From: "Kumar, Mahesh" <mahesh1.kumar@xxxxxxxxx>
Don't use pipe pixel rate for plane pixel rate. Calculate plane pixel according
to formula
adjusted plane_pixel_rate = adjusted pipe_pixel_rate * downscale ammount
downscale amount = max[1, src_h/dst_h] * max[1, src_w/dst_w]
if 90/270 rotation use rotated width & height
v2: use intel_plane_state->visible instead of (fb == NULL) as per Matt's
comment.
v3 (by Matt):
- Keep downscale amount in 16.16 fixed point rather than converting to
decimal fixed point.
- Store adjusted plane pixel rate in plane state instead of the plane
parameters structure that we no longer use.
v4 (by Matt):
- Significant rebasing onto latest atomic watermark work
- Don't bother storing plane pixel rate in state; just calculate it
right before the calls that make use of it.
- Fix downscale calculations to actually use width values when
computing downscale_w rather than copy/pasted height values.
Cc: matthew.d.roper@xxxxxxxxx
Signed-off-by: Kumar, Mahesh <mahesh1.kumar@xxxxxxxxx>
Signed-off-by: Matt Roper <matthew.d.roper@xxxxxxxxx>
---
drivers/gpu/drm/i915/intel_pm.c | 73 +++++++++++++++++++++++++++++++++++++++--
1 file changed, 70 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index d7165b5..5bd885b 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -26,6 +26,7 @@
*/
#include <linux/cpufreq.h>
+#include <drm/drm_plane_helper.h>
#include "i915_drv.h"
#include "intel_drv.h"
#include "../../../platform/x86/intel_ips.h"
@@ -2945,6 +2946,46 @@ void skl_ddb_get_hw_state(struct drm_i915_private *dev_priv,
}
}
+/*
+ * Determines the downscale amount of a plane for the purposes of watermark calculations.
+ * The bspec defines downscale amount as:
+ *
+ * """
+ * Horizontal down scale amount = maximum[1, Horizontal source size /
+ * Horizontal destination size]
+ * Vertical down scale amount = maximum[1, Vertical source size /
+ * Vertical destination size]
+ * Total down scale amount = Horizontal down scale amount *
+ * Vertical down scale amount
+ * """
+ *
+ * Return value is provided in 16.16 fixed point form to retain fractional part.
+ * Caller should take care of dividing & rounding off the value.
+ */
+static uint32_t
+skl_plane_downscale_amount(const struct intel_plane_state *pstate)
+{
+ uint32_t downscale_h, downscale_w;
+ uint32_t src_w, src_h, dst_w, dst_h;
+
+ if (WARN_ON(!pstate->visible))
+ return DRM_PLANE_HELPER_NO_SCALING;
+
+ /* n.b., src is 16.16 fixed point, dst is whole integer */
+ src_w = drm_rect_width(&pstate->src);
+ src_h = drm_rect_height(&pstate->src);
+ dst_w = drm_rect_width(&pstate->dst);
+ dst_h = drm_rect_height(&pstate->dst);
+ if (intel_rotation_90_or_270(pstate->base.rotation))
+ swap(dst_w, dst_h);
+
+ downscale_h = max(src_h / dst_h, (uint32_t)DRM_PLANE_HELPER_NO_SCALING);
+ downscale_w = max(src_w / dst_w, (uint32_t)DRM_PLANE_HELPER_NO_SCALING);
+
+ /* Provide result in 16.16 fixed point */
+ return (uint64_t)downscale_w * downscale_h >> 16;
+}
+
static unsigned int
skl_plane_relative_data_rate(const struct intel_crtc_state *cstate,
const struct drm_plane_state *pstate,
@@ -3273,6 +3314,30 @@ static uint32_t skl_wm_method2(uint32_t pixel_rate, uint32_t pipe_htotal,
return ret;
}
+static uint32_t skl_adjusted_plane_pixel_rate(const struct intel_crtc_state *cstate,
+ struct intel_plane_state *pstate)
+{
+ uint64_t adjusted_pixel_rate;
+ uint64_t downscale_amount;
+ uint64_t pixel_rate;
+
+ /* Shouldn't reach here on disabled planes... */
+ if (WARN_ON(!pstate->visible))
+ return 0;
+
+ /*
+ * Adjusted plane pixel rate is just the pipe's adjusted pixel rate
+ * with additional adjustments for plane-specific scaling.
+ */
+ adjusted_pixel_rate = skl_pipe_pixel_rate(cstate);
+ downscale_amount = skl_plane_downscale_amount(pstate);
+
+ pixel_rate = adjusted_pixel_rate * downscale_amount >> 16;
+ WARN_ON(pixel_rate != clamp_t(uint32_t, pixel_rate, 0, ~0));
+
+ return pixel_rate;
+}
+
static int skl_compute_plane_wm(const struct drm_i915_private *dev_priv,
struct intel_crtc_state *cstate,
struct intel_plane_state *intel_pstate,
@@ -3291,6 +3356,7 @@ static int skl_compute_plane_wm(const struct drm_i915_private *dev_priv,
uint32_t selected_result;
uint8_t cpp;
uint32_t width = 0, height = 0;
+ uint32_t plane_pixel_rate;
if (latency == 0 || !cstate->base.active || !intel_pstate->visible) {
*enabled = false;
@@ -3304,9 +3370,10 @@ static int skl_compute_plane_wm(const struct drm_i915_private *dev_priv,
swap(width, height);
cpp = drm_format_plane_cpp(fb->pixel_format, 0);
- method1 = skl_wm_method1(skl_pipe_pixel_rate(cstate),
- cpp, latency);
- method2 = skl_wm_method2(skl_pipe_pixel_rate(cstate),
+ plane_pixel_rate = skl_adjusted_plane_pixel_rate(cstate, intel_pstate);
+
+ method1 = skl_wm_method1(plane_pixel_rate, cpp, latency);
+ method2 = skl_wm_method2(plane_pixel_rate,
cstate->base.adjusted_mode.crtc_htotal,
width,
cpp,
