[U-Boot] [PATCH] arm64: allwinner: a64: Disable ehci1 and ohci1 for bananapi, nanopi

[Marek Vasut]

On 07/02/2018 10:53 PM, Jagan Teki wrote:
> During usb shutdown or 'usb reset' all the necessary clocks
> on the specific controller will disable. Usually this shutdown
> happen during U-Boot proper handoff to Linux.

No, 'usb reset' can be triggered by the user any time.

> There is an issue in Allwinner A64, is during OHCI1 shutdown
> the controller is unable to access the register space
> so the Linux boot hangs at this place.

This doesn't make any sense, Linux should enable the necessary clock
before accessing any controller registers, unless there is a bug in Linux.

> This particular condition occur when we enable both the
> controllers, so this patch will disable OHCI1 and EHCI1 for
> bananapi-m64 and nanopi-a64 boards. It will re-enable the same
> once the issue got fixed.
> 
> Log:
> => usb reset
> resetting USB...
> 
> PHY0: mask = 0x101, usb_clk_cfg = 0x30202
> sunxi_musb_exit: ahb_gate0  = 0x33004540, reset0_cfg = 0x33004540
> EHCI failed to shut down host controller.
> ehci_usb_remove: ahb_gate0  = 0x32004540, reset0_cfg = 0x32004540
> ohci_usb_remove: ahb_gate0  = 0x22004540, reset0_cfg = 0x22004540
> ohci_usb_remove: mask = 0x10000, usb_clk_cfg = 0x20202
> 
> PHY1: mask = 0x202, usb_clk_cfg = 0x0
> ehci_usb_remove: ahb_gate0  = 0x20004540, reset0_cfg = 0x20004540

Why is this usb reset so noisy ?

> << hang here >>

Please fix this properly, this patch is pure attempt to hide a bug.
NAK from me.

> Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
> ---
> Note:
> Reason for this patch, since we have week to release.
> Hopefully this will fix in coming releases.
> 
> debugging:
> =========
> Allwinner A64 share common PHY between OTG & Host controller,
> so it's job of OTG to shutdown the controller. But unfortunately
> there is no shutdown call from command(usb reset) or handoff code
> for OTG controller in gadget mode, UCLASS_USB_DEV_GENERIC.
> 
> So, we added glue code to shutdown musb, and it's shutdown
> propely.
> 
> Then we found an issue of disabling OHCI1 gate clock
> during OHCI0 shutdown. ohci driver is trying to clear BIT(16)
> for OHCI0, but it also clears BIT(17), which is for OHCI1.
> fortunately this is resolved when we clear usb_clk_cfg after
> reset0_cfg and ahb_gate0, but OHCI1 still hang.
> 
> so, we still need to figure it out. Any help appreciated.
> 
> Above log reproduced on
> https://github.com/amarula/u-boot-amarula/tree/sun-dev
> repo since it has some fixes and improvements wrt mainline code.
> 
>  arch/arm/dts/sun50i-a64-bananapi-m64.dts | 8 --------
>  arch/arm/dts/sun50i-a64-nanopi-a64.dts   | 8 --------
>  2 files changed, 16 deletions(-)
> 
> diff --git a/arch/arm/dts/sun50i-a64-bananapi-m64.dts b/arch/arm/dts/sun50i-a64-bananapi-m64.dts
> index dcde4a4881..32e3402998 100644
> --- a/arch/arm/dts/sun50i-a64-bananapi-m64.dts
> +++ b/arch/arm/dts/sun50i-a64-bananapi-m64.dts
> @@ -72,10 +72,6 @@
>  	status = "okay";
>  };
>  
> -&ehci1 {
> -	status = "okay";
> -};
> -
>  &i2c1 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&i2c1_pins>;
> @@ -120,10 +116,6 @@
>  	status = "okay";
>  };
>  
> -&ohci1 {
> -	status = "okay";
> -};
> -
>  &uart0 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&uart0_pins_a>;
> diff --git a/arch/arm/dts/sun50i-a64-nanopi-a64.dts b/arch/arm/dts/sun50i-a64-nanopi-a64.dts
> index 778636c73a..ba36944caa 100644
> --- a/arch/arm/dts/sun50i-a64-nanopi-a64.dts
> +++ b/arch/arm/dts/sun50i-a64-nanopi-a64.dts
> @@ -70,10 +70,6 @@
>  	status = "okay";
>  };
>  
> -&ehci1 {
> -	status = "okay";
> -};
> -
>  /* i2c1 connected with gpio headers like pine64, bananapi */
>  &i2c1 {
>  	pinctrl-names = "default";
> @@ -100,10 +96,6 @@
>  	status = "okay";
>  };
>  
> -&ohci1 {
> -	status = "okay";
> -};
> -
>  &uart0 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&uart0_pins_a>;
> 


-- 
Best regards,
Marek Vasut