[bug] can't start watchdog on RK3288

[Peter Robinson]

Hi,

> I have a bug to report. I tried starting the watchdog on Asus TinkerBoard S
> (Rockchip RK3288), but it's not working. I investigated a little bit. Here's
> what I found so far:

What version of U-Boot is this? Does the watchdog work in Linux?

> => wdt dev watchdog at ff800000
> drivers/core/ofnode.c:417-ofnode_read_u32_index() ofnode_read_u32_index: timeout-sec: (not found)
> drivers/core/ofnode.c:417-ofnode_read_u32_index() ofnode_read_u32_index: hw_margin_ms: (not found)
> drivers/core/ofnode.c:525-    ofnode_read_bool() ofnode_read_bool: u-boot,noautostart: false
> drivers/core/ofnode.c:525-    ofnode_read_bool() ofnode_read_bool: u-boot,autostart: false
> drivers/core/ofnode.c:540-    ofnode_read_prop() ofnode_read_prop: assigned-clock-rates: <not found>
> drivers/core/uclass.c:546-uclass_get_device_by_ofnode() Looking for clock-controller at ff760000
> drivers/core/uclass.c:397-uclass_find_device_by_ofnode() Looking for clock-controller at ff760000
> drivers/core/uclass.c:406-uclass_find_device_by_ofnode()       - checking oscillator
> drivers/core/uclass.c:406-uclass_find_device_by_ofnode()       - checking clock-controller at ff760000
> drivers/core/uclass.c:416-uclass_find_device_by_ofnode()    - result for clock-controller at ff760000: clock-controller at ff760000 (ret=0)
> drivers/core/uclass.c:549-uclass_get_device_by_ofnode()    - result for clock-controller at ff760000: clock-controller at ff760000 (ret=0)
> Can't get the watchdog timer: watchdog at ff800000
>
> It seems that the error is generated in designware_wdt_probe(), after
> clk_enable(). Function clk_enable() runs on branch CLK_CCF=false. It returns
> error from ops->enable. Struct ops is defined by driver: rockchip_rk3288_cru,
> in drivers/clk/rockchip/clk_rk3288.c, but it doesn't have a .enable or
> .disable component, so there is no ops->enable.
>
> The solution to this one would probably be a stub for .enable. AFAIK, it's
> always enabled.
>
> I also tried to enable CLK_CCF (drivers from Linux tree), selecting the
> watchdog works, but if I try to start it, the board immediately resets.
> I have no ideea how to troubleshoot this one.
>
> Thanks.
> Marius
>