Re: [PATCH 0/5] Add initial Bitmain BM1880 SoC/Board support

[Manivannan Sadhasivam]

Hi Andrew,

On Sat, Jan 26, 2019 at 04:03:20PM +0100, Andrew Lunn wrote:
> On Sat, Jan 26, 2019 at 09:40:36AM +0530, Manivannan Sadhasivam wrote:
> > Hello,
> > 
> > This patchset adds initial support for Bitmain BM1880 SoC and Sophon
> > Edge board. BM1880 SoC consists of a Dual Core ARM Cortex A53 Application
> > processor subsystem, a single core RISC-V subsystem and a Tensor
> > Processor subsystem.
> 
> Hi Manivannan
> 
> Interesting combination of CPUs. 
> 
> > This patchset adds support for only ARM Cortex A53 Application
> > processor subsystem with UART, which enables the board to boot into
> > initramfs with 2 CPUs.
> 
> Looking forward, what sharing do you expect at the device tree level?
> 
> Looking at 
> 
> https://sophon-file.bitmain.com.cn/sophon-prod/drive/18/11/06/19/BM1880%20product%20brief%20V0.04_Chinese%20versionV0.06.pdf
> 
> it appears all the devices can be shared between the CPUs. So do you
> plan to have a shared .dtsi file somewhere? 
> 
> Is ARCH_BITMAIN going to be both ARM64 and RISC-V?
> 

We don't have any plan to add support for RISC-V subsystem. Moreover,
from the SoC product brief it look like the RISC-V core is a MCU grade
core, so I doubt whether we can run linux on it! It might be a candidate
for RTOS.

For now, ARCH_BITMAIN is going to have only ARM64 support.

Thanks,
Mani

>    Thanks
> 	Andrew