Subject: Re: [PATCH v6 16/28] sfc: obtain root decoder with enough HPA free space

From: Martin Habets <[email-masked]>
Date: Tue, 3 Dec 2024 14:34:08 +0000

On Mon, Dec 02, 2024 at 05:12:10PM +0000, [email-masked] wrote:
> 
> From: Alejandro Lucero <[email-masked]>
> 
> Asking for availbale HPA space is the previous step to try to obtain
> an HPA range suitable to accel driver purposes.
> 
> Add this call to efx cxl initialization.
> 
> Signed-off-by: Alejandro Lucero <[email-masked]>

Reviewed-by: Martin Habets <[email-masked]>
One comment below.

> ---
>  drivers/net/ethernet/sfc/efx_cxl.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/net/ethernet/sfc/efx_cxl.c b/drivers/net/ethernet/sfc/efx_cxl.c
> index d03fa9f9c421..79b93d92f9c2 100644
> --- a/drivers/net/ethernet/sfc/efx_cxl.c
> +++ b/drivers/net/ethernet/sfc/efx_cxl.c
> @@ -26,6 +26,7 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
>  	struct pci_dev *pci_dev;
>  	struct efx_cxl *cxl;
>  	struct resource res;
> +	resource_size_t max;
>  	u16 dvsec;
>  	int rc;
>  
> @@ -102,6 +103,23 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
>  		goto err3;
>  	}
>  
> +	cxl->cxlrd = cxl_get_hpa_freespace(cxl->cxlmd,
> +					   CXL_DECODER_F_RAM | CXL_DECODER_F_TYPE2,
> +					   &max);
> +
> +	if (IS_ERR(cxl->cxlrd)) {
> +		pci_err(pci_dev, "cxl_get_hpa_freespace failed\n");
> +		rc = PTR_ERR(cxl->cxlrd);
> +		goto err3;
> +	}
> +
> +	if (max < EFX_CTPIO_BUFFER_SIZE) {
> +		pci_err(pci_dev, "%s: no enough free HPA space %llu < %u\n",
> +			__func__, max, EFX_CTPIO_BUFFER_SIZE);

Seems it should use %pa[p] for max here.

Martin

> +		rc = -ENOSPC;
> +		goto err3;
> +	}
> +
>  	probe_data->cxl = cxl;
>  	return 0;
> -- 
> 2.17.1