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author | Christoph Hellwig <hch@lst.de> | 2023-01-10 12:10:08 +0300 |
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committer | Alex Williamson <alex.williamson@redhat.com> | 2023-01-23 21:26:29 +0300 |
commit | 0030d7d6ce319c32551395ebc00c533f50a0b0fe (patch) | |
tree | dfad9fd1461ec2853f133bc5292b557fa2a1e944 /Documentation/driver-api/vfio-mediated-device.rst | |
parent | 8bf8c5ee1f3863d944c1d8c29335f0c790b4f851 (diff) | |
download | linux-0030d7d6ce319c32551395ebc00c533f50a0b0fe.tar.xz |
vfio-mdev: move the mtty usage documentation
Move the documentation on how to use mtty to samples/vfio-mdev/README.rst
as it is in no way related to the vfio API. This matches how the bpf
and pktgen samples are documented.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230110091009.474427-4-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Diffstat (limited to 'Documentation/driver-api/vfio-mediated-device.rst')
-rw-r--r-- | Documentation/driver-api/vfio-mediated-device.rst | 100 |
1 files changed, 0 insertions, 100 deletions
diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst index fdf7d69378ec..d4267243b4f5 100644 --- a/Documentation/driver-api/vfio-mediated-device.rst +++ b/Documentation/driver-api/vfio-mediated-device.rst @@ -270,106 +270,6 @@ these callbacks are supported in the TYPE1 IOMMU module. To enable them for other IOMMU backend modules, such as PPC64 sPAPR module, they need to provide these two callback functions. -Using the Sample Code -===================== - -mtty.c in samples/vfio-mdev/ directory is a sample driver program to -demonstrate how to use the mediated device framework. - -The sample driver creates an mdev device that simulates a serial port over a PCI -card. - -1. Build and load the mtty.ko module. - - This step creates a dummy device, /sys/devices/virtual/mtty/mtty/ - - Files in this device directory in sysfs are similar to the following:: - - # tree /sys/devices/virtual/mtty/mtty/ - /sys/devices/virtual/mtty/mtty/ - |-- mdev_supported_types - | |-- mtty-1 - | | |-- available_instances - | | |-- create - | | |-- device_api - | | |-- devices - | | `-- name - | `-- mtty-2 - | |-- available_instances - | |-- create - | |-- device_api - | |-- devices - | `-- name - |-- mtty_dev - | `-- sample_mtty_dev - |-- power - | |-- autosuspend_delay_ms - | |-- control - | |-- runtime_active_time - | |-- runtime_status - | `-- runtime_suspended_time - |-- subsystem -> ../../../../class/mtty - `-- uevent - -2. Create a mediated device by using the dummy device that you created in the - previous step:: - - # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" > \ - /sys/devices/virtual/mtty/mtty/mdev_supported_types/mtty-2/create - -3. Add parameters to qemu-kvm:: - - -device vfio-pci,\ - sysfsdev=/sys/bus/mdev/devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001 - -4. Boot the VM. - - In the Linux guest VM, with no hardware on the host, the device appears - as follows:: - - # lspci -s 00:05.0 -xxvv - 00:05.0 Serial controller: Device 4348:3253 (rev 10) (prog-if 02 [16550]) - Subsystem: Device 4348:3253 - Physical Slot: 5 - Control: I/O+ Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- - Stepping- SERR- FastB2B- DisINTx- - Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- - <TAbort- <MAbort- >SERR- <PERR- INTx- - Interrupt: pin A routed to IRQ 10 - Region 0: I/O ports at c150 [size=8] - Region 1: I/O ports at c158 [size=8] - Kernel driver in use: serial - 00: 48 43 53 32 01 00 00 02 10 02 00 07 00 00 00 00 - 10: 51 c1 00 00 59 c1 00 00 00 00 00 00 00 00 00 00 - 20: 00 00 00 00 00 00 00 00 00 00 00 00 48 43 53 32 - 30: 00 00 00 00 00 00 00 00 00 00 00 00 0a 01 00 00 - - In the Linux guest VM, dmesg output for the device is as follows: - - serial 0000:00:05.0: PCI INT A -> Link[LNKA] -> GSI 10 (level, high) -> IRQ 10 - 0000:00:05.0: ttyS1 at I/O 0xc150 (irq = 10) is a 16550A - 0000:00:05.0: ttyS2 at I/O 0xc158 (irq = 10) is a 16550A - - -5. In the Linux guest VM, check the serial ports:: - - # setserial -g /dev/ttyS* - /dev/ttyS0, UART: 16550A, Port: 0x03f8, IRQ: 4 - /dev/ttyS1, UART: 16550A, Port: 0xc150, IRQ: 10 - /dev/ttyS2, UART: 16550A, Port: 0xc158, IRQ: 10 - -6. Using minicom or any terminal emulation program, open port /dev/ttyS1 or - /dev/ttyS2 with hardware flow control disabled. - -7. Type data on the minicom terminal or send data to the terminal emulation - program and read the data. - - Data is loop backed from hosts mtty driver. - -8. Destroy the mediated device that you created:: - - # echo 1 > /sys/bus/mdev/devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001/remove - References ========== |