[PATCH v2] drm/i915: Fix ICL+ HDMI clock readout

Ville Syrjala
2018-09-03T14:28:50Z

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Copy the 38.4 vs. 19.2 MHz ref clock exception from the dpll
mgr into the clock readout function as well.

v2: Refactor the code into a common function
s/is_icl/gen11+/ (Rodrigo)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107722
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> #v1
---
drivers/gpu/drm/i915/intel_ddi.c | 2 +-
drivers/gpu/drm/i915/intel_dpll_mgr.c | 23 +++++++++++++++--------
drivers/gpu/drm/i915/intel_dpll_mgr.h | 1 +
3 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index f3b115ce4029..3e64488a2b0a 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -1414,7 +1414,7 @@ static int cnl_calc_wrpll_link(struct drm_i915_private *dev_priv,
break;
}

- ref_clock = dev_priv->cdclk.hw.ref;
+ ref_clock = cnl_hdmi_pll_ref_clock(dev_priv);

dco_freq = (cfgcr0 & DPLL_CFGCR0_DCO_INTEGER_MASK) * ref_clock;

diff --git a/drivers/gpu/drm/i915/intel_dpll_mgr.c b/drivers/gpu/drm/i915/intel_dpll_mgr.c
index 04d41bc1a4bb..e6cac9225536 100644
--- a/drivers/gpu/drm/i915/intel_dpll_mgr.c
+++ b/drivers/gpu/drm/i915/intel_dpll_mgr.c
@@ -2212,6 +2212,20 @@ static void cnl_wrpll_params_populate(struct skl_wrpll_params *params,
params->dco_fraction = dco & 0x7fff;
}

+int cnl_hdmi_pll_ref_clock(struct drm_i915_private *dev_priv)
+{
+ int ref_clock = dev_priv->cdclk.hw.ref;
+
+ /*
+ * For ICL+, the spec states: if reference frequency is 38.4,
+ * use 19.2 because the DPLL automatically divides that by 2.
+ */
+ if (INTEL_GEN(dev_priv) >= 11 && ref_clock == 38400)
+ ref_clock = 19200;
+
+ return ref_clock;
+}
+
static bool
cnl_ddi_calculate_wrpll(int clock,
struct drm_i915_private *dev_priv,
@@ -2251,14 +2265,7 @@ cnl_ddi_calculate_wrpll(int clock,

cnl_wrpll_get_multipliers(best_div, &pdiv, &qdiv, &kdiv);

- ref_clock = dev_priv->cdclk.hw.ref;
-
- /*
- * For ICL, the spec states: if reference frequency is 38.4, use 19.2
- * because the DPLL automatically divides that by 2.
- */
- if (IS_ICELAKE(dev_priv) && ref_clock == 38400)
- ref_clock = 19200;
+ ref_clock = cnl_hdmi_pll_ref_clock(dev_priv);

cnl_wrpll_params_populate(wrpll_params, best_dco, ref_clock, pdiv, qdiv,
kdiv);
diff --git a/drivers/gpu/drm/i915/intel_dpll_mgr.h b/drivers/gpu/drm/i915/intel_dpll_mgr.h
index 7e522cf4f13f..bf0de8a4dc63 100644
--- a/drivers/gpu/drm/i915/intel_dpll_mgr.h
+++ b/drivers/gpu/drm/i915/intel_dpll_mgr.h
@@ -344,5 +344,6 @@ void intel_dpll_dump_hw_state(struct drm_i915_private *dev_priv,
struct intel_dpll_hw_state *hw_state);
int icl_calc_dp_combo_pll_link(struct drm_i915_private *dev_priv,
uint32_t pll_id);
+int cnl_hdmi_pll_ref_clock(struct drm_i915_private *dev_priv);

#endif /* _INTEL_DPLL_MGR_H_ */
--
2.16.4