Subject: Re: [PATCH v18 20/20] sfc: support pio mapping based on cxl

From: Jonathan Cameron <[email-masked]>
Date: Thu, 18 Sep 2025 16:08:32 +0100

A few trivial things inline.

> diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c
> index 47349c148c0c..7bc854e2d22a 100644
> --- a/drivers/net/ethernet/sfc/ef10.c
> +++ b/drivers/net/ethernet/sfc/ef10.c

> diff --git a/drivers/net/ethernet/sfc/efx_cxl.c b/drivers/net/ethernet/sfc/efx_cxl.c
> index 85490afc7930..3dde59003cd9 100644
> --- a/drivers/net/ethernet/sfc/efx_cxl.c
> +++ b/drivers/net/ethernet/sfc/efx_cxl.c
> @@ -11,16 +11,23 @@
>  
>  #include "net_driver.h"
>  #include "efx_cxl.h"
> +#include "efx.h"
>  
>  #define EFX_CTPIO_BUFFER_SIZE	SZ_256M
>  
>  static void efx_release_cxl_region(void *priv_cxl)
>  {
>  	struct efx_probe_data *probe_data = priv_cxl;
> +	struct efx_nic *efx = &probe_data->efx;
>  	struct efx_cxl *cxl = probe_data->cxl;
>  
> +	/* Next avoid contention with efx_cxl_exit() */
>  	probe_data->cxl_pio_initialised = false;
> +
> +	/* Next makes cxl-based piobus to no be used */
> +	efx_ef10_disable_piobufs(efx);
>  	iounmap(cxl->ctpio_cxl);
> +

Avoid extra white space changes. Perhaps push to earlier patch.

>  	cxl_put_root_decoder(cxl->cxlrd);
>  }
>  
> @@ -30,6 +37,7 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
>  	struct pci_dev *pci_dev = efx->pci_dev;
>  	resource_size_t max_size;
>  	struct efx_cxl *cxl;
> +	struct range range;
>  	u16 dvsec;
>  	int rc;
>  
> @@ -133,17 +141,34 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
>  					    &probe_data);
>  	if (IS_ERR(cxl->efx_region)) {
>  		pci_err(pci_dev, "CXL accel create region failed");
> -		cxl_dpa_free(cxl->cxled);
>  		rc = PTR_ERR(cxl->efx_region);
> -		goto err_decoder;
> +		goto err_dpa;

Why do we now need to call cxl_dpa_free() and didn't previously here? That
seems like a probably bug in earlier patch.

> +	}
> +
> +	rc = cxl_get_region_range(cxl->efx_region, &range);
> +	if (rc) {
> +		pci_err(pci_dev, "CXL getting regions params failed");
> +		goto err_detach;
> +	}
> +
> +	cxl->ctpio_cxl = ioremap(range.start, range.end - range.start + 1);
> +	if (!cxl->ctpio_cxl) {
> +		pci_err(pci_dev, "CXL ioremap region (%pra) failed", &range);
> +		rc = -ENOMEM;
> +		goto err_detach;
>  	}
>  
>  	probe_data->cxl = cxl;
> +	probe_data->cxl_pio_initialised = true;
>  
>  	cxl_release_endpoint(cxl->cxlmd, cxl->endpoint);
>  
>  	return 0;
>  
> +err_detach:
> +	cxl_decoder_detach(NULL, cxl->cxled, 0, DETACH_INVALIDATE);
> +err_dpa:
> +	cxl_dpa_free(cxl->cxled);
>  err_decoder:
>  	cxl_put_root_decoder(cxl->cxlrd);
>  err_release:
> @@ -154,7 +179,8 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
>  
>  void efx_cxl_exit(struct efx_probe_data *probe_data)
>  {
> -	if (probe_data->cxl) {
> +	if (probe_data->cxl_pio_initialised) {
> +		iounmap(probe_data->cxl->ctpio_cxl);
>  		cxl_decoder_detach(NULL, probe_data->cxl->cxled, 0,
>  				   DETACH_INVALIDATE);
>  		cxl_dpa_free(probe_data->cxl->cxled);