Re: [PATCH v1 25/29] cxl/amd: Enable Zen5 address translation using ACPI PRMT

From: Jonathan Cameron
Date: Fri Jan 17 2025 - 06:46:56 EST


On Fri, 17 Jan 2025 08:59:00 +0100
Robert Richter <rrichter@xxxxxxx> wrote:

> On 14.01.25 11:13:07, Jonathan Cameron wrote:
> > On Thu, 9 Jan 2025 11:14:46 +0100
> > Robert Richter <rrichter@xxxxxxx> wrote:
> >
> > > On 08.01.25 10:48:23, Gregory Price wrote:
> > >
> > > > > diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
> > > > > index 901555bf4b73..c8176265c15c 100644
> > > > > --- a/drivers/cxl/core/port.c
> > > > > +++ b/drivers/cxl/core/port.c
> > > > > @@ -831,6 +831,11 @@ static void cxl_debugfs_create_dport_dir(struct cxl_dport *dport)
> > > > > &cxl_einj_inject_fops);
> > > > > }
> > > > >
> > > > > +static void cxl_port_platform_setup(struct cxl_port *port)
> > > > > +{
> > > > > + cxl_port_setup_amd(port);
> > > > > +}
> > > > > +
> > > >
> > > > Assuming this gets expanded (which it may not), should we expect this
> > > > function to end up like so?
> > > >
> > > > static void cxl_port_platform_setup(struct cxl_port *port)
> > > > {
> > > > cxl_port_setup_amd(port);
> > > > cxl_port_setup_intel(port);
> > > > cxl_port_setup_arm(port);
> > > > ... etc ...
> > > > }
> > > >
> > > > I suppose this logic has to exist somewhere in some form, just want to make
> > > > sure this is what we want. Either way, this is easily modifiable, so
> > > > not a blocker as I said.
> > >
> > > Yes, it is exactly designed like that. I will update the patch
> > > description.
> >
> > If we need it on ARM then we might wrap this in an arch_cxl_port_platform_setup()
> > as never building a kernel that does x86 and arm. Could rely on stubs but that
> > tends to get ugly as things grow.
>
> I could move the function and file to core/x86/amd.c already and add
> a:
>
> void __weak arch_cxl_port_platform_setup(struct cxl_port *port) { }
Something like that probably makes sense. I don't like x86 calls in what
I'm building for arm, even if they are stubbed out ;)

Jonathan

>
> -Robert