Re: [Qemu-devel] [RFC PATCH 0/2] hw/char/bcm2835_aux: Provide full 16550 UART support

[Philippe Mathieu-Daudé]

On 8/20/19 2:34 PM, Philippe Mathieu-Daudé wrote:
> Hi,
> 
> Since there has been some activity on the list asking about
> Rasberry PI USB support, I had a look a some previous unfinished
> work and rebased it to share, in case it helps hobbyist interested
> in improving these machines.
> 
> This series is some proof-of-concept on improving the AUX UART
> support. See the commit description for various TODO/questions.
> 
> This can be tested using files documented by Peter Maydell in
> his blog post:
> https://translatedcode.wordpress.com/2018/04/25/debian-on-qemus-raspberry-pi-3-model/
> 
> And using the kernel command line arguments suggested by Guenter Roeck:
> 
> qemu-system-aarch64 -M raspi3 -m 1024 \
>   -kernel raspi3/bootpart/vmlinuz-4.14.0-3-arm64 \
>   -initrd raspi3/bootpart/initrd.img-4.14.0-3-arm64 \
>   -dtb raspi3/bootpart/bcm2837-rpi-3-b.dtb \
>   -append 'earlycon=uart8250,mmio32,0x3f215040 rdinit=/sbin/init panic=-1 
> console=ttyS1,115200' \
>   -drive 
> file=raspi3/2018-01-08-raspberry-pi-3-buster-PREVIEW.img,format=raw,if=sd \
>   -serial null -serial stdio \
>   -d unimp,guest_errors -trace bcm283\*
[...]
I forgot to add: the difference with what we have now, is all these
registers get now properly implemented:

bcm2836_control_write: Bad offset 0
bcm2836_control_write: Bad offset 8
bcm2835_aux_write: AUX_MU_MCR_REG unsupported
bcm2835_aux_write: AUX_MU_LCR_REG unsupported
bcm2835_aux_write: AUX_MU_LCR_REG unsupported
bcm2835_aux_write: AUX_MU_MCR_REG unsupported
bcm2835_property: unhandled tag 00030030
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_LCR_REG unsupported
bcm2835_aux_read: AUX_MU_LCR_REG unsupported
bcm2835_aux_write: AUX_MU_LCR_REG unsupported
bcm2835_aux_write: AUX_MU_MCR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_write: AUX_MU_LCR_REG unsupported
bcm2835_aux_write: AUX_MU_LCR_REG unsupported
bcm2835_aux_write: AUX_MU_MCR_REG unsupported
bcm2835_aux_write: AUX_MU_MCR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported
bcm2835_aux_read: AUX_MU_MSR_REG unsupported

(log booting the same image without this series).