From patchwork Sun Oct 31 15:07:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Marek_Beh=C3=BAn?= X-Patchwork-Id: 12595173 X-Patchwork-Delegate: robh@kernel.org 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D83D8C433F5 for ; Sun, 31 Oct 2021 15:07:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ABA9760234 for ; Sun, 31 Oct 2021 15:07:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229754AbhJaPJq (ORCPT ); Sun, 31 Oct 2021 11:09:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:53454 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229685AbhJaPJm (ORCPT ); Sun, 31 Oct 2021 11:09:42 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id F19A160234; Sun, 31 Oct 2021 15:07:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1635692830; bh=ql/X/2+8Hkm6EWf0l7VhroUTIs/nYfkWm+Y9KW/UZ2w=; h=From:To:Cc:Subject:Date:From; b=YRIufha4qnlWgLSEdLDjx7PjLjb+K//idLz9AO2d3aVPFJ7139PZSj+kW512GQgQx vMvpLGojPDeKQcz/cNSYYLQOUMrtDkiOg8djM7F7jBoK8merIwFaiqA2rF2xwKBJ7/ L/2hArUysYSGA2DVheQnD6NOEa23iInPiUGTeppEN72SPRyvL8ybhM7UmWWtwTzcnN UNOzIfQmo3kd0C5gmZmj+de5Yvh2eGMJjxrh4xVqWEjTXE7DVNYYmwmEEdytMityMA wDRRdJBILCviuZg/Q7mN33AhQi4KyMaibj392h0HGrUX/wgrUozSHYlS6LxFEFwhpa yI2X/IYoitQcA== From: =?utf-8?q?Marek_Beh=C3=BAn?= To: devicetree@vger.kernel.org, robh+dt@kernel.org, linux-pci@vger.kernel.org, Bjorn Helgaas Cc: =?utf-8?q?Pali_Roh=C3=A1r?= , =?utf-8?q?Marek_Beh=C3=BA?= =?utf-8?q?n?= Subject: [PATCH dt + pci 1/2] dt-bindings: Add 'slot-power-limit-milliwatt' PCIe port property Date: Sun, 31 Oct 2021 16:07:05 +0100 Message-Id: <20211031150706.27873-1-kabel@kernel.org> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Pali Rohár 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 --- 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..7296d599c5ac 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-miliwatt: + 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 -------------------------