Re: [PATCH v24 09/11] sfc: obtain decoder and region if committed by firmware

Dave Jiang
2026-03-24T17:38:16Z

On 3/23/26 4:31 AM, alejandro.lucero-palau@amd.com wrote:
> From: Alejandro Lucero <alucerop@amd.com>
>
> Check if device HDM is already committed during firmware/BIOS
> initialization.
>
> A CXL region should exist if so after memdev allocation/initialization.
> Get HPA from region and map it.
>
> Signed-off-by: Alejandro Lucero <alucerop@amd.com>
> Acked-by: Edward Cree <ecree.xilinx@gmail.com>
> ---
> drivers/net/ethernet/sfc/efx_cxl.c | 24 ++++++++++++++++++++++++
> 1 file changed, 24 insertions(+)
>
> diff --git a/drivers/net/ethernet/sfc/efx_cxl.c b/drivers/net/ethernet/sfc/efx_cxl.c
> index 22a7d1d95425..78f926300943 100644
> --- a/drivers/net/ethernet/sfc/efx_cxl.c
> +++ b/drivers/net/ethernet/sfc/efx_cxl.c
> @@ -19,6 +19,7 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
> struct efx_nic *efx = &probe_data->efx;
> struct pci_dev *pci_dev = efx->pci_dev;
> struct efx_cxl *cxl;
> + struct range range;
> u16 dvsec;
> int rc;
>
> @@ -82,6 +83,24 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
> return PTR_ERR(cxl->cxlmd);
> }
>
> + cxl->cxled = cxl_get_committed_decoder(cxl->cxlmd, &cxl->efx_region);
> + if (!cxl->cxled || !cxl->efx_region)
> + return -ENODEV;
> +
> + rc = cxl_get_region_range(cxl->efx_region, &range);
> + if (rc) {
> + pci_err(pci_dev,
> + "CXL getting regions params from a committed decoder failed");
> + return rc;
> + }
> +
> + cxl->ctpio_cxl = ioremap(range.start, range_len(&range));
> + if (!cxl->ctpio_cxl) {
> + pci_err(pci_dev, "CXL ioremap region (%pra) failed", &range);
> + return -ENOMEM;
> + }
> +
> +
> probe_data->cxl = cxl;
>
> return 0;
> @@ -89,6 +108,11 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
>
> void efx_cxl_exit(struct efx_probe_data *probe_data)
> {
> + if (!probe_data->cxl)
> + return;
> +
> + iounmap(probe_data->cxl->ctpio_cxl);
> + cxl_unregister_region(probe_data->cxl->efx_region);

Would a device_put() on the region dev be sufficient here? Not sure if everything should be torn down if SFC didn't create the region to begin with and only retrieved it via cxl_get_commited_decoder()?

DJ

> }
>
> MODULE_IMPORT_NS("CXL");