[U-Boot] [PATCH v3 4/4] usb: Change power-on / scanning timeout handling

[Stefan Roese <sr@denx.de>]

Hi Stephen,

On 15.03.2016 16:52, Stephen Warren wrote:
> On 03/15/2016 07:16 AM, Stefan Roese wrote:
>> Hi Stephen,
>>
>> On 14.03.2016 18:51, Stephen Warren wrote:
>>> On 03/14/2016 04:18 AM, Stefan Roese wrote:
>>>> This patch changes the USB port scanning procedure and timeout
>>>> handling in the following ways:
>>>  >..
>>>
>>> Tested-by: Stephen Warren <swarren@nvidia.com>
>>>
>>> (including some tests with a 7-port (i.e. 2 nested 4-port) USB hub maxed
>>> out with devices).
>>
>> Thanks for doing those tests on your platform. I'm interested, how
>> big the time difference between stock U-Boot and the patched
>> version is though. Could you please post those numbers once for
>> reference, if its not too much trouble?
> 
> It looks like ~17s for v2016.01, and ~6s for u-boot/master from 
> yesterday plus these patches, with the following configuration:
> 
> Tegra124 (Jetson TK1) # usb tree
> USB device tree:
>    1  Hub (480 Mb/s, 0mA)
>       u-boot EHCI Host Controller
> 
>    1  Hub (480 Mb/s, 0mA)
>    |  u-boot EHCI Host Controller
>    |
>    +-2  Hub (480 Mb/s, 100mA)
>      |   USB2.0 Hub
>      |
>      +-3  Hub (480 Mb/s, 100mA)
>      | |   USB2.0 Hub
>      | |
>      | +-6  Mass Storage (480 Mb/s, 2mA)
>      | |    Sunplus Innovation Technology. USB to Serial-ATA bridge 
> FF980813AF0000000000005FF16BFF
>      | |
>      | +-7  Mass Storage (480 Mb/s, 100mA)
>      | |    Generic    Mass Storage Device 00000000000006
>      | |
>      | +-8  Human Interface (1.5 Mb/s, 70mA)
>      | |    LITEON Technology USB Multimedia Keyboard
>      | |
>      | +-9  Human Interface (1.5 Mb/s, 100mA)
>      |      Microsoft Microsoft IntelliMouse? Explore
>      |
>      +-4  Vendor specific (480 Mb/s, 250mA)
>      |    ASIX Elec. Corp. AX88x72A 000001
>      |
>      +-5  Mass Storage (480 Mb/s, 200mA)
>           SanDisk Extreme AA010114140242512567

Thanks.

I'm wondering why your configuration takes that much longer to
scan than mine (x86 platform). My USB configuration is not
that different:

=> time usb start
starting USB...
USB0:   USB EHCI 1.00
scanning bus 0 for devices... 9 USB Device(s) found

time: 1.815 seconds
=> usb tree
USB device tree:
  1  Hub (480 Mb/s, 0mA)
  |  u-boot EHCI Host Controller 
  |
  +-2  Hub (480 Mb/s, 0mA)
    |
    +-3  Hub (480 Mb/s, 100mA)
    | |
    | +-7  Hub (12 Mb/s, 100mA)
    |    
    +-4  Hub (480 Mb/s, 0mA)
    | |
    | +-8  Mass Storage (480 Mb/s, 200mA)
    | |    Kingston DataTraveler 2.0 50E549C688C4BE7189942766
    | |  
    | +-9  Mass Storage (480 Mb/s, 98mA)
    |      USBest Technology USB Mass Storage Device 09092207fbf0c4
    |    
    +-5  Mass Storage (480 Mb/s, 200mA)
    |    6989 Intenso Alu Line EE706F5E
    |  
    +-6  Mass Storage (480 Mb/s, 200mA)
         JetFlash Mass Storage Device 3281440601


And I'm down to less than 2 seconds scanning time. Perhaps
worth digging into at some point. But lets get this version
upstreamed first.

Thanks,
Stefan