drm/i915: State readout support for WRPLLs

Still tacked onto the side, but slowly getting there.

v2: Don't forget the debugfs file.

v3 (from Paulo): Don't forget to check the power domains.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_debugfs.c

@@ -2390,6 +2390,7 @@ static int i915_shared_dplls_info(struct seq_file *m, void *unused)
 		seq_printf(m, " dpll_md: 0x%08x\n", pll->hw_state.dpll_md);
 		seq_printf(m, " fp0:     0x%08x\n", pll->hw_state.fp0);
 		seq_printf(m, " fp1:     0x%08x\n", pll->hw_state.fp1);
+		seq_printf(m, " wrpll:   0x%08x\n", pll->hw_state.wrpll);
 	}
 	drm_modeset_unlock_all(dev);
 

drivers/gpu/drm/i915/i915_drv.h

@@ -197,6 +197,7 @@ struct intel_dpll_hw_state {
 	uint32_t dpll_md;
 	uint32_t fp0;
 	uint32_t fp1;
+	uint32_t wrpll;
 };
 
 struct intel_shared_dpll {

drivers/gpu/drm/i915/i915_reg.h

@@ -5922,6 +5922,7 @@ enum punit_power_well {
 /* WRPLL */
 #define WRPLL_CTL1			0x46040
 #define WRPLL_CTL2			0x46060
+#define WRPLL_CTL(pll)			(pll == 0 ? WRPLL_CTL1 : WRPLL_CTL2)
 #define  WRPLL_PLL_ENABLE		(1<<31)
 #define  WRPLL_PLL_SSC			(1<<28)
 #define  WRPLL_PLL_NON_SSC		(2<<28)

drivers/gpu/drm/i915/intel_ddi.c

@@ -790,6 +790,8 @@ bool intel_ddi_pll_select(struct intel_crtc *intel_crtc)
 			intel_crtc->config.ddi_pll_sel = PORT_CLK_SEL_WRPLL2;
 			intel_crtc->config.shared_dpll = DPLL_ID_WRPLL2;
 		}
+
+		intel_crtc->config.dpll_hw_state.wrpll = val;
 	}
 
 	return true;
@@ -1317,6 +1319,21 @@ int intel_ddi_get_cdclk_freq(struct drm_i915_private *dev_priv)
 	}
 }
 
+static bool hsw_ddi_pll_get_hw_state(struct drm_i915_private *dev_priv,
+				     struct intel_shared_dpll *pll,
+				     struct intel_dpll_hw_state *hw_state)
+{
+	uint32_t val;
+
+	if (!intel_display_power_enabled(dev_priv, POWER_DOMAIN_PLLS))
+		return false;
+
+	val = I915_READ(WRPLL_CTL(pll->id));
+	hw_state->wrpll = val;
+
+	return val & WRPLL_PLL_ENABLE;
+}
+
 static char *hsw_ddi_pll_names[] = {
 	"WRPLL 1",
 	"WRPLL 2",
@@ -1335,6 +1352,8 @@ void intel_ddi_pll_init(struct drm_device *dev)
 	for (i = 0; i < 2; i++) {
 		dev_priv->shared_dplls[i].id = i;
 		dev_priv->shared_dplls[i].name = hsw_ddi_pll_names[i];
+		dev_priv->shared_dplls[i].get_hw_state =
+			hsw_ddi_pll_get_hw_state;
 	}
 
 	/* The LCPLL register should be turned on by the BIOS. For now let's

drivers/gpu/drm/i915/intel_display.c

@@ -7579,6 +7579,7 @@ static void haswell_get_ddi_port_state(struct intel_crtc *crtc,
 {
 	struct drm_device *dev = crtc->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_shared_dpll *pll;
 	enum port port;
 	uint32_t tmp;
 
@@ -7597,6 +7598,13 @@ static void haswell_get_ddi_port_state(struct intel_crtc *crtc,
 		break;
 	}
 
+	if (pipe_config->shared_dpll >= 0) {
+		pll = &dev_priv->shared_dplls[pipe_config->shared_dpll];
+
+		WARN_ON(!pll->get_hw_state(dev_priv, pll,
+					   &pipe_config->dpll_hw_state));
+	}
+
 	/*
 	 * Haswell has only FDI/PCH transcoder A. It is which is connected to
 	 * DDI E. So just check whether this pipe is wired to DDI E and whether
@@ -10444,6 +10452,7 @@ intel_pipe_config_compare(struct drm_device *dev,
 	PIPE_CONF_CHECK_X(dpll_hw_state.dpll_md);
 	PIPE_CONF_CHECK_X(dpll_hw_state.fp0);
 	PIPE_CONF_CHECK_X(dpll_hw_state.fp1);
+	PIPE_CONF_CHECK_X(dpll_hw_state.wrpll);
 
 	if (IS_G4X(dev) || INTEL_INFO(dev)->gen >= 5)
 		PIPE_CONF_CHECK_I(pipe_bpp);