[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] CAN device
From: |
Andreas Färber |
Subject: |
Re: [Qemu-devel] CAN device |
Date: |
Fri, 28 Jun 2013 14:51:25 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130510 Thunderbird/17.0.6 |
Hi,
Am 28.06.2013 14:19, schrieb Yang Jin:
> I try to develop a CAN device on QEMU. And I found pci-serial is similar
> to CAN.
>
> Untill now, I have some questions about how to use pci-serial on QEMU.
> Actually, QEMU use isa-serial as a default serial device. So I try to
> use isa-serial firstly.
>
> Some useful information we can get from docs/qdev-device-use.txt. I know
> that we should use "-chardev" argument to create a host part, and then
> use "-device isa-serial,iobase=IOADDR,irq=IRQ,index=IDX" to start a
> isa-serial. I get those arguments from the source file, the following
> can work.
> "-device isa-serial,chardev=isa0,iobase=0x3f8,irq=4,index=0"
> However, when I try to create a host through "-chardev
> serial,id=isa0,path=./", error "chardev: opening backend "serial"
> failed" occurs. When change it to "-chardev
> serial,id=isa0,path=/dev/ttyS0", it works. Now, I donot know what "path"
> means? Does it have some relation to the host device? Or it's just a
> symbol means nothing.
Searching man qemu for "chardev serial" should answer that question. :)
There you will also find alternative chardev backends you can use.
> And some questions about pci bus. On docs/qdev-device-use.txt, we get
> Example: device i440FX-pcihost is on the root bus, and provides a PCI
> bus named pci.0. To put a FOO device into its slot 4, use -device
> FOO,bus=/i440FX-pcihost/pci.0,addr=4. The abbreviated form bus=pci.0
> also works as long as the bus name is unique.
> So, how can we get the name of the root device which we use now?
You can browse the QOM hierarchy using the ./QMP/qom-list script and an
appropriate -qmp option (e.g. unix:./qmp-sock,server,nowait).
But leaving out the bus= option should work fine just as well.
Regards,
Andreas
> I searched that for some days, but doesnot get some usefull information.
>
> Thanks,
> Jin yang.
--
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg