From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
In order to handle the DEwake tricks without involving
the CPU we need a mechanism by which one DSB can start
another one. Add a basic function to do so. We'll extend
it later with additional code to actually deal with
DEwake.
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_dsb.c | 42 ++++++++++++++++++++++++
drivers/gpu/drm/i915/display/intel_dsb.h | 3 ++
2 files changed, 45 insertions(+)
diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c
index 092cf082ac39..4c0519c41f16 100644
--- a/drivers/gpu/drm/i915/display/intel_dsb.c
+++ b/drivers/gpu/drm/i915/display/intel_dsb.c
@@ -502,6 +502,48 @@ static u32 dsb_error_int_en(struct intel_display *display)
return errors;
}
+static void _intel_dsb_chain(struct intel_atomic_state *state,
+ struct intel_dsb *dsb,
+ struct intel_dsb *chained_dsb,
+ u32 ctrl)
+{
+ struct intel_display *display = to_intel_display(state->base.dev);
+ struct intel_crtc *crtc = dsb->crtc;
+ enum pipe pipe = crtc->pipe;
+ u32 tail;
+
+ if (drm_WARN_ON(display->drm, dsb->id == chained_dsb->id))
+ return;
+
+ tail = chained_dsb->free_pos * 4;
+ if (drm_WARN_ON(display->drm, !IS_ALIGNED(tail, CACHELINE_BYTES)))
+ return;
+
+ intel_dsb_reg_write(dsb, DSB_CTRL(pipe, chained_dsb->id),
+ ctrl | DSB_ENABLE);
+
+ intel_dsb_reg_write(dsb, DSB_CHICKEN(pipe, chained_dsb->id),
+ dsb_chicken(state, crtc));
+
+ intel_dsb_reg_write(dsb, DSB_INTERRUPT(pipe, chained_dsb->id),
+ dsb_error_int_status(display) | DSB_PROG_INT_STATUS |
+ dsb_error_int_en(display));
+
+ intel_dsb_reg_write(dsb, DSB_HEAD(pipe, chained_dsb->id),
+ intel_dsb_buffer_ggtt_offset(&chained_dsb->dsb_buf));
+
+ intel_dsb_reg_write(dsb, DSB_TAIL(pipe, chained_dsb->id),
+ intel_dsb_buffer_ggtt_offset(&chained_dsb->dsb_buf) + tail);
+}
+
+void intel_dsb_chain(struct intel_atomic_state *state,
+ struct intel_dsb *dsb,
+ struct intel_dsb *chained_dsb)
+{
+ _intel_dsb_chain(state, dsb, chained_dsb,
+ 0);
+}
+
static void _intel_dsb_commit(struct intel_dsb *dsb, u32 ctrl,
int hw_dewake_scanline)
{
diff --git a/drivers/gpu/drm/i915/display/intel_dsb.h b/drivers/gpu/drm/i915/display/intel_dsb.h
index d0737cefb393..e59fd7da0fc0 100644
--- a/drivers/gpu/drm/i915/display/intel_dsb.h
+++ b/drivers/gpu/drm/i915/display/intel_dsb.h
@@ -45,6 +45,9 @@ void intel_dsb_wait_scanline_in(struct intel_atomic_state *state,
void intel_dsb_wait_scanline_out(struct intel_atomic_state *state,
struct intel_dsb *dsb,
int lower, int upper);
+void intel_dsb_chain(struct intel_atomic_state *state,
+ struct intel_dsb *dsb,
+ struct intel_dsb *chained_dsb);
void intel_dsb_commit(struct intel_dsb *dsb,
bool wait_for_vblank);
--
2.44.2
