drm/i915: move dp clock computations to encoder->compute_config

With the exception of hsw, which has dedicated DP clocks which run at
the fixed frequency already, and vlv, which doesn't have optmized
pre-defined dp clock parameters (yet).

v2: Ville asked me to elaborate a bit more on the longer-term goals
wrt dpll settings computation:

So ultimately my idea is that in the compute config stage first the crtc
code puts the default platform pll limits into the pipe_config. Then
encoders can either overwrite that limit structure with their own special
stuff (mostly for lvds madness). Or they can pick some or all of the
parameters (e.g. just the p2 switchover on hdmi, or all the clock
parameters for dp/sdvo tv).

Once that's done then the generic crtc code can fill out any missing bits
(using the find_best_pll code) and then try to assign which pll to use (if
it's a platform with shared plls). In the end the modeset could should
simply write the computed stuff into registers and never be able to fail.

Of course there's still a lot of data to be moved into pipe_config to make
this all happen, hence some of the temporary ugliness.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> (v1)
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 45 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 1ccf853e2df..f63973ad33c 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -660,6 +660,49 @@ intel_dp_i2c_init(struct intel_dp *intel_dp,
 	return ret;
 }
 
+static void
+intel_dp_set_clock(struct intel_encoder *encoder,
+		   struct intel_crtc_config *pipe_config, int link_bw)
+{
+	struct drm_device *dev = encoder->base.dev;
+
+	if (IS_G4X(dev)) {
+		if (link_bw == DP_LINK_BW_1_62) {
+			pipe_config->dpll.p1 = 2;
+			pipe_config->dpll.p2 = 10;
+			pipe_config->dpll.n = 2;
+			pipe_config->dpll.m1 = 23;
+			pipe_config->dpll.m2 = 8;
+		} else {
+			pipe_config->dpll.p1 = 1;
+			pipe_config->dpll.p2 = 10;
+			pipe_config->dpll.n = 1;
+			pipe_config->dpll.m1 = 14;
+			pipe_config->dpll.m2 = 2;
+		}
+		pipe_config->clock_set = true;
+	} else if (IS_HASWELL(dev)) {
+		/* Haswell has special-purpose DP DDI clocks. */
+	} else if (HAS_PCH_SPLIT(dev)) {
+		if (link_bw == DP_LINK_BW_1_62) {
+			pipe_config->dpll.n = 1;
+			pipe_config->dpll.p1 = 2;
+			pipe_config->dpll.p2 = 10;
+			pipe_config->dpll.m1 = 12;
+			pipe_config->dpll.m2 = 9;
+		} else {
+			pipe_config->dpll.n = 2;
+			pipe_config->dpll.p1 = 1;
+			pipe_config->dpll.p2 = 10;
+			pipe_config->dpll.m1 = 14;
+			pipe_config->dpll.m2 = 8;
+		}
+		pipe_config->clock_set = true;
+	} else if (IS_VALLEYVIEW(dev)) {
+		/* FIXME: Need to figure out optimized DP clocks for vlv. */
+	}
+}
+
 bool
 intel_dp_compute_config(struct intel_encoder *encoder,
 			struct intel_crtc_config *pipe_config)
@@ -765,6 +808,8 @@ found:
 	}
 	pipe_config->pipe_bpp = bpp;
 
+	intel_dp_set_clock(encoder, pipe_config, intel_dp->link_bw);
+
 	return true;
 }