From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tobias Jakobi Subject: Re: [PATCH v4 00/20] PM / devferq: Add generic exynos bus frequency driver and new passive governor Date: Fri, 19 Feb 2016 16:05:35 +0100 Message-ID: <56C72F3F.3000603@math.uni-bielefeld.de> References: <1450075104-13705-1-git-send-email-cw00.choi@samsung.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="------------060302010802040501000202" Return-path: In-Reply-To: <1450075104-13705-1-git-send-email-cw00.choi@samsung.com> Sender: linux-samsung-soc-owner@vger.kernel.org To: Chanwoo Choi , myungjoo.ham@samsung.com, k.kozlowski@samsung.com, kgene@kernel.org Cc: kyungmin.park@samsung.com, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linux@arm.linux.org.uk, tjakobi@math.uni-bielefeld.de, linux.amoon@gmail.com, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-samsung-soc@vger.kernel.org, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org This is a multi-part message in MIME format. --------------060302010802040501000202 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Hello, I've applied the patchset to 4.5-rc4 and I'm now encountering two additional problems. The first related to debugfs entries, the second cocerning RCU locking. Here are the debugfs lines: exynos-bus bus_dmc: device_opp_debug_create_link: Failed to create link exynos-bus bus_dmc: _add_list_dev: Failed to register opp debugfs (-12) exynos-bus bus_dmc: Looking up vdd-supply from device tree exynos-bus: new bus device registered: bus_dmc (100000 KHz ~ 400000 KHz) exynos-bus bus_acp: device_opp_debug_create_link: Failed to create link exynos-bus bus_acp: _add_list_dev: Failed to register opp debugfs (-12) exynos-bus: new bus device registered: bus_acp (100000 KHz ~ 267000 KHz) exynos-bus bus_c2c: device_opp_debug_create_link: Failed to create link exynos-bus bus_c2c: _add_list_dev: Failed to register opp debugfs (-12) exynos-bus: new bus device registered: bus_c2c (100000 KHz ~ 400000 KHz) exynos-bus bus_leftbus: device_opp_debug_create_link: Failed to create link devfreq bus_dmc: Couldn't update frequency transition information. exynos-bus bus_leftbus: _add_list_dev: Failed to register opp debugfs (-12) exynos-bus bus_leftbus: Looking up vdd-supply from device tree The RCU output is a bit longer, so I attached it. With best wishes, Tobias Chanwoo Choi wrote: > This patch-set includes the two features as following. The generic exynos bus > frequency driver is able to support almost Exynos SoCs for bus frequency > scaling. And the new passive governor is able to make the dependency on > between devices for frequency/voltage scaling. I had posted the patch-set[2] > with the similiar concept. This is is revised version for exynos bus frequency. > - Generic exynos bus frequency driver > - New passive governor of DEVFREQ framework > > Depend on: > - next-20151210 tag of linux-next (master branch). > - Merge the latest devfreq patches on devfreq.git[2] (for-rafael branch). > [1] https://git.kernel.org/cgit/linux/kernel/git/mzx/devfreq.git/ (branch: for-rafael) > [2] https://lkml.org/lkml/2015/1/7/872 > : [PATCHv3 0/8] devfreq: Add generic exynos memory-bus frequency driver > > Changes from v3: > (https://lkml.org/lkml/2015/12/11/75) > - Add the reviewed-by tag from Krzysztof Kozlowski (patch2/3/13/14/15/16/17) > - Fix typo of the description on patch14 > - Modify the subject and description of patch17 > - Reorder the 'bus_xxx' device tree node alphabetically in > both exynos3250-rinato/monk.dts and exynos4412-trats/odroidu3 > > Changes from v2: > (https://lkml.org/lkml/2015/12/8/869) > - Fix typo on documentation > - Modify the more appropriate sentence on patch description > - Add the detailed description about both parent and passive bus device > - Modify the DMC frequency for Exynos4x12 DMC bus (200MHz -> 267MHz) > - Modify the voltage of 200MHz was included in Exynos3250 DMC bus (800mV -> 825mV) > - Rename OPP nodes as 'opp@' > - Delete the duplicate 'opp-microvolt' property of passive devfreq device > - Reorder the 'bus_xxx' device tree node alphabetically in exynos3250-rinato/monk.dts > - Reorder the 'bus_xxx' device tree node alphabetically in exynos4412-trats/odroidu3 > - Add new exynos4412-ppmu-common.dtsi to remove the duplicate PPMU dt node > on rinato/monk/trats2/odroid-u3 board > - Add the log message if bus device is registered to devfreq framework successfully > - Add the reviewed-by tag from Krzysztof Kozlowski > - Add the tested-by tag from Anand Moon on Odroid U3 > - Add 'SAMSUNG BUS FREQUENCY DRIVER' entry to MAINTAINERS > > Changes from v1: > (https://lkml.org/lkml/2015/11/26/260) > - Check whether the instance of regulator is NULL or not > when executing regulator_disable() because of only parent > devfreq device has the regulator instance. After fixing it, > the wake-up from suspend state is well working. (patch1) > - Fix bug which checks 'bus-clk' instead of 'bus->regulator' > after calling devm_clk_get() (on patch1) > - Update the documentation to remove the description about > DEVFREQ-EVENT subsystem (on patch2) > - Add the full name of DMC (Dynamic Memory Controller) (on patch2) > - Modify the detailed correlation of buses for Exynos3250 > on documentation (patch2) > - Add the MFC bus node for Exynos3250 (on patch11, patch12) > - Fix the duplicate frequency of bus_display on Exynos4x12.dtsi > - Add the PPMU node for exynos4412-odroidu3 > - Add the support of bus frequency for exynos4412-odroidu3 > > Detailed descirption for patch-set: > 1. Add generic exynos bus frequency driver > : This patch-set adds the generic exynos bus frequency driver for AXI bus > of sub-blocks in exynos SoC. The Samsung Exynos SoC have the common > architecture for bus between DRAM and sub-blocks in SoC. > > There are the different buses according to Exynos SoC because Exynos SoC > has the differnt sub-blocks and bus speed. In spite of this difference > among Exynos SoCs, this driver is able to support almost Exynos SoC by adding > unique data of each bus in the devicetree file. > > In devicetree, each bus node has a bus clock, regulator, operation-point > and devfreq-event devices which measure the utilization of each bus block. > > For example, > - The bus of DMC block in exynos3250.dtsi are listed below: > > bus_dmc: bus_dmc { > compatible = "samsung,exynos-bus"; > clocks = <&cmu_dmc CLK_DIV_DMC>; > clock-names = "bus"; > operating-points-v2 = <&bus_dmc_opp_table>; > status = "disabled"; > }; > > bus_dmc_opp_table: opp_table1 { > compatible = "operating-points-v2"; > opp-shared; > > opp@50000000 { > opp-hz = /bits/ 64 <50000000>; > opp-microvolt = <800000>; > }; > opp@100000000 { > opp-hz = /bits/ 64 <100000000>; > opp-microvolt = <800000>; > }; > opp@134000000 { > opp-hz = /bits/ 64 <134000000>; > opp-microvolt = <800000>; > }; > opp@200000000 { > opp-hz = /bits/ 64 <200000000>; > opp-microvolt = <825000>; > }; > opp@400000000 { > opp-hz = /bits/ 64 <400000000>; > opp-microvolt = <875000>; > }; > }; > > - Usage case to handle the frequency and voltage of bus on runtime > in exynos3250-rinato.dts are listed below: > > &bus_dmc { > devfreq-events = <&ppmu_dmc0_3>, <&ppmu_dmc1_3>; > vdd-supply = <&buck1_reg>; /* VDD_MIF */ > status = "okay"; > }; > > 2. Add new passive governor of DEVFREQ framework (patch5-patch7) > : This patch-set add the new passive governor for DEVFREQ framework. > The existing governors (ondemand, performance and so on) are used for DVFS > (Dynamic Voltage and Frequency Scaling) drivers. The existing governors > are independently used for specific device driver which don't give the > influence to other device drviers and also don't receive the effect from > other device drivers. > > The passive governor depends on operation of parent driver with existing > governors(ondemand, performance and so on) extremely and is not able to > decide the new frequency by oneself. According to the decided new frequency > of parent driver with governor, the passive governor uses it to decide > the appropriate frequency for own device driver. The passive governor > must need the following information from device tree: > > For exameple, > There are one more bus device drivers in Exynos3250 which need to > change their source clock according to their utilization on runtime. > But, they share the same power line (e.g., regulator). So, LEFTBUS bus > driver is operated as parent with ondemand governor and then the rest > device driver with passive governor. > > The buses of Internal block in exynos3250.dtsi are listed below: > When LEFTBUS bus driver (parent) changes the bus frequency with > ondemand governor on runtime, the rest bus devices which sharing > the same power line (VDD_INT) will change the each bus frequency > according to the decision of LEFTBUS bus driver (parent). > > - INT (Internal) block > : VDD_INT |--- LEFTBUS > |--- PERIL > |--- MFC > |--- G3D > |--- RIGHTBUS > |--- FSYS > |--- LCD0 > |--- PERIR > |--- ISP > |--- CAM > > - The buss of INT block in exynos3250.dtsi are listed below: > bus_leftbus: bus_leftbus { > compatible = "samsung,exynos-bus"; > clocks = <&cmu CLK_DIV_GDL>; > clock-names = "bus"; > operating-points-v2 = <&bus_leftbus_opp_table>; > status = "disabled"; > }; > > bus_rightbus: bus_rightbus { > compatible = "samsung,exynos-bus"; > clocks = <&cmu CLK_DIV_GDR>; > clock-names = "bus"; > operating-points-v2 = <&bus_leftbus_opp_table>; > status = "disabled"; > }; > > (Omit the rest bus dt node) > > - Usage case to handle the frequency and voltage of bus on runtime > in exynos3250-rinato.dts are listed below: > /* Parent bus device of VDD_INT */ > &bus_leftbus { > devfreq-events = <&ppmu_leftbus_3>, <&ppmu_rightbus_3>; > vdd-supply = <&buck3_reg>; > status = "okay"; > }; > > /* Passive bus device depend on LEFTBUS bus. */ > &bus_rightbus { > devfreq = <&bus_leftbus>; /* 'devfreq' property indicates > the phandle of parent device. */ > status = "okay"; > }; > > (Omit the rest bus dt node) > > Chanwoo Choi (20): > PM / devfreq: exynos: Add generic exynos bus frequency driver > PM / devfreq: exynos: Add documentation for generic exynos bus frequency driver > ARM: dts: Add DMC bus node for Exynos3250 > ARM: dts: Add DMC bus frequency for exynos3250-rinato/monk > PM / devfreq: Add new passive governor > PM / devfreq: Add devfreq_get_devfreq_by_phandle() > PM / devfreq: Show the related information according to governor type > PM / devfreq: exynos: Add support of bus frequency of sub-blocks using passive governor > PM / devfreq: exynos: Update documentation for bus devices using passive governor > PM / devfreq: exynos: Add the detailed correlation between sub-blocks and power line > PM / devfreq: exynos: Remove unused exynos4/5 busfreq driver > MAINTAINERS: Add samsung bus frequency driver entry > ARM: dts: Add bus nodes using VDD_INT for Exynos3250 > ARM: dts: Add bus nodes using VDD_MIF for Exynos4x12 > ARM: dts: Add bus nodes using VDD_INT for Exynos4x12 > ARM: dts: Add bus nodes using VDD_MIF for Exynos4210 > ARM: dts: Add exynos4412-ppmu-common dtsi to delete duplicate PPMU nodes > ARM: dts: Add support of bus frequency using VDD_INT for exynos3250-rinato > ARM: dts: Expand the voltage range of buck1/3 regulator for exynos4412-odroidu3 > ARM: dts: Add support of bus frequency for exynos4412-trats/odroidu3 > > .../devicetree/bindings/devfreq/exynos-bus.txt | 388 +++++++ > MAINTAINERS | 9 + > arch/arm/boot/dts/exynos3250-monk.dts | 47 +- > arch/arm/boot/dts/exynos3250-rinato.dts | 88 +- > arch/arm/boot/dts/exynos3250.dtsi | 181 ++++ > arch/arm/boot/dts/exynos4210.dtsi | 159 +++ > arch/arm/boot/dts/exynos4412-odroid-common.dtsi | 54 +- > arch/arm/boot/dts/exynos4412-ppmu-common.dtsi | 50 + > arch/arm/boot/dts/exynos4412-trats2.dts | 88 +- > arch/arm/boot/dts/exynos4x12.dtsi | 174 ++++ > drivers/devfreq/Kconfig | 37 +- > drivers/devfreq/Makefile | 2 + > drivers/devfreq/devfreq.c | 120 ++- > drivers/devfreq/exynos/Makefile | 3 +- > drivers/devfreq/exynos/exynos-bus.c | 556 +++++++++++ > drivers/devfreq/exynos/exynos4_bus.c | 1055 -------------------- > drivers/devfreq/exynos/exynos4_bus.h | 110 -- > drivers/devfreq/exynos/exynos5_bus.c | 431 -------- > drivers/devfreq/exynos/exynos_ppmu.c | 119 --- > drivers/devfreq/exynos/exynos_ppmu.h | 86 -- > drivers/devfreq/governor.h | 7 + > drivers/devfreq/governor_passive.c | 109 ++ > drivers/devfreq/governor_performance.c | 1 + > drivers/devfreq/governor_powersave.c | 1 + > drivers/devfreq/governor_simpleondemand.c | 1 + > drivers/devfreq/governor_userspace.c | 1 + > include/linux/devfreq.h | 26 + > 27 files changed, 1955 insertions(+), 1948 deletions(-) > create mode 100644 Documentation/devicetree/bindings/devfreq/exynos-bus.txt > create mode 100644 arch/arm/boot/dts/exynos4412-ppmu-common.dtsi > create mode 100644 drivers/devfreq/exynos/exynos-bus.c > delete mode 100644 drivers/devfreq/exynos/exynos4_bus.c > delete mode 100644 drivers/devfreq/exynos/exynos4_bus.h > delete mode 100644 drivers/devfreq/exynos/exynos5_bus.c > delete mode 100644 drivers/devfreq/exynos/exynos_ppmu.c > delete mode 100644 drivers/devfreq/exynos/exynos_ppmu.h > create mode 100644 drivers/devfreq/governor_passive.c > --------------060302010802040501000202 Content-Type: text/plain; charset=UTF-8; name="devfreq_rcu.txt" Content-Transfer-Encoding: quoted-printable Content-Disposition: attachment; filename="devfreq_rcu.txt" [ 3.041556] =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D [ 3.041560] [ INFO: suspicious RCU usage. ] [ 3.041569] 4.5.0-rc4-debug+ #2 Tainted: G W =20 [ 3.041572] ------------------------------- [ 3.041578] drivers/base/power/opp/core.c:377 Missing rcu_read_lock() = or dev_opp_list_lock protection! [ 3.041580]=20 other info that might help us debug this: [ 3.041586]=20 rcu_scheduler_active =3D 1, debug_locks =3D 0 [ 3.041592] 3 locks held by kworker/u8:3/861: [ 3.041635] #0: ("%s"("devfreq_wq")){.+.+..}, at: [] proce= ss_one_work+0x134/0x7ac [ 3.041648] #1: ((&(&devfreq->work)->work)){+.+...}, at: [= ] process_one_work+0x134/0x7ac [ 3.041675] #2: (&devfreq->lock){+.+.+.}, at: [] devfreq_m= onitor+0x24/0x80 [ 3.041678]=20 stack backtrace: [ 3.041686] CPU: 1 PID: 861 Comm: kworker/u8:3 Tainted: G W = 4.5.0-rc4-debug+ #2 [ 3.041688] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 3.041699] Workqueue: devfreq_wq devfreq_monitor [ 3.041706] Backtrace:=20 [ 3.041736] [] (dump_backtrace) from [] (show_stac= k+0x18/0x1c) [ 3.041749] r6:c0845660 r5:60000053 r4:00000000 r3:dc8ba700 [ 3.041773] [] (show_stack) from [] (dump_stack+0x= b0/0xdc) [ 3.041787] [] (dump_stack) from [] (lockdep_rcu_s= uspicious+0xe8/0x11c) [ 3.041800] r8:ee381ea8 r7:c0757330 r6:00000179 r5:c0757350 r4:ee098c= 80 r3:00000000 [ 3.041817] [] (lockdep_rcu_suspicious) from [] (d= ev_pm_opp_find_freq_ceil+0xe8/0x100) [ 3.041827] r7:ee932a00 r6:c0865ac0 r5:eeb43410 r4:ee381e1c [ 3.041835] [] (dev_pm_opp_find_freq_ceil) from []= (devfreq_recommended_opp+0x3c/0x54) [ 3.041845] r6:ee381e1c r5:eeb43410 r4:ee381e1c r3:03c1f399 [ 3.041852] [] (devfreq_recommended_opp) from [] (= devfreq_passive_get_target_freq+0xd8/0xfc) [ 3.041858] r5:ee35e400 r4:ee35dc00 [ 3.041864] [] (devfreq_passive_get_target_freq) from [] (update_devfreq_passive+0x48/0x94) [ 3.041875] r6:03c1f399 r5:ee35df3c r4:ee35e400 r3:c0473490 [ 3.041881] [] (update_devfreq_passive) from [] (u= pdate_devfreq+0x12c/0x168) [ 3.041889] r6:00000000 r5:ee35df3c r4:ee35dc00 [ 3.041895] [] (update_devfreq) from [] (devfreq_m= onitor+0x2c/0x80) [ 3.041904] r6:ee35dc00 r5:ee35dc08 r4:ee35deb4 [ 3.041910] [] (devfreq_monitor) from [] (process_= one_work+0x208/0x7ac) [ 3.041920] r6:ee80ac00 r5:ee35deb4 r4:ee12d600 r3:c0470c74 [ 3.041925] [] (process_one_work) from [] (worker_= thread+0x4c/0x514) [ 3.041938] r10:ee12d600 r9:ee380000 r8:c0822100 r7:ee80ac34 r6:00000= 088 r5:ee12d618 [ 3.041942] r4:ee80ac00 [ 3.041956] [] (worker_thread) from [] (kthread+0x= 108/0x120) [ 3.041969] r10:00000000 r9:00000000 r8:00000000 r7:c0046a18 r6:ee12d= 600 r5:ee1ea340 [ 3.041973] r4:00000000 [ 3.041982] [] (kthread) from [] (ret_from_fork+0x= 14/0x24) [ 3.041992] r7:00000000 r6:00000000 r5:c004d644 r4:ee1ea340 [ 3.083806] devfreq bus_leftbus: Couldn't update frequency transition = information. --------------060302010802040501000202--