Re: [PATCH v2 07/38] cxlflash: Setup function acTag range

Frederic Barrat
2018-03-22T15:48:36Z

Le 26/02/2018 à 23:20, Uma Krishnan a écrit :
> The OCXL specification supports distributing acTags amongst different
> AFUs and functions on the link. The platform-specific acTag range for the
> link is obtained using the OCXL provider services and then assigned to the
> host function based on implementation. For cxlflash devices only a single
> function per host is expected and thus the entire range is assigned.
>
> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
> ---
> drivers/scsi/cxlflash/ocxl_hw.c | 15 +++++++++++++++
> drivers/scsi/cxlflash/ocxl_hw.h | 3 +++
> 2 files changed, 18 insertions(+)
>
> diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
> index dc32a73..39cccb7 100644
> --- a/drivers/scsi/cxlflash/ocxl_hw.c
> +++ b/drivers/scsi/cxlflash/ocxl_hw.c
> @@ -42,6 +42,7 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
> {
> struct ocxl_fn_config *fcfg = &afu->fcfg;
> struct device *dev = &pdev->dev;
> + u16 base, enabled, supported;
> int rc = 0;
>
> /* Read DVSEC config of the function */
> @@ -56,6 +57,20 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
> if (fcfg->max_afu_index != 0)
> dev_warn(dev, "%s: Unexpected AFU index value %d\n",
> __func__, fcfg->max_afu_index);
> +
> + rc = ocxl_config_get_actag_info(pdev, &base, &enabled, &supported);
> + if (unlikely(rc)) {
> + dev_err(dev, "%s: ocxl_config_get_actag_info failed rc=%d\n",
> + __func__, rc);
> + goto out;
> + }
> +
> + afu->fn_actag_base = base;
> + afu->fn_actag_enabled = enabled;
> +

Since you know your configuration (only 1 function with AFU, all actags
to that AFU), you could even have a warning if supported != enabled, to
detect suspicious AFU images.

Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>

> + ocxl_config_set_actag(pdev, fcfg->dvsec_function_pos, base, enabled);
> + dev_dbg(dev, "%s: Function acTag range base=%u enabled=%u\n",
> + __func__, base, enabled);
> out:
> return rc;
> }
> diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
> index 658f420..190d71a 100644
> --- a/drivers/scsi/cxlflash/ocxl_hw.h
> +++ b/drivers/scsi/cxlflash/ocxl_hw.h
> @@ -18,4 +18,7 @@ struct ocxl_hw_afu {
> struct device *dev; /* Generic device */
>
> struct ocxl_fn_config fcfg; /* DVSEC config of the function */
> +
> + int fn_actag_base; /* Function acTag base */
> + int fn_actag_enabled; /* Function acTag number enabled */
> };
>