drm/i915/scaler: Compute scaling factors for pipe scaler

Compute scaling factors and scaler user for pipe scaler if
particular scaler user is pipe scaler.

--v2:
- Fix typos. [Ankit]
- Remove FIXME tag. [Ankit]
- Should be common hscale, vscale instead of local one to
avoid garbage overwritten.

--v3:
- Separate out max_scaling information. [Ankit]
- Use max_hscale and max_vscale info instead of INT_MAX. [Ankit]

--v4:
- Add Suggested changes reported by Dan Carpenter.

Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250121175856.447245-1-mitulkumar.ajitkumar.golani@intel.com

diff --git a/drivers/gpu/drm/i915/display/skl_scaler.c b/drivers/gpu/drm/i915/display/skl_scaler.c
index 3465f7878ed5bcd15468147b1cf9ef15aaa4fb43..54f9adba4ac0645a243baa8c960894e8b2c9d7a7 100644 (file)
--- a/drivers/gpu/drm/i915/display/skl_scaler.c
+++ b/drivers/gpu/drm/i915/display/skl_scaler.c
@@ -368,6 +368,8 @@ static int intel_atomic_setup_scaler(struct intel_crtc_state *crtc_state,
                                        &crtc_state->scaler_state;
        struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
        u32 mode;
+       int hscale = 0;
+       int vscale = 0;
 
        if (*scaler_id < 0)
                *scaler_id = intel_allocate_scaler(scaler_state, crtc);
@@ -416,15 +418,11 @@ static int intel_atomic_setup_scaler(struct intel_crtc_state *crtc_state,
                mode = SKL_PS_SCALER_MODE_DYN;
        }
 
-       /*
-        * FIXME: we should also check the scaler factors for pfit, so
-        * this shouldn't be tied directly to planes.
-        */
        if (plane_state && plane_state->hw.fb) {
                const struct drm_framebuffer *fb = plane_state->hw.fb;
                const struct drm_rect *src = &plane_state->uapi.src;
                const struct drm_rect *dst = &plane_state->uapi.dst;
-               int hscale, vscale, max_vscale, max_hscale;
+               int max_hscale, max_vscale;
 
                calculate_max_scale(crtc,
                                    intel_format_info_is_yuv_semiplanar(fb->format, fb->modifier),
@@ -448,11 +446,38 @@ static int intel_atomic_setup_scaler(struct intel_crtc_state *crtc_state,
 
                        return -EINVAL;
                }
+       }
+
+       if (crtc_state->pch_pfit.enabled) {
+               struct drm_rect src;
+               int max_hscale, max_vscale;
+
+               drm_rect_init(&src, 0, 0,
+                             drm_rect_width(&crtc_state->pipe_src) << 16,
+                             drm_rect_height(&crtc_state->pipe_src) << 16);
+
+               calculate_max_scale(crtc, 0, *scaler_id,
+                                   &max_hscale, &max_vscale);
 
-               scaler_state->scalers[*scaler_id].hscale = hscale;
-               scaler_state->scalers[*scaler_id].vscale = vscale;
+               hscale = drm_rect_calc_hscale(&src, &crtc_state->pch_pfit.dst,
+                                             0, max_hscale);
+               vscale = drm_rect_calc_vscale(&src, &crtc_state->pch_pfit.dst,
+                                             0, max_vscale);
+
+               if (hscale < 0 || vscale < 0) {
+                       drm_dbg_kms(display->drm,
+                                   "Scaler %d doesn't support required pipe scaling\n",
+                                   *scaler_id);
+                       drm_rect_debug_print("src: ", &src, true);
+                       drm_rect_debug_print("dst: ", &crtc_state->pch_pfit.dst, false);
+
+                       return -EINVAL;
+               }
        }
 
+       scaler_state->scalers[*scaler_id].hscale = hscale;
+       scaler_state->scalers[*scaler_id].vscale = vscale;
+
        drm_dbg_kms(display->drm, "[CRTC:%d:%s] attached scaler id %u.%u to %s:%d\n",
                    crtc->base.base.id, crtc->base.name,
                    crtc->pipe, *scaler_id, name, idx);