6.10-stable review patch. If anyone has any objections, please let me know.
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From: Pawel Laszczak pawell@cadence.com
commit 740f2e2791b98e47288b3814c83a3f566518fed2 upstream.
Stop Endpoint command on LINK TRB with TC bit set to 1 causes that internal cycle bit can have incorrect state after command complete. In consequence empty transfer ring can be incorrectly detected when EP is resumed. NOP TRB before LINK TRB avoid such scenario. Stop Endpoint command is then on NOP TRB and internal cycle bit is not changed and have correct value.
Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver") cc: stable@vger.kernel.org Signed-off-by: Pawel Laszczak pawell@cadence.com Reviewed-by: Peter Chen peter.chen@kernel.org Link: https://lore.kernel.org/r/PH7PR07MB953878279F375CCCE6C6F40FDD8E2@PH7PR07MB95... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/cdns3/cdnsp-gadget.h | 3 +++ drivers/usb/cdns3/cdnsp-ring.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 31 insertions(+)
--- a/drivers/usb/cdns3/cdnsp-gadget.h +++ b/drivers/usb/cdns3/cdnsp-gadget.h @@ -811,6 +811,7 @@ struct cdnsp_stream_info { * generate Missed Service Error Event. * Set skip flag when receive a Missed Service Error Event and * process the missed tds on the endpoint ring. + * @wa1_nop_trb: hold pointer to NOP trb. */ struct cdnsp_ep { struct usb_ep endpoint; @@ -838,6 +839,8 @@ struct cdnsp_ep { #define EP_UNCONFIGURED BIT(7)
bool skip; + union cdnsp_trb *wa1_nop_trb; + };
/** --- a/drivers/usb/cdns3/cdnsp-ring.c +++ b/drivers/usb/cdns3/cdnsp-ring.c @@ -1905,6 +1905,23 @@ int cdnsp_queue_bulk_tx(struct cdnsp_dev return ret;
/* + * workaround 1: STOP EP command on LINK TRB with TC bit set to 1 + * causes that internal cycle bit can have incorrect state after + * command complete. In consequence empty transfer ring can be + * incorrectly detected when EP is resumed. + * NOP TRB before LINK TRB avoid such scenario. STOP EP command is + * then on NOP TRB and internal cycle bit is not changed and have + * correct value. + */ + if (pep->wa1_nop_trb) { + field = le32_to_cpu(pep->wa1_nop_trb->trans_event.flags); + field ^= TRB_CYCLE; + + pep->wa1_nop_trb->trans_event.flags = cpu_to_le32(field); + pep->wa1_nop_trb = NULL; + } + + /* * Don't give the first TRB to the hardware (by toggling the cycle bit) * until we've finished creating all the other TRBs. The ring's cycle * state may change as we enqueue the other TRBs, so save it too. @@ -1999,6 +2016,17 @@ int cdnsp_queue_bulk_tx(struct cdnsp_dev send_addr = addr; }
+ if (cdnsp_trb_is_link(ring->enqueue + 1)) { + field = TRB_TYPE(TRB_TR_NOOP) | TRB_IOC; + if (!ring->cycle_state) + field |= TRB_CYCLE; + + pep->wa1_nop_trb = ring->enqueue; + + cdnsp_queue_trb(pdev, ring, 0, 0x0, 0x0, + TRB_INTR_TARGET(0), field); + } + cdnsp_check_trb_math(preq, enqd_len); ret = cdnsp_giveback_first_trb(pdev, pep, preq->request.stream_id, start_cycle, start_trb);