diff options
| -rw-r--r-- | hw/usb-uhci.c | 29 |
1 files changed, 22 insertions, 7 deletions
diff --git a/hw/usb-uhci.c b/hw/usb-uhci.c index cddcc8927..e0c7dbb71 100644 --- a/hw/usb-uhci.c +++ b/hw/usb-uhci.c @@ -73,7 +73,7 @@ #define FRAME_TIMER_FREQ 1000 -#define FRAME_MAX_LOOPS 100 +#define FRAME_MAX_LOOPS 256 #define NB_PORTS 2 @@ -942,7 +942,7 @@ static int qhdb_insert(QhDb *db, uint32_t addr) static void uhci_process_frame(UHCIState *s) { uint32_t frame_addr, link, old_td_ctrl, val, int_mask; - uint32_t curr_qh; + uint32_t curr_qh, td_count = 0, bytes_count = 0; int cnt, ret; UHCI_TD td; UHCI_QH qh; @@ -967,13 +967,26 @@ static void uhci_process_frame(UHCIState *s) if (qhdb_insert(&qhdb, link)) { /* * We're going in circles. Which is not a bug because - * HCD is allowed to do that as part of the BW management. - * In our case though it makes no sense to spin here. Sync transations - * are already done, and async completion handler will re-process - * the frame when something is ready. + * HCD is allowed to do that as part of the BW management. + * + * Stop processing here if + * (a) no transaction has been done since we've been + * here last time, or + * (b) we've reached the usb 1.1 bandwidth, which is + * 1280 bytes/frame. */ DPRINTF("uhci: detected loop. qh 0x%x\n", link); - break; + if (td_count == 0) { + DPRINTF("uhci: no transaction last round, stop\n"); + break; + } else if (bytes_count >= 1280) { + DPRINTF("uhci: bandwidth limit reached, stop\n"); + break; + } else { + td_count = 0; + qhdb_reset(&qhdb); + qhdb_insert(&qhdb, link); + } } pci_dma_read(&s->dev, link & ~0xf, &qh, sizeof(qh)); @@ -1033,6 +1046,8 @@ static void uhci_process_frame(UHCIState *s) link, td.link, td.ctrl, td.token, curr_qh); link = td.link; + td_count++; + bytes_count += (td.ctrl & 0x7ff) + 1; if (curr_qh) { /* update QH element link */ |