Re: [PATCH RFC 0/3] firmware: arm_firme: introduce FIRME support for host attestation

[Jason Gunthorpe]

On Tue, Oct 20, 2026 at 03:43:47PM +0100, Yeoreum Yun wrote:
> On Tue, Oct 20, 2026 at 11:36:20AM -0300, Jason Gunthorpe wrote:
> > On Tue, Oct 20, 2026 at 03:13:19PM +0100, Yeoreum Yun wrote:
> > > > I wouldn't over complicated it. We already have smccc bus to do this,
> > > > we don't need layered stacks of busses here. Just change smccc bus to
> > > > be able to break up the multi-function SMC into several devices.
> > > 
> > > I think my explaination was poor. Apologise...
> > > I'm not saying another bus making but just wrapper of smccc-bus APIs
> > > for firme specific and definietly, this would separate the
> > > multi-function SMC to defien each firme device (attestation and IDE).
> > 
> > I don't see that kind of complexity is necessary.. I think it is
> > better to just have the root smcc bus spawn them 
> > 
> > > But, the *base* is common. and I couldn't find any proper location to
> > > deploy *common* code unless making arm_firme.
> > 
> > What common code excatly?
> > 
> > There shouldn't be? Getting an attestation is entirely orthogonal to
> > set link ide, for example?
> > 
> > If you can identify what you think would ever be common that might
> > help clarifgy what to do..
> 
> I mean the BASE service of firme and typical example is shared buffer
> allocation. I agree IDE and attestaion service are orthogonal. but
> in case of base-service is not. it could be used for both service.

It doesn't look like it needs a "shared buffer", just allocate it
right before invoking the SMC that needs the memory. Use a simple
library function to help allocate it. No need for a struct device
layer.

Jason