3 files changed, 46 insertions, 0 deletions

diff --git a/src/soc/intel/broadwell/igd.c b/src/soc/intel/broadwell/igd.c
index ccb1e93604..c1cfdd81d7 100644
--- a/src/soc/intel/broadwell/igd.c
+++ b/src/soc/intel/broadwell/igd.c
@@ -31,6 +31,7 @@
 #include <soc/systemagent.h>
 #include <soc/intel/broadwell/chip.h>
 #include <vboot/vbnv.h>
+#include <soc/igd.h>
 
 #define GT_RETRY 		1000
 #define GT_CDCLK_337		0
@@ -38,6 +39,12 @@
 #define GT_CDCLK_540		2
 #define GT_CDCLK_675		3
 
+static u32 reg_em4;
+static u32 reg_em5;
+
+u32 igd_get_reg_em4(void) { return reg_em4; }
+u32 igd_get_reg_em5(void) { return reg_em5; }
+
 struct reg_script haswell_early_init_script[] = {
 	/* Enable Force Wake */
 	REG_RES_WRITE32(PCI_BASE_ADDRESS_0, 0xa180, 0x00000020),
@@ -364,14 +371,20 @@ static void igd_cdclk_init_haswell(struct device *dev)
 	case GT_CDCLK_337:
 		dpdiv = 169;
 		lpcll = (1 << 26);
+		reg_em4 = 16;
+		reg_em5 = 225;
 		break;
 	case GT_CDCLK_450:
 		dpdiv = 225;
 		lpcll = 0;
+		reg_em4 = 4;
+		reg_em5 = 75;
 		break;
 	case GT_CDCLK_540:
 		dpdiv = 270;
 		lpcll = (1 << 26);
+		reg_em4 = 4;
+		reg_em5 = 90;
 		break;
 	default:
 		return;
@@ -432,24 +445,32 @@ static void igd_cdclk_init_broadwell(struct device *dev)
 		lpcll = (1 << 27);
 		pwctl = 2;
 		dpdiv = 169;
+		reg_em4 = 16;
+		reg_em5 = 225;
 		break;
 	case GT_CDCLK_450:
 		cdset = 449;
 		lpcll = 0;
 		pwctl = 0;
 		dpdiv = 225;
+		reg_em4 = 4;
+		reg_em5 = 75;
 		break;
 	case GT_CDCLK_540:
 		cdset = 539;
 		lpcll = (1 << 26);
 		pwctl = 1;
 		dpdiv = 270;
+		reg_em4 = 4;
+		reg_em5 = 90;
 		break;
 	case GT_CDCLK_675:
 		cdset = 674;
 		lpcll = (1 << 26) | (1 << 27);
 		pwctl = 3;
 		dpdiv = 338;
+		reg_em4 = 8;
+		reg_em5 = 225;
 	default:
 		return;
 	}
diff --git a/src/soc/intel/broadwell/include/soc/igd.h b/src/soc/intel/broadwell/include/soc/igd.h
new file mode 100644
index 0000000000..e7d3777045
--- /dev/null
+++ b/src/soc/intel/broadwell/include/soc/igd.h
@@ -0,0 +1,20 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef SOC_INTEL_BROADWELL_GMA_H
+#define SOC_INTEL_BROADWELL_GMA_H
+
+u32 igd_get_reg_em4(void);
+u32 igd_get_reg_em5(void);
+
+#endif /* SOC_INTEL_BROADWELL_GMA_H */
\ No newline at end of file
diff --git a/src/soc/intel/broadwell/minihd.c b/src/soc/intel/broadwell/minihd.c
index 5014b08e7b..a9fc3d688b 100644
--- a/src/soc/intel/broadwell/minihd.c
+++ b/src/soc/intel/broadwell/minihd.c
@@ -25,6 +25,7 @@
 #include <stdlib.h>
 #include <soc/intel/common/hda_verb.h>
 #include <soc/ramstage.h>
+#include <soc/igd.h>
 
 static const u32 minihd_verb_table[] = {
 	/* coreboot specific header */
@@ -101,6 +102,10 @@ static void minihd_init(struct device *dev)
 					       minihd_verb_table);
 		}
 	}
+
+	/* Set EM4/EM5 registers */
+	write32(base + 0x0100c, igd_get_reg_em4());
+	write32(base + 0x01010, igd_get_reg_em5());
 }
 
 static struct device_operations minihd_ops = {