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 66496C76196 for ; Thu, 6 Apr 2023 15:40:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id: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=O6IlLDxSpGLnD1UMMEI2fXHntjBfVLBwfGVy/iENtb8=; b=S8apx6p1/c/QmY ADFPFxum5sLY1JgvLk770EhJ2P3OoT2mCw60ktWD0tg3mV6hix2uiiyTfuCQfx0+S9rdfEfiHZHhJ ZwXBp2Ro/H/i/grruFlXQv6RgsC0AloJUZfQ7/sVROwVI7ZnnYKWNp4e1/YXkngR3pjvVHxBJBmtN PIQBy8etjUzlmmVDpD3IKSsC8hMY5kwa9IHp6uP8AvYBiXXWmdlIAh02RUYm020JVEaXTDDaHgdzi DofyJxXFS8Arl5wKfqc5pnAk+K4GtF4a5inz6tXHxTJ4xygOLdpT49DrsTsl8szdYxDhw4HoSZErB ClZUTEDLGyYZZT0kBs3A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pkRhq-007r87-1H; Thu, 06 Apr 2023 15:39:22 +0000 Received: from mout.kundenserver.de ([212.227.126.130]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pkRhl-007r73-03; Thu, 06 Apr 2023 15:39:20 +0000 Received: from [192.168.1.141] ([37.4.248.58]) by mrelayeu.kundenserver.de (mreue010 [212.227.15.167]) with ESMTPSA (Nemesis) id 1N9MYu-1qVVyt10GS-015JJz; Thu, 06 Apr 2023 17:39:03 +0200 Message-ID: Date: Thu, 6 Apr 2023 17:39:02 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.9.0 Subject: Re: [PATCH v1 1/3] dt-bindings: PCI: brcmstb: Add two optional props To: Jim Quinlan , 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: Florian Fainelli , Lorenzo Pieralisi , =?UTF-8?Q?Krzysztof_Wilczy=c5=84ski?= , Rob Herring , Krzysztof Kozlowski , "moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE" , "moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE" , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , open list References: <20230406124625.41325-1-jim2101024@gmail.com> <20230406124625.41325-2-jim2101024@gmail.com> Content-Language: en-US From: Stefan Wahren In-Reply-To: <20230406124625.41325-2-jim2101024@gmail.com> X-Provags-ID: V03:K1:nknTnX5dlSCEMuTzZzTH1lzDx7myKdzZXx63p/ALhR5p/l1cSBy /WVL/VeWlNJRfuyPTv3z8OZICfKrmkG8l1dad5ttQkPqrRPTpFW+HjZL8FfkOz39Bx8e6cy vDV+pMAiGfNRtiH0hMZAfvPAbLsy5UAXhIAbE0EwJl3GqM7J5hdrBtwFv80E4+82mzLLblU mnBo88FTMBiQMQJibNy7Q== UI-OutboundReport: notjunk:1;M01:P0:1JPu3Fn+QcE=;R2rM/eZ8PosqU/E3uRLSGrLJ8xn tSj49CxxVi1/9bgT6bzPsMFvXzbtk/c3JjjZ4zbTou1QamVn/o6LKCFCZT7p+FQplf4XbnOrM 03IZourgA/SwhPEUg4y5658zCqcUNE//OCMFEiQsy0nYefH4LO6HMfQljXYwpoypaYaHuqV++ T7azvAR1Ugr6zap3dH8O9zr7jnCazLDzZ14DKFrLzHQ91tiAqTwVp6T2Kc0MJ0nepSx4L7TpV b+3+LnvBEBq8fF2yYz+15ff6J7p+L/01HRxcEin1Olh4pLRUomWhxMsFnIUL8vN+JIUvnBJJ3 pJtMph81OwHIxCantSeZTSds9PE/hjMbb2+QFvW4jTmmvjRmCtvZ/XWnoWtGUtQ45id/Q4r0l fqi2NRjuTBYmF+Fl9CmmrwIBZoTqVb7xEH/cgdrJvkDgKscNeMQ8std+OUy/g24bfJx7YnLBg NkgCcBMd2cjpI4/WLXCti9hDwxXmT9oQcfo1f/cKQiVCNCiw0ar0sQhoCPRXu8K6ymLMRPD9f lJz2qR3dV47nb+yHd+LfboaeADyuChHxTVpT4jA1w+3P/VbYPky894EKQfokJ6cNvIt4gh+cC Tr7qRA53J4IVD2lZbzS6yHuO3UTeD4tFCWntiemCZrY4FPj5yAEeTOcH1Eln8iLCvok5IhXR/ BEwyrnuU2Cxs23GCCzeJ5GlpzGUBGf28MckPl2r/FQ== X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230406_083917_338731_504967FD X-CRM114-Status: GOOD ( 24.07 ) 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: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Jim, Am 06.04.23 um 14:46 schrieb Jim Quinlan: > Regarding "brcm,enable-l1ss": > > The Broadcom STB/CM PCIe HW -- which is also used by RPi SOCs -- requires > the driver probe to configure one of three clkreq# modes: > > (a) clkreq# driven by the RC > (b) clkreq# driven by the EP for ASPM L0s, L1 > (c) bidirectional clkreq#, as used for L1 Substates (L1SS). > > The HW can tell the difference between (a) and (b), but does not know > when to configure (c). Further, the HW will cause a CPU abort on boot if > guesses wrong regarding the need for (c). So we introduce the boolean > "brcm,enable-l1ss" property to indicate that (c) is desired. This > property is already present in the Raspian version of Linux, but the > driver implementaion that will follow adds more details and discerns > between (a) and (b). > > Regarding "brcm,completion-timeout-msecs" > > Our HW will cause a CPU abort if the L1SS exit time is longer than the > completion abort timeout. We've been asked to make this configurable, so > we are introducing "brcm,completion-abort-msecs". > > Signed-off-by: Jim Quinlan > --- > .../devicetree/bindings/pci/brcm,stb-pcie.yaml | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/Documentation/devicetree/bindings/pci/brcm,stb-pcie.yaml b/Documentation/devicetree/bindings/pci/brcm,stb-pcie.yaml > index 7e15aae7d69e..ef4ccc05b258 100644 > --- a/Documentation/devicetree/bindings/pci/brcm,stb-pcie.yaml > +++ b/Documentation/devicetree/bindings/pci/brcm,stb-pcie.yaml > @@ -64,6 +64,18 @@ properties: > > aspm-no-l0s: true > > + brcm,enable-l1ss: > + description: Indicates that the downstream device is L1SS > + capable and L1SS is desired, e.g. by setting > + CONFIG_PCIEASPM_POWER_SUPERSAVE=y. Note that CLKREQ# not sure about this, but maybe we should avoid references to Linux kernel config parameter in a DT binding. Since the driver already gaves warning in case the DT parameter is present, but kernel config doesn't fit, this should be enough. > + assertion to clock active must be within 400ns. > + type: boolean > + > + brcm,completion-timeout-msecs: > + description: Number of msecs before completion timeout > + abort occurs. > + $ref: /schemas/types.yaml#/definitions/uint32 According to the driver at least 0 is not allowed, maybe we should define minimum and maximum here and let dtbs_check take care of invalid values? Best regards > + > brcm,scb-sizes: > description: u64 giving the 64bit PCIe memory > viewport size of a memory controller. There may be up to _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel