Re: [Intel-xe] [PATCH 1/3] drm/xe: Introduce a module parameter to control XeLink

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Tue, Aug 08, 2023 at 12:45:32PM -0400, David Kershner wrote:
> Add a new module parameter to control enable/disable of the XeLink
> feature.
> 
> Signed-off-by: David Kershner <david.kershner@intel.com>

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

> ---
>  drivers/gpu/drm/xe/Makefile    |  3 ++-
>  drivers/gpu/drm/xe/xe_xelink.c | 17 +++++++++++++++++
>  2 files changed, 19 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/gpu/drm/xe/xe_xelink.c
> 
> diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
> index 1b59702cd9f9..d46558cf12a9 100644
> --- a/drivers/gpu/drm/xe/Makefile
> +++ b/drivers/gpu/drm/xe/Makefile
> @@ -115,7 +115,8 @@ xe-y += xe_bb.o \
>  	xe_vm_madvise.o \
>  	xe_wait_user_fence.o \
>  	xe_wa.o \
> -	xe_wopcm.o
> +	xe_wopcm.o \
> +	xe_xelink.o
>  
>  # i915 Display compat #defines and #includes
>  subdir-ccflags-$(CONFIG_DRM_XE_DISPLAY) += \
> diff --git a/drivers/gpu/drm/xe/xe_xelink.c b/drivers/gpu/drm/xe/xe_xelink.c
> new file mode 100644
> index 000000000000..51a31f6a4740
> --- /dev/null
> +++ b/drivers/gpu/drm/xe/xe_xelink.c
> @@ -0,0 +1,17 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright © 2023 Intel Corporation
> + */
> +
> +#include <linux/moduleparam.h>
> +
> +/*
> + * This module parameter is needed because SRIOV PF and XeLink are mutually
> + * exclusive. The driver needs to be able to enable/disable the XeLink
> + * infrastructure (specifically Device Physical Addressing).  Since there
> + * will be no enable/disable for the SRIOV PF path, this parameter is
> + * needed to explicitly disable XeLink when SRIOV PF is required.
> + */
> +static bool xe_enable_xelink = true;
> +module_param_named(enable_xelink, xe_enable_xelink, bool, 0400);
> +MODULE_PARM_DESC(enable_xelink, "Enable XeLink feature (default: true)");
> -- 
> 2.35.1
>