diff options
author | Yidi Lin <yidi.lin@mediatek.com> | 2015-05-07 15:36:04 +0800 |
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committer | Patrick Georgi <pgeorgi@google.com> | 2015-06-03 11:11:59 +0200 |
commit | d42ee150a0330f22986ad7237c9e70cebd9d995c (patch) | |
tree | 67e64639a41e020e1d7377a579085b3d59e2137b /src/cpu | |
parent | 08e30134900c1c8f169668e8b5b2b90254996c9a (diff) |
libpayload: usb: Support MTK xHCI host controller
1. There is a mis-understanding to calculate the value of TD Size
in Normal TRB. For MTK's xHCI controller it defines a number of
packets that remain to be transferred for a TD after processing
all Max packets in all previous TRBs, that means don't include the
current TRB's.
2. To minimize the scheduling effort for synchronous endpoints in xHC,
the MTK architecture defines some extra SW scheduling parameters for
HW. According to these parameters provided by SW, the xHC can easily
decide whether a synchronous endpoint should be scheduled in a specific
uFrame. The extra SW scheduling parameters are put into reserved DWs
in Slot and Endpoint Context. But in coreboot synchronous transfer can
be ignored, so only two fields are set to a default value 1 to support
bulk and interrupt transfers, and others are set to zero.
3. For control transfer, it is better to read back doorbell register or add
a memory barrier after ringing the doorbell to flush posted write.
Otherwise the first command will be aborted on MTK's xHCI controller.
4. Before send commands to a port, the Port Power in PORTSC register should
be set to 1 on MTK's xHCI so a hook function of enable_port in
generic_hub_ops_t struct is provided.
Change-Id: Ie8878b50c048907ebf939b3f6657535a54877fde
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 738609c11f16264c6e6429d478b2040cb391fe41
Original-Change-Id: Id9156892699e2e42a166c77fbf6690049abe953b
Original-Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/265362
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Original-Commit-Queue: Yidi Lin <yidi.lin@mediatek.com>
Original-Tested-by: Yidi Lin <yidi.lin@mediatek.com>
Reviewed-on: http://review.coreboot.org/10389
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Tested-by: build bot (Jenkins)
Diffstat (limited to 'src/cpu')
0 files changed, 0 insertions, 0 deletions