the following patch was just integrated into master: commit 49ba28339087cb1057fbb12071a0981013a88e55 Author: Julius Werner jwerner@chromium.org Date: Thu Sep 26 15:13:44 2013 -0700
libpayload: xhci: Ensure to reset dequeue pointer on stopped endpoints
This patch fixes a bug in the XHCI stack that occurs when a multi-TRB TD times out before the last TRB is processed. The driver will correctly issue a Stop Endpoint command in that case, but the xHC will still preserve the transfer state and just pick up right after that on the next doorbell ring. It will then process the leftover TRBs from the old TD the next time a transfer is issued. (cf. XHCI 4.6.9)
We fix this by changing the existing xhci_reset_endpoint() calls in transfer functions to not only trigger on Halted (2) and Error (4), but also on Stopped (3). That function will not actually issue a Reset Endpoint command in this case, but it will nuke the whole transfer ring and issue a Set TR Dequeue Pointer command, which is sufficient (though slightly overkill) to solve our problem.
Change-Id: I3abbe30ff9d4911a8af1f792324e018d427019e8 Signed-off-by: Julius Werner jwerner@chromium.org Reviewed-on: https://chromium-review.googlesource.com/170833 Reviewed-by: Ronald Minnich rminnich@chromium.org Reviewed-by: Kees Cook keescook@chromium.org (cherry picked from commit f12424af0e29ac12963e8e5a7970fadcc0bb6cee) Signed-off-by: Isaac Christensen isaac.christensen@se-eng.com Reviewed-on: http://review.coreboot.org/6787 Reviewed-by: Stefan Reinauer stefan.reinauer@coreboot.org Tested-by: build bot (Jenkins)
See http://review.coreboot.org/6787 for details.
-gerrit