diff options
| -rw-r--r-- | src/portable/mentor/musb/dcd_musb.c | 59 |
1 files changed, 35 insertions, 24 deletions
diff --git a/src/portable/mentor/musb/dcd_musb.c b/src/portable/mentor/musb/dcd_musb.c index 86ae3ae9a..2c31e3b2f 100644 --- a/src/portable/mentor/musb/dcd_musb.c +++ b/src/portable/mentor/musb/dcd_musb.c @@ -86,7 +86,8 @@ enum { PIPE0_STATE_DATA_OUT, // DATA OUT stage PIPE0_STATE_STATUS_IN, // STATUS IN — device sends IN-ZLP; awaits send-ACK IRQ PIPE0_STATE_STATUS_OUT, // post-DATAEND, neither edpt0_xfer(STATUS OUT) nor confirmation IRQ has happened yet - PIPE0_STATE_STATUS_OUT_PENDING, // one of {edpt0_xfer(STATUS OUT), confirmation IRQ} has happened; the other fires xfer_complete + PIPE0_STATE_STATUS_OUT_PENDING_XFER, // edpt0_xfer(STATUS OUT) called first; the confirmation IRQ fires xfer_complete + PIPE0_STATE_STATUS_OUT_PENDING_IRQ, // confirmation IRQ seen (or synthesized) first; edpt0_xfer(STATUS OUT) fires xfer_complete }; typedef struct { @@ -436,11 +437,12 @@ static bool edpt0_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_ case PIPE0_STATE_STATUS_OUT: TU_ASSERT(!dir_in && total_bytes == 0); // only STATUS OUT allowed // First event of the STATUS OUT pair — wait for the IRQ to fire complete. - _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT_PENDING; + _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT_PENDING_XFER; break; - case PIPE0_STATE_STATUS_OUT_PENDING: - // Second event — IRQ already arrived, fire complete now. + case PIPE0_STATE_STATUS_OUT_PENDING_IRQ: + // Second event — IRQ already arrived, fire complete now. The old transfer is retired here, + // so a deferred SETUP can be replayed safely. _dcd.pipe0.state = PIPE0_STATE_IDLE; dcd_event_xfer_complete(rhport, ep_addr, 0, XFER_RESULT_SUCCESS, is_isr); pipe0_process_deferred_setup(rhport, ep_csr, is_isr); @@ -492,6 +494,7 @@ static void process_ep0(uint8_t rhport) { // so the whole packet drains in one shot. const uint16_t count0 = ep_csr->count0; if (count0) { + TU_ASSERT(_dcd.pipe0.buf, ); tu_hwfifo_read(&musb_regs->fifo[0], _dcd.pipe0.buf, count0, NULL); _dcd.pipe0.remain_wlength -= count0; } @@ -503,39 +506,48 @@ static void process_ep0(uint8_t rhport) { break; } - // New SETUP packet arrived while old control transfer is not finished yet. This could happen in following scenarios: - // - Status IN/OUT finished, IRQ and new setup packet IRQ arrive at the same time. - // - Data IN finished and status OUT is received, both IRQs and new setup packet IRQ arrive at the same time. - // could happen when CPU load is high, save the new setup packet for later processing after current status stage complete. + // New SETUP packet arrived while the old control transfer's tail events are still in flight + // (IRQs coalesced under high CPU load), e.g.: + // - Status IN/OUT finished, its IRQ and the new SETUP IRQ arrive at the same time. + // - Data IN finished and status OUT is received, both IRQs and the new SETUP IRQ arrive at the same time. + // Save the SETUP; it is replayed only once the old transfer is fully retired — i.e. when usbd has + // made (or already made) its final edpt0_xfer() call for it. case PIPE0_STATE_DATA_IN: case PIPE0_STATE_STATUS_OUT: - case PIPE0_STATE_STATUS_OUT_PENDING: + case PIPE0_STATE_STATUS_OUT_PENDING_XFER: + case PIPE0_STATE_STATUS_OUT_PENDING_IRQ: case PIPE0_STATE_STATUS_IN: { TU_VERIFY(pipe0_read_setup(musb_regs, ep_csr, &_dcd.pipe0.deferred_setup), ); _dcd.pipe0.deferred_setup_valid = true; switch (_dcd.pipe0.state) { case PIPE0_STATE_DATA_IN: - // Last DATA IN packet sent (TXRDY-clear coalesced with the SETUP IRQ). The STATUS OUT - // confirm IRQ is missed too — promote so edpt0_xfer(STATUS OUT) fires complete immediately. - if (_dcd.pipe0.remain_wlength == 0) { - _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT_PENDING; - } + // Coalesced: last DATA IN sent + status OUT done + new SETUP in one csrl read. Fire the + // DATA IN completion and synthesize the missed status confirm; usbd's edpt0_xfer(STATUS OUT) + // fires the status completion and replays. + TU_ASSERT(_dcd.pipe0.remain_wlength == 0, ); + _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT_PENDING_IRQ; dcd_event_xfer_complete(rhport, TU_EP0_IN, _dcd.pipe0.xact_len, XFER_RESULT_SUCCESS, true); break; case PIPE0_STATE_STATUS_OUT: // Status confirm IRQ coalesced with the SETUP — edpt0_xfer(STATUS OUT) fires complete. - _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT_PENDING; + _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT_PENDING_IRQ; break; - case PIPE0_STATE_STATUS_OUT_PENDING: - // edpt0_xfer(STATUS OUT) already called — fire complete and replay now. + case PIPE0_STATE_STATUS_OUT_PENDING_XFER: + // edpt0_xfer(STATUS OUT) already called — old transfer retired, complete and replay now. _dcd.pipe0.state = PIPE0_STATE_IDLE; dcd_event_xfer_complete(rhport, TU_EP0_OUT, 0, XFER_RESULT_SUCCESS, true); pipe0_process_deferred_setup(rhport, ep_csr, true); break; + case PIPE0_STATE_STATUS_OUT_PENDING_IRQ: + // usbd has not called edpt0_xfer(STATUS OUT) for the old transfer yet — only hold the + // SETUP. Replaying here would let that still-outstanding call land in the replayed + // transfer's state and corrupt it (e.g. NULL DATA OUT drain buffer). + break; + default: // PIPE0_STATE_STATUS_IN: ZLP-sent IRQ coalesced with the SETUP. if (_dcd.pipe0.pending_addr) { @@ -573,27 +585,26 @@ static void process_ep0(uint8_t rhport) { // to STATUS_OUT to await the host's STATUS-OUT ZLP confirmation IRQ. if (_dcd.pipe0.remain_wlength == 0) { _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT; - // If a new SETUP was deferred then STATUS OUT IRQ is missed, manually transition to STATUS_OUT_PENDING to allow ep0_xfer(STATUS OUT) to fire complete immediately. - if (_dcd.pipe0.deferred_setup_valid) { - _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT_PENDING; - } } dcd_event_xfer_complete(rhport, TU_EP0_IN, _dcd.pipe0.xact_len, XFER_RESULT_SUCCESS, true); - break; case PIPE0_STATE_STATUS_OUT: // First event of the STATUS OUT pair — wait for edpt0_xfer(STATUS OUT) to fire complete. - _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT_PENDING; + _dcd.pipe0.state = PIPE0_STATE_STATUS_OUT_PENDING_IRQ; break; - case PIPE0_STATE_STATUS_OUT_PENDING: + case PIPE0_STATE_STATUS_OUT_PENDING_XFER: // Second event — edpt0_xfer(STATUS OUT) already called, fire complete now. _dcd.pipe0.state = PIPE0_STATE_IDLE; dcd_event_xfer_complete(rhport, TU_EP0_OUT, 0, XFER_RESULT_SUCCESS, true); pipe0_process_deferred_setup(rhport, ep_csr, true); break; + case PIPE0_STATE_STATUS_OUT_PENDING_IRQ: + // Stale duplicate of the status confirm — already accounted for; edpt0_xfer fires complete. + break; + case PIPE0_STATE_STATUS_IN: if (_dcd.pipe0.pending_addr) { musb_regs->faddr = _dcd.pipe0.pending_addr; |