Hello, This patchset performs cleanup of the clock handling during Exynos power domain power on/off sequences. This has been achieved by moving all clock related operations from Exynos power domain driver to respective Exynos clock controller drivers. Such change is possible after introducinng runtime power-management in common clock framework. Another nice result of this cleanup is removal of deplock warning reported in the following thread (the 'second issue'): https://www.spinics.net/lists/linux-samsung-soc/msg61766.html [ 5.932966] ====================================================== [ 5.937199] usb 5-1: new high-speed USB device number 2 using xhci-hcd [ 5.939073] WARNING: possible circular locking dependency detected [ 5.939110] 4.15.0-rc8-next-20180116 #1121 Tainted: G W [ 5.958143] ------------------------------------------------------ [ 5.964299] kworker/0:1/59 is trying to acquire lock: [ 5.969304] (&genpd->mlock){+.+.}, at: [<6abc3872>] genpd_runtime_resume+0x104/0x260 [ 5.977155] [ 5.977155] but task is already holding lock: [ 5.982926] (prepare_lock){+.+.}, at: [<74cef905>] clk_prepare_lock+0x10/0xf8 [ 5.990143] [ 5.990143] which lock already depends on the new lock. [ 5.990143] [ 5.998309] [ 5.998309] the existing dependency chain (in reverse order) is: [ 6.005739] [ 6.005739] -> #1 (prepare_lock){+.+.}: [ 6.011042] mutex_lock_nested+0x1c/0x24 [ 6.015419] clk_prepare_lock+0x50/0xf8 [ 6.019755] clk_unprepare+0x1c/0x2c [ 6.023841] exynos_pd_power+0x1a8/0x1e4 [ 6.028246] genpd_power_off+0x160/0x274 [ 6.032664] genpd_power_off_work_fn+0x2c/0x40 [ 6.037630] process_one_work+0x2d4/0x8f0 [ 6.042104] worker_thread+0x38/0x584 [ 6.046268] kthread+0x138/0x168 [ 6.049981] ret_from_fork+0x14/0x20 [ 6.054044] (null) [ 6.056794] [ 6.056794] -> #0 (&genpd->mlock){+.+.}: [ 6.062238] __mutex_lock+0x7c/0xa68 [ 6.066278] mutex_lock_nested+0x1c/0x24 [ 6.070703] genpd_runtime_resume+0x104/0x260 [ 6.075557] __rpm_callback+0xc0/0x21c [ 6.079792] rpm_callback+0x20/0x80 [ 6.083774] rpm_resume+0x558/0x7dc [ 6.087762] __pm_runtime_resume+0x60/0x98 [ 6.092367] clk_core_prepare+0x44/0x490 [ 6.096783] clk_prepare+0x20/0x30 [ 6.100674] amba_get_enable_pclk+0x2c/0x60 [ 6.105363] amba_device_try_add+0x8c/0x20c [ 6.110041] amba_deferred_retry_func+0x40/0xbc [ 6.115080] process_one_work+0x2d4/0x8f0 [ 6.119569] worker_thread+0x38/0x584 [ 6.123727] kthread+0x138/0x168 [ 6.127444] ret_from_fork+0x14/0x20 [ 6.131510] (null) [ 6.134263] [ 6.134263] other info that might help us debug this: [ 6.134263] [ 6.142328] Possible unsafe locking scenario: [ 6.142328] [ 6.148178] CPU0 CPU1 [ 6.152656] ---- ---- [ 6.157160] lock(prepare_lock); [ 6.160439] lock(&genpd->mlock); [ 6.166365] lock(prepare_lock); [ 6.172168] lock(&genpd->mlock); [ 6.175517] [ 6.175517] *** DEADLOCK *** [ 6.175517] [ 6.181475] 4 locks held by kworker/0:1/59: [ 6.185580] #0: ((wq_completion)"events"){+.+.}, at: [<f71c19aa>] process_one_work+0x210/0x8f0 [ 6.194407] #1: ((deferred_retry_work).work){+.+.}, at: [<f71c19aa>] process_one_work+0x210/0x8f0 [ 6.203422] #2: (deferred_devices_lock){+.+.}, at: [<3e940c1f>] amba_deferred_retry_func+0x1c/0xbc [ 6.212522] #3: (prepare_lock){+.+.}, at: [<74cef905>] clk_prepare_lock+0x10/0xf8 [ 6.220128] [ 6.220128] stack backtrace: [ 6.224438] CPU: 0 PID: 59 Comm: kworker/0:1 Tainted: G W 4.15.0-rc8-next-20180116 #1121 [ 6.233757] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 6.239791] Workqueue: events amba_deferred_retry_func [ 6.244929] [<c0111f90>] (unwind_backtrace) from [<c010e360>] (show_stack+0x10/0x14) [ 6.252670] [<c010e360>] (show_stack) from [<c0a19860>] (dump_stack+0x98/0xc4) [ 6.259877] [<c0a19860>] (dump_stack) from [<c0181478>] (print_circular_bug.constprop.17+0x210/0x32c) [ 6.269077] [<c0181478>] (print_circular_bug.constprop.17) from [<c01848f8>] (__lock_acquire+0x155c/0x1ac8) [ 6.278786] [<c01848f8>] (__lock_acquire) from [<c0185884>] (lock_acquire+0xe0/0x2bc) [ 6.286558] [<c0185884>] (lock_acquire) from [<c0a31788>] (__mutex_lock+0x7c/0xa68) [ 6.294181] [<c0a31788>] (__mutex_lock) from [<c0a32190>] (mutex_lock_nested+0x1c/0x24) [ 6.302161] [<c0a32190>] (mutex_lock_nested) from [<c05885dc>] (genpd_runtime_resume+0x104/0x260) [ 6.311008] [<c05885dc>] (genpd_runtime_resume) from [<c057c6c4>] (__rpm_callback+0xc0/0x21c) [ 6.319484] [<c057c6c4>] (__rpm_callback) from [<c057c840>] (rpm_callback+0x20/0x80) [ 6.327185] [<c057c840>] (rpm_callback) from [<c057c2a8>] (rpm_resume+0x558/0x7dc) [ 6.334721] [<c057c2a8>] (rpm_resume) from [<c057c58c>] (__pm_runtime_resume+0x60/0x98) [ 6.342706] [<c057c58c>] (__pm_runtime_resume) from [<c04b7f6c>] (clk_core_prepare+0x44/0x490) [ 6.351297] [<c04b7f6c>] (clk_core_prepare) from [<c04ba304>] (clk_prepare+0x20/0x30) [ 6.359081] [<c04ba304>] (clk_prepare) from [<c04b52f4>] (amba_get_enable_pclk+0x2c/0x60) [ 6.367229] [<c04b52f4>] (amba_get_enable_pclk) from [<c04b5510>] (amba_device_try_add+0x8c/0x20c) [ 6.376164] [<c04b5510>] (amba_device_try_add) from [<c04b56f8>] (amba_deferred_retry_func+0x40/0xbc) [ 6.385361] [<c04b56f8>] (amba_deferred_retry_func) from [<c01465b4>] (process_one_work+0x2d4/0x8f0) [ 6.394457] [<c01465b4>] (process_one_work) from [<c0147860>] (worker_thread+0x38/0x584) [ 6.402497] [<c0147860>] (worker_thread) from [<c014d794>] (kthread+0x138/0x168) [ 6.409852] [<c014d794>] (kthread) from [<c01010b4>] (ret_from_fork+0x14/0x20) This patchset affects Exynos5250 and Exynos5420/5422/5800 SoCs. Changes has been tested on Snow Chromebook (Exynos5250), Peach-Pit Chromebook2 (Exynos5420) and Odroid XU3/XU4 (Exynos5422) boards with latest linux-next kernel. If possible I would like to get patches 1-4 merged to current clk-next tree and patches 5-6 queued to next merge cycle. Best regards Marek Szyprowski Samsung R&D Institute Poland Changelog: v2: - fixed minor style issues pointed by Krzysztof Kozlowski Patch summary: Marek Szyprowski (6): soc: samsung: pm_domains: Add blacklisting clock handling clk: samsung: Add Exynos5 sub-CMU clock driver clk: samsung: exynos5420: Move PD-dependent clocks to Exynos5 sub-CMU driver clk: samsung: exynos5250: Move PD-dependent clocks to Exynos5 sub-CMU driver soc: samsung: pm_domains: Deprecate support for clocks ARM: dts: exynos: Remove obsolete clock properties from power domains .../devicetree/bindings/power/pd-samsung.txt | 20 +-- arch/arm/boot/dts/exynos5250.dtsi | 4 - arch/arm/boot/dts/exynos5420.dtsi | 14 -- drivers/clk/samsung/Makefile | 2 + drivers/clk/samsung/clk-exynos5-subcmu.c | 188 +++++++++++++++++++++ drivers/clk/samsung/clk-exynos5-subcmu.h | 26 +++ drivers/clk/samsung/clk-exynos5250.c | 51 ++++-- drivers/clk/samsung/clk-exynos5420.c | 121 ++++++++++--- drivers/soc/samsung/pm_domains.c | 79 +-------- 9 files changed, 351 insertions(+), 154 deletions(-) create mode 100644 drivers/clk/samsung/clk-exynos5-subcmu.c create mode 100644 drivers/clk/samsung/clk-exynos5-subcmu.h -- 2.15.0 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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