Re: [RESEND v13 14/25] cxl/pci: Map CXL Endpoint Port and CXL Switch Port RAS registers

From: Jonathan Cameron
Date: Tue Nov 04 2025 - 13:19:40 EST


On Tue, 4 Nov 2025 11:02:54 -0600
Terry Bowman <terry.bowman@xxxxxxx> wrote:

> CXL Endpoint (EP) Ports may include Root Ports (RP) or Downstream Switch
> Ports (DSP). CXL RPs and DSPs contain RAS registers that require memory
> mapping to enable RAS logging. This initialization is currently missing and
> must be added for CXL RPs and DSPs.
>
> Update cxl_dport_init_ras_reporting() to support RP and DSP RAS mapping.
> Add alongside the existing Restricted CXL Host Downstream Port RAS mapping.
>
> Update cxl_endpoint_port_probe() to invoke cxl_dport_init_ras_reporting().
> This will initiate the RAS mapping for CXL RPs and DSPs when each CXL EP is
> created and added to the EP port.
>
> Make a call to cxl_port_setup_regs() in cxl_port_add(). This will probe the
> Upstream Port's CXL capabilities' physical location to be used in mapping
> the RAS registers.
>
> Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx>
Reviewed-by: Jonathan Cameron <jonathan.cameron@xxxxxxxxxx>