[PATCH 10/21 v3] drm/i915: Helper function to detach a scaler from a plane or crtc

Chandra Konduru
2015-03-25T23:22:37Z

This function is called from commit path of a plane or crtc.
It programs scaler registers to detach (aka. unbinds) scaler
from requested plane or crtc if it isn't in use. It also resets
scaler_id in crtc/plane state.

v2:
-improved a log message (me)

v3:
-improved commentary (Matt)
-added a case where scaler id needs to be reset (me)

Signed-off-by: Chandra Konduru <chandra.konduru@intel.com>
---
drivers/gpu/drm/i915/intel_display.c | 57 ++++++++++++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_drv.h | 1 +
2 files changed, 58 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 5c365f3..8290c7d 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2836,6 +2836,63 @@ u32 intel_fb_stride_alignment(struct drm_device *dev, uint64_t fb_modifier,
}
}

+/*
+ * This function detaches (aka. unbinds) a scaler from plane or crtc
+ * if scaler is not in use.
+ * It resets scaler_id in plane or crtc
+ * To request detach a scaler from crtc, call plane as NULL
+ */
+void skl_detach_scaler(struct drm_crtc *crtc, struct drm_plane *plane)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_crtc_state *crtc_state;
+ struct intel_crtc *intel_crtc;
+ struct intel_plane *intel_plane;
+ struct intel_plane_state *plane_state;
+ int *scaler_id;
+ int idx;
+
+ intel_crtc = to_intel_crtc(crtc);
+ intel_plane = plane ? to_intel_plane(plane) : NULL;
+ crtc_state = intel_crtc->config;
+ plane_state = plane ? to_intel_plane_state(plane->state) : NULL;
+
+ idx = plane ? drm_plane_index(plane) : SKL_CRTC_INDEX;
+ scaler_id = plane ? (plane_state ? &plane_state->scaler_id : NULL) :
+ &crtc_state->scaler_state.scaler_id;
+
+ if (!scaler_id || (scaler_id && *scaler_id < 0))
+ return;
+
+ /*
+ * staged scaler state can trigger below:
+ *
+ * 1) scaler is freed and not attached to any other user. In this case,
+ * reg programming needed to update hw. And reset scaler_id to -1
+ * to indicate scaler isn't used. Once done, both sw and hw states
+ * are in sync.
+ * 2) scaler is freed and attached to other user. In this case, registers
+ * shouldn't be touched here because scaler is used by new owner.
+ * Just reset scaler_id to -1.
+ * 3) scaler is with same user as before. In this case, registers
+ * shouldn't be touched. No action needed.
+ */
+ if (!crtc_state->scaler_state.scalers[*scaler_id].in_use) {
+ I915_WRITE(SKL_PS_CTRL(intel_crtc->pipe, (*scaler_id)), 0);
+ I915_WRITE(SKL_PS_WIN_POS(intel_crtc->pipe, (*scaler_id)), 0);
+ I915_WRITE(SKL_PS_WIN_SZ(intel_crtc->pipe, (*scaler_id)), 0);
+ DRM_DEBUG_KMS("Detached and disabled scaler id %u.%u from %s:%d\n",
+ intel_crtc->pipe, *scaler_id, plane ? "PLANE" : "CRTC",
+ plane ? plane->base.id : crtc->base.id);
+ *scaler_id = -1;
+ }
+
+ if (!(crtc_state->scaler_state.scaler_users & (1 << idx))) {
+ *scaler_id = -1;
+ }
+}
+
static void skylake_update_primary_plane(struct drm_crtc *crtc,
struct drm_framebuffer *fb,
int x, int y)
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index a9d787d..f25d14d 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1141,6 +1141,7 @@ void intel_modeset_preclose(struct drm_device *dev, struct drm_file *file);
int skl_update_scaler_users(struct intel_crtc *intel_crtc,
struct intel_crtc_state *crtc_state, struct intel_plane *intel_plane,
struct intel_plane_state *plane_state, int force_detach);
+void skl_detach_scaler(struct drm_crtc *crtc, struct drm_plane *plane);

/* intel_dp.c */
void intel_dp_init(struct drm_device *dev, int output_reg, enum port port);
--
1.7.9.5