Re: [PATCH v4 29/42] hw/cxl/host: Add support for CXL Fixed Memory Windows.

[Jonathan Cameron]

On Tue, 25 Jan 2022 17:02:32 +0000
Alex Bennée <alex.bennee@linaro.org> wrote:

> Jonathan Cameron <Jonathan.Cameron@huawei.com> writes:
> 
> > From: Jonathan Cameron <jonathan.cameron@huawei.com>
> >
> > The concept of these is introduced in [1] in terms of the
> > description the CEDT ACPI table. The principal is more general.
> > Unlike once traffic hits the CXL root bridges, the host system
> > memory address routing is implementation defined and effectively
> > static once observable by standard / generic system software.
> > Each CXL Fixed Memory Windows (CFMW) is a region of PA space
> > which has fixed system dependent routing configured so that
> > accesses can be routed to the CXL devices below a set of target
> > root bridges. The accesses may be interleaved across multiple
> > root bridges.  
> 
> This breaks the linux-user builds...
> > diff --git a/hw/cxl/meson.build b/hw/cxl/meson.build
> > index 0eca715d10..27dff3868b 100644
> > --- a/hw/cxl/meson.build
> > +++ b/hw/cxl/meson.build
> > @@ -1,5 +1,9 @@
> > -softmmu_ss.add(when: 'CONFIG_CXL', if_true: files(
> > -  'cxl-component-utils.c',
> > -  'cxl-device-utils.c',
> > -  'cxl-mailbox-utils.c',
> > +specific_ss.add(when: 'CONFIG_CXL', if_true: files(
> > +      'cxl-component-utils.c',
> > +      'cxl-device-utils.c',
> > +      'cxl-mailbox-utils.c',
> > +      'cxl-host.c',
> > +))
> > +specific_ss.add(when: 'CONFIG_CXL', if_false: files(
> > +      'cxl-host-stubs.c',
> >  ))  
> 
> I think you want this:
> 
>   softmmu_ss.add(when: 'CONFIG_CXL',
>                  if_true: files(
>                    'cxl-component-utils.c',
>                    'cxl-device-utils.c',
>                    'cxl-mailbox-utils.c',
>                    'cxl-host.c'),
>                  if_false: files(
>                    'cxl-host-stubs.c',
>                  ))
> 
>   # This is required as well:
>   softmmu_ss.add(when: 'CONFIG_ALL', if_true: files('cxl-host-stubs.c'))

Ah.  I'd started with the first block and got incomprehensible error
message.  Second block fixes it.

I'll not pretend to understand the 'why' :)

Thanks,

Jonathan

> 
>