Re: [PATCH v3 3/4] hw/arm: sabrelite: Connect the Ethernet PHY at address 6

[Guenter Roeck <linux@roeck-us.net>]

Hi,

On Wed, Jan 06, 2021 at 02:35:03PM +0800, Bin Meng wrote:
> From: Bin Meng <bin.meng@windriver.com>
> 
> At present, when booting U-Boot on QEMU sabrelite, we see:
> 
>   Net:   Board Net Initialization Failed
>   No ethernet found.
> 
> U-Boot scans PHY at address 4/5/6/7 (see board_eth_init() in the
> U-Boot source: board/boundary/nitrogen6x/nitrogen6x.c). On the real
> board, the Ethernet PHY is at address 6. Adjust this by updating the
> "fec-phy-num" property of the fsl_imx6 SoC object.
> 
> With this change, U-Boot sees the PHY but complains MAC address:
> 
>   Net:   using phy at 6
>   FEC [PRIME]
>   Error: FEC address not set.
> 
> This is due to U-Boot tries to read the MAC address from the fuse,
> which QEMU does not have any valid content filled in. However this
> does not prevent the Ethernet from working in QEMU. We just need to
> set up the MAC address later in the U-Boot command shell, by:
> 
>   => setenv ethaddr 00:11:22:33:44:55
> 

With this patch in place, the standard Ethernet interface no longer works when
booting sabrelite Linux images directly (without u-boot) using the following
qemu command.
	qemu-system-arm -M sabrelite -kernel arch/arm/boot/zImage
	...

The Ethernet interface still instantiates, but packet transfer to the host
no longer works. Reverting this patch fixes the problem for me.

Is there a qemu command line parameter that is now necessary to instantiate
the Ethernet interface when booting Linux ?

Thanks,
Guenter