disp: msm: update topology based on clock requirement

Update the topology allocation by considering the required
mode clock (vtotal x htotal x fps * fudge factor). Modes with
a clock that exceeds the maximum SDE clock will be denoted as
requiring a topology that uses two layer mixers.

Change-Id: I3c773598b0d79cb6fea9d3a0e04d89ff84d67e13
Signed-off-by: Tatenda Chipeperekwa <tatendac@codeaurora.org>

msm/sde/sde_kms.c

@@ -19,6 +19,7 @@
 #define pr_fmt(fmt)	"[drm:%s:%d] " fmt, __func__, __LINE__
 
 #include <drm/drm_crtc.h>
+#include <drm/drm_fixed.h>
 #include <linux/debugfs.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
@@ -2468,6 +2469,52 @@ static bool sde_kms_check_for_splash(struct msm_kms *kms)
 	return sde_kms->splash_data.num_splash_displays;
 }
 
+static int sde_kms_get_mixer_count(const struct msm_kms *kms,
+		const struct drm_display_mode *mode,
+		const struct msm_resource_caps_info *res, u32 *num_lm)
+{
+	struct sde_kms *sde_kms;
+	s64 mode_clock_hz = 0;
+	s64 max_mdp_clock_hz = 0;
+	s64 mdp_fudge_factor = 0;
+	s64 temp = 0;
+	s64 htotal_fp = 0;
+	s64 vtotal_fp = 0;
+	s64 vrefresh_fp = 0;
+
+	if (!num_lm) {
+		SDE_ERROR("invalid num_lm pointer\n");
+		return -EINVAL;
+	}
+
+	*num_lm = 1;
+	if (!kms || !mode || !res) {
+		SDE_ERROR("invalid input args\n");
+		return -EINVAL;
+	}
+
+	sde_kms = to_sde_kms(kms);
+
+	max_mdp_clock_hz = drm_fixp_from_fraction(
+			sde_kms->perf.max_core_clk_rate, 1);
+	mdp_fudge_factor = drm_fixp_from_fraction(105, 100); /* 1.05 */
+	htotal_fp = drm_fixp_from_fraction(mode->htotal, 1);
+	vtotal_fp = drm_fixp_from_fraction(mode->vtotal, 1);
+	vrefresh_fp = drm_fixp_from_fraction(mode->vrefresh, 1);
+
+	temp = drm_fixp_mul(htotal_fp, vtotal_fp);
+	temp = drm_fixp_mul(temp, vrefresh_fp);
+	mode_clock_hz = drm_fixp_mul(temp, mdp_fudge_factor);
+	if (mode_clock_hz > max_mdp_clock_hz ||
+			mode->hdisplay > res->max_mixer_width)
+		*num_lm = 2;
+	SDE_DEBUG("[%s] h=%d, v=%d, fps=%d, max_mdp_clk_hz=%llu, num_lm=%d\n",
+			mode->name, mode->htotal, mode->vtotal, mode->vrefresh,
+			sde_kms->perf.max_core_clk_rate, *num_lm);
+
+	return 0;
+}
+
 static void _sde_kms_null_commit(struct drm_device *dev,
 		struct drm_encoder *enc)
 {
@@ -2778,6 +2825,7 @@ static const struct msm_kms_funcs kms_funcs = {
 	.get_address_space_device = _sde_kms_get_address_space_device,
 	.postopen = _sde_kms_post_open,
 	.check_for_splash = sde_kms_check_for_splash,
+	.get_mixer_count = sde_kms_get_mixer_count,
 };
 
 /* the caller api needs to turn on clock before calling it */