diff options
| author | Jann Horn <jannh@google.com> | 2020-04-01 09:46:19 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-04-16 14:46:00 +0200 |
| commit | 7dbdb53d72a51cea9b921d9dbba54be00752212a (patch) | |
| tree | 1a37c38cd2541ae73f9075ef1c8781e650d9225c /drivers/usb/early/xhci-dbc.c | |
| parent | 056ad39ee9253873522f6469c3364964a322912b (diff) | |
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: aeb9dd1de98c ("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>
Diffstat (limited to 'drivers/usb/early/xhci-dbc.c')
| -rw-r--r-- | drivers/usb/early/xhci-dbc.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/usb/early/xhci-dbc.c b/drivers/usb/early/xhci-dbc.c index 971c6b92484a..171280c80228 100644 --- a/drivers/usb/early/xhci-dbc.c +++ b/drivers/usb/early/xhci-dbc.c @@ -728,19 +728,19 @@ static void xdbc_handle_tx_event(struct xdbc_trb *evt_trb) case COMP_USB_TRANSACTION_ERROR: case COMP_STALL_ERROR: default: - if (ep_id == XDBC_EPID_OUT) + if (ep_id == XDBC_EPID_OUT || ep_id == XDBC_EPID_OUT_INTEL) xdbc.flags |= XDBC_FLAGS_OUT_STALL; - if (ep_id == XDBC_EPID_IN) + if (ep_id == XDBC_EPID_IN || ep_id == XDBC_EPID_IN_INTEL) xdbc.flags |= XDBC_FLAGS_IN_STALL; xdbc_trace("endpoint %d stalled\n", ep_id); break; } - if (ep_id == XDBC_EPID_IN) { + if (ep_id == XDBC_EPID_IN || ep_id == XDBC_EPID_IN_INTEL) { xdbc.flags &= ~XDBC_FLAGS_IN_PROCESS; xdbc_bulk_transfer(NULL, XDBC_MAX_PACKET, true); - } else if (ep_id == XDBC_EPID_OUT) { + } else if (ep_id == XDBC_EPID_OUT || ep_id == XDBC_EPID_OUT_INTEL) { xdbc.flags &= ~XDBC_FLAGS_OUT_PROCESS; } else { xdbc_trace("invalid endpoint id %d\n", ep_id); |