[Intel-gfx] [PATCH v3 14/16] drm/i915/pxp: Add plane decryption support

[Daniele Ceraolo Spurio]

From: Anshuman Gupta <anshuman.gupta at intel.com>

Add support to enable/disable PLANE_SURF Decryption Request bit.
It requires only to enable plane decryption support when following
condition met.
1. PXP session is enabled.
2. Buffer object is protected.

v2:
- Used gen fb obj user_flags instead gem_object_metadata. [Krishna]

v3:
- intel_pxp_gem_object_status() API changes.

v4: use intel_pxp_is_active (Daniele)
v5: rebase and use the new protected object status checker (Daniele)

Cc: Bommu Krishnaiah <krishnaiah.bommu at intel.com>
Cc: Huang Sean Z <sean.z.huang at intel.com>
Cc: Gaurav Kumar <kumar.gaurav at intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
---
 drivers/gpu/drm/i915/display/skl_universal_plane.c | 14 +++++++++++---
 drivers/gpu/drm/i915/i915_reg.h                    |  1 +
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
index c6d7b6c054b5..b21bfb5be876 100644
--- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
+++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
@@ -16,6 +16,7 @@
 #include "intel_sprite.h"
 #include "skl_scaler.h"
 #include "skl_universal_plane.h"
+#include "pxp/intel_pxp.h"
 
 static const u32 skl_plane_formats[] = {
 	DRM_FORMAT_C8,
@@ -971,7 +972,7 @@ skl_program_plane(struct intel_plane *plane,
 	u8 alpha = plane_state->hw.alpha >> 8;
 	u32 plane_color_ctl = 0, aux_dist = 0;
 	unsigned long irqflags;
-	u32 keymsk, keymax;
+	u32 keymsk, keymax, plane_surf;
 	u32 plane_ctl = plane_state->ctl;
 
 	plane_ctl |= skl_plane_ctl_crtc(crtc_state);
@@ -1051,8 +1052,15 @@ skl_program_plane(struct intel_plane *plane,
 	 * the control register just before the surface register.
 	 */
 	intel_de_write_fw(dev_priv, PLANE_CTL(pipe, plane_id), plane_ctl);
-	intel_de_write_fw(dev_priv, PLANE_SURF(pipe, plane_id),
-			  intel_plane_ggtt_offset(plane_state) + surf_addr);
+	plane_surf = intel_plane_ggtt_offset(plane_state) + surf_addr;
+
+	if (intel_pxp_is_active(&dev_priv->gt.pxp) &&
+	    i915_gem_object_has_valid_protection(intel_fb_obj(fb)))
+		plane_surf |= PLANE_SURF_DECRYPTION_ENABLED;
+	else
+		plane_surf &= ~PLANE_SURF_DECRYPTION_ENABLED;
+
+	intel_de_write_fw(dev_priv, PLANE_SURF(pipe, plane_id), plane_surf);
 
 	if (plane_state->scaler_id >= 0)
 		skl_program_plane_scaler(plane, crtc_state, plane_state);
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 1fe42f4a4e4b..a0313d718905 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7234,6 +7234,7 @@ enum {
 #define _PLANE_SURF_3(pipe)	_PIPE(pipe, _PLANE_SURF_3_A, _PLANE_SURF_3_B)
 #define PLANE_SURF(pipe, plane)	\
 	_MMIO_PLANE(plane, _PLANE_SURF_1(pipe), _PLANE_SURF_2(pipe))
+#define   PLANE_SURF_DECRYPTION_ENABLED		REG_BIT(2)
 
 #define _PLANE_OFFSET_1_B			0x711a4
 #define _PLANE_OFFSET_2_B			0x712a4
-- 
2.29.2