[PATCH] drm: meson_drv add shutdown function

[Kevin Hilman]

Artem Lapkin <email2tema at gmail.com> writes:

> Problem: random stucks on reboot stage about 1/20 stuck/reboots
> // debug kernel log
> [    4.496660] reboot: kernel restart prepare CMD:(null)
> [    4.498114] meson_ee_pwrc c883c000.system-controller:power-controller: shutdown begin
> [    4.503949] meson_ee_pwrc c883c000.system-controller:power-controller: shutdown domain 0:VPU...
> ...STUCK...
>
> Solution: add shutdown function to meson_drm driver 
> // debug kernel log
> [    5.231896] reboot: kernel restart prepare CMD:(null)
> [    5.246135] [drm:meson_drv_shutdown]
> ...
> [    5.259271] meson_ee_pwrc c883c000.system-controller:power-controller: shutdown begin
> [    5.274688] meson_ee_pwrc c883c000.system-controller:power-controller: shutdown domain 0:VPU...
> [    5.338331] reboot: Restarting system
> [    5.358293] psci: PSCI_0_2_FN_SYSTEM_RESET reboot_mode:0 cmd:(null)
> bl31 reboot reason: 0xd
> bl31 reboot reason: 0x0
> system cmd  1.
> ...REBOOT...
>
> Tested: on VIM1 VIM2 VIM3 VIM3L khadas sbcs - 1000+ successful reboots
> and Odroid boards, WeTek Play2 (GXBB)
>
> Tested-by: Christian Hewitt <christianshewitt at gmail.com>
> Signed-off-by: Artem Lapkin <art at khadas.com>

Acked-by: Kevin Hilman <khilman at baylibre.com>