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 BCD8ED68BDD for ; Sun, 17 Nov 2024 08:00:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type: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=NcRmmsv3R8vl1bwH7VizZ/8aTvi9nV4YC/Ru3oQ8iMs=; b=4ob89kF4gMRGBZ 5qg/gbOwLDLcmnYEXdkpF2xGkOi/L2W2/oUXJ8fpxoIsKTbDRLMHUderTk8PnJ7w0C76JXnV444YZ wQJy9sRIkaex1VTDav7SUhTAqdOEmKnuiYC9aizwUTBdDEknlP5Nj+kl9ZTj7CzCmOKWAYIBAJbly mtnwNIe1T1pXiRUODWms7h98b0DjPy3/S5kyVpzDpi+WiQ0RimJKk0Tzcaqu09X2FCZ52GfDhWr7i dX0zNTqs3AtX3KXzsi3k+QFhj9jBPUU47SwP3uza8EFdigDWieqa7bpWMvi5EzD6ab7XcrcLXSnRX FlXpx199QEr3Ghxus4fg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tCaDC-00000006zCE-1O7O; Sun, 17 Nov 2024 08:00:50 +0000 Received: from nyc.source.kernel.org ([147.75.193.91]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tCaD8-00000006zBY-3hCq for linux-rockchip@lists.infradead.org; Sun, 17 Nov 2024 08:00:48 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 0C71BA40C2F; Sun, 17 Nov 2024 07:58:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7AB0FC4CECD; Sun, 17 Nov 2024 08:00:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731830445; bh=yG/Prvv2cW4FAbQIxSEqLgZUGZ3kv80l7NsNSnpg53M=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=Gqfs5s6yPfPvpIR/sBXHis0a0AI5ejKOd74ZA3OIxcF77rHXSmvJu6tZGO5WjO2sp VI8Ds5IkGhecdxwAIcTLz4Ii1blB06aUeab/Af7dijufr/PetogT+B1f3+IoC9doIP 3rBc/91TRUKN/Yysf1UEKuVllyeahSzksv5EiaLsZZhz+9Ly07mlMyl+OsTzRShHm5 X8V8KYQUq8Ck4WDOuIses5VrALQ7Vb1T6Gbdf8qWLXCGzJD6jL9tlTlV3bsKx4J4cG gC65Sjr5DkIrvv2vzMS8kW9StasNCjgdW+gZm0GBTokQWSjJwjZBZ87GgML4RsUhhX 7CDgY4aUilWUA== Message-ID: <8393e56d-8ba1-436d-ad97-ec44893d2f6f@kernel.org> Date: Sun, 17 Nov 2024 17:00:42 +0900 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 12/14] PCI: rockchip-ep: Improve link training To: Bjorn Helgaas Cc: Manivannan Sadhasivam , Lorenzo Pieralisi , Kishon Vijay Abraham I , Shawn Lin , =?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= , Bjorn Helgaas , linux-pci@vger.kernel.org, Rob Herring , Krzysztof Kozlowski , Conor Dooley , Heiko Stuebner , devicetree@vger.kernel.org, linux-rockchip@lists.infradead.org, Rick Wertenbroek , Niklas Cassel References: <20241115230319.GA2065576@bhelgaas> From: Damien Le Moal Content-Language: en-US Organization: Western Digital Research In-Reply-To: <20241115230319.GA2065576@bhelgaas> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241117_000047_004772_5B316351 X-CRM114-Status: GOOD ( 10.15 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org On 11/16/24 08:03, Bjorn Helgaas wrote: > On Thu, Oct 17, 2024 at 10:58:47AM +0900, Damien Le Moal wrote: >> The Rockchip RK3399 TRM V1.3 Part2, Section 17.5.8.1.2, step 7, >> describes the endpoint mode link training process clearly and states >> that: >> Insure link training completion and success by observing link_st field >> in PCIe Client BASIC_STATUS1 register change to 2'b11. If both side >> support PCIe Gen2 speed, re-train can be Initiated by asserting the >> Retrain Link field in Link Control and Status Register. The software >> should insure the BASIC_STATUS0[negotiated_speed] changes to "1", that >> indicates re-train to Gen2 successfully. > > Since this only adds code and doesn't change existing code, I assume > this hardware doesn't automatically train to gen2 without this new > software assistance? > > So the effect of this change is to use gen2 speed when supported by > both partners, when previously we only got gen1? Yes. The host side has something similar as well. -- Damien Le Moal Western Digital Research _______________________________________________ Linux-rockchip mailing list Linux-rockchip@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-rockchip