[U-Boot] [PATCH 0/3] Ethernet support for QEMU sifive_u machine

[Bin Meng]

Hi Anup,

On Wed, Dec 19, 2018 at 12:41 PM Anup Patel <anup at brainfault.org> wrote:
>
> On Tue, Dec 18, 2018 at 4:06 PM Bin Meng <bmeng.cn at gmail.com> wrote:
> >
> > Hi Anup,
> >
> > On Tue, Dec 18, 2018 at 6:33 PM Anup Patel <anup at brainfault.org> wrote:
> > >
> > > On Tue, Dec 18, 2018 at 3:21 PM Bin Meng <bmeng.cn at gmail.com> wrote:
> > > >
> > > > Hi Anup,
> > > >
> > > > On Mon, Dec 17, 2018 at 7:51 PM Anup Patel <anup at brainfault.org> wrote:
> > > > >
> > > > > This patchset enables Cadance MACB ethernet driver for
> > > > > QEMU sifive_u machine. The Cadance MACB ethernet driver
> > > > > works fine for QEMU sifive_u machince in both M-mode and
> > > > > S-mode with some minor fixes.
> > > > >
> > > > > The patches are based upon latest RISC-V U-Boot tree
> > > > > (git://git.denx.de/u-boot-riscv.git) at commit id
> > > > > 9deb8d2fcd13d4a40a4e63c396fe4376af46efac
> > > > >
> > > > > To try on QEMU, please ensure following patches are
> > > > > applied to QEMU sources:
> > > > > https://patchwork.kernel.org/patch/10729579/
> > > > > https://patchwork.kernel.org/patch/10729581/
> > > > >
> > > >
> > > > What "-device " parameter should I tell QEMU to instantiate the MACB?
> > > > "-device ?" does not give me anything that looks like MACB. Without a
> > > > proper "-device " parameter, I can boot U-Boot on QEMU sifive_u and
> > > > see U-Boot driver is probed, but a simple 'ping' test does not work.
> > >
> > > Try the following:
> > > # setenv ipaddr 10.0.2.1
> > > # ping 10.0.2.2
> > >
> >
> > Yes, I have set up all the required network parameters.
> >
> > > The above works for me on QEMU.
> >
> > My understanding is that we need enable QEMU network via "-netdev "
> > (either usr, or tap), with a corresponding "-device". I don't know how
> > to set it up. What's your command line to test this?
> >
>
> "-netdev" or "-device" parameters are not mandatory. By default, virtual
> NICs are in NAT mode. The QEMU NAT gateway is at IP address
> 10.0.2.2. We can always ping the NAT gateway when virtual NIC is in
> NAT mode.
>
> Here's how I compile for M-mode:
> # ARCH=riscv
> # CROSS_COMPILE=riscv64-unknown-linux-gnu-
> # make qemu-riscv64_defconfig
> # make
>
> My U-boot log is as follows:
>
> anup at anup-ubuntu64:~/Work/riscv-test/u-boot$ qemu-system-riscv64 -M
> sifive_u -m 256M -display none -serial stdio -kernel ./u-boot
>
>
> U-Boot 2019.01-rc1-00948-ge6b3cdafd0 (Dec 19 2018 - 10:05:50 +0530)
>
> CPU:   rv64imafdcsu
> Model: ucbbar,spike-bare,qemu
> DRAM:  256 MiB
> In:    uart at 10013000
> Out:   uart at 10013000
> Err:   uart at 10013000
> Net:
> Warning: ethernet at 100900fc (eth0) using random MAC address - f6:1f:8c:13:83:c0
> eth0: ethernet at 100900fc
> Hit any key to stop autoboot:  0
>
> Device 0: unknown device
> ethernet at 100900fc: PHY present at 0
> ethernet at 100900fc: link up, 100Mbps full-duplex (lpa: 0xcde1)
> BOOTP broadcast 1
> DHCP client bound to address 10.0.2.15 (2 ms)
> Using ethernet at 100900fc device
> TFTP from server 10.0.2.2; our IP address is 10.0.2.15
> Filename 'boot.scr.uimg'.
> Load address: 0x82100000
> Loading: *
> TFTP error: 'Access violation' (2)
> Not retrying...
> ethernet at 100900fc: PHY present at 0
> ethernet at 100900fc: link up, 100Mbps full-duplex (lpa: 0xcde1)
> BOOTP broadcast 1
> DHCP client bound to address 10.0.2.15 (1 ms)
> Using ethernet at 100900fc device
> TFTP from server 10.0.2.2; our IP address is 10.0.2.15
> Filename 'boot.scr.uimg'.
> Load address: 0x81000000
> Loading: *
> TFTP error: 'Access violation' (2)
> Not retrying...
> => ping 10.0.2.2
> ethernet at 100900fc: PHY present at 0
> ethernet at 100900fc: link up, 100Mbps full-duplex (lpa: 0xcde1)
> Using ethernet at 100900fc device
> host 10.0.2.2 is alive
> =>
> ethernet at 100900fc: PHY present at 0
> ethernet at 100900fc: link up, 100Mbps full-duplex (lpa: 0xcde1)
> Using ethernet at 100900fc device
> host 10.0.2.2 is alive
> => qemu-system-riscv64: terminating on signal 2
>

I have always been using "qemu-system-riscv64 -nographic -M sifive_u
-kernel u-boot" to test U-Boot on qemu risc-v.
With above command, I can "ping 10.0.2.2" and get the exact the same
result as yours.

However I wanted to connect the tap interface to the emulated network
controller for testing, that's why I wanted to use "-device" and
"-netdev", but I don't know which device string I need to tell QEMU.
After a bit googleing I got the following page:
https://forums.xilinx.com/t5/Embedded-Processor-System-Design/Zynq-QEMU-Network-Issues/td-p/797050

>From the page it looks that the device should be "-device
cadence_gem", but when I pass it to QEMU I got:

qemu-system-riscv64: -device cadence_gem,netdev=net0: Parameter
'driver' expects pluggable device type

It looks cadence_gem is not a pluggable device. Any ideas?

Regards,
Bin