ehci: Add a ehci_writeback_async_complete_packet helper function

Also drop the warning printf, which was there mainly because this was an
untested code path (as the previous bug fixes to it show), but that no
longer is the case now :)

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Add ehci_verify_qh and ehci_verify_qtd helper functions

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Verify guest does not change the token of inflight qtd-s

This is not allowed, except for clearing active on cancellation, so don't
warn when the new token does not have its active bit set.

This unifies the cancellation path for modified qtd-s, and prepares
ehci_verify_qtd to be used ad an extra check inside
ehci_writeback_async_complete_packet().

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Move get / put_dwords upwards

No other changes.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: writeback_async_complete_packet: verify qh and qtd

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Verify qtd for async completed packets

Remove the short-circuiting of fetchqtd in fetchqh, so that the
qtd gets properly verified before completing the transaction.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Add an ehci_get_pid helper function

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Verify a queue's ep direction does not change

ehci_fill_queue assumes that there is a one on one relationship between an ep
and a qh, this patch adds a check to ensure this.

Note I don't expect this to ever trigger, this is just something I noticed
the guest might do while working on other stuff. The only way this check can
trigger is if a guest mixes in and out qtd-s in a single qh for a non
control ep.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Use uframe precision for interrupt threshold checking (v2)

Before this patch, the following could happen:
1) Transfer completes, raises interrupt
2) .5 ms later we check if the guest has queued up any new transfers
3) We find and execute a new transfer
4) .2 ms later the new transfer completes
5) We re-run our frame_timer to write back the completion, but less then
   1 ms has passed since our last run, so frindex is not changed, so the
   interrupt threshold code delays the interrupt
6) 1 ms from the re-run our frame-timer runs again and finally delivers
   the interrupt

This leads to unnecessary large delays of interrupts, this code fixes this
by changing frindex to uframe precision and using that for interrupt threshold
control, making the interrupt fire at step 5 for guest which have low interrupt
threshold settings (like Linux).

Note that the guest still sees the frindex move in steps of 8 for migration
compatibility.

This boosts Linux read speed of a simple cheap USB thumb drive by 6 %.

Changes in v2:
-Make the guest see frindex move in steps of 8 by modifying ehci_opreg_read,
 rather then using a shadow variable

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Further speedup rescanning if async schedule after raising an interrupt

I tried lowering the time between raising an interrupt and rescanning the
async schedule to see if the guest has queued a new transfer before, but
that did not have any positive effect. I now believe the cause for this is
that lowering this time made it more likely to hit the 1 ms interrupt
threshold penalty for the next packet, as described in my
"ehci: Use uframe precision for interrupt threshold checking" commit.

Now that we do interrupt threshold handling with uframe precision, futher
lowering this time from .5 to .25 ms gives an extra 15% improvement in speed
(MB/s) reading from a simple USB-2.0 thumb-drive.

While at it also properly set the int_req_by_async flag for short packet
completions.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Don't call commit_irq after raising PCD

ehci_raise_irq(s, USBSTS_PCD), gets applied immediately so there is no need
to call commit_irq after it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
uhci: Fix 1 ms delay in interrupt reporting to the guest

Re-arrange how we process frames / increase frnum / report pending interrupts,
to avoid a 1 ms delay in interrupt reporting to the guest. This increases
the packet throughput for cases where the guest submits a single packet,
then waits for its completion then re-submits from 500 pkts / sec to
1000 pkts / sec. This impacts for example the use of redirected / virtual
usb to serial convertors.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
uhci: Fix pending interrupts getting lost on migration

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
uhci: Add a QH_VALID define

Rather then using the magic 32 value in various places.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
uhci: Limit amount of frames processed in one go

Before this patch uhci would process an unlimited amount of frames when
behind on schedule, by setting the timer to a time already past, causing the
timer subsys to immediately recall the frame_timer function gain.

This would cause invalid cancellations of bulk queues when the catching up
processed more then 32 frames at a moment when the bulk qh was temporarily
unlinked (which the Linux uhci driver does).

This patch fixes this by processing maximum 16 frames in one go, and always
setting the timer one ms later, making the code behave more like the ehci
code.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
uhci: Maximize how many frames we catch up when behind

If somehow we've gotten behind a lot, simply skip ahead, like the ehci code
does.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
hid: Change idle handling to use a timer

This leads to cleaner code in usb-hid, and removes up to a 1000 calls / sec to
qemu_get_clock_ns(vm_clock) if idle-time is set to its default value of 0.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usb: Fix usb_ep_find_packet_by_id

usb_ep_find_packet_by_id mistakenly only checks the first packet and if that
is not a match, keeps trying the first packet! This patch fixes this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usb: Add an usb_device_ep_stopped USBDevice method

Some usb devices (host or network redirection) can benefit from knowing when
the guest stops using an endpoint. Redirection may involve submitting packets
independently from the guest (in combination with a fifo buffer between the
redirection code and the guest), to ensure that buffers of the real usb device
are timely emptied. This is done for example for isoc traffic and for interrupt
input endpoints. But when the (re)submission of packets is done by the device
code, then how does it know when to stop this?

For isoc endpoints this is handled by detecting a set interface (change alt
setting) command, which works well for isoc endpoints. But for interrupt
endpoints currently the redirection code never stops receiving data from
the device, which is less then ideal.

However the controller emulation is aware when a guest looses interest, as
then the qh for the endpoint gets unlinked (ehci, ohci, uhci) or the endpoint
is explicitly stopped (xhci). This patch adds a new ep_stopped USBDevice
method and modifies the hcd code to call this on queue unlink / ep stop.

This makes it possible for the redirection code to properly stop receiving
interrupt input (*) data when the guest no longer has interest in it.

*) And in the future also buffered bulk input.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usbredir: Add an usbredir_stop_ep helper function

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>