On Sat, 15 Feb 2020 at 04:34, Anatolij Gustschin <ag...@denx.de> wrote: > > Currently when booting the kernel on i.MX8 U-Boot hangs in an > endless loop when switching off dma, connectivity or lsio power > domains during device removal. It hapens first when removing > gpio0 (gpio@5d080000) device, here its power domain device > 'lsio_gpio0' is obtained for switching off power. Since the > obtained 'lsio_gpio0' device is removed afterwards, its power > domain is also switched off and here the parent power domain > device 'lsio_power_domain' is optained for switching off the > power. Thereafter, when the obtained 'lsio_power_domain' is > removed, device_remove() removes its first child 'lsio_gpio0'. > During this child removal the 'lsio_power_domain' device is > obtained again for switching and when removing it later, > the same child removal is repeated, so we are stuck in an > endless loop. Below is a snippet from dm tree on i.MX8QXP > for better illustration of the DM devices relationship: > > Class Index Probed Driver Name > ----------------------------------------------------------- > root 0 [ + ] root_driver root_driver > ... > simple_bus 0 [ + ] generic_simple_bus |-- imx8qx-pm > power_doma 0 [ + ] imx8_power_domain | |-- lsio_power_domain > power_doma 1 [ + ] imx8_power_domain | | |-- lsio_gpio0 > power_doma 2 [ + ] imx8_power_domain | | |-- lsio_gpio1 > > Do not remove a power domain device if it is a parent of the > currently controlled device. > > Fixes: 52edfed65de9 ("dm: core: device: switch off power domain after device > removal") > Signed-off-by: Anatolij Gustschin <ag...@denx.de> > Reported-by: Oliver Graute <oliver.gra...@gmail.com> > Reported-by: Fabio Estevam <feste...@gmail.com> > > --- > drivers/power/domain/power-domain-uclass.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+)
Can we have a sandbox test for this case? Reviewed-by: Simon Glass <s...@chromium.org> Regards, Simon