From: mpi <mpi@openbsd.org>
Date: Sun, 18 Jan 2015 14:49:04 +0000 (+0000)
Subject: Complete synchronous abort method modeled after the existing ones.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=1be52566c468e0195c6fbfc1f2c8652fea7cb0f2;p=openbsd

Complete synchronous abort method modeled after the existing ones.

Because our USB stack wants the aborted xfer to be removed from the
pipe during abort(), we have to sleep in the abort function.

Regarding the xHCI process, when a TD is being aborted, we simply stop
the endpoint and then move the dequeue pointer past its last TRB.  This
is fairly simple for the moment since only one xfer can be pending on a
given pipe.
---

diff --git a/sys/dev/usb/xhci.c b/sys/dev/usb/xhci.c
index 6ad74c60afa..ab50aa94c4b 100644
--- a/sys/dev/usb/xhci.c
+++ b/sys/dev/usb/xhci.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: xhci.c,v 1.55 2015/01/18 11:54:02 mpi Exp $ */
+/* $OpenBSD: xhci.c,v 1.56 2015/01/18 14:49:04 mpi Exp $ */
 
 /*
  * Copyright (c) 2014-2015 Martin Pieuchot
@@ -49,7 +49,7 @@ int xhcidebug = 3;
 #define DPRINTFN(n,x)
 #endif
 
-#define DEVNAME(sc)		((sc)->sc_bus.bdev.dv_xname)
+#define DEVNAME(sc)	((sc)->sc_bus.bdev.dv_xname)
 
 #define TRBOFF(r, trb)	((char *)(trb) - (char *)((r)->trbs))
 #define DEQPTR(r)	((r).dma.paddr + (sizeof(struct xhci_trb) * (r).index))
@@ -117,6 +117,7 @@ void	xhci_pipe_close(struct usbd_pipe *);
 void	xhci_noop(struct usbd_xfer *);
 
 void 	xhci_timeout(void *);
+void	xhci_timeout_task(void *);
 
 /* USBD Bus Interface. */
 usbd_status	  xhci_pipe_open(struct usbd_pipe *);
@@ -777,6 +778,7 @@ xhci_event_xfer(struct xhci_softc *sc, uint64_t paddr, uint32_t status,
 	case XHCI_CODE_BABBLE:
 		/* Prevent any timeout to kick in. */
 		timeout_del(&xfer->timeout_handle);
+		usb_rem_task(xfer->device, &xfer->abort_task);
 
 		/* We need to report this condition for umass(4). */
 		if (code == XHCI_CODE_STALL)
@@ -792,6 +794,15 @@ xhci_event_xfer(struct xhci_softc *sc, uint64_t paddr, uint32_t status,
 		xp->aborted_xfer = xfer;
 		xhci_cmd_reset_ep_async(sc, slot, dci);
 		return;
+	case XHCI_CODE_XFER_STOPPED:
+	case XHCI_CODE_XFER_STOPINV:
+		/* Endpoint stopped while processing a TD. */
+		if (xfer == xp->aborted_xfer) {
+			DPRINTF(("%s: stopped xfer=%p\n", __func__, xfer));
+		    	return;
+		}
+
+		/* FALLTHROUGH */
 	default:
 		DPRINTF(("%s: unhandled code %d\n", DEVNAME(sc), code));
 		xfer->status = USBD_IOERROR;
@@ -841,9 +852,9 @@ xhci_event_command(struct xhci_softc *sc, uint64_t paddr)
 			break;
 
 		xp->halted = 0;
-
 		if (xp->aborted_xfer != NULL) {
 			xhci_xfer_done(xp->aborted_xfer);
+			wakeup(xp);
 		}
 		break;
 	default:
@@ -911,6 +922,7 @@ xhci_xfer_done(struct usbd_xfer *xfer)
 	xx->ntrb = 0;
 
 	timeout_del(&xfer->timeout_handle);
+	usb_rem_task(xfer->device, &xfer->abort_task);
 	usb_transfer_complete(xfer);
 }
 
@@ -1257,8 +1269,6 @@ xhci_pipe_close(struct usbd_pipe *pipe)
 	/* Root Hub */
 	if (pipe->device->depth == 0)
 		return;
-	if (!xp->halted || xhci_cmd_stop_ep(sc, xp->slot, xp->dci))
-		DPRINTF(("%s: error stopping ep (%d)\n", DEVNAME(sc), xp->dci));
 
 	/* Mask the endpoint */
 	sdev->input_ctx->drop_flags = htole32(XHCI_INCTX_MASK_DCI(xp->dci));
@@ -1883,18 +1893,85 @@ const usb_hub_descriptor_t xhci_hubd = {
 void
 xhci_abort_xfer(struct usbd_xfer *xfer, usbd_status status)
 {
+	struct xhci_softc *sc = (struct xhci_softc *)xfer->device->bus;
+	struct xhci_pipe *xp = (struct xhci_pipe *)xfer->pipe;
+	int error;
+
 	splsoftassert(IPL_SOFTUSB);
 
 	DPRINTF(("%s: xfer=%p status=%s err=%s actlen=%d len=%d idx=%d\n",
 	    __func__, xfer, usbd_errstr(xfer->status), usbd_errstr(status),
 	    xfer->actlen, xfer->length, ((struct xhci_xfer *)xfer)->index));
 
+	/* XXX The stack should not call abort() in this case. */
+	if (xfer->status == USBD_NOT_STARTED) {
+		xfer->status = status;
+		usb_transfer_complete(xfer);
+		return;
+	}
+
+	/* Transfer is already done. */
+	if (xfer->status != USBD_IN_PROGRESS) {
+		DPRINTF(("%s: already done \n", __func__));
+		return;
+	}
+
+	/* Prevent any timeout to kick in. */
+	timeout_del(&xfer->timeout_handle);
+	usb_rem_task(xfer->device, &xfer->abort_task);
+
+	/* Indicate that we are aborting this transfer. */
 	xfer->status = status;
-	xhci_xfer_done(xfer);
+	xp->halted = 1;
+	xp->aborted_xfer = xfer;
+
+	/* Stop the endpoint and wait until the hardware says so. */
+	if (xhci_cmd_stop_ep(sc, xp->slot, xp->dci))
+		DPRINTF(("%s: error stopping endpoint\n", DEVNAME(sc)));
+
+	/*
+	 * The transfer was already completed when we stopped the
+	 * endpoint, no need to move the dequeue pointer past its
+	 * TRBs.
+	 */
+	if (xp->aborted_xfer == NULL) {
+		DPRINTF(("%s: done before stopping the endpoint\n", __func__));
+		xp->halted = 0;
+		return;
+	}
+
+	/*
+	 * At this stage the endpoint has been stopped, so update its
+	 * dequeue pointer past the last TRB of the transfer.
+	 *
+	 * Note: This assume that only one transfer per endpoint has
+	 *	 pending TRBs on the ring.
+	 */
+	xhci_cmd_set_tr_deq_async(sc, xp->slot, xp->dci,
+	    DEQPTR(xp->ring) | xp->ring.toggle);
+	error = tsleep(xp, PZERO, "xhciab", (XHCI_COMMAND_TIMEOUT*hz+999)/1000 + 1);
+	if (error)
+		printf("%s: timeout aborting transfer\n", DEVNAME(sc));
 }
 
 void
 xhci_timeout(void *addr)
+{
+	struct usbd_xfer *xfer = addr;
+	struct xhci_softc *sc = (struct xhci_softc *)xfer->device->bus;
+
+	if (sc->sc_bus.dying) {
+		xhci_timeout_task(addr);
+		return;
+	}
+
+	usb_init_task(&xfer->abort_task, xhci_timeout_task, addr,
+	    USB_TASK_TYPE_ABORT);
+	usb_add_task(xfer->device, &xfer->abort_task);
+}
+
+void
+xhci_timeout_task(void *addr)
 {
 	struct usbd_xfer *xfer = addr;
 	int s;
diff --git a/sys/dev/usb/xhcireg.h b/sys/dev/usb/xhcireg.h
index 74e5edad8bb..424b8cb881d 100644
--- a/sys/dev/usb/xhcireg.h
+++ b/sys/dev/usb/xhcireg.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: xhcireg.h,v 1.9 2015/01/02 18:06:25 mpi Exp $ */
+/* $OpenBSD: xhcireg.h,v 1.10 2015/01/18 14:49:04 mpi Exp $ */
 
 /*-
  * Copyright (c) 2014 Martin Pieuchot. All rights reserved.
@@ -435,7 +435,7 @@ struct xhci_trb {
 #define XHCI_CODE_CMD_RING_STOP	24 	/* Command Stop (CS) requested */
 #define XHCI_CODE_CMD_ABORTED	25 	/* Command Abort (CA) operation */
 #define XHCI_CODE_XFER_STOPPED	26 	/* xfer terminated by a stop endpoint */
-#define XHCI_CODE_XFER_INVLEN	27 	/* TRB transfer length invalid */
+#define XHCI_CODE_XFER_STOPINV	27 	/* TRB transfer length invalid */
 #define XHCI_CODE_XFER_SHORTPKT	28 	/* Stopped before reaching end of TD */
 #define XHCI_CODE_MELAT		29	/* Max Exit Latency too large */
 #define XHCI_CODE_RESERVED	30