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authorGerd Hoffmann <kraxel@redhat.com>2012-05-11 09:18:05 +0200
committerGerd Hoffmann <kraxel@redhat.com>2012-06-07 10:02:20 +0200
commit4aed20e2d70f4353164399a173f20c3ab435b4eb (patch)
tree256092ca17acf13f36bfd4ef743a84844c9864b0 /hw/usb/hcd-uhci.c
parent349417004a0f7cf5518a998dca755cd06f6c212b (diff)
uhci: fix bandwidth management
uhci_process_frame() can be invoked multiple times per frame, so accounting usb bandwith in a local variable doesn't fly, use a variable in UHCIState instead. Also check the limit more frequently. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Diffstat (limited to 'hw/usb/hcd-uhci.c')
-rw-r--r--hw/usb/hcd-uhci.c22
1 files changed, 12 insertions, 10 deletions
diff --git a/hw/usb/hcd-uhci.c b/hw/usb/hcd-uhci.c
index 9e211a0bb4..48ad35c78d 100644
--- a/hw/usb/hcd-uhci.c
+++ b/hw/usb/hcd-uhci.c
@@ -131,6 +131,7 @@ struct UHCIState {
uint8_t status2; /* bit 0 and 1 are used to generate UHCI_STS_USBINT */
int64_t expire_time;
QEMUTimer *frame_timer;
+ uint32_t frame_bytes;
UHCIPort ports[NB_PORTS];
/* Interrupts that should be raised at the end of the current frame. */
@@ -985,7 +986,7 @@ static void uhci_fill_queue(UHCIState *s, UHCI_TD *td)
static void uhci_process_frame(UHCIState *s)
{
uint32_t frame_addr, link, old_td_ctrl, val, int_mask;
- uint32_t curr_qh, td_count = 0, bytes_count = 0;
+ uint32_t curr_qh, td_count = 0;
int cnt, ret;
UHCI_TD td;
UHCI_QH qh;
@@ -1002,6 +1003,12 @@ static void uhci_process_frame(UHCIState *s)
qhdb_reset(&qhdb);
for (cnt = FRAME_MAX_LOOPS; is_valid(link) && cnt; cnt--) {
+ if (s->frame_bytes >= 1280) {
+ /* We've reached the usb 1.1 bandwidth, which is
+ 1280 bytes/frame, stop processing */
+ trace_usb_uhci_frame_stop_bandwidth();
+ break;
+ }
if (is_qh(link)) {
/* QH */
trace_usb_uhci_qh_load(link & ~0xf);
@@ -1011,18 +1018,12 @@ static void uhci_process_frame(UHCIState *s)
* We're going in circles. Which is not a bug because
* 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.
+ * Stop processing here if no transaction has been done
+ * since we've been here last time.
*/
if (td_count == 0) {
trace_usb_uhci_frame_loop_stop_idle();
break;
- } else if (bytes_count >= 1280) {
- trace_usb_uhci_frame_loop_stop_bandwidth();
- break;
} else {
trace_usb_uhci_frame_loop_continue();
td_count = 0;
@@ -1085,7 +1086,7 @@ static void uhci_process_frame(UHCIState *s)
trace_usb_uhci_td_complete(curr_qh & ~0xf, link & ~0xf);
link = td.link;
td_count++;
- bytes_count += (td.ctrl & 0x7ff) + 1;
+ s->frame_bytes += (td.ctrl & 0x7ff) + 1;
if (curr_qh) {
/* update QH element link */
@@ -1118,6 +1119,7 @@ static void uhci_frame_timer(void *opaque)
/* prepare the timer for the next frame */
s->expire_time += (get_ticks_per_sec() / FRAME_TIMER_FREQ);
+ s->frame_bytes = 0;
if (!(s->cmd & UHCI_CMD_RS)) {
/* Full stop */