drm/i915/ehl: Restrict w/a 1607087056 for EHL/JSL

This w/a is fixed in B0 stepping and needs to be restricted for
A0 stepping only.
Bspec: 33451
Signed-off-by: Swathi Dhanavanthri <swathi.dhanavanthri@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200512180050.6785-1-swathi.dhanavanthri@intel.com

drivers/gpu/drm/i915/gt/intel_workarounds.c

@@ -917,10 +917,13 @@ icl_gt_workarounds_init(struct drm_i915_private *i915, struct i915_wa_list *wal)
 		    GAMT_CHKN_BIT_REG,
 		    GAMT_CHKN_DISABLE_L3_COH_PIPE);
 
-	/* Wa_1607087056:icl */
+	/* Wa_1607087056:icl,ehl,jsl */
+	if (IS_ICELAKE(i915) ||
+	    IS_EHL_REVID(i915, EHL_REVID_A0, EHL_REVID_A0)) {
 		wa_write_or(wal,
 			    SLICE_UNIT_LEVEL_CLKGATE,
 			    L3_CLKGATE_DIS | L3_CR2X_CLKGATE_DIS);
+	}
 }
 
 static void

drivers/gpu/drm/i915/i915_drv.h

@@ -1514,6 +1514,11 @@ IS_SUBPLATFORM(const struct drm_i915_private *i915,
 #define IS_ICL_REVID(p, since, until) \
 	(IS_ICELAKE(p) && IS_REVID(p, since, until))
 
+#define EHL_REVID_A0            0x0
+
+#define IS_EHL_REVID(p, since, until) \
+	(IS_ELKHARTLAKE(p) && IS_REVID(p, since, until))
+
 #define TGL_REVID_A0		0x0
 #define TGL_REVID_B0		0x1
 #define TGL_REVID_C0		0x2