[U-Boot] [PATCH] [MPC837x v2] Make it work again with USB.

[Andre Schwarz <andre.schwarz@matrix-vision.de>]

Kim,

finally found some time to re-work my 8377 board code for submission.

sorry to bother you again, but I again stumbled over the discussed USB 
init issue :
>>> nack, 837x has a usb controller at IMMR+0x23000.
>> yes - but offset 0x00-0xff is explicitly reserved regarding to the manual.
>> Don't know whether it is a "should not" or "must not be touched".
>>   
>> All I can see is a CPU hang with arbiter event register reporting a timeout on
>> 0xe0023000.
>>   
>>
>>    Check to see whether there is an invalid USB clock setting in the SCCR? 
>> All clocks are turned on except SEC and 2nd TSEC.
>>   
>> After all USB is running fine with this patch, i.e. there can hardly be a
>> missing clock.
>>
>>
>> Please re-think you NAK.
> afaik, 834x and 837x don't have any special USB settings in common, so,
> this patch, at least in it's current form, is not on.
>
> 0xe0023500 should be the address of the config register being accessed
> here; please check the code isn't accessing 0xe0023000, as you mention
> above.

ok - this was some kind of misunderstanding.
ehci regs are based at immr + 0x23000 with the "config" pointing to 
offset 0x500 inside ehci.
This looks sane to me.

> If that's correct, try something like the following so we can determine
> what setting the USB controller didn't agree with:
>
> diff --git a/arch/powerpc/cpu/mpc83xx/cpu_init.c b/arch/powerpc/cpu/mpc83xx/cpu_init.c
> index 7a1cae7..cbc4157 100644
> --- a/arch/powerpc/cpu/mpc83xx/cpu_init.c
> +++ b/arch/powerpc/cpu/mpc83xx/cpu_init.c
> @@ -332,7 +332,7 @@ void cpu_init_f (volatile immap_t * im)
>   	struct usb_ehci *ehci = (struct usb_ehci *)CONFIG_SYS_FSL_USB_ADDR;
>
>   	/* Configure interface. */
> -	setbits_be32(&ehci->control, REFSEL_16MHZ | UTMI_PHY_EN);
MPC837x has only 2 working bits inside the control register :

Bit29: USB_EN -> should be set to 1 before USB can be used.
Bit31: ULPI_INT_EN -> enables an ULPI wake-up irq.

Both "REFSEL_16MHZ" and "UTMI_PHY_EN" are completely out of scope for 
MPC837x.

> +	setbits_be32(&ehci->control, 0);
>
>   	/* Wait for clock to stabilize */
This loop never returns on MPC837x because "PHY_CLK_VALID" isn't valid.
>   	do {    temp = __raw_readl(&ehci->control);
>                  udelay(1000);
>          } while (!(temp&  PHY_CLK_VALID));
>
I still wonder how there can be a single working MPC837x board with 
CONFIG_USB_EHCI_FSL set.

Some pending patches on your side ?
What kind of patch might get an ACK from your side ?

-- 

Regards,
Andre



MATRIX VISION GmbH, Talstrasse 16, DE-71570 Oppenweiler
Registergericht: Amtsgericht Stuttgart, HRB 271090
Geschaeftsfuehrer: Gerhard Thullner, Werner Armingeon, Uwe Furtner