[PATCH v2 00/11] hw/usb/aspeed-udc: Add AST1030 UDC support

[Jamin Lin <jamin_lin@aspeedtech.com>]

This series adds USB Device Controller (UDC) support for the ASPEED
AST1030 and extends the existing ASPEED UDC model with the transfer
handling required by the AST1030.

The v1 series included both the usbredir server transport and the ASPEED
AST1030 UDC support. Following review feedback, the two parts have been
split into separate series. The usbredir server transport is now sent
separately, while this series contains the ASPEED AST1030 UDC changes.

Dependency
==========

The AST1030 UDC implementation itself does not depend on the usbredir
server transport series. However, the functional test in this series
does depend on it, because the AST1030 has no USB host controller and
requires usb-redir-server to export the emulated USB gadget to a USB
host controller in another QEMU instance.

The functional test therefore depends on:

[PATCH v2 0/8] hw/usb: Add a usbredir server transport
https://patchwork.kernel.org/project/qemu-devel/cover/20261005032022.3980903-1-jamin_lin@aspeedtech.com/

Background
==========

This work is part of a larger plan to model USB device-side support on
ASPEED BMC/BIC SoCs, which has three goals:

1. Model the ASPEED UDC (AST2600 / AST1030). The AST2600 also has USB host
   (EHCI) controllers, so that work targets the AST2600 UDC: its gadget can
   be attached to the SoC's own EHCI bus, letting the guest enumerate its
   own gadget and exercise the UDC end-to-end.  [Done]
   https://lore.kernel.org/qemu-devel/20260902021542.3194812-1-jamin_lin@aspeedtech.com/

2. AST1030 UDC. The AST1030 has no USB host controller, so testing its UDC
   needs a second QEMU instance. The UDC gadget is redirected out of the
   guest with libusbredir and attached to another QEMU that runs a USB host
   (a VMM, or an AST2600 / AST2700 guest).  [this series]

3. ASPEED vHub, as a longer-term goal towards BMC KVM / Virtual Media
   support in QEMU.  [future]

This series implements goal 2.

AST1030 gadget to an AST2700 host
=================================

        QEMU #1  -M ast1030-evb              QEMU #2  -M ast2700a2-evb
  +-----------------------------+      +-----------------------------+
  | Zephyr   usb_dc_aspeed      |      | Linux    ehci-platform      |
  +--------------+--------------+      +--------------+--------------+
                 | MMIO                               | MMIO
  +--------------v--------------+      +--------------v--------------+
  | aspeed.udc                  |      | EHCI3        (usb-bus.3)    |
  +--------------+--------------+      +--------------+--------------+
                 | USBPacket                          | USBPacket
  +--------------v--------------+      +--------------v--------------+
  | aspeed.udc-gadget           |      | usb-redir                   |
  +--------------+--------------+      +--------------+--------------+
                 | USBPacket                          |
  +--------------v--------------+                     |
  | usb-redir-server            |                     |
  +--------------+--------------+                     |
                 |                                    |
                 +=========== unix socket ============+
                           usbredir protocol

Testing
=======

The AST1030 UDC was tested with a Zephyr CDC-ACM gadget. The AST1030
side exports the gadget through usb-redir-server:

$ qemu-system-arm -M ast1030-evb -nographic
-kernel zephyr.bin
-chardev socket,id=u,path=/tmp/usbredir.sock,server=on,wait=off
-device usb-redir-server,id=udcredir,chardev=u
-device aspeed.udc-gadget,bus=udcredir.0,udc=/machine/soc/udc

uart:~$ usb enable
uart:~$ usb print 1

The gadget is attached to EHCI3 of an AST2700 guest through the
usb-redir client:

$ qemu-system-aarch64 -M ast2700a2-evb -nographic
-drive file=image-bmc,if=mtd,format=raw -snapshot
-net nic -net user
-chardev socket,id=r,path=/tmp/usbredir.sock
-device usb-redir,chardev=r,bus=usb-bus.3

The AST2700 guest enumerates the AST1030 gadget:

root@ast2700-default:~# lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux 6.18.36 ehci_hcd EHCI Host Controller
Bus 001 Device 002: ID 2245:1030 ZEPHYR Zephyr DFU sample

Data transfer was also checked:

2700 -> 1030 
echo '1234567890' > /dev/ttyACM0
1030 console: Print Data: 0x31 0x32 ... 0x30

A functional test is added to exercise the AST1030 UDC through this
usbredir setup.

v1:
  1. Make the SETUP buffer byte addressable
  2. Support single-stage IN transfers
  3. Clear EP_POOL_ACK when no endpoint ack is left
  4. Mask the reserved bits on register writes
  5. Use the endpoint max packet size for OUT transfers
  6. Test the usbredir server transport
  7. Add the USB device controller for AST1030
  
v2:
  1. Split the usbredir server transport into a separate series as
     suggested during review.
  2. Keep this series focused on the ASPEED UDC changes and AST1030
     UDC support.
  3. Add the AST1030 functional test using the usbredir server transport.

Jamin Lin (11):
  hw/usb/aspeed-udc: Make the SETUP buffer byte addressable
  hw/usb/aspeed-udc: Mask the reserved bits on register writes
  hw/usb/aspeed-udc: Clear EP_POOL_ACK when no endpoint ack is left
  hw/usb/aspeed-udc: Rename the transfer helpers after their DMA mode
  hw/usb/aspeed-udc: Store the EP_DMA_STS write first
  hw/usb/aspeed-udc: Pick the EP_DMA_STS path by direction
  hw/usb/aspeed-udc: Support single-stage IN transfers
  hw/usb/aspeed-udc: Use the endpoint max packet size for OUT transfers
  hw/usb/aspeed-udc: Add trace events for the transfer paths
  hw/arm/aspeed_ast10x0: Add the USB device controller
  tests/functional/arm/test_aspeed_ast1030: Test the usbredir server
    transport

 include/hw/arm/aspeed_soc.h                 |   1 +
 include/hw/usb/aspeed-udc.h                 |  13 +-
 hw/arm/aspeed_ast10x0.c                     |  17 +-
 hw/usb/aspeed-udc.c                         | 290 ++++++++++++++++----
 hw/usb/trace-events                         |   9 +
 tests/functional/arm/meson.build            |   1 +
 tests/functional/arm/test_aspeed_ast1030.py |  52 ++++
 7 files changed, 330 insertions(+), 53 deletions(-)

-- 
2.43.0