drm/i915: New offset for reading frequencies on CHV.

Use new Sideband offset to read max/min/gaur freq based on the SKU it
is running on. Based on the Number of EU, we read different bits to
identify the max frequencies at which system can run.

v2: reuse mask definitions & INTEL_INFO() to get device info (Ville)

v3: add break in switch conditions (Ville)
Signed-off-by: NDeepak S <deepak.s@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_reg.h

@@ -605,6 +605,15 @@ enum punit_power_well {
 #define PUNIT_FUSE_BUS2				0xf6 /* bits 47:40 */
 #define PUNIT_FUSE_BUS1				0xf5 /* bits 55:48 */
 
+#define FB_GFX_FMAX_AT_VMAX_FUSE		0x136
+#define FB_GFX_FREQ_FUSE_MASK			0xff
+#define FB_GFX_FMAX_AT_VMAX_2SS4EU_FUSE_SHIFT	24
+#define FB_GFX_FMAX_AT_VMAX_2SS6EU_FUSE_SHIFT	16
+#define FB_GFX_FMAX_AT_VMAX_2SS8EU_FUSE_SHIFT	8
+
+#define FB_GFX_FMIN_AT_VMIN_FUSE		0x137
+#define FB_GFX_FMIN_AT_VMIN_FUSE_SHIFT		8
+
 #define PUNIT_GPU_STATUS_REG			0xdb
 #define PUNIT_GPU_STATUS_MAX_FREQ_SHIFT	16
 #define PUNIT_GPU_STATUS_MAX_FREQ_MASK		0xff

drivers/gpu/drm/i915/intel_pm.c

@@ -4338,11 +4338,35 @@ void gen6_update_ring_freq(struct drm_device *dev)
 
 static int cherryview_rps_max_freq(struct drm_i915_private *dev_priv)
 {
+	struct drm_device *dev = dev_priv->dev;
 	u32 val, rp0;
 
-	val = vlv_punit_read(dev_priv, PUNIT_GPU_STATUS_REG);
-	rp0 = (val >> PUNIT_GPU_STATUS_MAX_FREQ_SHIFT) & PUNIT_GPU_STATUS_MAX_FREQ_MASK;
+	if (dev->pdev->revision >= 0x20) {
+		val = vlv_punit_read(dev_priv, FB_GFX_FMAX_AT_VMAX_FUSE);
 
+		switch (INTEL_INFO(dev)->eu_total) {
+		case 8:
+				/* (2 * 4) config */
+				rp0 = (val >> FB_GFX_FMAX_AT_VMAX_2SS4EU_FUSE_SHIFT);
+				break;
+		case 12:
+				/* (2 * 6) config */
+				rp0 = (val >> FB_GFX_FMAX_AT_VMAX_2SS6EU_FUSE_SHIFT);
+				break;
+		case 16:
+				/* (2 * 8) config */
+		default:
+				/* Setting (2 * 8) Min RP0 for any other combination */
+				rp0 = (val >> FB_GFX_FMAX_AT_VMAX_2SS8EU_FUSE_SHIFT);
+				break;
+		}
+		rp0 = (rp0 & FB_GFX_FREQ_FUSE_MASK);
+	} else {
+		/* For pre-production hardware */
+		val = vlv_punit_read(dev_priv, PUNIT_GPU_STATUS_REG);
+		rp0 = (val >> PUNIT_GPU_STATUS_MAX_FREQ_SHIFT) &
+		       PUNIT_GPU_STATUS_MAX_FREQ_MASK;
+	}
 	return rp0;
 }
 
@@ -4358,20 +4382,36 @@ static int cherryview_rps_rpe_freq(struct drm_i915_private *dev_priv)
 
 static int cherryview_rps_guar_freq(struct drm_i915_private *dev_priv)
 {
+	struct drm_device *dev = dev_priv->dev;
 	u32 val, rp1;
 
-	val = vlv_punit_read(dev_priv, PUNIT_REG_GPU_FREQ_STS);
-	rp1 = (val >> PUNIT_GPU_STATUS_MAX_FREQ_SHIFT) & PUNIT_GPU_STATUS_MAX_FREQ_MASK;
-
+	if (dev->pdev->revision >= 0x20) {
+		val = vlv_punit_read(dev_priv, FB_GFX_FMAX_AT_VMAX_FUSE);
+		rp1 = (val & FB_GFX_FREQ_FUSE_MASK);
+	} else {
+		/* For pre-production hardware */
+		val = vlv_punit_read(dev_priv, PUNIT_REG_GPU_FREQ_STS);
+		rp1 = ((val >> PUNIT_GPU_STATUS_MAX_FREQ_SHIFT) &
+		       PUNIT_GPU_STATUS_MAX_FREQ_MASK);
+	}
 	return rp1;
 }
 
 static int cherryview_rps_min_freq(struct drm_i915_private *dev_priv)
 {
+	struct drm_device *dev = dev_priv->dev;
 	u32 val, rpn;
 
-	val = vlv_punit_read(dev_priv, PUNIT_GPU_STATUS_REG);
-	rpn = (val >> PUNIT_GPU_STATIS_GFX_MIN_FREQ_SHIFT) & PUNIT_GPU_STATUS_GFX_MIN_FREQ_MASK;
+	if (dev->pdev->revision >= 0x20) {
+		val = vlv_punit_read(dev_priv, FB_GFX_FMIN_AT_VMIN_FUSE);
+		rpn = ((val >> FB_GFX_FMIN_AT_VMIN_FUSE_SHIFT) &
+		       FB_GFX_FREQ_FUSE_MASK);
+	} else { /* For pre-production hardware */
+		val = vlv_punit_read(dev_priv, PUNIT_GPU_STATUS_REG);
+		rpn = ((val >> PUNIT_GPU_STATIS_GFX_MIN_FREQ_SHIFT) &
+		       PUNIT_GPU_STATUS_GFX_MIN_FREQ_MASK);
+	}
+
 	return rpn;
 }