Jann Horn 7dbdb53d72 USB: early: Handle AMD's spec-compliant identifiers, too ... This fixes a bug that causes the USB3 early console to freeze after printing a single line on AMD machines because it can't parse the Transfer TRB properly. The spec at https://www.intel.com/content/dam/www/public/us/en/documents/technical-specifications/extensible-host-controler-interface-usb-xhci.pdf says in section "4.5.1 Device Context Index" that the Context Index, also known as Endpoint ID according to section "1.6 Terms and Abbreviations", is normally computed as `DCI = (Endpoint Number * 2) + Direction`, which matches the current definitions of XDBC_EPID_OUT and XDBC_EPID_IN. However, the numbering in a Debug Capability Context data structure is supposed to be different: Section "7.6.3.2 Endpoint Contexts and Transfer Rings" explains that a Debug Capability Context data structure has the endpoints mapped to indices 0 and 1. Change XDBC_EPID_OUT/XDBC_EPID_IN to the spec-compliant values, add XDBC_EPID_OUT_INTEL/XDBC_EPID_IN_INTEL with Intel's incorrect values, and let xdbc_handle_tx_event() handle both. I have verified that with this patch applied, the USB3 early console works on both an Intel and an AMD machine. Fixes: aeb9dd1de9 ("usb/early: Add driver for xhci debug capability") Cc: stable@vger.kernel.org Signed-off-by: Jann Horn <jannh@google.com> Link: https://lore.kernel.org/r/20200401074619.8024-1-jannh@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-04-16 14:46:00 +02:00
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ehci-dbgp.c	drivers: usb: early: clean up indentation, remove extraneous tabs	2018-11-23 16:13:14 +01:00
Makefile	USB: add SPDX identifiers to all remaining Makefiles	2017-11-07 15:53:48 +01:00
xhci-dbc.c	USB: early: Handle AMD's spec-compliant identifiers, too	2020-04-16 14:46:00 +02:00
xhci-dbc.h	USB: early: Handle AMD's spec-compliant identifiers, too	2020-04-16 14:46:00 +02:00