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.
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?
I searched that for some days, but doesnot get some usefull information.
Thanks,
Jin yang.