Fix an XHCI regression:

The Block Event Interrupts, BEI, feature does not
work like expected with the Renesas XHCI chipsets.
Revert feature.

While at it correct the TD SIZE computation in
case of Zero Length Packet, ZLP, in the end of a
multi frame USB transfer.

MFC after:	1 week
PR:		usb/180726

1 files changed, 9 insertions, 11 deletions

diff --git a/sys/dev/usb/controller/xhci.c b/sys/dev/usb/controller/xhci.c
index d25aa34..6c9a610 100644
--- a/sys/dev/usb/controller/xhci.c
+++ b/sys/dev/usb/controller/xhci.c
@@ -1682,7 +1682,6 @@ restart:
 			/* fill out buffer pointers */
 
 			if (average == 0) {
-				npkt = 0;
 				memset(&buf_res, 0, sizeof(buf_res));
 			} else {
 				usbd_get_page(temp->pc, temp->offset +
@@ -1697,14 +1696,16 @@ restart:
 					buf_res.length = XHCI_TD_PAGE_SIZE;
 
 				npkt_off += buf_res.length;
+			}
 
-				/* setup npkt */
-				npkt = (len_old - npkt_off + temp->max_packet_size - 1) /
-				    temp->max_packet_size;
+			/* setup npkt */
+			npkt = (len_old - npkt_off + temp->max_packet_size - 1) /
+			    temp->max_packet_size;
 
-				if (npkt > 31)
-					npkt = 31;
-			}
+			if (npkt == 0)
+				npkt = 1;
+			else if (npkt > 31)
+				npkt = 31;
 
 			/* fill out TRB's */
 			td->td_trb[x].qwTrb0 =
@@ -1719,9 +1720,7 @@ restart:
 
 			switch (temp->trb_type) {
 			case XHCI_TRB_TYPE_ISOCH:
-				/* BEI: Interrupts are inhibited until EOT */
 				dword = XHCI_TRB_3_CHAIN_BIT | XHCI_TRB_3_CYCLE_BIT |
-				    XHCI_TRB_3_BEI_BIT |
 				    XHCI_TRB_3_TBC_SET(temp->tbc) |
 				    XHCI_TRB_3_TLBPC_SET(temp->tlbpc);
 				if (td != td_first) {
@@ -1756,10 +1755,8 @@ restart:
 					dword |= XHCI_TRB_3_DIR_IN;
 				break;
 			default:	/* XHCI_TRB_TYPE_NORMAL */
-				/* BEI: Interrupts are inhibited until EOT */
 				dword = XHCI_TRB_3_CHAIN_BIT | XHCI_TRB_3_CYCLE_BIT |
 				    XHCI_TRB_3_TYPE_SET(XHCI_TRB_TYPE_NORMAL) |
-				    XHCI_TRB_3_BEI_BIT |
 				    XHCI_TRB_3_TBC_SET(temp->tbc) |
 				    XHCI_TRB_3_TLBPC_SET(temp->tlbpc);
 				if (temp->direction == UE_DIR_IN)
@@ -1838,6 +1835,7 @@ restart:
 		usb_pc_cpu_flush(td_first->page_cache);
 	}
 
+	/* clear TD SIZE to zero, hence this is the last TRB */
 	/* remove chain bit because this is the last TRB in the chain */
 	td->td_trb[td->ntrb - 1].dwTrb2 &= ~htole32(XHCI_TRB_2_TDSZ_SET(15));
 	td->td_trb[td->ntrb - 1].dwTrb3 &= ~htole32(XHCI_TRB_3_CHAIN_BIT);