From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vasco Steinmetz Subject: Slow performance of Odroid XU4 - cpufreq-dt patch needed? Date: Wed, 13 Jan 2016 17:16:33 +0100 Message-ID: <56967861.10305@kyberraum.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: Received: from nexus.metro.kyberraum.net ([195.47.195.230]:39745 "EHLO mx1.kyberraum.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752725AbcAMQpq (ORCPT ); Wed, 13 Jan 2016 11:45:46 -0500 Received: from pd9f791c7.dip0.t-ipconnect.de ([217.247.145.199] helo=[192.168.0.21]) by mx1.kyberraum.net with esmtpsa (TLSv1.2:DHE-RSA-AES256-SHA:256) (Exim 4.85) (envelope-from ) id 1aJO67-00078s-Qy for linux-samsung-soc@vger.kernel.org; Wed, 13 Jan 2016 17:16:36 +0100 Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: linux-samsung-soc@vger.kernel.org Hello, I'm trying to get an Odroid XU4 to run a more recent (e.g. 4.4+) kernel than the last semiofficial 4.2 port from hardkernel (which doesn't boot here at all). Currently (thanks to a lot of patches from you guys) the board boots happily with a kernel build from linux-next. Nonetheless the CPU performance is rather poor, though all 8 cores are enabled (no b/l switcher). It seems to me the Cortex A15s are running in their slowest performance mode (that is: lowest clock). I don't know a way to read the core clocks, as no cpufreq driver is working. Tried that also with exynos_defconfig, but with the same effect. My question therefore is: Is Bartlomiej's cpufreq-dt patchset for exynos54xx (last update was mid-December) necessary to obtain the full performance on the 5422? Unfortunately I can't get that patchset to work with the linux-next from within the last two weeks. If there's an update I would volunteer to test it thoroughly (by compiling Gentoo on it ;) on the XU4. Another point: The XU4's SD card controller supports UHS mode (tested by booting the original ubuntu with an ancient 3.x kernel on the emmc flash and reading from a UHS SD card), the current linux mainline kernel (4.4+) apparently doesn't either detect or enable UHS mode. The maximum SD speed is around 20MB/s instead of the 90MB/s the card supports and was shown with the test above. Is there patch available (maybe some missing dt clock or flag to enable UHS)? Kind regards, Vasco