From e7a278a329dd8aa2c70c564849f164cb5673689c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Mon, 29 Oct 2018 20:18:20 +0200 Subject: [PATCH] drm/i915: Account for scale factor when calculating initial phase MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit To get the initial phase correct we need to account for the scale factor as well. I forgot this initially and was mostly looking at heavily upscaled content where the minor difference between -0.5 and the proper initial phase was not readily apparent. And let's toss in a comment that tries to explain the formula a little bit. v2: The initial phase upper limit is 1.5, not 24.0! Cc: Maarten Lankhorst Fixes: 0a59952b24e2 ("drm/i915: Configure SKL+ scaler initial phase correctly") Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20181029181820.21956-1-ville.syrjala@linux.intel.com Tested-by: Juha-Pekka Heikkila Tested-by: Maarten Lankhorst #irc Reviewed-by: Maarten Lankhorst #irc --- drivers/gpu/drm/i915/intel_display.c | 45 ++++++++++++++++++++++++++-- drivers/gpu/drm/i915/intel_drv.h | 2 +- drivers/gpu/drm/i915/intel_sprite.c | 20 +++++++++---- 3 files changed, 57 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 940577f8c041..e73638fffe32 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -4777,8 +4777,31 @@ static void cpt_verify_modeset(struct drm_device *dev, int pipe) * chroma samples for both of the luma samples, and thus we don't * actually get the expected MPEG2 chroma siting convention :( * The same behaviour is observed on pre-SKL platforms as well. + * + * Theory behind the formula (note that we ignore sub-pixel + * source coordinates): + * s = source sample position + * d = destination sample position + * + * Downscaling 4:1: + * -0.5 + * | 0.0 + * | | 1.5 (initial phase) + * | | | + * v v v + * | s | s | s | s | + * | d | + * + * Upscaling 1:4: + * -0.5 + * | -0.375 (initial phase) + * | | 0.0 + * | | | + * v v v + * | s | + * | d | d | d | d | */ -u16 skl_scaler_calc_phase(int sub, bool chroma_cosited) +u16 skl_scaler_calc_phase(int sub, int scale, bool chroma_cosited) { int phase = -0x8000; u16 trip = 0; @@ -4786,6 +4809,15 @@ u16 skl_scaler_calc_phase(int sub, bool chroma_cosited) if (chroma_cosited) phase += (sub - 1) * 0x8000 / sub; + phase += scale / (2 * sub); + + /* + * Hardware initial phase limited to [-0.5:1.5]. + * Since the max hardware scale factor is 3.0, we + * should never actually excdeed 1.0 here. + */ + WARN_ON(phase < -0x8000 || phase > 0x18000); + if (phase < 0) phase = 0x10000 + phase; else @@ -4994,13 +5026,20 @@ static void skylake_pfit_enable(const struct intel_crtc_state *crtc_state) if (crtc_state->pch_pfit.enabled) { u16 uv_rgb_hphase, uv_rgb_vphase; + int pfit_w, pfit_h, hscale, vscale; int id; if (WARN_ON(crtc_state->scaler_state.scaler_id < 0)) return; - uv_rgb_hphase = skl_scaler_calc_phase(1, false); - uv_rgb_vphase = skl_scaler_calc_phase(1, false); + pfit_w = (crtc_state->pch_pfit.size >> 16) & 0xFFFF; + pfit_h = crtc_state->pch_pfit.size & 0xFFFF; + + hscale = (crtc_state->pipe_src_w << 16) / pfit_w; + vscale = (crtc_state->pipe_src_h << 16) / pfit_h; + + uv_rgb_hphase = skl_scaler_calc_phase(1, hscale, false); + uv_rgb_vphase = skl_scaler_calc_phase(1, vscale, false); id = scaler_state->scaler_id; I915_WRITE(SKL_PS_CTRL(pipe, id), PS_SCALER_EN | diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index cc7fab2b61f4..18b419f7f7fe 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1720,7 +1720,7 @@ void intel_mode_from_pipe_config(struct drm_display_mode *mode, void intel_crtc_arm_fifo_underrun(struct intel_crtc *crtc, struct intel_crtc_state *crtc_state); -u16 skl_scaler_calc_phase(int sub, bool chroma_center); +u16 skl_scaler_calc_phase(int sub, int scale, bool chroma_center); int skl_update_scaler_crtc(struct intel_crtc_state *crtc_state); int skl_max_scale(const struct intel_crtc_state *crtc_state, u32 pixel_format); diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c index a38270b6e6d4..5e0f7b575a50 100644 --- a/drivers/gpu/drm/i915/intel_sprite.c +++ b/drivers/gpu/drm/i915/intel_sprite.c @@ -326,23 +326,31 @@ skl_program_scaler(struct intel_plane *plane, uint32_t crtc_h = drm_rect_height(&plane_state->base.dst); u16 y_hphase, uv_rgb_hphase; u16 y_vphase, uv_rgb_vphase; + int hscale, vscale; + + hscale = drm_rect_calc_hscale(&plane_state->base.src, + &plane_state->base.dst, + 0, INT_MAX); + vscale = drm_rect_calc_vscale(&plane_state->base.src, + &plane_state->base.dst, + 0, INT_MAX); /* TODO: handle sub-pixel coordinates */ if (plane_state->base.fb->format->format == DRM_FORMAT_NV12 && !icl_is_hdr_plane(plane)) { - y_hphase = skl_scaler_calc_phase(1, false); - y_vphase = skl_scaler_calc_phase(1, false); + y_hphase = skl_scaler_calc_phase(1, hscale, false); + y_vphase = skl_scaler_calc_phase(1, vscale, false); /* MPEG2 chroma siting convention */ - uv_rgb_hphase = skl_scaler_calc_phase(2, true); - uv_rgb_vphase = skl_scaler_calc_phase(2, false); + uv_rgb_hphase = skl_scaler_calc_phase(2, hscale, true); + uv_rgb_vphase = skl_scaler_calc_phase(2, vscale, false); } else { /* not used */ y_hphase = 0; y_vphase = 0; - uv_rgb_hphase = skl_scaler_calc_phase(1, false); - uv_rgb_vphase = skl_scaler_calc_phase(1, false); + uv_rgb_hphase = skl_scaler_calc_phase(1, hscale, false); + uv_rgb_vphase = skl_scaler_calc_phase(1, vscale, false); } I915_WRITE_FW(SKL_PS_CTRL(pipe, scaler_id),