drm/i915/dp: Refactor joiner max_bpp calculations into separate functions

Currently compressed max_bpp limitations for small joiner ram, big joiner
etc are intermingled. Seprate these limitations into separate functions.

v2: Use num_joined_pipes in small joiner ram helper and other minor
fixes. (Ville)

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240930163549.416410-8-ankit.k.nautiyal@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index f2a2541c10918c68f03f31f011245bc08f56b506..29f8cb9c4dd00e8e74f7377e8c7cd467682c4e6b 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -859,25 +859,51 @@ u32 intel_dp_dsc_nearest_valid_bpp(struct drm_i915_private *i915, u32 bpp, u32 p
        return bits_per_pixel;
 }
 
+static int bigjoiner_interface_bits(struct intel_display *display)
+{
+       return DISPLAY_VER(display) >= 14 ? 36 : 24;
+}
+
+static u32 bigjoiner_bw_max_bpp(struct intel_display *display, u32 mode_clock)
+{
+       u32 max_bpp;
+       /* With bigjoiner multiple dsc engines are used in parallel so PPC is 2 */
+       int ppc = 2;
+
+       max_bpp = display->cdclk.max_cdclk_freq * ppc * bigjoiner_interface_bits(display) /
+                 intel_dp_mode_to_fec_clock(mode_clock);
+
+       return max_bpp;
+}
+
+static u32 small_joiner_ram_max_bpp(struct intel_display *display,
+                                   u32 mode_hdisplay,
+                                   int num_joined_pipes)
+{
+       struct drm_i915_private *i915 = to_i915(display->drm);
+       u32 max_bpp;
+
+       /* Small Joiner Check: output bpp <= joiner RAM (bits) / Horiz. width */
+       max_bpp = small_joiner_ram_size_bits(i915) / mode_hdisplay;
+
+       max_bpp *= num_joined_pipes;
+
+       return max_bpp;
+}
+
 static
 u32 get_max_compressed_bpp_with_joiner(struct drm_i915_private *i915,
                                       u32 mode_clock, u32 mode_hdisplay,
                                       int num_joined_pipes)
 {
+       struct intel_display *display = to_intel_display(&i915->drm);
        u32 max_bpp_small_joiner_ram;
 
-       /* Small Joiner Check: output bpp <= joiner RAM (bits) / Horiz. width */
-       max_bpp_small_joiner_ram = small_joiner_ram_size_bits(i915) / mode_hdisplay;
+       max_bpp_small_joiner_ram = small_joiner_ram_max_bpp(display, mode_hdisplay,
+                                                           num_joined_pipes);
 
        if (num_joined_pipes == 2) {
-               int bigjoiner_interface_bits = DISPLAY_VER(i915) >= 14 ? 36 : 24;
-               /* With bigjoiner multiple dsc engines are used in parallel so PPC is 2 */
-               int ppc = 2;
-               u32 max_bpp_bigjoiner =
-                       i915->display.cdclk.max_cdclk_freq * ppc * bigjoiner_interface_bits /
-                       intel_dp_mode_to_fec_clock(mode_clock);
-
-               max_bpp_small_joiner_ram *= 2;
+               u32 max_bpp_bigjoiner = bigjoiner_bw_max_bpp(display, mode_clock);
 
                return min(max_bpp_small_joiner_ram, max_bpp_bigjoiner);
        }