From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754861AbbEORsM (ORCPT ); Fri, 15 May 2015 13:48:12 -0400 Received: from bhuna.collabora.co.uk ([93.93.135.160]:48609 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754417AbbEORsK (ORCPT ); Fri, 15 May 2015 13:48:10 -0400 Message-ID: <55563152.3000407@collabora.co.uk> Date: Fri, 15 May 2015 19:48:02 +0200 From: Javier Martinez Canillas User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.2.0 MIME-Version: 1.0 To: Bartlomiej Zolnierkiewicz , Kevin Hilman CC: Thomas Abraham , Sylwester Nawrocki , Mike Turquette , Kukjin Kim , Kukjin Kim , Viresh Kumar , Lukasz Majewski , Heiko Stuebner , linux-pm@vger.kernel.org, Tomasz Figa , linux-kernel@vger.kernel.org, Chanwoo Choi , linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 0/4] cpufreq: use generic cpufreq drivers for Exynos5250 platform References: <1428946441-17058-1-git-send-email-b.zolnierkie@samsung.com> <5439319.JYC6t7bzy4@amdc1032> <7hsibtavuz.fsf@deeprootsystems.com> <4008289.pQOxzKW0Ir@amdc1032> In-Reply-To: <4008289.pQOxzKW0Ir@amdc1032> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Bartlomiej, On 04/22/2015 07:37 PM, Bartlomiej Zolnierkiewicz wrote: > > On Tuesday, April 21, 2015 04:45:56 PM Kevin Hilman wrote: >> Bartlomiej Zolnierkiewicz writes: >> >> > On Monday, April 20, 2015 02:07:33 PM Kevin Hilman wrote: >> >> Bartlomiej Zolnierkiewicz writes: >> >> >> >> > Hi, >> >> > >> >> > This patch series removes the use of Exynos5250 specific support >> >> > from exynos-cpufreq driver and enables the use of cpufreq-dt driver >> >> > for this platform. The exynos-cpufreq driver itself is also removed >> >> > as it is no longer used/needed after Exynos5250 support removal. >> >> > >> >> > This patch series has been tested on Exynos5250 based Arndale board. >> >> > >> >> > Depends on: >> >> > - next-20150330 branch of linux-next kernel tree >> >> > - "[PATCH 0/6] cpufreq: use generic cpufreq drivers for Exynos4210 >> >> > platform" [1] >> >> > - "[PATCH 0/6] cpufreq: use generic cpufreq drivers for Exynos4x12 >> >> > platform" [2] >> >> > - "[PATCH] cpufreq: exynos: remove dead ->need_apll_change method" [3] >> >> >> >> Any chance you could prepare a branch with all the dependencies for easy >> >> testing? >> > >> > All cpufreq changes with needed dependencies are now availble in >> > >> > https://github.com/bzolnier/linux.git >> > >> > repository and the branch is >> > >> > next-20150330-generic-cpufreq-exynos5420-5800-v2 >> >> Great, thanks. >> >> >> Also, The previous version from Thomas was v12, and this one is neither >> >> versioned nor has any reference to what may have changed since that >> > >> > Please note that Thomas' patchset was split on separate parts (this is >> > part #3) and heavily modified so the previous versioning was dropped. >> > >> > The cover letter of part #1 ("[PATCH 0/6] cpufreq: use generic cpufreq >> > drivers for Exynos4210 platform") contains detailed changelog on what has >> > been changed since Thomas' original v12 patch series. Individual Thomas' >> > patches which were modified by me also contain such information. >> > >> > Part #2 ("[PATCH 0/6] cpufreq: use generic cpufreq drivers for Exynos4x12 >> > platform") was entirely new code when compared to Thomas' v12 patchset so >> > its cover letter doesn't contain such detailed changelog as part #1. >> > >> > The newly posted part #4 ("[PATCH 0/8] cpufreq: add generic cpufreq driver >> > support for Exynos5250/5800 platforms" https://lkml.org/lkml/2015/4/21/314) >> > also contains the detailed changelog. >> > >> > However for part #3 (this one, "[PATCH 0/4] cpufreq: use generic cpufreq >> > drivers for Exynos5250 platform") such summary changelog got missed for >> > some reason. Here it is: >> > - split Exynos5250 support from the original patch >> > - moved E5250_CPU_DIV[0,1]() macros to clk-exynos5250.c >> > - added CPU regulator supply property for Google Spring board >> > - removed exynos-cpufreq driver entirely as it is no longer used/needed >> >> Great, thanks for clarifying. >> >> >> version. Also, on v12, I had several comments[1] and wonder if they've >> >> been addressed. >> > >> > All issues previously reported should have been fixed. If you still see >> > some problems please let me know. >> > >> > [ I see now that exynos5420-arndale-octa.dts, exynos5420-peach-pit.dts, >> > exynos5420-smdk5420.dts and exynos5800-peach-pi.dts should also have >> > been updated to contain CPU cluster regulator supply properties or else >> > if the default vdd_arm/vdd_kfc regulator state is set to too low value >> > there may be problems with stability when switching to higher than >> > default frequencies. I have posted v2 version of patch #2/8 of part #4 >> > and pushed v2 combined branch on github. Sorry for the inconvenience. ] >> >> I've now tested your v2 branch with the bL switcher disabled, CPUidle >> enabled and CPUfreq enabled. >> >> With the default governor set to performance, it fails to boot. The last >> kernel messages on the console are: > > [ Small explanation for people not following the discussion from > the start: > > This testing is relevant to part #4 of the rework: "[PATCH 0/8] > cpufreq: add generic cpufreq driver support for Exynos5250/5800 > platforms" (https://lkml.org/lkml/2015/4/21/314"), not this one > which is part #3 and has no known issues. ] > I know that Exynos5420/5422/5800 is related to part #4 and not #3 but I wanted to answer in this thread since here is where Kevin reported the issue. I tried your next-20150330-generic-cpufreq-exynos5420-5800-v2-debug branch with exynos_defconfig plus CONFIG_BL_SWITCHER disabled and: CONFIG_ARM_BIG_LITTLE_CPUFREQ=y CONFIG_ARM_DT_BL_CPUFREQ=y By default CONFIG_CPU_FREQ_GOV_PERFORMANCE=y but with that option it fails to boot as well on my Exynos5420 Peach Pit so seems to be exactly what Kevin reported on the Exynos5800 Peach Pi Chromebook. >> [...] >> [ 3.426021] cpu cpu0: bL_cpufreq_init: CPU 0 initialized >> [ 3.431189] cpu cpu4: bL_cpufreq_init: CPU 4 initialized >> >> However, with the default governor set to userspace it boots fine until >> my userspace (ubuntu) tries to enable the ondemand governor, and then it >> hangs. >> >> For it to boot, I have to disable the ondemand governor, and set the >> default governor to userspace. Disabling CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE and the performance governor and enabling the userpace governor and setting it as default makes the kernel to boot again which is the same behaviour Kevin had. Also I can see that the CPUS have a cpufreq and the scaling driver is the arm b.L one: # cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_driver arm-big-little arm-big-little arm-big-little arm-big-little arm-big-little arm-big-little arm-big-little arm-big-little > > I've tried with ARM big.LITTLE cpuidle support enabled (I've just noticed > that it is not turned on in exynos_defconfig) and my ODROID-XU3 board > fails to boot. This happens even with cpufreq support disabled (hard > lockup happens during mmc initialization which is done just after cpufreq > initialization). > > Could you please check if disabling cpuidle support helps? I don't have CPUIdle enabled since as you said is not turned on in exynos defconfig by default so I think that is just a red herring. > >> As I reported earlier on Thomas' series, I suspect this is related to >> the fact that the higher OPPs aren't really functional without voltage >> scaling also supported. > > Part #4 contains voltage scaling support for arm_big_little[_dt] driver > so this should not be a problem any longer. > > You may try next-20150330-generic-cpufreq-exynos5420-5800-v2-debug > branch from my github (with cpufreq debugging printks enabled) to check > whether the voltage scaling is indeed done on your board. > The last boot log shown on the serial console with your debug branch is: [ 3.078885] cpu cpu0: _get_cluster_clk_and_freq_table: clk: ee516a80 & freq table: ee511540, cluster: 0 [ 3.088128] cpu cpu0: bL_cpufreq_init: CPU 0 physical_cluster 0 [ 3.094024] cpu cpu0: bL_cpufreq_init: CPU 1 physical_cluster 0 [ 3.099912] cpu cpu0: bL_cpufreq_init: CPU 2 physical_cluster 0 [ 3.105871] cpu cpu0: bL_cpufreq_init: CPU 3 physical_cluster 0 [ 3.111710] cpu cpu0: bL_cpufreq_init: CPU 0 initialized [ 3.117291] cpu cpu4: _get_cluster_clk_and_freq_table: clk: ee516d80 & freq table: ee50c180, cluster: 1 [ 3.126379] cpu cpu4: bL_cpufreq_init: CPU 4 physical_cluster 1 [ 3.132276] cpu cpu4: bL_cpufreq_init: CPU 5 physical_cluster 1 [ 3.138169] cpu cpu4: bL_cpufreq_init: CPU 6 physical_cluster 1 [ 3.144069] cpu cpu4: bL_cpufreq_init: CPU 7 physical_cluster 1 [ 3.149967] cpu cpu4: bL_cpufreq_init: CPU 4 initialized [ 3.155453] arm_big_little: bL_cpufreq_set_rate: cpu: 4, old cluster: 1, new cluster: 1, freq: 1300000 [ 3.164551] arm_big_little: bL_cpufreq_set_rate_cluster: cpu 4, cluster: 1, 600 MHz, -1 mV --> 1300 MHz, -1 mV [ 3.174646] arm_big_little: bL_cpufreq_register: Registered platform driver: dt-bl [ 3.182305] Unable to handle kernel paging request at virtual address 60000186 so it seems to be a bug in the code and not about OPPs not functional due voltage scaling not working as Kevin guessed. However, as Kevin mentioned is strange that the regulator voltages are -1 as you can see in the above boot log. Also when setting a scaling_setspeed to one of the scaling available frequencies for a given CPU, I see in the log that the frequency is scaled for all the cluster and correctly reported in scaling_cur_freq but the scaled voltage is always reported as -1 again: [ 899.002840] arm_big_little: bL_cpufreq_set_rate_cluster: cpu 0, cluster: 0, 1800 MHz, -1 mV --> 1100 MHz, -1 mV [ 946.153852] arm_big_little: bL_cpufreq_set_rate: cpu: 0, old cluster: 0, new cluster: 0, freq: 1200000 [ 946.161785] arm_big_little: bL_cpufreq_set_rate_cluster: cpu 0, cluster: 0, 1100 MHz, -1 mV --> 1200 MHz, -1 mV [ 975.328748] arm_big_little: bL_cpufreq_set_rate: cpu: 4, old cluster: 1, new cluster: 1, freq: 1200000 [ 975.336663] arm_big_little: bL_cpufreq_set_rate_cluster: cpu 4, cluster: 1, 600 MHz, -1 mV --> 1200 MHz, -1 mV >> I'm also seeing the wait_until_divider_stable errors when switching >> between the available A7 OPPs. I'd reported this one earlier as well, >> along with the script to reproduce it. > > I've tried your script and it works fine for me (I only needed to change > cpu4 to cpu0 as on ODROID-XU3 CPUs 0,5,6,7 are A7 and 1,2,3,4 are A15). > > Best regards, > -- > Bartlomiej Zolnierkiewicz > Samsung R&D Institute Poland > Samsung Electronics > Best regards, Javier