[efi] Do not attempt EFI_USB_IO_PROTOCOL transfers during shutdown
On at least some platforms (observed with a Raspberry Pi), any attempt
to perform USB transfers via EFI_USB_IO_PROTOCOL during EFI shutdown
will lock up the system. This is quite probably due to the already
documented failure of all EFI timers when ExitBootServices() is
called: see e.g. commit 5cf5ffea2 "[efi] Work around temporal anomaly
encountered during ExitBootServices()".
Work around this problem by refusing to poll endpoints if shutdown is
in progress, and by immediately failing any attempts to enqueue new
transfers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Report failed control transfers as expected by the USB core
The USB core reuses the I/O buffer space occupied by the USB setup
packet to hold the completion status for message transfers, assuming
that the message() method will always strip the setup packet before
returning. This assumption is correct for all of the hardware
controller drivers (XHCI, EHCI, and UHCI), since these drivers are
able to enqueue the transfer as a separate action from waiting for the
transfer to complete.
The EFI_USB_IO_PROTOCOL does not allow us to separate actions in this
way: there is only a single blocking method that both enqueues and
waits for completion. Our usbio driver therefore currently defers
stripping the setup packet until the control endpoint is polled.
This causes a bug if a message transfer is enqueued but never polled
and is subsequently cancelled, since the cancellation will be reported
with the I/O buffer still containing the setup packet. This breaks
the assumption that the setup packet has been stripped, and triggers
an assertion failure in usb_control_complete().
Fix by always stripping the setup packet in usbio_endpoint_message(),
and adjusting usbio_control_poll() to match.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Make the class ID a property of the USB driver (rather than a property
of the USB device ID), and allow USB drivers to specify a wildcard ID
for any of the three component IDs (class, subclass, or protocol).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[usb] Select preferred USB device configuration based on driver score
Generate a score for each possible USB device configuration based on
the available driver support, and select the configuration with the
highest score. This will allow us to prefer ECM over RNDIS (for
devices which support both) and will allow us to meaningfully select a
configuration even when we have drivers available for all functions
(e.g. when exposing unused functions via EFI_USB_IO_PROTOCOL).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The decision on whether or not a zero-length packet needs to be
transmitted is independent of the host controller and belongs in the
USB core.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Add a USB host controller driver based on EFI_USB_IO_PROTOCOL
Allow iPXE to coexist with other USB device drivers, by attaching to
the EFI_USB_IO_PROTOCOL instances provided by the UEFI platform
firmware.
The EFI_USB_IO_PROTOCOL is an unsurprisingly badly designed
abstraction of a USB device. The poor design choices intrinsic in the
UEFI specification prevent efficient operation as a network device,
with the result that devices operated using the EFI_USB_IO_PROTOCOL
operate approximately two orders of magnitude slower than devices
operated using our native EHCI or xHCI host controller drivers.
Since the performance is so abysmally slow, and since the underlying
problems are due to fundamental architectural mistakes in the UEFI
specification, support for the EFI_USB_IO_PROTOCOL host controller
driver is left as disabled by default. Users are advised to use the
native iPXE host controller drivers instead.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown