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fix dead-lock bug between reset and clk
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there is a global spinlock between reset and clk, if locked in reset,
then print some debug information, maybe dead-lock when uart driver
try to disable clk.

Backtrace stopped: frame did not save the PC
(gdb) thread 4
[Switching to thread 4 (Thread 4)]
#0  cpu_relax () at ./arch/riscv/include/asm/vdso/processor.h:22
22      ./arch/riscv/include/asm/vdso/processor.h: No such file or directory.
(gdb) bt
#0  cpu_relax () at ./arch/riscv/include/asm/vdso/processor.h:22
#1  arch_spin_lock (lock=lock@entry=0xffffffff81a57cd0 <enable_lock>) at ./include/asm-generic/spinlock.h:49
#2  do_raw_spin_lock (lock=lock@entry=0xffffffff81a57cd0 <enable_lock>) at ./include/linux/spinlock.h:186
#3  0xffffffff80aa21ce in __raw_spin_lock_irqsave (lock=0xffffffff81a57cd0 <enable_lock>) at ./include/linux/spinlock_api_smp.h:111
#4  _raw_spin_lock_irqsave (lock=lock@entry=0xffffffff81a57cd0 <enable_lock>) at kernel/locking/spinlock.c:162
#5  0xffffffff80563416 in clk_enable_lock () at ./include/linux/spinlock.h:325
torvalds#6  0xffffffff805648de in clk_core_disable_lock (core=0xffffffd900512500) at drivers/clk/clk.c:1062
torvalds#7  0xffffffff8056527e in clk_disable (clk=<optimized out>) at drivers/clk/clk.c:1084
torvalds#8  clk_disable (clk=0xffffffd9048b5100) at drivers/clk/clk.c:1079
torvalds#9  0xffffffff8059e5d4 in serial_pxa_console_write (co=<optimized out>, s=0xffffffff81a68250 <text> "[   14.708612] [RESET][spacemit_reset_set][373]:assert = 1, id = 59 \n", count=<optimized out>)
    at drivers/tty/serial/pxa_k1x.c:1724
torvalds#10 0xffffffff8004a34c in call_console_driver (dropped_text=0xffffffff81a68650 <dropped_text> "", len=69,
    text=0xffffffff81a68250 <text> "[   14.708612] [RESET][spacemit_reset_set][373]:assert = 1, id = 59 \n", con=0xffffffff81964c10 <serial_pxa_console>) at kernel/printk/printk.c:1942
torvalds#11 console_emit_next_record (con=con@entry=0xffffffff81964c10 <serial_pxa_console>, ext_text=<optimized out>, dropped_text=0xffffffff81a68650 <dropped_text> "", handover=0xffffffc80578baa7,
    text=0xffffffff81a68250 <text> "[   14.708612] [RESET][spacemit_reset_set][373]:assert = 1, id = 59 \n") at kernel/printk/printk.c:2731
torvalds#12 0xffffffff8004a49a in console_flush_all (handover=0xffffffc80578baa7, next_seq=<synthetic pointer>, do_cond_resched=false) at kernel/printk/printk.c:2793
torvalds#13 console_unlock () at kernel/printk/printk.c:2860
torvalds#14 0xffffffff8004b388 in vprintk_emit (facility=facility@entry=0, level=<optimized out>, level@entry=-1, dev_info=dev_info@entry=0x0, fmt=<optimized out>, args=<optimized out>)
    at kernel/printk/printk.c:2268
torvalds#15 0xffffffff8004b3ae in vprintk_default (fmt=<optimized out>, args=<optimized out>) at kernel/printk/printk.c:2279
torvalds#16 0xffffffff8004b646 in vprintk (fmt=fmt@entry=0xffffffff813be470 "\001\066[RESET][%s][%d]:assert = %d, id = %d \n", args=args@entry=0xffffffc80578bbd8) at kernel/printk/printk_safe.c:50
torvalds#17 0xffffffff80a880d6 in _printk (fmt=fmt@entry=0xffffffff813be470 "\001\066[RESET][%s][%d]:assert = %d, id = %d \n") at kernel/printk/printk.c:2289
torvalds#18 0xffffffff80a90bb6 in spacemit_reset_set (rcdev=rcdev@entry=0xffffffff81f563a8 <k1x_reset_controller+8>, id=id@entry=59, assert=assert@entry=true) at drivers/reset/reset-spacemit-k1x.c:373
torvalds#19 0xffffffff805823b6 in spacemit_reset_update (assert=true, id=59, rcdev=0xffffffff81f563a8 <k1x_reset_controller+8>) at drivers/reset/reset-spacemit-k1x.c:401
torvalds#20 spacemit_reset_update (assert=true, id=59, rcdev=0xffffffff81f563a8 <k1x_reset_controller+8>) at drivers/reset/reset-spacemit-k1x.c:387
torvalds#21 spacemit_reset_assert (rcdev=0xffffffff81f563a8 <k1x_reset_controller+8>, id=59) at drivers/reset/reset-spacemit-k1x.c:413
torvalds#22 0xffffffff8058158e in reset_control_assert (rstc=0xffffffd902b2f280) at drivers/reset/core.c:485
torvalds#23 0xffffffff807ccf96 in cpp_disable_clocks (cpp_dev=cpp_dev@entry=0xffffffd904cc9040) at drivers/media/platform/spacemit/camera/cam_cpp/k1x_cpp.c:960
torvalds#24 0xffffffff807cd0b2 in cpp_release_hardware (cpp_dev=cpp_dev@entry=0xffffffd904cc9040) at drivers/media/platform/spacemit/camera/cam_cpp/k1x_cpp.c:1038
torvalds#25 0xffffffff807cd990 in cpp_close_node (sd=<optimized out>, fh=<optimized out>) at drivers/media/platform/spacemit/camera/cam_cpp/k1x_cpp.c:1135
torvalds#26 0xffffffff8079525e in subdev_close (file=0xffffffd906645d00) at drivers/media/v4l2-core/v4l2-subdev.c:105
torvalds#27 0xffffffff8078e49e in v4l2_release (inode=<optimized out>, filp=0xffffffd906645d00) at drivers/media/v4l2-core/v4l2-dev.c:459
torvalds#28 0xffffffff80154974 in __fput (file=0xffffffd906645d00) at fs/file_table.c:320
torvalds#29 0xffffffff80154aa2 in ____fput (work=<optimized out>) at fs/file_table.c:348
torvalds#30 0xffffffff8002677e in task_work_run () at kernel/task_work.c:179
torvalds#31 0xffffffff800053b4 in resume_user_mode_work (regs=0xffffffc80578bee0) at ./include/linux/resume_user_mode.h:49
torvalds#32 do_work_pending (regs=0xffffffc80578bee0, thread_info_flags=<optimized out>) at arch/riscv/kernel/signal.c:478
torvalds#33 0xffffffff800039c6 in handle_exception () at arch/riscv/kernel/entry.S:374
Backtrace stopped: frame did not save the PC
(gdb) thread 1
[Switching to thread 1 (Thread 1)]
#0  0xffffffff80047e9c in arch_spin_lock (lock=lock@entry=0xffffffff81a57cd8 <g_cru_lock>) at ./include/asm-generic/spinlock.h:49
49      ./include/asm-generic/spinlock.h: No such file or directory.
(gdb) bt
#0  0xffffffff80047e9c in arch_spin_lock (lock=lock@entry=0xffffffff81a57cd8 <g_cru_lock>) at ./include/asm-generic/spinlock.h:49
#1  do_raw_spin_lock (lock=lock@entry=0xffffffff81a57cd8 <g_cru_lock>) at ./include/linux/spinlock.h:186
#2  0xffffffff80aa21ce in __raw_spin_lock_irqsave (lock=0xffffffff81a57cd8 <g_cru_lock>) at ./include/linux/spinlock_api_smp.h:111
#3  _raw_spin_lock_irqsave (lock=0xffffffff81a57cd8 <g_cru_lock>) at kernel/locking/spinlock.c:162
#4  0xffffffff8056c4cc in ccu_mix_disable (hw=0xffffffff81956858 <sdh2_clk+120>) at ./include/linux/spinlock.h:325
#5  0xffffffff80564832 in clk_core_disable (core=0xffffffd900529900) at drivers/clk/clk.c:1051
torvalds#6  clk_core_disable (core=0xffffffd900529900) at drivers/clk/clk.c:1031
torvalds#7  0xffffffff805648e6 in clk_core_disable_lock (core=0xffffffd900529900) at drivers/clk/clk.c:1063
torvalds#8  0xffffffff8056527e in clk_disable (clk=<optimized out>) at drivers/clk/clk.c:1084
torvalds#9  clk_disable (clk=clk@entry=0xffffffd904fafa80) at drivers/clk/clk.c:1079
torvalds#10 0xffffffff808bb898 in clk_disable_unprepare (clk=0xffffffd904fafa80) at ./include/linux/clk.h:1085
torvalds#11 0xffffffff808bb916 in spacemit_sdhci_runtime_suspend (dev=<optimized out>) at drivers/mmc/host/sdhci-of-k1x.c:1469
torvalds#12 0xffffffff8066e8e2 in pm_generic_runtime_suspend (dev=<optimized out>) at drivers/base/power/generic_ops.c:25
torvalds#13 0xffffffff80670398 in __rpm_callback (cb=cb@entry=0xffffffff8066e8ca <pm_generic_runtime_suspend>, dev=dev@entry=0xffffffd9018a2810) at drivers/base/power/runtime.c:395
torvalds#14 0xffffffff806704b8 in rpm_callback (cb=cb@entry=0xffffffff8066e8ca <pm_generic_runtime_suspend>, dev=dev@entry=0xffffffd9018a2810) at drivers/base/power/runtime.c:529
torvalds#15 0xffffffff80670bdc in rpm_suspend (dev=0xffffffd9018a2810, rpmflags=<optimized out>) at drivers/base/power/runtime.c:672
torvalds#16 0xffffffff806716de in pm_runtime_work (work=0xffffffd9018a2948) at drivers/base/power/runtime.c:974
torvalds#17 0xffffffff800236f4 in process_one_work (worker=worker@entry=0xffffffd9013ee9c0, work=0xffffffd9018a2948) at kernel/workqueue.c:2289
torvalds#18 0xffffffff80023ba6 in worker_thread (__worker=0xffffffd9013ee9c0) at kernel/workqueue.c:2436
torvalds#19 0xffffffff80028bb2 in kthread (_create=0xffffffd9017de840) at kernel/kthread.c:376
torvalds#20 0xffffffff80003934 in handle_exception () at arch/riscv/kernel/entry.S:249
Backtrace stopped: frame did not save the PC
(gdb)

Change-Id: Ia95b41ffd6c1893c9c5e9c1c9fc0c155ea902d2c
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kevin-zhm committed Dec 7, 2024
1 parent 2bfac76 commit e65ac1b
Showing 1 changed file with 0 additions and 2 deletions.
2 changes: 0 additions & 2 deletions drivers/reset/reset-spacemit-k1x.c
Original file line number Diff line number Diff line change
Expand Up @@ -370,8 +370,6 @@ static void spacemit_reset_set(struct reset_controller_dev *rcdev,
u32 value;
struct spacemit_reset *reset = to_spacemit_reset(rcdev);

LOG_INFO("assert = %d, id = %d ", assert, id);

value = spacemit_reset_read(reset, id);
if(assert == true) {
value &= ~ reset->signals[id].mask;
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