[Intel-gfx] [PATCH v6 13/15] drm/i915/pxp: Add plane decryption support

Anshuman Gupta
2021-08-12T08:34:37Z

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)

v6: used plane state for plane_decryption to handle async flip
as suggested by Ville.

v7: check pxp session while plane decrypt state computation. [Ville]
removed pointless code. [Ville]

v8 (Daniele): update PXP check

v9: move decrypt check after icl_check_nv12_planes() when overlays
have fb set (Juston)

Cc: Bommu Krishnaiah <krishnaiah.bommu@intel.com>
Cc: Huang Sean Z <sean.z.huang@intel.com>
Cc: Gaurav Kumar <kumar.gaurav@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Juston Li <juston.li@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
---
drivers/gpu/drm/i915/display/intel_display.c | 27 +++++++++++++++++++
.../drm/i915/display/intel_display_types.h | 3 +++
.../drm/i915/display/skl_universal_plane.c | 15 ++++++++---
drivers/gpu/drm/i915/i915_reg.h | 1 +
4 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index b25c596f6f7e..accdd6614681 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -70,6 +70,8 @@
#include "gt/intel_rps.h"
#include "gt/gen8_ppgtt.h"

+#include "pxp/intel_pxp.h"
+
#include "g4x_dp.h"
#include "g4x_hdmi.h"
#include "i915_drv.h"
@@ -9610,13 +9612,24 @@ static int intel_bigjoiner_add_affected_planes(struct intel_atomic_state *state)
return 0;
}

+static int bo_has_valid_encryption(const struct drm_i915_gem_object *obj)
+{
+ struct drm_i915_private *i915 = to_i915(obj->base.dev);
+
+ return i915_gem_object_has_valid_protection(obj) &&
+ intel_pxp_is_active(&i915->gt.pxp);
+}
+
static int intel_atomic_check_planes(struct intel_atomic_state *state)
{
struct drm_i915_private *dev_priv = to_i915(state->base.dev);
struct intel_crtc_state *old_crtc_state, *new_crtc_state;
struct intel_plane_state *plane_state;
struct intel_plane *plane;
+ struct intel_plane_state *new_plane_state;
+ struct intel_plane_state *old_plane_state;
struct intel_crtc *crtc;
+ const struct drm_framebuffer *fb;
int i, ret;

ret = icl_add_linked_planes(state);
@@ -9664,6 +9677,16 @@ static int intel_atomic_check_planes(struct intel_atomic_state *state)
return ret;
}

+ for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
+ new_plane_state = intel_atomic_get_new_plane_state(state, plane);
+ old_plane_state = intel_atomic_get_old_plane_state(state, plane);
+ fb = new_plane_state->hw.fb;
+ if (fb)
+ new_plane_state->decrypt = bo_has_valid_encryption(intel_fb_obj(fb));
+ else
+ new_plane_state->decrypt = old_plane_state->decrypt;
+ }
+
return 0;
}

@@ -9950,6 +9973,10 @@ static int intel_atomic_check_async(struct intel_atomic_state *state)
drm_dbg_kms(&i915->drm, "Color range cannot be changed in async flip\n");
return -EINVAL;
}
+
+ /* plane decryption is allow to change only in synchronous flips */
+ if (old_plane_state->decrypt != new_plane_state->decrypt)
+ return -EINVAL;
}

return 0;
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 6beeeeba1bed..53b5db3c6228 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -629,6 +629,9 @@ struct intel_plane_state {

struct intel_fb_view view;

+ /* Plane pxp decryption state */
+ bool decrypt;
+
/* plane control register */
u32 ctl;

diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
index 724e7b04f3b6..55e3f093b951 100644
--- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
+++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
@@ -18,6 +18,7 @@
#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,
@@ -1024,7 +1025,7 @@ 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);
@@ -1113,8 +1114,16 @@ 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;
+
+ /*
+ * FIXME: pxp session invalidation can hit any time even at time of commit
+ * or after the commit, display content will be garbage.
+ */
+ if (plane_state->decrypt)
+ plane_surf |= PLANE_SURF_DECRYPT;
+
+ intel_de_write_fw(dev_priv, PLANE_SURF(pipe, plane_id), plane_surf);

spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
}
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index f76eaed8e855..57f22f54d9f7 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7347,6 +7347,7 @@ 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_DECRYPT REG_BIT(2)

#define _PLANE_OFFSET_1_B 0x711a4
#define _PLANE_OFFSET_2_B 0x712a4
--
2.26.2