On Tue, Feb 25, 2020 at 12:35:45PM +0530, Pankaj Bharadiya wrote:
Integer scaling (IS) is a nearest-neighbor upscaling technique that simply scales up the existing pixels by an integer (i.e., whole number) multiplier.Nearest-neighbor (NN) interpolation works by filling in the missing color values in the upscaled image with that of the coordinate-mapped nearest source pixel value.
Both IS and NN preserve the clarity of the original image. Integer scaling is particularly useful for pixel art games that rely on sharp, blocky images to deliver their distinctive look.
Program the scaler filter coefficients to enable the NN filter if scaling filter property is set to DRM_SCALING_FILTER_NEAREST_NEIGHBOR and enable integer scaling.
Bspec: 49247
Signed-off-by: Pankaj Bharadiya pankaj.laxminarayan.bharadiya@intel.com Signed-off-by: Ankit Nautiyal ankit.k.nautiyal@intel.com
drivers/gpu/drm/i915/display/intel_display.c | 83 +++++++++++++++++++- drivers/gpu/drm/i915/display/intel_display.h | 2 + drivers/gpu/drm/i915/display/intel_sprite.c | 20 +++-- 3 files changed, 97 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c index b5903ef3c5a0..6d5f59203258 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -6237,6 +6237,73 @@ void skl_scaler_disable(const struct intel_crtc_state *old_crtc_state) skl_detach_scaler(crtc, i); }
+/**
- Theory behind setting nearest-neighbor integer scaling:
- 17 phase of 7 taps requires 119 coefficients in 60 dwords per set.
- The letter represents the filter tap (D is the center tap) and the number
- represents the coefficient set for a phase (0-16).
+------------+------------------------+------------------------+
|Index value | Data value coeffient 1 | Data value coeffient 2 |
+------------+------------------------+------------------------+
| 00h | B0 | A0 |
+------------+------------------------+------------------------+
| 01h | D0 | C0 |
+------------+------------------------+------------------------+
| 02h | F0 | E0 |
+------------+------------------------+------------------------+
| 03h | A1 | G0 |
+------------+------------------------+------------------------+
| 04h | C1 | B1 |
+------------+------------------------+------------------------+
| ... | ... | ... |
+------------+------------------------+------------------------+
| 38h | B16 | A16 |
+------------+------------------------+------------------------+
| 39h | D16 | C16 |
+------------+------------------------+------------------------+
| 3Ah | F16 | C16 |
+------------+------------------------+------------------------+
| 3Bh | Reserved | G16 |
+------------+------------------------+------------------------+
- To enable nearest-neighbor scaling: program scaler coefficents with
- the center tap (Dxx) values set to 1 and all other values set to 0 as per
- SCALER_COEFFICIENT_FORMAT
- */
+void skl_setup_nearest_neighbor_filter(struct drm_i915_private *dev_priv,
enum pipe pipe, int scaler_id)
skl_scaler_...
+{
- int coeff = 0;
- int phase = 0;
- int tap;
- int val = 0;
Needlessly wide scope for most of these.
- /*enable the index auto increment.*/
- intel_de_write_fw(dev_priv, SKL_PS_COEF_INDEX_SET0(pipe, scaler_id),
_PS_COEE_INDEX_AUTO_INC);- for (phase = 0; phase < 17; phase++) {
for (tap = 0; tap < 7; tap++) {coeff++;
Can be part of the % check.
if (tap == 3)val = (phase % 2) ? (0x800) : (0x800 << 16);
Parens overload.
if (coeff % 2 == 0) {intel_de_write_fw(dev_priv, SKL_PS_COEF_DATA_SET0(pipe, scaler_id), val);val = 0;
Can drop this val=0 if you move the variable into tight scope and initialize there.
I was trying to think of a bit more generic way to do this, but couldn't really think of anything apart from pre-filling the entire coefficient set and the programming blindly. And that seems a bit wasteful if we only care about nearest neighbour.
}}- }
- intel_de_write_fw(dev_priv, SKL_PS_COEF_DATA_SET0(pipe, scaler_id), 0);
+}
static void skl_pfit_enable(const struct intel_crtc_state *crtc_state) { struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc); @@ -6260,9 +6327,23 @@ static void skl_pfit_enable(const struct intel_crtc_state *crtc_state) pfit_w = (crtc_state->pch_pfit.size >> 16) & 0xFFFF; pfit_h = crtc_state->pch_pfit.size & 0xFFFF;
id = scaler_state->scaler_id;- if (state->scaling_filter == DRM_SCALING_FILTER_NEAREST_NEIGHBOR) { scaling_filter = PS_FILTER_PROGRAMMED;
skl_setup_nearest_neighbor_filter(dev_priv, pipe, id);
This should be sitting alongside the other register writes.
/* Make the scaling window size to integer multiple of* source.** TODO: Should userspace take desision to round* scaling window to integer multiple?
To give userspace actual control of the pfit window size we need the border props (or something along those lines). Step 1 is https://patchwork.freedesktop.org/series/68409/. There are further steps in my branch after that, but it's still missing the border props for eDP/LVDS/DSI since I was too lazy to think how they should interact with the existing scaling mode prop.
*/pfit_w = rounddown(pfit_w,(crtc_state->pipe_src_w << 16));pfit_h = rounddown(pfit_h,(crtc_state->pipe_src_h << 16));
This part should be dropped as Daniel mentioned.
hscale = (crtc_state->pipe_src_w << 16) / pfit_w;@@ -6271,8 +6352,6 @@ static void skl_pfit_enable(const struct intel_crtc_state *crtc_state) 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;spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
intel_de_write_fw(dev_priv, SKL_PS_CTRL(pipe, id),
I think we should also explicitly indicate here which cofficient set(s) we're going to use, even if using set0 does mean those bits will be 0.
diff --git a/drivers/gpu/drm/i915/display/intel_display.h b/drivers/gpu/drm/i915/display/intel_display.h index f92efbbec838..49f58d3c98fe 100644 --- a/drivers/gpu/drm/i915/display/intel_display.h +++ b/drivers/gpu/drm/i915/display/intel_display.h @@ -586,6 +586,8 @@ void intel_crtc_arm_fifo_underrun(struct intel_crtc *crtc, u16 skl_scaler_calc_phase(int sub, int scale, bool chroma_center); int skl_update_scaler_crtc(struct intel_crtc_state *crtc_state); void skl_scaler_disable(const struct intel_crtc_state *old_crtc_state); +void skl_setup_nearest_neighbor_filter(struct drm_i915_private *dev_priv,
enum pipe pipe, int scaler_id);void ilk_pfit_disable(const struct intel_crtc_state *old_crtc_state); u32 glk_plane_color_ctl(const struct intel_crtc_state *crtc_state, const struct intel_plane_state *plane_state); diff --git a/drivers/gpu/drm/i915/display/intel_sprite.c b/drivers/gpu/drm/i915/display/intel_sprite.c index fd7b31a21723..5bef5c031374 100644 --- a/drivers/gpu/drm/i915/display/intel_sprite.c +++ b/drivers/gpu/drm/i915/display/intel_sprite.c @@ -415,18 +415,26 @@ skl_program_scaler(struct intel_plane *plane, u16 y_vphase, uv_rgb_vphase; int hscale, vscale; const struct drm_plane_state *state = &plane_state->uapi;
u32 src_w = drm_rect_width(&plane_state->uapi.src) >> 16;
u32 src_h = drm_rect_height(&plane_state->uapi.src) >> 16; u32 scaling_filter = PS_FILTER_MEDIUM;
struct drm_rect dst;
if (state->scaling_filter == DRM_SCALING_FILTER_NEAREST_NEIGHBOR) { scaling_filter = PS_FILTER_PROGRAMMED;
skl_setup_nearest_neighbor_filter(dev_priv, pipe, scaler_id);/* Make the scaling window size to integer multiple of source* TODO: Should userspace take desision to round scaling window* to integer multiple?*/crtc_w = rounddown(crtc_w, src_w);crtc_h = rounddown(crtc_h, src_h);}
- hscale = drm_rect_calc_hscale(&plane_state->uapi.src,
&plane_state->uapi.dst,0, INT_MAX);- vscale = drm_rect_calc_vscale(&plane_state->uapi.src,
&plane_state->uapi.dst,0, INT_MAX);
- drm_rect_init(&dst, crtc_x, crtc_y, crtc_w, crtc_h);
Drop as well.
hscale = drm_rect_calc_hscale(&plane_state->uapi.src, &dst, 0, INT_MAX);
vscale = drm_rect_calc_vscale(&plane_state->uapi.src, &dst, 0, INT_MAX);
/* TODO: handle sub-pixel coordinates */ if (intel_format_info_is_yuv_semiplanar(fb->format, fb->modifier) &&
-- 2.23.0