drm/xe/pxp/uapi: Add userspace and LRC support for PXP-using queues

Userspace is required to mark a queue as using PXP to guarantee that the
PXP instructions will work. In addition to managing the PXP sessions,
when a PXP queue is created the driver will set the relevant bits in
its context control register.

On submission of a valid PXP queue, the driver will validate all
encrypted objects mapped to the VM to ensured they were encrypted with
the current key.

v2: Remove pxp_types include outside of PXP code (Jani), better comments
and code cleanup (John)

v3: split the internal PXP management to a separate patch for ease of
review. re-order ioctl checks to always return -EINVAL if parameters are
invalid, rebase on msix changes.

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250129174140.948829-9-daniele.ceraolospurio@intel.com

1 files changed, 39 insertions, 1 deletions

diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
index e2160330ad01..9d53834c4c0a 100644
--- a/include/uapi/drm/xe_drm.h
+++ b/include/uapi/drm/xe_drm.h
@@ -1114,6 +1114,24 @@ struct drm_xe_vm_bind {
 /**
  * struct drm_xe_exec_queue_create - Input of &DRM_IOCTL_XE_EXEC_QUEUE_CREATE
  *
+ * This ioctl supports setting the following properties via the
+ * %DRM_XE_EXEC_QUEUE_EXTENSION_SET_PROPERTY extension, which uses the
+ * generic @drm_xe_ext_set_property struct:
+ *
+ *  - %DRM_XE_EXEC_QUEUE_SET_PROPERTY_PRIORITY - set the queue priority.
+ *    CAP_SYS_NICE is required to set a value above normal.
+ *  - %DRM_XE_EXEC_QUEUE_SET_PROPERTY_TIMESLICE - set the queue timeslice
+ *    duration in microseconds.
+ *  - %DRM_XE_EXEC_QUEUE_SET_PROPERTY_PXP_TYPE - set the type of PXP session
+ *    this queue will be used with. Valid values are listed in enum
+ *    drm_xe_pxp_session_type. %DRM_XE_PXP_TYPE_NONE is the default behavior, so
+ *    there is no need to explicitly set that. When a queue of type
+ *    %DRM_XE_PXP_TYPE_HWDRM is created, the PXP default HWDRM session
+ *    (%XE_PXP_HWDRM_DEFAULT_SESSION) will be started, if isn't already running.
+ *    Given that going into a power-saving state kills PXP HWDRM sessions,
+ *    runtime PM will be blocked while queues of this type are alive.
+ *    All PXP queues will be killed if a PXP invalidation event occurs.
+ *
  * The example below shows how to use @drm_xe_exec_queue_create to create
  * a simple exec_queue (no parallel submission) of class
  * &DRM_XE_ENGINE_CLASS_RENDER.
@@ -1137,7 +1155,7 @@ struct drm_xe_exec_queue_create {
 #define DRM_XE_EXEC_QUEUE_EXTENSION_SET_PROPERTY		0
 #define   DRM_XE_EXEC_QUEUE_SET_PROPERTY_PRIORITY		0
 #define   DRM_XE_EXEC_QUEUE_SET_PROPERTY_TIMESLICE		1
-
+#define   DRM_XE_EXEC_QUEUE_SET_PROPERTY_PXP_TYPE		2
 	/** @extensions: Pointer to the first extension struct, if any */
 	__u64 extensions;
 
@@ -1756,6 +1774,26 @@ struct drm_xe_oa_stream_info {
 	__u64 reserved[3];
 };
 
+/**
+ * enum drm_xe_pxp_session_type - Supported PXP session types.
+ *
+ * We currently only support HWDRM sessions, which are used for protected
+ * content that ends up being displayed, but the HW supports multiple types, so
+ * we might extend support in the future.
+ */
+enum drm_xe_pxp_session_type {
+	/** @DRM_XE_PXP_TYPE_NONE: PXP not used */
+	DRM_XE_PXP_TYPE_NONE = 0,
+	/**
+	 * @DRM_XE_PXP_TYPE_HWDRM: HWDRM sessions are used for content that ends
+	 * up on the display.
+	 */
+	DRM_XE_PXP_TYPE_HWDRM = 1,
+};
+
+/* ID of the protected content session managed by Xe when PXP is active */
+#define DRM_XE_PXP_HWDRM_DEFAULT_SESSION 0xf
+
 #if defined(__cplusplus)
 }
 #endif