Searched hist:80826240 (Results 1 – 2 of 2) sorted by relevance
/openbmc/qemu/hw/usb/ |
H A D | hcd-ehci.h | 80826240 Sat Nov 17 05:47:17 CST 2012 Hans de Goede <hdegoede@redhat.com> ehci: Lower timer freq when the periodic schedule is idle Lower the timer freq if no iso schedule packets complete for 64 frames in a row. We can safely do this, without adding latency, because: 1) If there is isoc traffic this will never trigger 2) For async handled interrupt packets (only usb-host), the completion handler will immediately schedule the frame_timer from a bh 3) All devices using NAK to signal no data for interrupt endpoints now use wakeup, which will immediately schedule the frame_timer from a bh The advantage of this is that when we only have interrupt packets in the periodic schedule, async_stepdown can do its work and significantly lower the frequency at which the frame_timer runs. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
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H A D | hcd-ehci.c | 80826240 Sat Nov 17 05:47:17 CST 2012 Hans de Goede <hdegoede@redhat.com> ehci: Lower timer freq when the periodic schedule is idle Lower the timer freq if no iso schedule packets complete for 64 frames in a row. We can safely do this, without adding latency, because: 1) If there is isoc traffic this will never trigger 2) For async handled interrupt packets (only usb-host), the completion handler will immediately schedule the frame_timer from a bh 3) All devices using NAK to signal no data for interrupt endpoints now use wakeup, which will immediately schedule the frame_timer from a bh The advantage of this is that when we only have interrupt packets in the periodic schedule, async_stepdown can do its work and significantly lower the frequency at which the frame_timer runs. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
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