[PATCH v2 3/3] drm/xe: Normalize default param values

[John Harrison]

On 6/13/2025 1:00 PM, Lucas De Marchi wrote:
> Document xe module params with the default values following a similar
> strategy for all of them:
>
> 	1) Define a DEFAULT_* macro with the default value. When the
> 	   value can't be directly stringified, also define a *_STR
> 	   variant
> 	2) Use __stringify() or the _STR variant to make sure the
> 	   default value shows up in the param description
>
> This allows us to show the correct default according to the
> configuration. max_vfs for example was wrongly documented for
> CONFIG_DRM_XE_DEBUG and svm_notifier_size didn't have its default
> documented.
>
> Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
> ---
>   drivers/gpu/drm/xe/xe_module.c | 44 +++++++++++++++++++++++++++---------------
>   1 file changed, 28 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_module.c b/drivers/gpu/drm/xe/xe_module.c
> index 192908fa074cb..2068c579d5c3b 100644
> --- a/drivers/gpu/drm/xe/xe_module.c
> +++ b/drivers/gpu/drm/xe/xe_module.c
> @@ -19,34 +19,43 @@
>   #include "xe_sched_job.h"
>   
>   #if IS_ENABLED(CONFIG_DRM_XE_DEBUG)
> -#define DEFAULT_GUC_LOG_LEVEL	3
> +#define DEFAULT_GUC_LOG_LEVEL		3
> +#define DEFAULT_MAX_VFS			~0
> +#define DEFAULT_MAX_VFS_STR		"unlimited"
>   #else
> -#define DEFAULT_GUC_LOG_LEVEL	1
> +#define DEFAULT_GUC_LOG_LEVEL		1
> +#define DEFAULT_MAX_VFS			0
> +#define DEFAULT_MAX_VFS_STR		"0"
Could be 'stringify(MAX_VFS)'.

>   #endif
>   
> +#define DEFAULT_PROBE_DISPLAY		true
> +#define DEFAULT_FORCE_PROBE		CONFIG_DRM_XE_FORCE_PROBE
> +#define DEFAULT_WEDGED_MODE		1
> +#define DEFAULT_SVM_NOTIFIER_SIZE	512
> +
>   struct xe_modparam xe_modparam = {
> -	.probe_display = true,
> -	.guc_log_level = DEFAULT_GUC_LOG_LEVEL,
> -	.force_probe = CONFIG_DRM_XE_FORCE_PROBE,
> -#ifdef CONFIG_PCI_IOV
This ifdef is lost from the new version?

> -	.max_vfs = IS_ENABLED(CONFIG_DRM_XE_DEBUG) ? ~0 : 0,
> -#endif
> -	.wedged_mode = 1,
> -	.svm_notifier_size = 512,
> +	.probe_display =	DEFAULT_PROBE_DISPLAY,
> +	.guc_log_level =	DEFAULT_GUC_LOG_LEVEL,
> +	.force_probe =		DEFAULT_FORCE_PROBE,
> +	.max_vfs =		DEFAULT_MAX_VFS,
> +	.wedged_mode =		DEFAULT_WEDGED_MODE,
> +	.svm_notifier_size =	DEFAULT_SVM_NOTIFIER_SIZE,
>   	/* the rest are 0 by default */
>   };
>   
>   module_param_named(svm_notifier_size, xe_modparam.svm_notifier_size, uint, 0600);
> -MODULE_PARM_DESC(svm_notifier_size, "Set the svm notifier size(in MiB), must be power of 2");
> +MODULE_PARM_DESC(svm_notifier_size, "Set the svm notifier size in MiB, must be power of 2 "
> +		 "[default=" __stringify(DEFAULT_SVM_NOTIFIER_SIZE) "]");
>   
>   module_param_named_unsafe(force_execlist, xe_modparam.force_execlist, bool, 0444);
>   MODULE_PARM_DESC(force_execlist, "Force Execlist submission");
>   
>   module_param_named(probe_display, xe_modparam.probe_display, bool, 0444);
> -MODULE_PARM_DESC(probe_display, "Probe display HW, otherwise it's left untouched (default: true)");
> +MODULE_PARM_DESC(probe_display, "Probe display HW, otherwise it's left untouched "
> +		 "[default=" __stringify(DEFAULT_PROBE_DISPLAY) "])");
>   
>   module_param_named(vram_bar_size, xe_modparam.force_vram_bar_size, int, 0600);
> -MODULE_PARM_DESC(vram_bar_size, "Set the vram bar size (in MiB) - <0=disable-resize, 0=max-needed-size[default], >0=force-size");
> +MODULE_PARM_DESC(vram_bar_size, "Set the vram bar size in MiB (<0=disable-resize, 0=max-needed-size, >0=force-size [default=0])");
Why leave this one as hard coded value rather than a define?

John.

>   
>   module_param_named(guc_log_level, xe_modparam.guc_log_level, int, 0600);
>   MODULE_PARM_DESC(guc_log_level, "GuC firmware logging level (0=disable, 1=normal, 2..5=verbose-levels "
> @@ -66,18 +75,21 @@ MODULE_PARM_DESC(gsc_firmware_path,
>   
>   module_param_named_unsafe(force_probe, xe_modparam.force_probe, charp, 0400);
>   MODULE_PARM_DESC(force_probe,
> -		 "Force probe options for specified devices. See CONFIG_DRM_XE_FORCE_PROBE for details.");
> +		 "Force probe options for specified devices. See CONFIG_DRM_XE_FORCE_PROBE for details "
> +		 "[default=" DEFAULT_FORCE_PROBE "])");
>   
>   #ifdef CONFIG_PCI_IOV
>   module_param_named(max_vfs, xe_modparam.max_vfs, uint, 0400);
>   MODULE_PARM_DESC(max_vfs,
>   		 "Limit number of Virtual Functions (VFs) that could be managed. "
> -		 "(0 = no VFs [default]; N = allow up to N VFs)");
> +		 "(0=no VFs; N=allow up to N VFs "
> +		 "[default=" DEFAULT_MAX_VFS_STR "])");
>   #endif
>   
>   module_param_named_unsafe(wedged_mode, xe_modparam.wedged_mode, int, 0600);
>   MODULE_PARM_DESC(wedged_mode,
> -		 "Module's default policy for the wedged mode - 0=never, 1=upon-critical-errors[default], 2=upon-any-hang");
> +		 "Module's default policy for the wedged mode (0=never, 1=upon-critical-errors, 2=upon-any-hang "
> +		 "[default=" __stringify(DEFAULT_WEDGED_MODE) "])");
>   
>   static int xe_check_nomodeset(void)
>   {
>