drm/i915/hsw+: Add has_fuses power well attribute

The pattern of a power well backing a set of fuses whose initialization
we need to wait for during power well enabling is common to all GEN9+
platforms. Adding support for this to the HSW power well enable helper
allows us to use the HSW/BDW power well code for GEN9+ as well in a
follow-up patch.

v2:
- Use an enum for power gates instead of raw numbers. (Ville)

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170711204236.5618-6-imre.deak@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/gvt/display.c

@@ -178,9 +178,9 @@ static void emulate_monitor_status_change(struct intel_vgpu *vgpu)
 				SDE_PORTE_HOTPLUG_SPT);
 		vgpu_vreg(vgpu, SKL_FUSE_STATUS) |=
 				SKL_FUSE_DOWNLOAD_STATUS |
-				SKL_FUSE_PG0_DIST_STATUS |
-				SKL_FUSE_PG1_DIST_STATUS |
-				SKL_FUSE_PG2_DIST_STATUS;
+				SKL_FUSE_PG_DIST_STATUS(SKL_PG0) |
+				SKL_FUSE_PG_DIST_STATUS(SKL_PG1) |
+				SKL_FUSE_PG_DIST_STATUS(SKL_PG2);
 		vgpu_vreg(vgpu, LCPLL1_CTL) |=
 				LCPLL_PLL_ENABLE |
 				LCPLL_PLL_LOCK;

drivers/gpu/drm/i915/i915_drv.h

@@ -1397,6 +1397,7 @@ struct i915_power_well {
 			u8 irq_pipe_mask;
 			/* The pw is backing the VGA functionality */
 			bool has_vga:1;
+			bool has_fuses:1;
 		} hsw;
 	};
 	const struct i915_power_well_ops *ops;

drivers/gpu/drm/i915/i915_reg.h

@@ -8023,11 +8023,17 @@ enum {
 #define HSW_PWR_WELL_CTL6			_MMIO(0x45414)
 
 /* SKL Fuse Status */
+enum skl_power_gate {
+	SKL_PG0,
+	SKL_PG1,
+	SKL_PG2,
+};
+
 #define SKL_FUSE_STATUS				_MMIO(0x42000)
-#define  SKL_FUSE_DOWNLOAD_STATUS              (1<<31)
-#define  SKL_FUSE_PG0_DIST_STATUS              (1<<27)
-#define  SKL_FUSE_PG1_DIST_STATUS              (1<<26)
-#define  SKL_FUSE_PG2_DIST_STATUS              (1<<25)
+#define  SKL_FUSE_DOWNLOAD_STATUS		(1<<31)
+/* PG0 (HW control->no power well ID), PG1..PG2 (SKL_DISP_PW1..SKL_DISP_PW2) */
+#define  SKL_PW_TO_PG(pw)			((pw) - SKL_DISP_PW_1 + SKL_PG1)
+#define  SKL_FUSE_PG_DIST_STATUS(pg)		(1 << (27 - (pg)))
 
 /* Per-pipe DDI Function Control */
 #define _TRANS_DDI_FUNC_CTL_A		0x60400

drivers/gpu/drm/i915/intel_runtime_pm.c

@@ -400,16 +400,43 @@ static void hsw_wait_for_power_well_disable(struct drm_i915_private *dev_priv,
 		      !!(reqs & 1), !!(reqs & 2), !!(reqs & 4), !!(reqs & 8));
 }
 
+static void gen9_wait_for_power_well_fuses(struct drm_i915_private *dev_priv,
+					   enum skl_power_gate pg)
+{
+	/* Timeout 5us for PG#0, for other PGs 1us */
+	WARN_ON(intel_wait_for_register(dev_priv, SKL_FUSE_STATUS,
+					SKL_FUSE_PG_DIST_STATUS(pg),
+					SKL_FUSE_PG_DIST_STATUS(pg), 1));
+}
+
 static void hsw_power_well_enable(struct drm_i915_private *dev_priv,
 				  struct i915_power_well *power_well)
 {
 	enum i915_power_well_id id = power_well->id;
+	bool wait_fuses = power_well->hsw.has_fuses;
+	enum skl_power_gate pg;
 	u32 val;
 
+	if (wait_fuses) {
+		pg = SKL_PW_TO_PG(id);
+		/*
+		 * For PW1 we have to wait both for the PW0/PG0 fuse state
+		 * before enabling the power well and PW1/PG1's own fuse
+		 * state after the enabling. For all other power wells with
+		 * fuses we only have to wait for that PW/PG's fuse state
+		 * after the enabling.
+		 */
+		if (pg == SKL_PG1)
+			gen9_wait_for_power_well_fuses(dev_priv, SKL_PG0);
+	}
+
 	val = I915_READ(HSW_PWR_WELL_DRIVER);
 	I915_WRITE(HSW_PWR_WELL_DRIVER, val | HSW_PWR_WELL_CTL_REQ(id));
 	hsw_wait_for_power_well_enable(dev_priv, power_well);
 
+	if (wait_fuses)
+		gen9_wait_for_power_well_fuses(dev_priv, pg);
+
 	hsw_power_well_post_enable(dev_priv, power_well->hsw.irq_pipe_mask,
 				   power_well->hsw.has_vga);
 }
@@ -810,15 +837,15 @@ static void skl_set_power_well(struct drm_i915_private *dev_priv,
 	case SKL_DISP_PW_1:
 		if (intel_wait_for_register(dev_priv,
 					    SKL_FUSE_STATUS,
-					    SKL_FUSE_PG0_DIST_STATUS,
-					    SKL_FUSE_PG0_DIST_STATUS,
+					    SKL_FUSE_PG_DIST_STATUS(SKL_PG0),
+					    SKL_FUSE_PG_DIST_STATUS(SKL_PG0),
 					    1)) {
 			DRM_ERROR("PG0 not enabled\n");
 			return;
 		}
 		break;
 	case SKL_DISP_PW_2:
-		if (!(fuse_status & SKL_FUSE_PG1_DIST_STATUS)) {
+		if (!(fuse_status & SKL_FUSE_PG_DIST_STATUS(SKL_PG1))) {
 			DRM_ERROR("PG1 in disabled state\n");
 			return;
 		}
@@ -863,15 +890,15 @@ static void skl_set_power_well(struct drm_i915_private *dev_priv,
 		if (power_well->id == SKL_DISP_PW_1) {
 			if (intel_wait_for_register(dev_priv,
 						    SKL_FUSE_STATUS,
-						    SKL_FUSE_PG1_DIST_STATUS,
-						    SKL_FUSE_PG1_DIST_STATUS,
+						    SKL_FUSE_PG_DIST_STATUS(SKL_PG1),
+						    SKL_FUSE_PG_DIST_STATUS(SKL_PG1),
 						    1))
 				DRM_ERROR("PG1 distributing status timeout\n");
 		} else if (power_well->id == SKL_DISP_PW_2) {
 			if (intel_wait_for_register(dev_priv,
 						    SKL_FUSE_STATUS,
-						    SKL_FUSE_PG2_DIST_STATUS,
-						    SKL_FUSE_PG2_DIST_STATUS,
+						    SKL_FUSE_PG_DIST_STATUS(SKL_PG2),
+						    SKL_FUSE_PG_DIST_STATUS(SKL_PG2),
 						    1))
 				DRM_ERROR("PG2 distributing status timeout\n");
 		}