Commit 3ee71c57 authored by Tom Rini's avatar Tom Rini
Browse files

Merge https://source.denx.de/u-boot/custodians/u-boot-x86

- x86: correct regwidth prompt in cbsysinfo
- virtio: convert README.virtio to reST
parents 07b53103 200fdd3b
......@@ -1171,6 +1171,18 @@ F: common/lcd*.c
F: include/lcd*.h
F: include/video*.h
VirtIO
M: Bin Meng <bmeng.cn@gmail.com>
S: Maintained
F: drivers/virtio/
F: cmd/virtio.c
F: include/config/virtio/
F: include/config/virtio.h
F: include/config/cmd/virtio.h
F: include/virtio*.h
F: test/dm/virtio.c
F: doc/develop/driver-model/virtio.rst
X86
M: Simon Glass <sjg@chromium.org>
M: Bin Meng <bmeng.cn@gmail.com>
......
......@@ -205,7 +205,7 @@ static void show_table(struct sysinfo_t *info, bool verbose)
print_hex(">type", ser->type);
print_addr(">base", ser->baseaddr);
print_dec(">baud", ser->baud);
print_hex(">baud", ser->regwidth);
print_hex(">regwidth", ser->regwidth);
print_dec(">input_hz", ser->input_hertz);
print_addr(">PCI addr", ser->uart_pci_addr);
}
......
......@@ -27,3 +27,4 @@ subsystems
soc-framework
spi-howto
usb-info
virtio
# SPDX-License-Identifier: GPL-2.0+
#
# Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
.. SPDX-License-Identifier: GPL-2.0+
.. sectionauthor:: Bin Meng <bmeng.cn@gmail.com>
VirtIO Support
==============
This document describes the information about U-Boot support for VirtIO [1]
This document describes the information about U-Boot support for VirtIO_
devices, including supported boards, build instructions, driver details etc.
What's VirtIO?
......@@ -15,7 +14,7 @@ just the guest's device driver "knows" it is running in a virtual environment,
and cooperates with the hypervisor. This enables guests to get high performance
network and disk operations, and gives most of the performance benefits of
paravirtualization. In the U-Boot case, the guest is U-Boot itself, while the
virtual environment are normally QEMU [2] targets like ARM, RISC-V and x86.
virtual environment are normally QEMU_ targets like ARM, RISC-V and x86.
Status
------
......@@ -49,6 +48,8 @@ Building U-Boot for pre-configured QEMU targets is no different from others.
For example, we can do the following with the CROSS_COMPILE environment
variable being properly set to a working toolchain for ARM:
.. code-block:: bash
$ make qemu_arm_defconfig
$ make
......@@ -56,11 +57,13 @@ You can even create a QEMU ARM target with VirtIO devices showing up on both
MMIO and PCI buses. In this case, you can enable the PCI transport driver
from 'make menuconfig':
Device Drivers --->
...
VirtIO Drivers --->
...
[*] PCI driver for virtio devices
.. code-block:: none
Device Drivers --->
...
VirtIO Drivers --->
...
[*] PCI driver for virtio devices
Other drivers are at the same location and can be tuned to suit the needs.
......@@ -74,6 +77,8 @@ Testing
The following QEMU command line is used to get U-Boot up and running with
VirtIO net and block devices on ARM.
.. code-block:: bash
$ qemu-system-arm -nographic -machine virt -bios u-boot.bin \
-netdev tap,ifname=tap0,id=net0 \
-device virtio-net-device,netdev=net0 \
......@@ -82,6 +87,8 @@ VirtIO net and block devices on ARM.
On x86, command is slightly different to create PCI VirtIO devices.
.. code-block:: bash
$ qemu-system-i386 -nographic -bios u-boot.rom \
-netdev tap,ifname=tap0,id=net0 \
-device virtio-net-pci,netdev=net0 \
......@@ -93,6 +100,8 @@ parameters. It is also possible to specify both MMIO and PCI VirtIO devices.
For example, the following commnad creates 3 VirtIO devices, with 1 on MMIO
and 2 on PCI bus.
.. code-block:: bash
$ qemu-system-arm -nographic -machine virt -bios u-boot.bin \
-netdev tap,ifname=tap0,id=net0 \
-device virtio-net-pci,netdev=net0 \
......@@ -104,6 +113,8 @@ and 2 on PCI bus.
By default QEMU creates VirtIO legacy devices by default. To create non-legacy
(aka modern) devices, pass additional device property/value pairs like below:
.. code-block:: bash
$ qemu-system-i386 -nographic -bios u-boot.rom \
-netdev tap,ifname=tap0,id=net0 \
-device virtio-net-pci,netdev=net0,disable-legacy=true,disable-modern=false \
......@@ -112,6 +123,8 @@ By default QEMU creates VirtIO legacy devices by default. To create non-legacy
A 'virtio' command is provided in U-Boot shell.
.. code-block:: none
=> virtio
virtio - virtio block devices sub-system
......@@ -127,10 +140,14 @@ A 'virtio' command is provided in U-Boot shell.
To probe all the VirtIO devices, type:
.. code-block:: none
=> virtio scan
Then we can show the connected block device details by:
.. code-block:: none
=> virtio info
Device 0: QEMU VirtIO Block Device
Type: Hard Disk
......@@ -138,6 +155,8 @@ Then we can show the connected block device details by:
And list the directories and files on the disk by:
.. code-block:: none
=> ls virtio 0 /
<DIR> 4096 .
<DIR> 4096 ..
......@@ -167,6 +186,8 @@ Driver Internals
----------------
There are 3 level of drivers in the VirtIO driver family.
.. code-block:: none
+---------------------------------------+
| virtio device drivers |
| +-------------+ +------------+ |
......@@ -199,20 +220,26 @@ The transport drivers provide a set of ops (struct dm_virtio_ops) for the real
virtio device driver to call. These ops APIs's parameter is designed to remind
the caller to pass the correct 'struct udevice' id of the virtio device, eg:
int virtio_get_status(struct udevice *vdev, u8 *status)
.. code-block:: C
int virtio_get_status(struct udevice *vdev, u8 *status)
So the parameter 'vdev' indicates the device should be the real virtio device.
But we also have an API like:
struct virtqueue *vring_create_virtqueue(unsigned int index, unsigned int num,
unsigned int vring_align,
struct udevice *udev)
.. code-block:: C
struct virtqueue *vring_create_virtqueue(unsigned int index, unsigned int num,
unsigned int vring_align,
struct udevice *udev)
Here the parameter 'udev' indicates the device should be the transport device.
Similar naming is applied in other functions that are even not APIs, eg:
static int virtio_uclass_post_probe(struct udevice *udev)
static int virtio_uclass_child_pre_probe(struct udevice *vdev)
.. code-block:: C
static int virtio_uclass_post_probe(struct udevice *udev)
static int virtio_uclass_child_pre_probe(struct udevice *vdev)
So it's easy to tell which device these functions are operating on.
......@@ -223,20 +250,29 @@ ID 2) are supported. If you want to develop new driver for new devices,
please follow the guideline below.
1. add new device ID in virtio.h
#define VIRTIO_ID_XXX X
.. code-block:: C
#define VIRTIO_ID_XXX X
2. update VIRTIO_ID_MAX_NUM to be the largest device ID plus 1
3. add new driver name string in virtio.h
#define VIRTIO_XXX_DRV_NAME "virtio-xxx"
.. code-block:: C
#define VIRTIO_XXX_DRV_NAME "virtio-xxx"
4. create a new driver with name set to the name string above
U_BOOT_DRIVER(virtio_xxx) = {
.name = VIRTIO_XXX_DRV_NAME,
...
.remove = virtio_reset,
.flags = DM_FLAG_ACTIVE_DMA,
}
.. code-block:: C
U_BOOT_DRIVER(virtio_xxx) = {
.name = VIRTIO_XXX_DRV_NAME,
...
.remove = virtio_reset,
.flags = DM_FLAG_ACTIVE_DMA,
}
Note the driver needs to provide the remove method and normally this can be
hooked to virtio_reset(). The driver flags should contain DM_FLAG_ACTIVE_DMA
......@@ -247,7 +283,5 @@ for the remove method to be called before jumping to OS.
6. do funny stuff with the driver
References
----------
[1] http://docs.oasis-open.org/virtio/virtio/v1.0/virtio-v1.0.pdf
[2] https://www.qemu.org
.. _VirtIO: http://docs.oasis-open.org/virtio/virtio/v1.0/virtio-v1.0.pdf
.. _QEMU: https://www.qemu.org
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