Re: [PATCH v4 19/33] drm/xe/uapi: Add DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR

["Ghimiray, Himal Prasad" <himal.prasad.ghimiray@intel.com>]

On 30-01-2025 01:21, Matthew Brost wrote:
> Add the DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR device query flag,
> which indicates whether the device supports CPU address mirroring. The
> intent is for UMDs to use this query to determine if a VM can be set up
> with CPU address mirroring. This flag is implemented by checking if the
> device supports GPU faults.
> 
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> ---
>   drivers/gpu/drm/xe/xe_query.c | 5 ++++-
>   include/uapi/drm/xe_drm.h     | 3 +++
>   2 files changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_query.c b/drivers/gpu/drm/xe/xe_query.c
> index c059639613f7..40f56eaf98fa 100644
> --- a/drivers/gpu/drm/xe/xe_query.c
> +++ b/drivers/gpu/drm/xe/xe_query.c
> @@ -333,8 +333,11 @@ static int query_config(struct xe_device *xe, struct drm_xe_device_query *query)
>   	config->info[DRM_XE_QUERY_CONFIG_REV_AND_DEVICE_ID] =
>   		xe->info.devid | (xe->info.revid << 16);
>   	if (xe_device_get_root_tile(xe)->mem.vram.usable_size)
> -		config->info[DRM_XE_QUERY_CONFIG_FLAGS] =
> +		config->info[DRM_XE_QUERY_CONFIG_FLAGS] |=
>   			DRM_XE_QUERY_CONFIG_FLAG_HAS_VRAM;
> +	if (xe->info.has_usm)
> +		config->info[DRM_XE_QUERY_CONFIG_FLAGS] |=
> +			DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR;
>   	config->info[DRM_XE_QUERY_CONFIG_MIN_ALIGNMENT] =
>   		xe->info.vram_flags & XE_VRAM_FLAGS_NEED64K ? SZ_64K : SZ_4K;
>   	config->info[DRM_XE_QUERY_CONFIG_VA_BITS] = xe->info.va_bits;
> diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
> index b86dc1b4c2fe..37e54ca6ffe9 100644
> --- a/include/uapi/drm/xe_drm.h
> +++ b/include/uapi/drm/xe_drm.h
> @@ -393,6 +393,8 @@ struct drm_xe_query_mem_regions {
>    *
>    *    - %DRM_XE_QUERY_CONFIG_FLAG_HAS_VRAM - Flag is set if the device
>    *      has usable VRAM
> + *    - %DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR - Flag is set if the
> + *      device has CPU address mirroring support
>    *  - %DRM_XE_QUERY_CONFIG_MIN_ALIGNMENT - Minimal memory alignment
>    *    required by this device, typically SZ_4K or SZ_64K
>    *  - %DRM_XE_QUERY_CONFIG_VA_BITS - Maximum bits of a virtual address
> @@ -409,6 +411,7 @@ struct drm_xe_query_config {
>   #define DRM_XE_QUERY_CONFIG_REV_AND_DEVICE_ID	0
>   #define DRM_XE_QUERY_CONFIG_FLAGS			1
>   	#define DRM_XE_QUERY_CONFIG_FLAG_HAS_VRAM	(1 << 0)
> +	#define DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR	(1 << 1)

LGTM
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>

>   #define DRM_XE_QUERY_CONFIG_MIN_ALIGNMENT		2
>   #define DRM_XE_QUERY_CONFIG_VA_BITS			3
>   #define DRM_XE_QUERY_CONFIG_MAX_EXEC_QUEUE_PRIORITY	4