69eea7c01a
EHCI controllers see transfers as a queue of transfer descriptors (qTDs), each of which can represent an aligned area of up to 20KB. Each qTD is processed separately, which means that a single USB packet cannot span multiple qTDs. While this should not be a problem according to the specification, some USB storage devices seem to get confused when a packet in the middle of a transfer is smaller than the maximum packet size (512 bytes) due to falling on a qTD boundary. This patch aligns the total transfer length per qTD to 512 bytes to avoid that problem (any excess bytes will simply roll over to the next qTD). Change-Id: I0b5db07507699a3861b30c1a5ee774c45dda7fdd Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: http://review.coreboot.org/2651 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi <patrick@georgi-clan.de> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Ronald G. Minnich <rminnich@gmail.com> |
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| bayou | ||
| coreinfo | ||
| external | ||
| libpayload | ||
| nvramcui | ||
| tianocoreboot | ||