From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 3656C2110F; Sat, 6 Apr 2024 07:18:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712387894; cv=none; b=PmaWRBAm5Rzcq1LIphWjxnpv4O6awHoHJAt1fItSqZ/xzkXytAB52FxJY3RHuCu7WLTKGk5tR4TW/fu6/qV5drvhJp24VE867kQjar9JNL4pCwlmyUHKUi1adqQGhtptJOXhgOA4KLHvT57Quw/Qc03NPxtdfwmcZ0ly08BNpPo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712387894; c=relaxed/simple; bh=dS8bADZziQoLtHlnkHj0dQ2paJIGjWmIuNewalgbWUA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=SxKlxYxHIrwIVL+Nwp4mC8soeo9AtoOcL/bi0MfnIJI5EVzSsQd9u8daatZw+xdzdYDiP7Ny7VnHDZoPsQN/Y9knOBLDGAfSBnp8N7Pp+TCPvJrSfGmQuZVLycZgsGKBV6/IB2EfCzF/qEAzGfyQyOH1dPK+lZfeP5V6QLgR2L8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ea6S6N6K; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ea6S6N6K" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9DA8C433C7; Sat, 6 Apr 2024 07:18:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1712387893; bh=dS8bADZziQoLtHlnkHj0dQ2paJIGjWmIuNewalgbWUA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ea6S6N6KseF8FYU91uMYJN7GD6yzmV7gab0MK5qCOM9EoxQmArIK+Qf4SmrVk7wWd w4XXWVDPPOYHHZv3evO6BMbfX4VxnqR46iifX3EPm2YW1Dotyn0Z+UrRWpPLayVoIj WKMckBsbZZVR2Azg9mLn9kc6wee9HAP7/p7lvdSggO5kzf8s8yplkVQXxU6qyMQclo hSdF9W6liKlu+0CsLtUDcVuJqsrZxKyA6LHu7IsCpPTRaYEe8NzCHJhG7GB+S3w8Ye ptA0UggHfPqrixdz4A5ghcTFtERIWFgc6L2T1QHsXRcikxX+L11f46KBcCk7g+So27 mCktSUaE1/xGQ== Date: Sat, 6 Apr 2024 12:48:09 +0530 From: Vinod Koul To: Marcel Ziswiler Cc: linux-phy@lists.infradead.org, linux-imx@nxp.com, linux-kernel@vger.kernel.org, kernel@pengutronix.de, Richard Zhu , Lucas Stach , linux-arm-kernel@lists.infradead.org, stable@vger.kernel.org, Marcel Ziswiler , Fabio Estevam , Heiko Stuebner , Kishon Vijay Abraham I , Rob Herring , Sascha Hauer , Sergio Paracuellos , Shawn Guo , Tim Harvey , Yang Li , imx@lists.linux.dev Subject: Re: [PATCH v2] phy: freescale: imx8m-pcie: fix pcie link-up instability Message-ID: References: <20240327071946.8869-1-marcel@ziswiler.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240327071946.8869-1-marcel@ziswiler.com> On 27-03-24, 08:19, Marcel Ziswiler wrote: > From: Marcel Ziswiler > > On the i.MX 8M Mini, the AUX_PLL_REFCLK_SEL has to be left at its reset > default of AUX_IN (PLL clock). > > Background Information: > In our automated testing setup, we use Delock Mini-PCIe SATA cards [1]. > While this setup has proven very stable overall we noticed upstream on > the i.MX 8M Mini fails quite regularly (about 50/50) to bring up the > PCIe link while with NXP's downstream BSP 5.15.71_2.2.2 it always works. > As that old downstream stuff was quite different, I first also tried > NXP's latest downstream BSP 6.1.55_2.2.0 which from a PCIe point of view > is fairly vanilla, however, also there the PCIe link-up was not stable. > Comparing and debugging I noticed that upstream explicitly configures > the AUX_PLL_REFCLK_SEL to I_PLL_REFCLK_FROM_SYSPLL while working > downstream [2] leaving it at reset defaults of AUX_IN (PLL clock). > Unfortunately, the TRM does not mention any further details about this > register (both for the i.MX 8M Mini as well as the Plus). > NXP confirmed their validation codes for the i.MX8MM PCIe doesn't > configure cmn_reg063 (offset: 0x18C). > BTW: On the i.MX 8M Plus we have not seen any issues with PCIe with the > exact same setup which is why I left it unchanged. This does not apply on phy/fixes, pls rebase -- ~Vinod