From 759d4fff3d2d70d6b689a9f1f7eb4488df337fbd Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Tue, 18 Jan 2022 11:23:42 +0200 Subject: [PATCH] drm/i915: Fix plane relative_data_rate calculation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We are currently computing the relative data rates as src_size * scale_factor where scale_factor is src_size / dst_size. Thus relative data rate is src_size * src_size / dst_size, which is just utter nonsense. What we really seem to want is just a reasonable estimate on how much data will be fetched which is just src_size. So let's do that instead. Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20220118092354.11631-4-ville.syrjala@linux.intel.com Reviewed-by: Stanislav Lisovskiy --- drivers/gpu/drm/i915/intel_pm.c | 63 ++------------------------------- 1 file changed, 2 insertions(+), 61 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 9a0a88529551..a540f6668aae 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -4356,55 +4356,6 @@ void skl_pipe_ddb_get_hw_state(struct intel_crtc *crtc, intel_display_power_put(dev_priv, power_domain, wakeref); } -/* - * 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 uint_fixed_16_16_t -skl_plane_downscale_amount(const struct intel_crtc_state *crtc_state, - const struct intel_plane_state *plane_state) -{ - struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev); - u32 src_w, src_h, dst_w, dst_h; - uint_fixed_16_16_t fp_w_ratio, fp_h_ratio; - uint_fixed_16_16_t downscale_h, downscale_w; - - if (drm_WARN_ON(&dev_priv->drm, - !intel_wm_plane_visible(crtc_state, plane_state))) - return u32_to_fixed16(0); - - /* - * Src coordinates are already rotated by 270 degrees for - * the 90/270 degree plane rotation cases (to match the - * GTT mapping), hence no need to account for rotation here. - * - * n.b., src is 16.16 fixed point, dst is whole integer. - */ - src_w = drm_rect_width(&plane_state->uapi.src) >> 16; - src_h = drm_rect_height(&plane_state->uapi.src) >> 16; - dst_w = drm_rect_width(&plane_state->uapi.dst); - dst_h = drm_rect_height(&plane_state->uapi.dst); - - fp_w_ratio = div_fixed16(src_w, dst_w); - fp_h_ratio = div_fixed16(src_h, dst_h); - downscale_w = max_fixed16(fp_w_ratio, u32_to_fixed16(1)); - downscale_h = max_fixed16(fp_h_ratio, u32_to_fixed16(1)); - - return mul_fixed16(downscale_w, downscale_h); -} - struct dbuf_slice_conf_entry { u8 active_pipes; u8 dbuf_mask[I915_MAX_PIPES]; @@ -4960,10 +4911,7 @@ skl_plane_relative_data_rate(const struct intel_crtc_state *crtc_state, { struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane); const struct drm_framebuffer *fb = plane_state->hw.fb; - u32 data_rate; - u32 width = 0, height = 0; - uint_fixed_16_16_t down_scale_amount; - u64 rate; + int width, height; if (!plane_state->uapi.visible) return 0; @@ -4997,14 +4945,7 @@ skl_plane_relative_data_rate(const struct intel_crtc_state *crtc_state, height /= 2; } - data_rate = width * height; - - down_scale_amount = skl_plane_downscale_amount(crtc_state, plane_state); - - rate = mul_round_up_u32_fixed16(data_rate, down_scale_amount); - - rate *= fb->format->cpp[color_plane]; - return rate; + return width * height * fb->format->cpp[color_plane]; } static u64