clk: meson: change usleep_range() to udelay() for atomic context
The function meson_clk_pll_enable() can be invoked under the enable_lock spinlock from the clk core logic, which risks a kernel panic during the usleep_range() call: BUG: scheduling while atomic: kworker/u4:2/36/0x00000002 Modules linked in: g_ffs usb_f_fs libcomposite CPU: 1 PID: 36 Comm: kworker/u4:2 Not tainted 6.4.0-rc5 #273 Workqueue: events_unbound async_run_entry_fn Call trace: dump_backtrace+0x9c/0x128 show_stack+0x20/0x38 dump_stack_lvl+0x48/0x60 dump_stack+0x18/0x28 __schedule_bug+0x58/0x78 __schedule+0x828/0xa88 schedule+0x64/0xd8 schedule_hrtimeout_range_clock+0xd0/0x208 schedule_hrtimeout_range+0x1c/0x30 usleep_range_state+0x6c/0xa8 meson_clk_pll_enable+0x1f4/0x310 clk_core_enable+0x78/0x200 clk_core_enable+0x58/0x200 clk_core_enable+0x58/0x200 clk_core_enable+0x58/0x200 clk_enable+0x34/0x60 So it is required to use the udelay() function instead of usleep_range() for the atomic context safety. Fixes: b6ec400a ("clk: meson: introduce new pll power-on sequence for A1 SoC family") Reported-by: Jan Dakinevich <yvdakinevich@sberdevices.ru> Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru> Link: https://lore.kernel.org/r/20230704215404.11533-1-ddrokosov@sberdevices.ru Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
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