Subject: Re: [PATCH v10 02/26] sfc: add basic cxl initialization

From: Simon Horman <[email-masked]>
Date: Tue, 18 Feb 2025 13:32:27 +0000

On Mon, Feb 17, 2025 at 01:11:41PM +0000, Alejandro Lucero Palau wrote:
> 
> On 2/7/25 13:03, Simon Horman wrote:
> > On Wed, Feb 05, 2025 at 03:19:26PM +0000, [email-masked] wrote:
> > > From: Alejandro Lucero <[email-masked]>
> > > 
> > > Create a cxl_memdev_state with CXL_DEVTYPE_DEVMEM, aka CXL Type2 memory
> > > device.
> > > 
> > > Make sfc CXL initialization dependent on kernel CXL configuration.
> > > 
> > > Signed-off-by: Alejandro Lucero <[email-masked]>
> > > ---
> > >   drivers/net/ethernet/sfc/Kconfig      |  5 +++
> > >   drivers/net/ethernet/sfc/Makefile     |  1 +
> > >   drivers/net/ethernet/sfc/efx.c        | 16 ++++++-
> > >   drivers/net/ethernet/sfc/efx_cxl.c    | 60 +++++++++++++++++++++++++++
> > >   drivers/net/ethernet/sfc/efx_cxl.h    | 40 ++++++++++++++++++
> > >   drivers/net/ethernet/sfc/net_driver.h | 10 +++++
> > >   6 files changed, 131 insertions(+), 1 deletion(-)
> > >   create mode 100644 drivers/net/ethernet/sfc/efx_cxl.c
> > >   create mode 100644 drivers/net/ethernet/sfc/efx_cxl.h
> > > 
> > > diff --git a/drivers/net/ethernet/sfc/Kconfig b/drivers/net/ethernet/sfc/Kconfig
> > > index 3eb55dcfa8a6..0ce4a9cd5590 100644
> > > --- a/drivers/net/ethernet/sfc/Kconfig
> > > +++ b/drivers/net/ethernet/sfc/Kconfig
> > > @@ -65,6 +65,11 @@ config SFC_MCDI_LOGGING
> > >   	  Driver-Interface) commands and responses, allowing debugging of
> > >   	  driver/firmware interaction.  The tracing is actually enabled by
> > >   	  a sysfs file 'mcdi_logging' under the PCI device.
> > > +config SFC_CXL
> > > +	bool "Solarflare SFC9100-family CXL support"
> > > +	depends on SFC && CXL_BUS && !(SFC=y && CXL_BUS=m)
> > > +	depends on CXL_BUS >= CXL_BUS
> > Hi Alejandro,
> > 
> > I'm confused by the intent of the line above.
> > Could you clarify?
> 
> 
> Dan original comments will do:
> 
> https://lore.kernel.org/all/[email-masked]/

Thanks, that makes things a bit clearer.
But do you mean:

 depends on CXL_BUS >= SFC

Rather than:

 depends on CXL_BUS >= CXL_BUS

Because the line above appears to be a truism.

> 
> 
> > > +	default SFC
> > >   source "drivers/net/ethernet/sfc/falcon/Kconfig"
> > >   source "drivers/net/ethernet/sfc/siena/Kconfig"
> > ...
>