From patchwork Wed Mar 2 14:57:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Pali_Roh=C3=A1r?= X-Patchwork-Id: 12766214 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 9B17CC433EF for ; Wed, 2 Mar 2022 14:59:35 +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-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=rLgjqlAhBzp1noWRS5Pd+xCx8d7qqb04DoSqcQt5Mic=; b=TEqQrtI9iu7qKo tt0lF74f6tcWWblOiMIXwhnpOi5UqMartDAlOQuEsUwPPwhy+k1nmRja3KCkXHi0wx8tUHcAy7kfl 17x6X5SiT6bn8TWhVF6RR/+TdgdEpeoPcN+HW+hbin2u2d7vLH+I3rU3sZ9lJ4CoEjpDePjfJvFf5 XAGkCw/4wFHeqWVrjCxW9qPTqkcvmn4zkkwD855mErDvVK+KyZXt4LY6amMlFu9DJkvYW33p/kRko TjZF7aqVLVfY5byGzLrzvyRTYzCfCiHvj4i/Gbn0MOMshTjSlo+Bg2CoS39CmV881RzxTupyr5wZE fVckN3EWLcsgnB2i48wg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nPQQp-0034r7-UN; Wed, 02 Mar 2022 14:58:24 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nPQQM-0034iX-K4 for linux-arm-kernel@lists.infradead.org; Wed, 02 Mar 2022 14:57:56 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 09249B82025; Wed, 2 Mar 2022 14:57:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 89B47C340F4; Wed, 2 Mar 2022 14:57:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646233071; bh=dtnf8XsUhj4Osmhrrm08Dt6iD1UNUzpBusiWKcRHhvA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ldwt/TksRz4dInWWf6YNvCYjgPxXauYYGqNLgMzHlmMOdmXz+OVjr/DRgixc+00IZ FT6bqqPZpwJF9zsVodfR4RFG6a934P48LilYEDAA95qpqZQjPySZ5OflvY1cBMSMKR hGcW0+eGeqILdsu4XHkcVlj7HdfVdOsKGl8UCUFV2zQZ93ESGqyVk3PnpSlYRKrmrh 2KKtHyV8/rFvZ7aExuQfNaIQK/0fKao4/quHVqT5xHdUBoVkMk2olowzB0d2s/9kKe wty+8vb4l8HdfMKWdGD3LAu8zN2IxJlQsnsmWHi3Dj6Rg5fSIsFUajNC/e/gMJhn5Q vcn3gn1hkmZbA== Received: by pali.im (Postfix) id 1359396D; Wed, 2 Mar 2022 15:57:49 +0100 (CET) From: =?utf-8?q?Pali_Roh=C3=A1r?= To: Lorenzo Pieralisi , Bjorn Helgaas , Rob Herring , Andrew Lunn , Thomas Petazzoni , =?utf-8?q?Krzysztof_Wilczy?= =?utf-8?q?=C5=84ski?= , =?utf-8?q?Marek_Beh=C3=BAn?= , Russell King Cc: linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 2/4] dt-bindings: Add 'slot-power-limit-milliwatt' PCIe port property Date: Wed, 2 Mar 2022 15:57:31 +0100 Message-Id: <20220302145733.12606-3-pali@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20220302145733.12606-1-pali@kernel.org> References: <20220302145733.12606-1-pali@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220302_065754_845803_A646F01A X-CRM114-Status: GOOD ( 15.48 ) 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 This property specifies slot power limit in mW unit. It is a form-factor and board specific value and must be initialized by hardware. Some PCIe controllers delegate this work to software to allow hardware flexibility and therefore this property basically specifies what should host bridge program into PCIe Slot Capabilities registers. The property needs to be specified in mW unit instead of the special format defined by Slot Capabilities (which encodes scaling factor or different unit). Host drivers should convert the value from mW to needed format. Signed-off-by: Pali Rohár Signed-off-by: Marek Behún --- This change was already accepted into dt-schema repo by Rob Herring: https://github.com/devicetree-org/dt-schema/pull/66 --- Documentation/devicetree/bindings/pci/pci.txt | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/devicetree/bindings/pci/pci.txt b/Documentation/devicetree/bindings/pci/pci.txt index 6a8f2874a24d..b0cc133ed00d 100644 --- a/Documentation/devicetree/bindings/pci/pci.txt +++ b/Documentation/devicetree/bindings/pci/pci.txt @@ -32,6 +32,12 @@ driver implementation may support the following properties: root port to downstream device and host bridge drivers can do programming which depends on CLKREQ signal existence. For example, programming root port not to advertise ASPM L1 Sub-States support if there is no CLKREQ signal. +- slot-power-limit-milliwatt: + If present, this property specifies slot power limit in milliwatts. Host + drivers can parse this property and use it for programming Root Port or host + bridge, or for composing and sending PCIe Set_Slot_Power_Limit messages + through the Root Port or host bridge when transitioning PCIe link from a + non-DL_Up Status to a DL_Up Status. PCI-PCI Bridge properties -------------------------