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authorYidi Lin <yidi.lin@mediatek.com>2015-05-07 15:36:04 +0800
committerPatrick Georgi <pgeorgi@google.com>2015-06-03 11:11:59 +0200
commitd42ee150a0330f22986ad7237c9e70cebd9d995c (patch)
tree67e64639a41e020e1d7377a579085b3d59e2137b /src/mainboard/via/vt8454c
parent08e30134900c1c8f169668e8b5b2b90254996c9a (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)
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