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path: root/drivers/clk/clk.c
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| * clk: Remove unneeded NULL checksTomeu Vizoso2015-01-281-9/+0
| | | | | | | | | | | | | | | | | | As clk_unprepare_unused_subtree and clk_disable_unused_subtree are always called with a valid struct clk. Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
| * clk: Export phase functionsMaxime Ripard2015-01-271-0/+2
| | | | | | | | | | | | | | | | | | | | | | The phase setter and getter were not exported until now, which was causing build breakages when callers were compiled as module. Export these two functions. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
| * clk: Add __clk_mux_determine_rate_closestStephen Boyd2015-01-271-9/+38
| | | | | | | | | | | | | | | | | | | | Some clock drivers want to find the closest rate on the input of a mux instead of a rate that's less than or equal to the desired rate. Add a generic mux function to support this. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Kenneth Westfield <kwestfie@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
| * clk: Fix debugfs clk removal before initedSrinivas Kandagatla2015-01-271-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some of the clks can be registered & unregistered before the clk related debugfs entries are initialized at late_initcall. In the unregister path checking for only dentry before clk_debug_init() would lead dangling pointers in the debug clk list, because the list is already populated in register path and the clk pointer freed in unregister path. The side effect of not removing it from the list is either a null pointer dereference or if lucky to boot the system, the number of clk entries in debugfs disappear. We could add more checks like if (inited && !clk->dentry) but just removing the check for dentry made more sense as debugfs_remove_recursive() seems to be safe with null pointers. This will ensure that the unregistering clk would be removed from the debug list in all the code paths. Without this patch kernel would crash with log: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = c0204000 [00000000] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 1 PID: 1 Comm: swapper/0 Tainted: G B 3.19.0-rc3-00007-g412f9ba-dirty #840 Hardware name: Qualcomm (Flattened Device Tree) task: ed948000 ti: ed944000 task.ti: ed944000 PC is at strlen+0xc/0x40 LR is at __create_file+0x64/0x1dc pc : [<c04ee604>] lr : [<c049f1c4>] psr: 60000013 sp : ed945e40 ip : ed945e50 fp : ed945e4c r10: 00000000 r9 : c1006094 r8 : 00000000 r7 : 000041ed r6 : 00000000 r5 : ed4af998 r4 : c11b5e28 r3 : 00000000 r2 : ed945e38 r1 : a0000013 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 10c5787d Table: 8020406a DAC: 00000015 Process swapper/0 (pid: 1, stack limit = 0xed944248) Stack: (0xed945e40 to 0xed946000) 5e40: ed945e7c ed945e50 c049f1c4 c04ee604 c0fc2fa4 00000000 ecb748c0 c11c2b80 5e60: c0beec04 0000011c c0fc2fa4 00000000 ed945e94 ed945e80 c049f3e0 c049f16c 5e80: 00000000 00000000 ed945eac ed945e98 c08cbc50 c049f3c0 ecb748c0 c11c2b80 5ea0: ed945ed4 ed945eb0 c0fc3080 c08cbc30 c0beec04 c107e1d8 ecdf0600 c107e1d8 5ec0: c107e1d8 ecdf0600 ed945f54 ed945ed8 c0208ed4 c0fc2fb0 c026a784 c04ee628 5ee0: ed945f0c ed945ef0 c0f5d600 c04ee604 c0f5d5ec ef7fcc7d c0b40ecc 0000011c 5f00: ed945f54 ed945f10 c026a994 c0f5d5f8 c04ecc00 00000007 ef7fcc95 00000007 5f20: c0e90744 c0dd0884 ed945f54 c106cde0 00000007 c117f8c0 0000011c c0f5d5ec 5f40: c1006094 c100609c ed945f94 ed945f58 c0f5de34 c0208e50 00000007 00000007 5f60: c0f5d5ec be9b5ae0 00000000 c117f8c0 c0af1680 00000000 00000000 00000000 5f80: 00000000 00000000 ed945fac ed945f98 c0af169c c0f5dd2c ed944000 00000000 5fa0: 00000000 ed945fb0 c020f298 c0af168c 00000000 00000000 00000000 00000000 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 ebcc6d33 bfffca73 [<c04ee604>] (strlen) from [<c049f1c4>] (__create_file+0x64/0x1dc) [<c049f1c4>] (__create_file) from [<c049f3e0>] (debugfs_create_dir+0x2c/0x34) [<c049f3e0>] (debugfs_create_dir) from [<c08cbc50>] (clk_debug_create_one+0x2c/0x16c) [<c08cbc50>] (clk_debug_create_one) from [<c0fc3080>] (clk_debug_init+0xdc/0x144) [<c0fc3080>] (clk_debug_init) from [<c0208ed4>] (do_one_initcall+0x90/0x1e0) [<c0208ed4>] (do_one_initcall) from [<c0f5de34>] (kernel_init_freeable+0x114/0x1e0) [<c0f5de34>] (kernel_init_freeable) from [<c0af169c>] (kernel_init+0x1c/0xfc) [<c0af169c>] (kernel_init) from [<c020f298>] (ret_from_fork+0x14/0x3c) Code: c0b40ecc e1a0c00d e92dd800 e24cb004 (e5d02000) ---[ end trace b940e45b5e25c1e7 ]--- Fixes: 6314b6796e3c "clk: Don't hold prepare_lock across debugfs creation" Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
| * Merge branch 'clk-has-parent' into clk-nextMichael Turquette2015-01-241-0/+30
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| | * clk: Introduce clk_has_parent()Thierry Reding2015-01-241-0/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This new function is similar to clk_set_parent(), except that it doesn't actually change the parent. It merely checks that the given parent clock can be a parent for the given clock. A situation where this is useful is to check that a particular setup is valid before switching to it. One specific use-case for this is atomic modesetting in the DRM framework where setting a mode is divided into a check phase where a given configuration is validated before applying changes to the hardware. Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
| * | clk: Skip fetching index for single parent clocksStephen Boyd2015-01-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | We don't need to fetch the parent index for clocks if they only have one parent. Doing this also avoid an unnecessary allocation for the parent cache. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
* | | clk: convert clock name allocations to kstrdup_constAndrzej Hajda2015-02-131-6/+6
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clock subsystem frequently performs duplication of strings located in read-only memory section. Replacing kstrdup by kstrdup_const allows to avoid such operations. Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Mike Turquette <mturquette@linaro.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Tejun Heo <tj@kernel.org> Cc: Greg KH <greg@kroah.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* / clk: fix possible null pointer dereferenceStanimir Varbanov2015-01-171-1/+1
|/ | | | | | | | | | The commit 646cafc6 (clk: Change clk_ops->determine_rate to return a clk_hw as the best parent) opens a possibility for null pointer dereference, fix this. Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
* clk: Really fix deadlock with mmap_semStephen Boyd2014-12-151-2/+3
| | | | | | | | | | | | | | | | | Commit 6314b6796e3c (clk: Don't hold prepare_lock across debugfs creation, 2014-09-04) forgot to update one place where we hold the prepare_lock while creating debugfs directories. This means we still have the chance of a deadlock that the commit was trying to fix. Actually fix it by moving the debugfs creation outside the prepare_lock. Cc: <stable@vger.kernel.org> # 3.18 Reported-by: Russell King <rmk+kernel@arm.linux.org.uk> Fixes: 6314b6796e3c "clk: Don't hold prepare_lock across debugfs creation" Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Michael Turquette <mturquette@linaro.org> [mturquette@linaro.org: removed lockdep_assert]
* clk: Change clk_ops->determine_rate to return a clk_hw as the best parentTomeu Vizoso2014-12-031-6/+11
| | | | | | | | This is in preparation for clock providers to not have to deal with struct clk. Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
* clk: change clk_debugfs_add_file to take a struct clk_hwTomeu Vizoso2014-12-031-3/+3
| | | | | | | | Instead of struct clk, as this should be only used by providers. Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
* clk: Don't expose __clk_get_accuracyTomeu Vizoso2014-12-031-1/+1
| | | | | | | | As it's only used internally, in drivers/clk/clk.c. Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
* clk: Don't try to use a struct clk* after it could have been freedTomeu Vizoso2014-12-031-1/+4
| | | | | | | | | | As __clk_release could call kfree on clk and then we wouldn't have a safe way of getting the module that owns the clock. Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Fixes: fcb0ee6a3d33 ("clk: Implement clk_unregister") Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
* clk: Remove unused function __clk_get_prepare_countTomeu Vizoso2014-12-031-5/+0
| | | | | | Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
* clk: delete a local variable's repeated assignmentZhen Lei2014-11-191-1/+1
| | | | | | | | It's the same to the next statement, "ret = clk->parent". I think compiler will optimize it, it's just not looking well. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Michael Turquette <mturquette@linaro.org>
* Merge tag 'sunxi-clocks-for-3.18' of ↵Mike Turquette2014-09-271-4/+91
|\ | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux into clk-next Allwinner Clocks Additions for 3.18 The most important part of this serie is the addition of the phase API to handle the MMC clocks in the Allwinner SoCs. Apart from that, the A23 gained a new mbus driver, and there's a fix for a incorrect divider table on the APB0 clock.
| * clk: Add a function to retrieve phaseMaxime Ripard2014-09-271-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current phase API doesn't look into the actual hardware to get the phase value, but will rather get it from a variable only set by the set_phase function. This will cause issue when the client driver will never call the set_phase function, where we can end up having a reported phase that will not match what the hardware has been programmed to by the bootloader or what phase is programmed out of reset. Add a new get_phase function for the drivers to implement so that we can get this value. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Hans de Goede <hdegoede@redhat.com>
| * clk: introduce clk_set_phase function & callbackMike Turquette2014-09-271-4/+81
| | | | | | | | | | | | | | | | | | | | | | | | | | A common operation for a clock signal generator is to shift the phase of that signal. This patch introduces a new function to the clk.h API to dynamically adjust the phase of a clock signal. Additionally this patch introduces support for the new function in the common clock framework via the .set_phase call back in struct clk_ops. Signed-off-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Hans de Goede <hdegoede@redhat.com>
* | Merge branch 'clk-fixes' into clk-nextMike Turquette2014-09-171-1/+6
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| * | clk: prevent erronous parsing of children during rate changeTero Kristo2014-09-031-1/+6
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some cases, clocks can switch their parent with clk_set_rate, for example clk_mux can do this in some cases. Current implementation of clk_change_rate uses un-safe list iteration on the clock children, which will cause wrong clocks to be parsed in case any of the clock children change their parents during the change rate operation. Fixed by using the safe list iterator instead. The problem was detected due to some divide by zero errors generated by clock init on dra7-evm board, see discussion under http://article.gmane.org/gmane.linux.ports.arm.kernel/349180 for details. Fixes: 71472c0c06cf ("clk: add support for clock reparent on set_rate") Signed-off-by: Tero Kristo <t-kristo@ti.com> Reported-by: Nishanth Menon <nm@ti.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* / clk: Don't hold prepare_lock across debugfs creationStephen Boyd2014-09-101-46/+27
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rob Clark reports a lockdep splat that involves the prepare_lock chained with the mmap semaphore. ====================================================== [ INFO: possible circular locking dependency detected ] 3.17.0-rc1-00050-g07a489b #802 Tainted: G W ------------------------------------------------------- Xorg.bin/5413 is trying to acquire lock: (prepare_lock){+.+.+.}, at: [<c0781280>] clk_prepare_lock+0x88/0xfc but task is already holding lock: (qcom_iommu_lock){+.+...}, at: [<c079f664>] qcom_iommu_unmap+0x1c/0x1f0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (qcom_iommu_lock){+.+...}: [<c079f860>] qcom_iommu_map+0x28/0x450 [<c079eb50>] iommu_map+0xc8/0x12c [<c056c1fc>] msm_iommu_map+0xb4/0x130 [<c05697bc>] msm_gem_get_iova_locked+0x9c/0xe8 [<c0569854>] msm_gem_get_iova+0x4c/0x64 [<c0562208>] mdp4_kms_init+0x4c4/0x6c0 [<c056881c>] msm_load+0x2ac/0x34c [<c0545724>] drm_dev_register+0xac/0x108 [<c0547510>] drm_platform_init+0x50/0xf0 [<c0578a60>] try_to_bring_up_master.part.3+0xc8/0x108 [<c0578b48>] component_master_add_with_match+0xa8/0x104 [<c0568294>] msm_pdev_probe+0x64/0x70 [<c057e704>] platform_drv_probe+0x2c/0x60 [<c057cff8>] driver_probe_device+0x108/0x234 [<c057b65c>] bus_for_each_drv+0x64/0x98 [<c057cec0>] device_attach+0x78/0x8c [<c057c590>] bus_probe_device+0x88/0xac [<c057c9b8>] deferred_probe_work_func+0x68/0x9c [<c0259db4>] process_one_work+0x1a0/0x40c [<c025a710>] worker_thread+0x44/0x4d8 [<c025ec54>] kthread+0xd8/0xec [<c020e9a8>] ret_from_fork+0x14/0x2c -> #3 (&dev->struct_mutex){+.+.+.}: [<c0541188>] drm_gem_mmap+0x38/0xd0 [<c05695b8>] msm_gem_mmap+0xc/0x5c [<c02f0b6c>] mmap_region+0x35c/0x6c8 [<c02f11ec>] do_mmap_pgoff+0x314/0x398 [<c02de1e0>] vm_mmap_pgoff+0x84/0xb4 [<c02ef83c>] SyS_mmap_pgoff+0x94/0xbc [<c020e8e0>] ret_fast_syscall+0x0/0x48 -> #2 (&mm->mmap_sem){++++++}: [<c0321138>] filldir64+0x68/0x180 [<c0333fe0>] dcache_readdir+0x188/0x22c [<c0320ed0>] iterate_dir+0x9c/0x11c [<c03213b0>] SyS_getdents64+0x78/0xe8 [<c020e8e0>] ret_fast_syscall+0x0/0x48 -> #1 (&sb->s_type->i_mutex_key#3){+.+.+.}: [<c03fc544>] __create_file+0x58/0x1dc [<c03fc70c>] debugfs_create_dir+0x1c/0x24 [<c0781c7c>] clk_debug_create_subtree+0x20/0x170 [<c0be2af8>] clk_debug_init+0xec/0x14c [<c0208c70>] do_one_initcall+0x8c/0x1c8 [<c0b9cce4>] kernel_init_freeable+0x13c/0x1dc [<c0877bc4>] kernel_init+0x8/0xe8 [<c020e9a8>] ret_from_fork+0x14/0x2c -> #0 (prepare_lock){+.+.+.}: [<c087c408>] mutex_lock_nested+0x70/0x3e8 [<c0781280>] clk_prepare_lock+0x88/0xfc [<c0782c50>] clk_prepare+0xc/0x24 [<c079f474>] __enable_clocks.isra.4+0x18/0xa4 [<c079f614>] __flush_iotlb_va+0xe0/0x114 [<c079f6f4>] qcom_iommu_unmap+0xac/0x1f0 [<c079ea3c>] iommu_unmap+0x9c/0xe8 [<c056c2fc>] msm_iommu_unmap+0x64/0x84 [<c0569da4>] msm_gem_free_object+0x11c/0x338 [<c05413ec>] drm_gem_object_handle_unreference_unlocked+0xfc/0x130 [<c0541604>] drm_gem_object_release_handle+0x50/0x68 [<c0447a98>] idr_for_each+0xa8/0xdc [<c0541c10>] drm_gem_release+0x1c/0x28 [<c0540b3c>] drm_release+0x370/0x428 [<c031105c>] __fput+0x98/0x1e8 [<c025d73c>] task_work_run+0xb0/0xfc [<c02477ec>] do_exit+0x2ec/0x948 [<c0247ec0>] do_group_exit+0x4c/0xb8 [<c025180c>] get_signal+0x28c/0x6ac [<c0211204>] do_signal+0xc4/0x3e4 [<c02116cc>] do_work_pending+0xb4/0xc4 [<c020e938>] work_pending+0xc/0x20 other info that might help us debug this: Chain exists of: prepare_lock --> &dev->struct_mutex --> qcom_iommu_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(qcom_iommu_lock); lock(&dev->struct_mutex); lock(qcom_iommu_lock); lock(prepare_lock); *** DEADLOCK *** 3 locks held by Xorg.bin/5413: #0: (drm_global_mutex){+.+.+.}, at: [<c0540800>] drm_release+0x34/0x428 #1: (&dev->struct_mutex){+.+.+.}, at: [<c05413bc>] drm_gem_object_handle_unreference_unlocked+0xcc/0x130 #2: (qcom_iommu_lock){+.+...}, at: [<c079f664>] qcom_iommu_unmap+0x1c/0x1f0 stack backtrace: CPU: 1 PID: 5413 Comm: Xorg.bin Tainted: G W 3.17.0-rc1-00050-g07a489b #802 [<c0216290>] (unwind_backtrace) from [<c0211d8c>] (show_stack+0x10/0x14) [<c0211d8c>] (show_stack) from [<c087a078>] (dump_stack+0x98/0xb8) [<c087a078>] (dump_stack) from [<c027f024>] (print_circular_bug+0x218/0x340) [<c027f024>] (print_circular_bug) from [<c0283e08>] (__lock_acquire+0x1d24/0x20b8) [<c0283e08>] (__lock_acquire) from [<c0284774>] (lock_acquire+0x9c/0xbc) [<c0284774>] (lock_acquire) from [<c087c408>] (mutex_lock_nested+0x70/0x3e8) [<c087c408>] (mutex_lock_nested) from [<c0781280>] (clk_prepare_lock+0x88/0xfc) [<c0781280>] (clk_prepare_lock) from [<c0782c50>] (clk_prepare+0xc/0x24) [<c0782c50>] (clk_prepare) from [<c079f474>] (__enable_clocks.isra.4+0x18/0xa4) [<c079f474>] (__enable_clocks.isra.4) from [<c079f614>] (__flush_iotlb_va+0xe0/0x114) [<c079f614>] (__flush_iotlb_va) from [<c079f6f4>] (qcom_iommu_unmap+0xac/0x1f0) [<c079f6f4>] (qcom_iommu_unmap) from [<c079ea3c>] (iommu_unmap+0x9c/0xe8) [<c079ea3c>] (iommu_unmap) from [<c056c2fc>] (msm_iommu_unmap+0x64/0x84) [<c056c2fc>] (msm_iommu_unmap) from [<c0569da4>] (msm_gem_free_object+0x11c/0x338) [<c0569da4>] (msm_gem_free_object) from [<c05413ec>] (drm_gem_object_handle_unreference_unlocked+0xfc/0x130) [<c05413ec>] (drm_gem_object_handle_unreference_unlocked) from [<c0541604>] (drm_gem_object_release_handle+0x50/0x68) [<c0541604>] (drm_gem_object_release_handle) from [<c0447a98>] (idr_for_each+0xa8/0xdc) [<c0447a98>] (idr_for_each) from [<c0541c10>] (drm_gem_release+0x1c/0x28) [<c0541c10>] (drm_gem_release) from [<c0540b3c>] (drm_release+0x370/0x428) [<c0540b3c>] (drm_release) from [<c031105c>] (__fput+0x98/0x1e8) [<c031105c>] (__fput) from [<c025d73c>] (task_work_run+0xb0/0xfc) [<c025d73c>] (task_work_run) from [<c02477ec>] (do_exit+0x2ec/0x948) [<c02477ec>] (do_exit) from [<c0247ec0>] (do_group_exit+0x4c/0xb8) [<c0247ec0>] (do_group_exit) from [<c025180c>] (get_signal+0x28c/0x6ac) [<c025180c>] (get_signal) from [<c0211204>] (do_signal+0xc4/0x3e4) [<c0211204>] (do_signal) from [<c02116cc>] (do_work_pending+0xb4/0xc4) [<c02116cc>] (do_work_pending) from [<c020e938>] (work_pending+0xc/0x20) We can break this chain if we don't hold the prepare_lock while creating debugfs directories. We only hold the prepare_lock right now because we're traversing the clock tree recursively and we don't want the hierarchy to change during the traversal. Replacing this traversal with a simple linked list walk allows us to only grab a list lock instead of the prepare_lock, thus breaking the lock chain. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Propagate any error return from debug_init()Chris Brand2014-07-291-2/+4
| | | | | | | | | | | | | If the .debug_init op is provided, it will be called by clk_debug_create_one(). If debug_init() returns an error code, clk_debug_create_one() will return -ENOMEM, regardless of the value returned from debug_init(). Tweak the code to return the actual value returned by debug_init() instead. Signed-off-by: Chris Brand <chris.brand@linaro.org> Reviewed-by: Matt Porter <mporter@linaro.org> Reviewed-by: Alex Elder <elder@linaro.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Support for clock parents and rates assigned from device treeSylwester Nawrocki2014-07-251-2/+10
| | | | | | | | | | | | | This patch adds helper functions to configure clock parents and rates as specified through 'assigned-clock-parents', 'assigned-clock-rates' DT properties for a clock provider or clock consumer device. The helpers are now being called by the bus code for the platform, I2C and SPI busses, before the driver probing and also in the clock core after registration of a clock provider. Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: define and export clk_debugs_add_filePeter De Schrijver2014-07-021-0/+12
| | | | | | | | | | | | | Define and export a new function clk_debugs_add_file which adds a file to a existing clock's debugfs directory. This can be used by clock providers to add debugfs entries which are not related to a specific clock type. Examples include the ability to measure the rate of a clock. It can also be used by modules to create new debugfs entries. This is useful if you want to expose features for testing which can potentially cause system instability such as allowing to change a clock's rate from userspace. Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Fix build warningsSachin Kamat2014-07-011-11/+11
| | | | | | | | | | | | ‘all_lists’ and ‘orphan_list’ is accessed only when DEBUG_FS is defined. Thus, make their compilation conditional to fix the below warnings introduced by commit 27b8d5f723 ("clk: flatten clk tree in debugfs"): drivers/clk/clk.c:40:27: warning: ‘all_lists’ defined but not used [-Wunused-variable] drivers/clk/clk.c:46:27: warning: ‘orphan_list’ defined but not used [-Wunused-variable] Signed-off-by: Sachin Kamat <sachin.kamat@samsung.com> Cc: Peter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: flatten clk tree in debugfsPeter De Schrijver2014-06-261-79/+35
| | | | | | | | | | | This patch flattens the clk tree in CCF debugfs. Instead of representing the clocks and their hierarchy as a directory structure under /sys/kernel/debug/clk, each clock gets a single directory directly under /sys/kernel/debug/clk. The orphans directory is replaced by a file called clk_orphan_summary. Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: export __clk_round_rate for providersArnd Bergmann2014-06-031-0/+1
| | | | | | | | | | | | | Commit 99cbd064b0 ("clk: qcom: Support display RCG clocks") adds a use of the __clk_round_rate in a clock provided that can be built as a loadable module. This exports the symbol to avoid the build error from compiling the qcom clock as a module. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Neaten clk_summary outputGeert Uytterhoeven2014-05-231-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Limit ruler to 80 characters (was: 81), - Widen rate column by 1 for nicer spacing, - Right-align numbers and their column headers, - Move a newline to reduce the number of seq_printf() calls, - Use set_puts() for fixed strings. Before: clock enable_cnt prepare_cnt rate accuracy --------------------------------------------------------------------------------- extal 2 2 20000000 0 thermal 1 1 20000000 0 cp 0 0 10000000 0 tpu0 0 0 10000000 0 tmu0 0 0 10000000 0 main 1 1 20000000 0 pll3 0 0 1600000000 0 ddr 0 0 200000000 0 zb3d2 0 0 200000000 0 zb3 0 0 400000000 0 pll1 4 4 1560000000 0 oscclk 0 0 126953 0 rclk 1 1 31738 0 cmt1 0 0 31738 0 cmt0 1 1 31738 0 imp 0 0 390000000 0 After: clock enable_cnt prepare_cnt rate accuracy -------------------------------------------------------------------------------- extal 2 2 20000000 0 thermal 1 1 20000000 0 cp 0 0 10000000 0 tpu0 0 0 10000000 0 tmu0 0 0 10000000 0 main 1 1 20000000 0 pll3 0 0 1600000000 0 ddr 0 0 200000000 0 zb3d2 0 0 200000000 0 zb3 0 0 400000000 0 pll1 4 4 1560000000 0 oscclk 0 0 126953 0 rclk 1 1 31738 0 cmt1 0 0 31738 0 cmt0 1 1 31738 0 imp 0 0 390000000 0 Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Ignore error and NULL pointers passed to clk_{unprepare, disable}()Stephen Boyd2014-04-301-3/+6
| | | | | | | | | This simplifies error paths in drivers that use optional clocks by allowing the NULL or error pointer to be passed unconditionally. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Consolidate recalc rate logicStephen Boyd2014-04-301-16/+11
| | | | | | | | | The same if-else statement exists four times to recalculate the rate of a clock. Consolidate this logic into a single function to save some lines. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Don't check for missing ops in clk_set_parent()Stephen Boyd2014-04-301-3/+0
| | | | | | | | We dereference clk->ops during clock registration so this check for NULL ops can't possibly ever be true. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Fix slab corruption in clk_unregister()Stephen Boyd2014-04-301-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a clock is unregsitered, we iterate over the list of children and reparent them to NULL (i.e. orphan list). While iterating the list, we should use the safe iterators because the children list for this clock is changing when we reparent the children to NULL. Failure to iterate safely can lead to slab corruption like this: ============================================================================= BUG kmalloc-128 (Not tainted): Poison overwritten ----------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: 0xed0c4900-0xed0c4903. First byte 0x0 instead of 0x6b INFO: Allocated in clk_register+0x20/0x1bc age=297 cpu=2 pid=70 __slab_alloc.isra.39.constprop.42+0x410/0x454 kmem_cache_alloc_trace+0x200/0x24c clk_register+0x20/0x1bc devm_clk_register+0x34/0x68 0xbf0000f0 platform_drv_probe+0x18/0x48 driver_probe_device+0x94/0x360 __driver_attach+0x94/0x98 bus_for_each_dev+0x54/0x88 bus_add_driver+0xe8/0x204 driver_register+0x78/0xf4 do_one_initcall+0xc4/0x17c load_module+0x19ac/0x2294 SyS_init_module+0xa4/0x110 ret_fast_syscall+0x0/0x48 INFO: Freed in clk_unregister+0xd4/0x140 age=23 cpu=2 pid=73 __slab_free+0x38/0x41c clk_unregister+0xd4/0x140 release_nodes+0x164/0x1d8 __device_release_driver+0x60/0xb0 driver_detach+0xb4/0xb8 bus_remove_driver+0x5c/0xc4 SyS_delete_module+0x148/0x1d8 ret_fast_syscall+0x0/0x48 INFO: Slab 0xeec50b90 objects=25 used=0 fp=0xed0c5400 flags=0x4080 INFO: Object 0xed0c48c0 @offset=2240 fp=0xed0c4a00 Bytes b4 ed0c48b0: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Object ed0c48c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ed0c48d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ed0c48e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ed0c48f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ed0c4900: 00 00 00 00 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b ....kkkkkkkkkkkk Object ed0c4910: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ed0c4920: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ed0c4930: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkkkkkkkkkk. Redzone ed0c4940: bb bb bb bb .... Padding ed0c49e8: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Padding ed0c49f8: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ CPU: 3 PID: 75 Comm: mdev Tainted: G B 3.14.0-11033-g2054ba5ca781 #35 [<c0014be0>] (unwind_backtrace) from [<c0012240>] (show_stack+0x10/0x14) [<c0012240>] (show_stack) from [<c04b74a0>] (dump_stack+0x70/0xbc) [<c04b74a0>] (dump_stack) from [<c00f7a78>] (check_bytes_and_report+0xbc/0x100) [<c00f7a78>] (check_bytes_and_report) from [<c00f7c48>] (check_object+0x18c/0x218) [<c00f7c48>] (check_object) from [<c00f7efc>] (__free_slab+0x104/0x144) [<c00f7efc>] (__free_slab) from [<c04b6668>] (__slab_free+0x3dc/0x41c) [<c04b6668>] (__slab_free) from [<c014c008>] (load_elf_binary+0x88/0x12b4) [<c014c008>] (load_elf_binary) from [<c0105a44>] (search_binary_handler+0x78/0x18c) [<c0105a44>] (search_binary_handler) from [<c0106fc0>] (do_execve+0x490/0x5dc) [<c0106fc0>] (do_execve) from [<c0036b8c>] (____call_usermodehelper+0x134/0x168) [<c0036b8c>] (____call_usermodehelper) from [<c000f048>] (ret_from_fork+0x14/0x2c) FIX kmalloc-128: Restoring 0xed0c4900-0xed0c4903=0x6b Fixes: fcb0ee6a3d33 (clk: Implement clk_unregister) Cc: Jiada Wang <jiada_wang@mentor.com> Cc: Sylwester Nawrocki <s.nawrocki@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org> Cc: stable@vger.kernel.org
* clk: Fix double free due to devm_clk_register()Stephen Boyd2014-04-301-41/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that clk_unregister() frees the struct clk we're unregistering we'll free memory twice: first we'll call kfree() in __clk_release() with an address kmalloc doesn't know about and second we'll call kfree() in the devres layer. Remove the allocation of struct clk in devm_clk_register() and let clk_release() handle it. This fixes slab errors like: ============================================================================= BUG kmalloc-128 (Not tainted): Invalid object pointer 0xed08e8d0 ----------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Slab 0xeec503f8 objects=25 used=15 fp=0xed08ea00 flags=0x4081 CPU: 2 PID: 73 Comm: rmmod Tainted: G B 3.14.0-11032-g526e9c764381 #34 [<c0014be0>] (unwind_backtrace) from [<c0012240>] (show_stack+0x10/0x14) [<c0012240>] (show_stack) from [<c04b74dc>] (dump_stack+0x70/0xbc) [<c04b74dc>] (dump_stack) from [<c00f6778>] (slab_err+0x74/0x84) [<c00f6778>] (slab_err) from [<c04b6278>] (free_debug_processing+0x2cc/0x31c) [<c04b6278>] (free_debug_processing) from [<c04b6300>] (__slab_free+0x38/0x41c) [<c04b6300>] (__slab_free) from [<c03931bc>] (clk_unregister+0xd4/0x140) [<c03931bc>] (clk_unregister) from [<c02fb774>] (release_nodes+0x164/0x1d8) [<c02fb774>] (release_nodes) from [<c02f8698>] (__device_release_driver+0x60/0xb0) [<c02f8698>] (__device_release_driver) from [<c02f9080>] (driver_detach+0xb4/0xb8) [<c02f9080>] (driver_detach) from [<c02f8480>] (bus_remove_driver+0x5c/0xc4) [<c02f8480>] (bus_remove_driver) from [<c008c9b8>] (SyS_delete_module+0x148/0x1d8) [<c008c9b8>] (SyS_delete_module) from [<c000ef80>] (ret_fast_syscall+0x0/0x48) FIX kmalloc-128: Object at 0xed08e8d0 not freed Fixes: fcb0ee6a3d33 (clk: Implement clk_unregister) Cc: Jiada Wang <jiada_wang@mentor.com> Cc: Sylwester Nawrocki <s.nawrocki@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org> Cc: stable@vger.kernel.org
* clk: Fix minor errors in of_clk_init() function commentsSylwester Nawrocki2014-03-271-2/+2
| | | | | Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: reverse default clk provider initialization order in of_clk_init()Sylwester Nawrocki2014-03-271-1/+1
| | | | | | | | | | | | | | | This restores the default clocks registration order as parsed from devicetree, i.e. as before commit 1771b10d605d26ccee771a7fb4b08718 "clk: respect the clock dependencies in of_clk_init", for when there is no explicit parent clock dependencies between clock providers specified in the device tree. It prevents regressions (boot failure, division by 0 errors) on imx and exynos platforms. Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Tested-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: support hardware-specific debugfs entriesAlex Elder2014-03-241-0/+4
| | | | | | | | | Add a new clk_ops->debug_init method to allow a clock hardware driver to populate the clock's debugfs directory with entries beyond those common for every clock. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: turn rate change failed warning into pr_debugSascha Hauer2014-03-201-1/+1
| | | | | | | | | | If a rate change failed it's the opportunity of the caller to handle this. Do not spam the log with a message. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: respect the clock dependencies in of_clk_initGregory CLEMENT2014-03-191-4/+79
| | | | | | | | | | | | | | | | | | | | | Until now the clock providers were initialized in the order found in the device tree. This led to have the dependencies between the clocks not respected: children clocks could be initialized before their parent clocks. Instead of forcing each platform to manage its own initialization order, this patch adds this work inside the framework itself. Using the data of the device tree the of_clk_init function now delayed the initialization of a clock provider if its parent provider was not ready yet. The strict dependency check (all parents of a given clk must be initialized) was added by Boris BREZILLON Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* Merge branch 'clk-fixes' into clk-nextMike Turquette2014-02-241-6/+7
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| * clk: Correct handling of NULL clk in __clk_{get, put}Sylwester Nawrocki2014-02-241-6/+7
| | | | | | | | | | | | | | | | Ensure clk->kref is dereferenced only when clk is not NULL. Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Tested-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* | clk: return probe defer when DT clock not yet readyJean-Francois Moine2014-02-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | At probe time, a clock device may not be ready when some other device wants to use it. This patch lets the functions clk_get/devm_clk_get return a probe defer when the clock is defined in the DT but not yet available. Signed-off-by: Jean-Francois Moine <moinejf@free.fr> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* | clk: add pr_debug & kerneldoc around clk notifiersMike Turquette2014-02-241-1/+4
| | | | | | | | | | | | | | | | | | Both the pr_err and the additional kerneldoc aim to help when debugging errors thrown from within a clock rate-change notifier callback. Reported-by: Sören Brinkmann <soren.brinkmann@xilinx.com> Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* | clk: add clock-indices supportBen Dooks2014-02-231-1/+19
| | | | | | | | | | | | | | | | | | Add a property called clock-indices to allow clock-output-names to be used where the index used to lookup a clock is not a 1:1 mapping to the array position in the clock-output-names Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* | clk: Fix notifier documentationSoren Brinkmann2014-02-181-12/+3
|/ | | | | | | | | | | | | | | Contradicting to documenation, the notifier callbacks do receive the original clock rate in struct clk_notifier_data.old_rate and the new frequency struct clk_notifier_data.new_rate, independent of the notification reason. This behavior also seems to make more sense, since callbacks can use the same code to deterimine whether clocks are scaled up or down. Something which would not even possible in the post-rate-change case if the behavior was as documented. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Export more clk-provider functionsStephen Boyd2014-01-271-0/+7
| | | | | | | | | Allow drivers to be compiled as modules by exporting more clock provider functions. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* CLK: ti: add init support for clock IP blocksTero Kristo2014-01-171-3/+1
| | | | | | | | | | | | | ti_dt_clk_init_provider() can now be used to initialize the contents of a single clock IP block. This parses all the clocks under the IP block and calls the corresponding init function for them. This patch also introduces a helper function for the TI clock drivers to get register info from DT and append the master IP info to this. Signed-off-by: Tero Kristo <t-kristo@ti.com> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* clk: Add set_rate_and_parent() opStephen Boyd2014-01-161-19/+59
| | | | | | | | | | | | | | | Some of Qualcomm's clocks can change their parent and rate at the same time with a single register write. Add support for this hardware to the common clock framework by adding a new set_rate_and_parent() op. When the clock framework determines that both the parent and the rate are going to change during clk_set_rate() it will call the .set_rate_and_parent() op if available and fall back to calling .set_parent() followed by .set_rate() otherwise. Reviewed-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
* Merge branch 'clk-next-unregister' into clk-nextMike Turquette2013-12-311-11/+174
|\ | | | | | | | | Conflicts: drivers/clk/clk.c
| * clk: Implement clk_unregisterSylwester Nawrocki2013-12-041-3/+118
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | clk_unregister() is currently not implemented and it is required when a clock provider module needs to be unloaded. Normally the clock supplier module is prevented to be unloaded by taking reference on the module in clk_get(). For cases when the clock supplier module deinitializes despite the consumers of its clocks holding a reference on the module, e.g. when the driver is unbound through "unbind" sysfs attribute, there are empty clock ops added. These ops are assigned temporarily to struct clk and used until all consumers release the clock, to avoid invoking callbacks from the module which just got removed. Signed-off-by: Jiada Wang <jiada_wang@mentor.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
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