the panic scenario. (Bjorn) v2 -- Changed binding property 'brcm,completion-timeout-msec' to 'brcm,completion-timeout-us'. (StefanW for standard suffix). -- Warn when clamping timeout value, and include clamped region in message. Also add min and max in YAML. (StefanW) -- Qualify description of "brcm,completion-timeout-us" so that it refers to PCIe transactions. (StefanW) -- Remvove mention of Linux specifics in binding description. (StefanW) -- s/clkreq#/CLKREQ#/g (Bjorn) -- Refactor completion-timeout-us code to compare max and min to value given by the property (as opposed to the computed value). v1 -- The current driver assumes the downstream devices can provide CLKREQ# for ASPM. These commits accomodate devices w/ or w/o clkreq# and also handle L1SS-capable devices. -- The Raspian Linux folks have already been using a PCIe RC property "brcm,enable-l1ss". These commits use the same property, in a backward-compatible manner, and the implementaion adds more detail and also automatically identifies devices w/o a clkreq# signal, i.e. most devices plugged into an RPi CM4 IO board. Jim Quinlan (3): dt-bindings: PCI: brcmstb: Add property "brcm,clkreq-mode" PCI: brcmstb: Configure HW CLKREQ# mode appropriate for downstream device PCI: brcmstb: Set higher value for internal bus timeout .../bindings/pci/brcm,stb-pcie.yaml | 21 +++++ drivers/pci/controller/pcie-brcmstb.c | 81 ++++++++++++++++--- 2 files changed, 92 insertions(+), 10 deletions(-) base-commit: 305230142ae0637213bf6e04f6d9f10bbcb74af8 Tested-by: Florian Fainelli