Subject: Re: [PATCH v8 07/27] sfc: use cxl api for regs setup and checking

From: Jonathan Cameron <[email-masked]>
Date: Tue, 24 Dec 2024 17:23:59 +0000

On Mon, 16 Dec 2024 16:10:22 +0000
[email-masked] wrote:

> From: Alejandro Lucero <[email-masked]>
> 
> Use cxl code for registers discovery and mapping.
> 
> Validate capabilities found based on those registers against expected
> capabilities.
> 
> Signed-off-by: Alejandro Lucero <[email-masked]>
> Reviewed-by: Martin Habets <[email-masked]>
> Reviewed-by: Zhi Wang <[email-masked]>
> Acked-by: Edward Cree <[email-masked]>
Similar comments to on the earlier bitmap manipulation.
It is simpler than you have here!

Jonathan

> ---
>  drivers/net/ethernet/sfc/efx_cxl.c | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/drivers/net/ethernet/sfc/efx_cxl.c b/drivers/net/ethernet/sfc/efx_cxl.c
> index 356d7a977e1c..d9a52343553a 100644
> --- a/drivers/net/ethernet/sfc/efx_cxl.c
> +++ b/drivers/net/ethernet/sfc/efx_cxl.c
> @@ -21,6 +21,8 @@
>  int efx_cxl_init(struct efx_probe_data *probe_data)
>  {
>  	struct efx_nic *efx = &probe_data->efx;
> +	DECLARE_BITMAP(expected, CXL_MAX_CAPS);
> +	DECLARE_BITMAP(found, CXL_MAX_CAPS);
>  	struct pci_dev *pci_dev;
>  	struct efx_cxl *cxl;
>  	struct resource res;
> @@ -65,6 +67,24 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
>  		goto err_resource_set;
>  	}
>  
> +	rc = cxl_pci_accel_setup_regs(pci_dev, cxl->cxlds);
> +	if (rc) {
> +		pci_err(pci_dev, "CXL accel setup regs failed");
> +		goto err_resource_set;
> +	}
> +
> +	bitmap_clear(expected, 0, CXL_MAX_CAPS);
> +	bitmap_set(expected, CXL_DEV_CAP_HDM, 1);
set_bit()

> +	bitmap_set(expected, CXL_DEV_CAP_RAS, 1);
> +
> +	if (!cxl_pci_check_caps(cxl->cxlds, expected, found)) {
> +		pci_err(pci_dev,
> +			"CXL device capabilities found(%08lx) not as expected(%08lx)",

bitmap format strings, not dereferencing the unsigned longs.

> +			*found, *expected);
> +		rc = -EIO;
> +		goto err_resource_set;
> +	}
> +
>  	probe_data->cxl = cxl;
>  	return 0;