drm/i915: Use REG_FIELD_GET() to extract skl+ wm latencies

Replace the hand rolled stuff with REG_FIELD_GET() for reading
out the skl+ watermark latencies.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220908191646.20239-4-ville.syrjala@linux.intel.comReviewed-by: Jani Nikula <jani.nikula@intel.com>

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

@@ -3239,13 +3239,10 @@ static void skl_read_wm_latency(struct drm_i915_private *i915, u16 wm[])
 		return;
 	}
 
-	wm[0] = (val & GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
-	wm[1] = ((val >> GEN9_MEM_LATENCY_LEVEL_1_5_SHIFT) &
-		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
-	wm[2] = ((val >> GEN9_MEM_LATENCY_LEVEL_2_6_SHIFT) &
-		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
-	wm[3] = ((val >> GEN9_MEM_LATENCY_LEVEL_3_7_SHIFT) &
-		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
+	wm[0] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_0_4_MASK, val) * mult;
+	wm[1] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_1_5_MASK, val) * mult;
+	wm[2] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_2_6_MASK, val) * mult;
+	wm[3] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_3_7_MASK, val) * mult;
 
 	/* read the second set of memory latencies[4:7] */
 	val = 1; /* data0 to be programmed to 1 for second set */
@@ -3255,13 +3252,10 @@ static void skl_read_wm_latency(struct drm_i915_private *i915, u16 wm[])
 		return;
 	}
 
-	wm[4] = (val & GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
-	wm[5] = ((val >> GEN9_MEM_LATENCY_LEVEL_1_5_SHIFT) &
-		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
-	wm[6] = ((val >> GEN9_MEM_LATENCY_LEVEL_2_6_SHIFT) &
-		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
-	wm[7] = ((val >> GEN9_MEM_LATENCY_LEVEL_3_7_SHIFT) &
-		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
+	wm[4] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_0_4_MASK, val) * mult;
+	wm[5] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_1_5_MASK, val) * mult;
+	wm[6] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_2_6_MASK, val) * mult;
+	wm[7] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_3_7_MASK, val) * mult;
 
 	adjust_wm_latency(i915, wm, max_level, read_latency);
 }

drivers/gpu/drm/i915/i915_reg.h

@@ -6551,10 +6551,10 @@
 #define     GEN6_DECODE_RC6_VID(vids)		(((vids) * 5) + 245)
 #define   BDW_PCODE_DISPLAY_FREQ_CHANGE_REQ	0x18
 #define   GEN9_PCODE_READ_MEM_LATENCY		0x6
-#define     GEN9_MEM_LATENCY_LEVEL_MASK		0xFF
-#define     GEN9_MEM_LATENCY_LEVEL_1_5_SHIFT	8
-#define     GEN9_MEM_LATENCY_LEVEL_2_6_SHIFT	16
-#define     GEN9_MEM_LATENCY_LEVEL_3_7_SHIFT	24
+#define     GEN9_MEM_LATENCY_LEVEL_3_7_MASK	REG_GENMASK(31, 24)
+#define     GEN9_MEM_LATENCY_LEVEL_2_6_MASK	REG_GENMASK(23, 16)
+#define     GEN9_MEM_LATENCY_LEVEL_1_5_MASK	REG_GENMASK(15, 8)
+#define     GEN9_MEM_LATENCY_LEVEL_0_4_MASK	REG_GENMASK(7, 0)
 #define   SKL_PCODE_LOAD_HDCP_KEYS		0x5
 #define   SKL_PCODE_CDCLK_CONTROL		0x7
 #define     SKL_CDCLK_PREPARE_FOR_CHANGE	0x3