[U-Boot] [PATCH RFC] OMAP5: uEVM: Enable USB EHCI functionality (preliminary, not tested)

[Lubomir Popov]

Hi Gilles,

> On 05/16/2013 10:39 AM, Lubomir Popov wrote:
>
>> Hi Gilles,
>>
>> On 16/05/13 01:31, Gilles Chanteperdrix wrote:
>>> On 05/15/2013 05:55 PM, Lubomir Popov wrote:
>>>
>>>> Prerequisites: appropriate patches to the USB EHCI and Eth
>>>> drivers, and to the OMAP5 clock register definitions.
>>>
>>>
>>> Hi Lubomir,
>>>
>>> I have been trying to get the USB working on omap5 uEVM yesterday. In
>>> addition to your code, I added the changes necessary to pinmux the 79
>>> and 80 GPIOS correctly, but it does not seem to work. I suspect there
>>> is
>>> something else missing than simply USB specific bits, because when the
>>> ethernet phy is supposedly out of reset, the ethernet leds keep turned
>>> off. I was thinking about checking the PMIC registers.
>> PMIC wouldn't be related.
>
>
> Hi,
>
> My idea was that if the ethernet chip does not power up, maybe it is
> because some LDO or SMPS needs to be powered on. The board documentation
> says for some LDOs that they are enabled on boot and does not say for
> others, so that may be because they need to be enabled.
Both USB devices are powered by VCC_3V3_MAIN, provided by an external SMPS
chip (U3). With the default configuration of the uEVM, this SMPS turns on
whenever DC wall power is present; the other option - control by the PMIC
SYSEN1 output, has no relation to software as well (SYSEN1 is driven by
the PMIC power-on/off sequencer, which is burnt into the PMIC EPROM. Upon
power-on it goes high at the very beginning of the sequence). So,
unfortunately, this could not be the cause.
Regarding the Ethernet LEDs, as far as I remember, they didn't light up at
all, although Ethernet worked. The smsc95xx driver in u-boot supports the
LAN9730 in compatibility mode and probably does not setup LED operation
properly.
>
>>
>> Did you pull the current u-boot master and then apply the following
>> patches
>> before testing? Eager to know ;)
>>
>> http://patchwork.ozlabs.org/patch/232742/
>> http://patchwork.ozlabs.org/patch/244100/
>
>
> I was working with u-boot-ti master, applied all the patches, and it
> still does not seem to work. I just tried the u-boot master branch but
> it fails to compile for omap5_uevm.
I think mainline u-boot master still lacks another vital patch for OMAP5
USB, which has been applied to u-boot-ti only (this is commit
2bcc785a1e8ffd3783c2116837fb4b4866a70cef). So please stay with the ti
branch for now.
Don't know what to say; it's a pity that I don't have the hardware at hand.
One more thing that I would suggest to try: remove the patch from ehci-hcd.c
that calls the HSIC device reset function for OMAP5. The essence is one
line, a function call:

omap5_ehci_hsic_reset_device(le16_to_cpu(req->index));

Just comment it out. It is fairly possible that on ES2.0 this workaround is
not needed anymore (although I don't recall anything on the subject in the
Silicon Errata docs). I have tested on ES1.0 only, so it has to be
verified that this patch doesn't have a negative impact on ES2.0.
>
> Regards.
>
> --
>                                                                 Gilles.
>
Best regards,
Lubo