[RFT PATCH v1 0/5] usb: Improve robustness of ehci-hcd controller operation

Lukasz Majewski lukma at denx.de
Mon Mar 23 23:11:03 CET 2020

Hi Tom,

> On Sun, Mar 22, 2020 at 02:00:26PM +0100, Lukasz Majewski wrote:
> > This patch set is rather a request for testing (and a starting
> > point for the discussion), as it may improve the robustness of USB
> > with some pendrives - and yes sacrifice some performance for
> > reliability. The previous version of this patch:
> > https://patchwork.ozlabs.org/patch/1244928/ fixed issue for some
> > network USB adapters and improved stability on TI boards. This
> > patch also provides very detailed explanation of the problem in the
> > commit message.
> > 
> > With the async support patch applied (
> > SHA1: 02b0e1a36c5bc20174299312556ec4e266872bd6 ), the qhtoken
> > variable has value 0x00 when token shows errors. As a result the
> > error handling path is not executed. This looks like some
> > missing/broken cache flushing - for easier bisecting this patch has
> > been reverted for now  
> Note that while the original patch returned USB ethernet on the
> Beagleboard to a functional state with this series applied it's back
> to non-functional.

Thanks for testing.

The _only_ difference between the first version of this patch and this
one is the lack of dynamic reduction of transfer size for the latter.
The former reduces the transfer size to 64 blocks (instead of default
240). And with 64 blocks it retries two times the transmission.

Best regards,

Lukasz Majewski


DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma at denx.de
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 488 bytes
Desc: OpenPGP digital signature
URL: <https://lists.denx.de/pipermail/u-boot/attachments/20200323/3c9e4559/attachment.sig>

More information about the U-Boot mailing list