Re: [PATCH 08/14] cxl/mem: Skip range enumeration if mem_enable clear

From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
To: Dan Williams <dan.j.williams@intel.com>
Cc: <linux-cxl@vger.kernel.org>, <ben.widawsky@intel.com>,
	<ira.weiny@intel.com>, <alison.schofield@intel.com>,
	<vishal.l.verma@intel.com>
Subject: Re: [PATCH 08/14] cxl/mem: Skip range enumeration if mem_enable clear
Date: Wed, 18 May 2022 18:25:27 +0100	[thread overview]
Message-ID: <20220518182527.00002c69@huawei.com> (raw)
In-Reply-To: <165237929979.3832067.5582691867405954753.stgit@dwillia2-desk3.amr.corp.intel.com>

On Thu, 12 May 2022 11:14:59 -0700
Dan Williams <dan.j.williams@intel.com> wrote:

> When a device does not have mem_enable set then the current range
> settings are moot. Skip the enumeration and cause cxl_hdm_decode_init()
> to proceed directly to enable the HDM Decoder Capability.
> 
> Fixes: 560f78559006 ("cxl/pci: Retrieve CXL DVSEC memory info")
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/cxl/core/pci.c |    2 ++
>  drivers/cxl/mem.c      |    2 +-
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index ea6711721901..f3e59f8b6621 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -224,6 +224,8 @@ int cxl_dvsec_ranges(struct cxl_dev_state *cxlds,
>  	}
>  
>  	info->mem_enabled = FIELD_GET(CXL_DVSEC_MEM_ENABLE, ctrl);
> +	if (!info->mem_enabled)
> +		return 0;
>  
>  	for (i = 0; i < hdm_count; i++) {
>  		u64 base, size;
> diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
> index 0cfbde134fc7..902d1f6e189e 100644
> --- a/drivers/cxl/mem.c
> +++ b/drivers/cxl/mem.c
> @@ -92,7 +92,7 @@ __mock bool cxl_hdm_decode_init(struct cxl_dev_state *cxlds,
>  	 * are expected even though Linux does not require or maintain that
>  	 * match.
>  	 */
> -	if (!global_enable && info->ranges)
> +	if (!global_enable && info->mem_enabled && info->ranges)
>  		goto out;
>  
>  	retval = true;
>