Falco/Slippy: Patch to refactor haswell/gma.c and mainboard/google/slippy/i915io.c

A large portion of documented registers have been initialized using macros. Only a few
undocumented registers are left out. i915io.c looks lot more cleaner by removing redundant
calls. However, some more work is required to correctly identify which calls are not required.

All the io_writes are replaced by gtt_writes.

Change-Id: I077a235652c7d5eb90346cd6e15cc48b5161e969
Signed-off-by: Furquan Shaikh <furquan@google.com>
Reviewed-on: https://gerrit.chromium.org/gerrit/66204
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Commit-Queue: Furquan Shaikh <furquan@chromium.org>
Tested-by: Furquan Shaikh <furquan@chromium.org>
(cherry picked from commit 39f3289f68b527575b0a120960ff67f78415815e)
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6600
Tested-by: build bot (Jenkins)

12 files changed, 323 insertions, 349 deletions

diff --git a/src/drivers/intel/gma/i915.h b/src/drivers/intel/gma/i915.h
index 9ef3abda1d..72301e1477 100644
--- a/src/drivers/intel/gma/i915.h
+++ b/src/drivers/intel/gma/i915.h
@@ -63,6 +63,12 @@ enum transcoder {
         TRANSCODER_EDP = 0xF,
 };
 
+enum plane {
+	PLANE_A = 0,
+	PLANE_B,
+	PLANE_C,
+};
+
 /* debug enums. These are for printks that, due to their place in the
  * middle of graphics device IO, might change timing.  Use with care
  * or not at all.
@@ -132,6 +138,7 @@ struct intel_dp {
 	u32 clock;
 	int port;
 	int pipe;
+	int plane;
 	int bpp;
 	/* i2c on aux is ... interesting.
 	 * Before you do an i2c cycle, you need to set the address.
@@ -193,7 +200,6 @@ int intel_dp_get_max_downspread(struct intel_dp *intel_dp, u8 *max_downspread);
 void ironlake_edp_panel_on(struct intel_dp *intel_dp);
 void ironlake_edp_backlight_on(struct intel_dp *intel_dp);
 /* needed only on haswell. */
-void intel_prepare_ddi_buffers(int port, int use_fdi_mode);
 void intel_ddi_prepare_link_retrain(struct intel_dp *intel_dp, int port);
 int intel_dp_aux_ch(struct intel_dp *intel_dp,
 		    uint8_t *send, int send_bytes,
@@ -262,3 +268,12 @@ int intel_dp_get_lane_count(struct intel_dp *intel_dp,
 
 int intel_dp_get_lane_align_status(struct intel_dp *intel_dp,
 				   u8 *recv);
+
+void intel_prepare_ddi(void);
+void intel_ddi_set_pipe_settings(struct intel_dp *intel_dp);
+
+void gtt_write(u32 reg, u32 data);
+u32 gtt_read(u32 reg);
+
+int i915lightup(unsigned int physbase, unsigned int mmio,
+		unsigned int gfx, unsigned int init_fb);
diff --git a/src/drivers/intel/gma/i915_reg.h b/src/drivers/intel/gma/i915_reg.h
index cbb0628856..2ee5748e75 100644
--- a/src/drivers/intel/gma/i915_reg.h
+++ b/src/drivers/intel/gma/i915_reg.h
@@ -1672,6 +1672,7 @@
 /* New registers for PCH-split platforms. Safe where new bits show up, the
  * register layout machtes with gen4 BLC_PWM_CTL[12]. */
 #define BLC_PWM_CPU_CTL2	0x48250
+#define  BLC_PWM2_ENABLE        (1<<31)
 #define BLC_PWM_CPU_CTL		0x48254
 
 #define BLM_HIST_CTL			0x48260
@@ -2978,6 +2979,7 @@
 /* Ironlake */
 
 #define CPU_VGACNTRL	0x41000
+#define  CPU_VGA_DISABLE     (1<<31)
 
 #define DIGITAL_PORT_HOTPLUG_CNTRL      0x44030
 #define  DIGITAL_PORTA_HOTPLUG_ENABLE           (1 << 4)
@@ -4391,4 +4393,8 @@
 #define  WM_DBG_DISALLOW_MAXFIFO	(1<<1)
 #define  WM_DBG_DISALLOW_SPRITE		(1<<2)
 
+/* North Display Engine Reset Warn Options */
+#define NDE_RSTWRN_OPT                  0x46408
+#define  RST_PCH_HNDSHK_EN              (1<<4)
+
 #endif /* _I915_REG_H_ */
diff --git a/src/drivers/intel/gma/intel_ddi.c b/src/drivers/intel/gma/intel_ddi.c
index 3b7dc6d83e..2b27f6eb65 100644
--- a/src/drivers/intel/gma/intel_ddi.c
+++ b/src/drivers/intel/gma/intel_ddi.c
@@ -87,7 +87,7 @@ static  u32 hsw_ddi_translations_fdi[] = {
  * in either FDI or DP modes only, as HDMI connections will work with both
  * of those.
  */
-void intel_prepare_ddi_buffers(int port, int use_fdi_mode)
+static void intel_prepare_ddi_buffers(int port, int use_fdi_mode)
 {
 	u32 reg;
 	int i;
@@ -100,11 +100,22 @@ void intel_prepare_ddi_buffers(int port, int use_fdi_mode)
 	       use_fdi_mode ? "FDI" : "DP");
 
 	for (i=0,reg=DDI_BUF_TRANS(port);i < ARRAY_SIZE(hsw_ddi_translations_fdi);i++) {
-		io_i915_write32(ddi_translations[i], reg);
+		gtt_write(reg,ddi_translations[i]);
 		reg += 4;
 	}
 }
 
+void intel_prepare_ddi(void)
+{
+	int port;
+	u32 use_fdi = 1;
+
+	for (port = PORT_A; port < PORT_E; port++)
+		intel_prepare_ddi_buffers(port, !use_fdi);
+
+	intel_prepare_ddi_buffers(PORT_E, use_fdi);
+}
+
 static void intel_wait_ddi_buf_idle(int port)
 {
 	uint32_t reg = DDI_BUF_CTL(port);
@@ -112,7 +123,7 @@ static void intel_wait_ddi_buf_idle(int port)
 
 	for (i = 0; i < 8; i++) {
 		udelay(1);
-		if (io_i915_read32(reg) & DDI_BUF_IS_IDLE){
+		if (gtt_read(reg) & DDI_BUF_IS_IDLE){
 			printk(BIOS_SPEW, "%s: buf is idle (success)\n", __func__);
 			return;
 		}
@@ -126,18 +137,18 @@ void intel_ddi_prepare_link_retrain(struct intel_dp *intel_dp, int port)
 	int wait = 0;
 	uint32_t val;
 
-	if (io_i915_read32(DP_TP_CTL(port)) & DP_TP_CTL_ENABLE) {
-		val = io_i915_read32(DDI_BUF_CTL(port));
+	if (gtt_read(DP_TP_CTL(port)) & DP_TP_CTL_ENABLE) {
+		val = gtt_read(DDI_BUF_CTL(port));
 		if (val & DDI_BUF_CTL_ENABLE) {
 			val &= ~DDI_BUF_CTL_ENABLE;
-			io_i915_write32(DDI_BUF_CTL(port), val);
+			gtt_write(val,DDI_BUF_CTL(port));
 			wait = 1;
 		}
 
-		val = io_i915_read32(DP_TP_CTL(port));
+		val = gtt_read(DP_TP_CTL(port));
 		val &= ~(DP_TP_CTL_ENABLE | DP_TP_CTL_LINK_TRAIN_MASK);
 		val |= DP_TP_CTL_LINK_TRAIN_PAT1;
-		io_i915_write32(DP_TP_CTL(port), val);
+		gtt_write(val,DP_TP_CTL(port));
 		//POSTING_READ(DP_TP_CTL(port));
 
 		if (wait)
@@ -148,11 +159,11 @@ void intel_ddi_prepare_link_retrain(struct intel_dp *intel_dp, int port)
 	      DP_TP_CTL_LINK_TRAIN_PAT1 | DP_TP_CTL_SCRAMBLE_DISABLE;
 	if (intel_dp->link_configuration[1] & DP_LANE_COUNT_ENHANCED_FRAME_EN)
 		val |= DP_TP_CTL_ENHANCED_FRAME_ENABLE;
-	io_i915_write32(DP_TP_CTL(port), val);
+	gtt_write(val,DP_TP_CTL(port));
 	//POSTING_READ(DP_TP_CTL(port));
 
 	intel_dp->DP |= DDI_BUF_CTL_ENABLE;
-	io_i915_write32(DDI_BUF_CTL(port), intel_dp->DP);
+	gtt_write(intel_dp->DP,DDI_BUF_CTL(port));
 	//POSTING_READ(DDI_BUF_CTL(port));
 
 	udelay(600);
@@ -237,3 +248,26 @@ enum transcoder intel_ddi_get_transcoder(enum port port,
 		return TRANSCODER_EDP;
 	return (enum transcoder)pipe;
 }
+
+void intel_ddi_set_pipe_settings(struct intel_dp *intel_dp)
+{
+	u32 val = TRANS_MSA_SYNC_CLK;
+
+	switch (intel_dp->bpp) {
+	case 18:
+		val |= TRANS_MSA_6_BPC;
+		break;
+	case 24:
+		val |= TRANS_MSA_8_BPC;
+		break;
+	case 30:
+		val |= TRANS_MSA_10_BPC;
+		break;
+	case 36:
+		val |= TRANS_MSA_12_BPC;
+		break;
+	default:
+		printk(BIOS_ERR, "Invalid bpp settings %d\n", intel_dp->bpp);
+	}
+	gtt_write(TRANS_MSA_MISC(intel_dp->transcoder),val);
+}
diff --git a/src/drivers/intel/gma/intel_dp.c b/src/drivers/intel/gma/intel_dp.c
index 44a947e006..833a4d6834 100644
--- a/src/drivers/intel/gma/intel_dp.c
+++ b/src/drivers/intel/gma/intel_dp.c
@@ -98,12 +98,12 @@ unpack_aux(uint32_t src, uint8_t *dst, int dst_bytes)
 static int ironlake_edp_have_panel_power(struct intel_dp *intel_dp)
 {
 
-	return (io_i915_read32(PCH_PP_STATUS) & PP_ON) != 0;
+	return (gtt_read(PCH_PP_STATUS) & PP_ON) != 0;
 }
 
 static int ironlake_edp_have_panel_vdd(struct intel_dp *intel_dp)
 {
-	return (io_i915_read32(PCH_PP_CONTROL) & EDP_FORCE_VDD) != 0;
+	return (gtt_read(PCH_PP_CONTROL) & EDP_FORCE_VDD) != 0;
 }
 
 int
@@ -121,7 +121,7 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
 
 	/* Try to wait for any previous AUX channel activity */
 	for (try = 0; try < 3; try++) {
-		status = io_i915_read32(ch_ctl);
+		status = gtt_read(ch_ctl);
 		if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
 			break;
 		mdelay(1);
@@ -129,7 +129,7 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
 
 	if (try == 3) {
 		if (1) {
-			status = io_i915_read32(ch_ctl);
+			status = gtt_read(ch_ctl);
 			printk(BIOS_ERR,
 			       "dp_aux_ch not started status 0x%08x\n",
 			       status);
@@ -144,30 +144,30 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
 			u32 val, addr;
 			val = pack_aux(send + i, send_bytes - i);
 			addr = ch_data + i;
-			io_i915_write32(val, addr);
+			gtt_write(addr,val);
 		}
 
 		/* Send the command and wait for it to complete */
-		io_i915_write32(DP_AUX_CH_CTL_SEND_BUSY |
-				DP_AUX_CH_CTL_TIME_OUT_400us |
-				(send_bytes << DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT) |
-				(intel_dp->precharge << DP_AUX_CH_CTL_PRECHARGE_2US_SHIFT) |
-				(intel_dp->aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT) |
-				DP_AUX_CH_CTL_DONE |
-				DP_AUX_CH_CTL_TIME_OUT_ERROR |
-				DP_AUX_CH_CTL_RECEIVE_ERROR, ch_ctl);
+		gtt_write(ch_ctl, DP_AUX_CH_CTL_SEND_BUSY |
+			  DP_AUX_CH_CTL_TIME_OUT_400us |
+			  (send_bytes << DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT) |
+			  (intel_dp->precharge << DP_AUX_CH_CTL_PRECHARGE_2US_SHIFT) |
+			  (intel_dp->aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT) |
+			  DP_AUX_CH_CTL_DONE |
+			  DP_AUX_CH_CTL_TIME_OUT_ERROR |
+			  DP_AUX_CH_CTL_RECEIVE_ERROR);
 		for (;;) {
-			status = io_i915_read32(ch_ctl);
+			status = gtt_read(ch_ctl);
 			if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
 				break;
 			udelay(100);
 		}
 
 		/* Clear done status and any errors */
-		io_i915_write32(status |
-				DP_AUX_CH_CTL_DONE |
-				DP_AUX_CH_CTL_TIME_OUT_ERROR |
-				DP_AUX_CH_CTL_RECEIVE_ERROR, ch_ctl);
+		gtt_write(ch_ctl, status |
+			  DP_AUX_CH_CTL_DONE |
+			  DP_AUX_CH_CTL_TIME_OUT_ERROR |
+			  DP_AUX_CH_CTL_RECEIVE_ERROR);
 
 		if (status & (DP_AUX_CH_CTL_TIME_OUT_ERROR |
 			      DP_AUX_CH_CTL_RECEIVE_ERROR))
@@ -204,7 +204,7 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
 		recv_bytes = recv_size;
 
 	for (i = 0; i < recv_bytes; i += 4)
-		unpack_aux(io_i915_read32(ch_data + i),
+		unpack_aux(gtt_read(ch_data + i),
 			   recv + i, recv_bytes - i);
 
 	return recv_bytes;
@@ -513,13 +513,11 @@ intel_dp_set_m_n(struct intel_dp *intel_dp)
 			     intel_dp->clock, intel_dp->clock, &m_n);
 
 	{
-		io_i915_write32((
-					(m_n.tu - 1) <<
-					PIPE_GMCH_DATA_M_TU_SIZE_SHIFT) |
-				m_n.gmch_m, TRANSDATA_M1(pipe));
-		io_i915_write32(m_n.gmch_n, TRANSDATA_N1(pipe));
-		io_i915_write32(m_n.link_m, TRANSDPLINK_M1(pipe));
-		io_i915_write32(m_n.link_n, TRANSDPLINK_N1(pipe));
+		gtt_write(TRANSDATA_M1(pipe),
+			  ((m_n.tu - 1) << PIPE_GMCH_DATA_M_TU_SIZE_SHIFT) |m_n.gmch_m);
+		gtt_write(TRANSDATA_N1(pipe),m_n.gmch_n);
+		gtt_write(TRANSDPLINK_M1(pipe),m_n.link_m);
+		gtt_write(TRANSDPLINK_N1(pipe),m_n.link_n);
 	}
 }
 
@@ -556,7 +554,7 @@ intel_dp_mode_set(struct intel_dp *intel_dp)
 	/* Preserve the BIOS-computed detected bit. This is
 	 * supposed to be read-only.
 	 */
-	intel_dp->DP = io_i915_read32(intel_dp->output_reg) & DP_DETECTED;
+	intel_dp->DP = gtt_read(intel_dp->output_reg) & DP_DETECTED;
 	printk(BIOS_SPEW, "%s: initial value is %08lx\n", __func__,
 	       (unsigned long)intel_dp->DP);
 	/* | 0 essentially */
@@ -654,18 +652,18 @@ static void ironlake_wait_panel_status(struct intel_dp *intel_dp,
 	printk(BIOS_ERR, "[000000.0] [drm:%s], ", __func__);
 	printk(BIOS_ERR, "mask %08lx value %08lx status %08lx control %08lx\n",
 	       (unsigned long) mask, (unsigned long) value,
-	       (unsigned long)io_i915_read32(PCH_PP_STATUS),
-	       (unsigned long)io_i915_read32(PCH_PP_CONTROL));
+	       (unsigned long)gtt_read(PCH_PP_STATUS),
+	       (unsigned long)gtt_read(PCH_PP_CONTROL));
 
-	for(i = 0, status = io_i915_read32(PCH_PP_STATUS); ((status & mask) != value) && (i < 5000);
-	    status = io_i915_read32(PCH_PP_STATUS)){
+	for(i = 0, status = gtt_read(PCH_PP_STATUS); ((status & mask) != value) && (i < 5000);
+	    status = gtt_read(PCH_PP_STATUS)){
 		udelay(10);
 	}
 	if (i > 5000){
 		printk(BIOS_ERR,
 		       "Panel status timeout: status %08lx control %08lx\n",
-		       (unsigned long)io_i915_read32(PCH_PP_STATUS),
-		       (unsigned long)io_i915_read32(PCH_PP_CONTROL));
+		       (unsigned long)gtt_read(PCH_PP_STATUS),
+		       (unsigned long)gtt_read(PCH_PP_CONTROL));
 	}
 }
 
@@ -693,7 +691,7 @@ void intel_dp_wait_reg(unsigned long addr,
 	unsigned long newval;
 	int tries = 0;
 
-	while ((newval = io_i915_read32(addr)) != val) {
+	while ((newval = gtt_read(addr)) != val) {
 		udelay(1);
 		if (tries++ > 1000) {
 			printk(BIOS_ERR, "%s: Waiting on %08lx to be %08lx, got %08lx\n",
@@ -714,7 +712,7 @@ void intel_dp_wait_panel_power_control(unsigned long val)
 
 static  u32 ironlake_get_pp_control(void)
 {
-	u32	control = io_i915_read32(PCH_PP_CONTROL);
+	u32	control = gtt_read(PCH_PP_CONTROL);
 
 	control &= ~PANEL_UNLOCK_MASK;
 	control |= PANEL_UNLOCK_REGS;
@@ -745,11 +743,12 @@ void ironlake_edp_panel_vdd_on(struct intel_dp *intel_dp)
 
 	pp = ironlake_get_pp_control();
 	pp |= EDP_FORCE_VDD;
-	io_i915_write32(pp, PCH_PP_CONTROL);
+	gtt_write(PCH_PP_CONTROL,pp);
 	// remember this if we need it later. Not sure yet.
 	////POSTING_READ(PCH_PP_CONTROL);
 	printk(BIOS_ERR, "PCH_PP_STATUS: 0x%08lx PCH_PP_CONTROL: 0x%08lx\n",
-	       io_i915_read32(PCH_PP_STATUS), io_i915_read32(PCH_PP_CONTROL));
+		(unsigned long) gtt_read(PCH_PP_STATUS),
+		(unsigned long) gtt_read(PCH_PP_CONTROL));
 
 	/*
 	 * If the panel wasn't on, delay before accessing aux channel
@@ -767,12 +766,13 @@ static void ironlake_panel_vdd_off_sync(struct intel_dp *intel_dp)
 	if (!intel_dp->want_panel_vdd && ironlake_edp_have_panel_vdd(intel_dp)) {
 		pp = ironlake_get_pp_control();
 		pp &= ~EDP_FORCE_VDD;
-		io_i915_write32(pp, PCH_PP_CONTROL);
+		gtt_write(PCH_PP_CONTROL,pp);
 		////POSTING_READ(PCH_PP_CONTROL);
 
 		/* Make sure sequencer is idle before allowing subsequent activity */
 		printk(BIOS_ERR, "PCH_PP_STATUS: 0x%08lx PCH_PP_CONTROL: 0x%08lx\n",
-		       io_i915_read32(PCH_PP_STATUS), io_i915_read32(PCH_PP_CONTROL));
+			(unsigned long) gtt_read(PCH_PP_STATUS),
+			(unsigned long) gtt_read(PCH_PP_CONTROL));
 
 		mdelay(intel_dp->panel_power_down_delay);
 	}
@@ -814,7 +814,7 @@ void ironlake_edp_panel_on(struct intel_dp *intel_dp)
 	if (intel_dp->gen == 5) {
 		/* ILK workaround: disable reset around power sequence */
 		pp &= ~PANEL_POWER_RESET;
-		io_i915_write32(pp, PCH_PP_CONTROL);
+		gtt_write(PCH_PP_CONTROL,pp);
 		////POSTING_READ(PCH_PP_CONTROL);
 	}
 
@@ -822,14 +822,14 @@ void ironlake_edp_panel_on(struct intel_dp *intel_dp)
 	if (!(intel_dp->gen == 5))
 		pp |= PANEL_POWER_RESET;
 
-	io_i915_write32(pp, PCH_PP_CONTROL);
+	gtt_write(PCH_PP_CONTROL,pp);
 	////POSTING_READ(PCH_PP_CONTROL);
 
 	ironlake_wait_panel_on(intel_dp);
 
 	if (intel_dp->gen == 5) {
 		pp |= PANEL_POWER_RESET; /* restore panel reset bit */
-		io_i915_write32(pp, PCH_PP_CONTROL);
+		gtt_write(PCH_PP_CONTROL,pp);
 		////POSTING_READ(PCH_PP_CONTROL);
 	}
 }
@@ -850,7 +850,7 @@ static void ironlake_edp_panel_off(struct intel_dp *intel_dp)
 	pp = ironlake_get_pp_control();
 	pp &= ~(POWER_TARGET_ON | EDP_FORCE_VDD |
 		PANEL_POWER_RESET | EDP_BLC_ENABLE);
-	io_i915_write32(pp, PCH_PP_CONTROL);
+	gtt_write(PCH_PP_CONTROL,pp);
 	////POSTING_READ(PCH_PP_CONTROL);
 
 	ironlake_wait_panel_off(intel_dp);
@@ -872,7 +872,7 @@ void ironlake_edp_backlight_on(struct intel_dp *intel_dp)
 	mdelay(intel_dp->backlight_on_delay);
 	pp = ironlake_get_pp_control();
 	pp |= EDP_BLC_ENABLE;
-	io_i915_write32(pp, PCH_PP_CONTROL);
+	gtt_write(PCH_PP_CONTROL,pp);
 	////POSTING_READ(PCH_PP_CONTROL);
 }
 
@@ -885,7 +885,7 @@ static void ironlake_edp_backlight_off(struct intel_dp *intel_dp)
 
 	pp = ironlake_get_pp_control();
 	pp &= ~EDP_BLC_ENABLE;
-	io_i915_write32(pp, PCH_PP_CONTROL);
+	gtt_write(PCH_PP_CONTROL,pp);
 	////POSTING_READ(PCH_PP_CONTROL);
 	mdelay(intel_dp->backlight_off_delay);
 }
@@ -894,9 +894,9 @@ void ironlake_edp_pll_on(void)
 {
 	u32 dpa_ctl;
 
-	dpa_ctl = io_i915_read32(DP_A);
+	dpa_ctl = gtt_read(DP_A);
 	dpa_ctl |= DP_PLL_ENABLE;
-	io_i915_write32(dpa_ctl, DP_A);
+	gtt_write(DP_A,dpa_ctl);
 	////POSTING_READ(DP_A);
 	udelay(200);
 }
@@ -905,9 +905,9 @@ static void ironlake_edp_pll_off(void)
 {
 	u32 dpa_ctl;
 
-	dpa_ctl = io_i915_read32(DP_A);
+	dpa_ctl = gtt_read(DP_A);
 	dpa_ctl &= ~DP_PLL_ENABLE;
-	io_i915_write32(dpa_ctl, DP_A);
+	gtt_write(DP_A,dpa_ctl);
 	////POSTING_READ(DP_A);
 	udelay(200);
 }
@@ -981,7 +981,7 @@ void intel_dp_commit(struct intel_dp *intel_dp)
 void
 intel_dp_dpms(struct intel_dp *intel_dp, int mode)
 {
-	uint32_t dp_reg = io_i915_read32(intel_dp->output_reg);
+	uint32_t dp_reg = gtt_read(intel_dp->output_reg);
 
 	printk(BIOS_SPEW, "%s: power %s\n", __func__, mode ? "off" : "on");
 	if (mode){
@@ -1402,7 +1402,7 @@ intel_dp_set_link_train(struct intel_dp *intel_dp,
 	printk(BIOS_SPEW, "%s: dp_reg_value %08lx dp_train_pat %02x\n",
 	       __func__, (unsigned long) dp_reg_value, dp_train_pat);
 	if (intel_dp->is_haswell){
-		temp = io_i915_read32(DP_TP_CTL(port));
+		temp = gtt_read(DP_TP_CTL(port));
 
 		if (dp_train_pat & DP_LINK_SCRAMBLING_DISABLE)
 			temp |= DP_TP_CTL_SCRAMBLE_DISABLE;
@@ -1413,11 +1413,11 @@ intel_dp_set_link_train(struct intel_dp *intel_dp,
 		switch (dp_train_pat & DP_TRAINING_PATTERN_MASK) {
 		case DP_TRAINING_PATTERN_DISABLE:
 			temp |= DP_TP_CTL_LINK_TRAIN_IDLE;
-			io_i915_write32( temp, DP_TP_CTL(port));
+			gtt_write(DP_TP_CTL(port), temp);
 
 			for(i = 0; i < 10; i++){
 				u32 status;
-				status = io_i915_read32(DP_TP_STATUS(port));
+				status = gtt_read(DP_TP_STATUS(port));
 				if (status & DP_TP_STATUS_IDLE_DONE)
 					break;
 			}
@@ -1440,7 +1440,7 @@ intel_dp_set_link_train(struct intel_dp *intel_dp,
 			temp |= DP_TP_CTL_LINK_TRAIN_PAT3;
 			break;
 		}
-		io_i915_write32( temp, DP_TP_CTL(port));
+		gtt_write(DP_TP_CTL(port), temp);
 
 	} else if (intel_dp->has_pch_cpt &&
 		   (intel_dp->gen != 7 || !is_cpu_edp(intel_dp))) {
@@ -1483,7 +1483,7 @@ intel_dp_set_link_train(struct intel_dp *intel_dp,
 		}
 	}
 
-	io_i915_write32( dp_reg_value, intel_dp->output_reg);
+	gtt_write(intel_dp->output_reg, dp_reg_value);
 	//POSTING_READ(intel_dp->output_reg);
 
 	intel_dp_aux_native_write_1(intel_dp,
@@ -1702,7 +1702,7 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp)
 		++tries;
 	}
 
-	//io_i915_write32(reg, intel_dp->output_reg);
+	//gtt_write(intel_dp->output_reg,reg);
 	////POSTING_READ(intel_dp->output_reg);
 	intel_dp_set_link_train(intel_dp, DP, DP_TRAINING_PATTERN_DISABLE);
 }
@@ -1712,7 +1712,7 @@ intel_dp_link_down(struct intel_dp *intel_dp)
 {
 	uint32_t DP = intel_dp->DP;
 
-	if ((io_i915_read32(intel_dp->output_reg) & DP_PORT_EN) == 0)
+	if ((gtt_read(intel_dp->output_reg) & DP_PORT_EN) == 0)
 		return;
 
 	if (intel_dp->is_haswell){
@@ -1721,17 +1721,17 @@ intel_dp_link_down(struct intel_dp *intel_dp)
 	}
 	if (is_edp(intel_dp)) {
 		DP &= ~DP_PLL_ENABLE;
-		io_i915_write32(DP, intel_dp->output_reg);
+		gtt_write(intel_dp->output_reg,DP);
 		////POSTING_READ(intel_dp->output_reg);
 		udelay(100);
 	}
 
 	if (intel_dp->has_pch_cpt && ((intel_dp->gen == 7) || !is_cpu_edp(intel_dp))) {
 		DP &= ~DP_LINK_TRAIN_MASK_CPT;
-		io_i915_write32(DP | DP_LINK_TRAIN_PAT_IDLE_CPT, intel_dp->output_reg);
+		gtt_write(intel_dp->output_reg,DP | DP_LINK_TRAIN_PAT_IDLE_CPT);
 	} else {
 		DP &= ~DP_LINK_TRAIN_MASK;
-		io_i915_write32(DP | DP_LINK_TRAIN_PAT_IDLE, intel_dp->output_reg);
+		gtt_write(intel_dp->output_reg,DP | DP_LINK_TRAIN_PAT_IDLE);
 	}
 	////POSTING_READ(intel_dp->output_reg);
 
@@ -1745,7 +1745,7 @@ intel_dp_link_down(struct intel_dp *intel_dp)
 	}
 
 	DP &= ~DP_AUDIO_OUTPUT_ENABLE;
-	io_i915_write32(DP & ~DP_PORT_EN, intel_dp->output_reg);
+	gtt_write(intel_dp->output_reg,DP & ~DP_PORT_EN);
 	////POSTING_READ(intel_dp->output_reg);
 	mdelay(600000); //intel_dp->panel_power_down_delay);
 }
@@ -1793,25 +1793,25 @@ intel_dp_get_max_downspread(struct intel_dp *intel_dp, u8 *max_downspread)
 
 void intel_dp_set_m_n_regs(struct intel_dp *intel_dp)
 {
-        io_i915_write32(0x7e4a0000, PIPE_DATA_M1(intel_dp->transcoder));
-        /* io_i915_write32(0x00800000,0x6f034); */
+        gtt_write(PIPE_DATA_M1(intel_dp->transcoder),0x7e4a0000);
+        /* gtt_write(0x6f034,0x00800000); */
         /* Write to 0x6f030 has to be 0x7e4ayyyy -- First four hex digits are important.
            However, with our formula we always see values 0x7e43yyyy (1366 panel) and
            0x7e42yyy (1280 panel) */
-        /* io_i915_write32(TU_SIZE(intel_dp->m_n.tu) | intel_dp->m_n.gmch_m,PIPE_DATA_M1(intel_dp->transcoder)); */
-        io_i915_write32(intel_dp->m_n.gmch_n, PIPE_DATA_N1(intel_dp->transcoder));
-        io_i915_write32(intel_dp->m_n.link_m, PIPE_LINK_M1(intel_dp->transcoder));
-        io_i915_write32(intel_dp->m_n.link_n, PIPE_LINK_N1(intel_dp->transcoder));
+        /* gtt_write(PIPE_DATA_M1(intel_dp->transcoder),TU_SIZE(intel_dp->m_n.tu) | intel_dp->m_n.gmch_m); */
+        gtt_write(PIPE_DATA_N1(intel_dp->transcoder),intel_dp->m_n.gmch_n);
+        gtt_write(PIPE_LINK_M1(intel_dp->transcoder),intel_dp->m_n.link_m);
+        gtt_write(PIPE_LINK_N1(intel_dp->transcoder),intel_dp->m_n.link_n);
 }
 
 void intel_dp_set_resolution(struct intel_dp *intel_dp)
 {
-        io_i915_write32(intel_dp->htotal, HTOTAL(intel_dp->transcoder));
-        io_i915_write32(intel_dp->hblank, HBLANK(intel_dp->transcoder));
-        io_i915_write32(intel_dp->hsync,  HSYNC(intel_dp->transcoder));
-        io_i915_write32(intel_dp->vtotal, VTOTAL(intel_dp->transcoder));
-        io_i915_write32(intel_dp->vblank, VBLANK(intel_dp->transcoder));
-        io_i915_write32(intel_dp->vsync,  VSYNC(intel_dp->transcoder));
+        gtt_write(HTOTAL(intel_dp->transcoder),intel_dp->htotal);
+        gtt_write(HBLANK(intel_dp->transcoder),intel_dp->hblank);
+        gtt_write(HSYNC(intel_dp->transcoder),intel_dp->hsync);
+        gtt_write(VTOTAL(intel_dp->transcoder),intel_dp->vtotal);
+        gtt_write(VBLANK(intel_dp->transcoder),intel_dp->vblank);
+        gtt_write(VSYNC(intel_dp->transcoder),intel_dp->vsync);
 }
 
 int intel_dp_get_training_pattern(struct intel_dp *intel_dp,
diff --git a/src/mainboard/google/slippy/gma.c b/src/mainboard/google/slippy/gma.c
index 4b002ecddf..7c95e40667 100644
--- a/src/mainboard/google/slippy/gma.c
+++ b/src/mainboard/google/slippy/gma.c
@@ -87,33 +87,13 @@
 
 static unsigned int *mmio;
 static unsigned int graphics;
-static unsigned short addrport;
-static unsigned short dataport;
 static unsigned int physbase;
 
-static int ioread = 0, iowrite = 0;
-
 void ug1(int);
 void ug2(int);
 void ug22(int);
 void ug3(int);
 
-unsigned long io_i915_read32(unsigned long addr)
-{
-	unsigned long val;
-	outl(addr, addrport);
-	val = inl(dataport);
-	ioread += 2;
-	return val;
-}
-
-void io_i915_write32(unsigned long val, unsigned long addr)
-{
-	outl(addr, addrport);
-	outl(val, dataport);
-	iowrite += 2;
-}
-
 /* GTT is the Global Translation Table for the graphics pipeline.
  * It is used to translate graphics addresses to physical
  * memory addresses. As in the CPU, GTTs map 4K pages.
@@ -133,6 +113,8 @@ void io_i915_write32(unsigned long val, unsigned long addr)
  * starting at physbase.
  */
 
+#define GTT_PTE_BASE (2 << 20)
+
 static void
 setgtt(int start, int end, unsigned long base, int inc)
 {
@@ -144,7 +126,8 @@ setgtt(int start, int end, unsigned long base, int inc)
 		 * the values that mrc does no
 		 * useful setup before we run this.
 		 */
-		io_i915_write32(word|1,(i*4)|1);
+		gtt_write(GTT_PTE_BASE + i * 4, word|1);
+		gtt_read(GTT_PTE_BASE + i * 4);
 	}
 }
 
@@ -157,7 +140,7 @@ static void palette(void)
 	unsigned long color = 0;
 
 	for(i = 0; i < 256; i++, color += 0x010101){
-		io_i915_write32(color, _LGC_PALETTE_A + (i<<2));
+		gtt_write(_LGC_PALETTE_A + (i<<2),color);
 	}
 }
 
@@ -251,8 +234,8 @@ void mainboard_train_link(struct intel_dp *intel_dp)
 	u8 read_val;
 	u8 link_status[DP_LINK_STATUS_SIZE];
 
-	io_i915_write32(0x80040000,DP_TP_CTL_A);
-	io_i915_write32( DP_PORT_EN | DP_LINK_TRAIN_PAT_1 | DP_LINK_TRAIN_PAT_1_CPT | DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0 | DP_PORT_WIDTH_1 | DP_PLL_FREQ_270MHZ | DP_SYNC_VS_HIGH |0x80000011,DP_A);
+	gtt_write(DP_TP_CTL(intel_dp->port),DP_TP_CTL_ENABLE | DP_TP_CTL_ENHANCED_FRAME_ENABLE);
+	gtt_write(DP_A, DP_PORT_EN | DP_LINK_TRAIN_PAT_1 | DP_LINK_TRAIN_PAT_1_CPT | DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0 | DP_PORT_WIDTH_1 | DP_PLL_FREQ_270MHZ | DP_SYNC_VS_HIGH |0x80000011);
 
 	intel_dp_get_training_pattern(intel_dp, &read_val);
 	intel_dp_set_training_pattern(intel_dp, DP_TRAINING_PATTERN_1 | DP_LINK_QUAL_PATTERN_DISABLE | DP_SYMBOL_ERROR_COUNT_BOTH);
@@ -260,7 +243,7 @@ void mainboard_train_link(struct intel_dp *intel_dp)
 	intel_dp_set_training_lane0(intel_dp, DP_TRAIN_VOLTAGE_SWING_400 | DP_TRAIN_PRE_EMPHASIS_0);
 	intel_dp_get_link_status(intel_dp, link_status);
 
-	io_i915_write32(0x80040100,DP_TP_CTL_A);
+	gtt_write(DP_TP_CTL(intel_dp->port),DP_TP_CTL_ENABLE | DP_TP_CTL_ENHANCED_FRAME_ENABLE | DP_TP_CTL_LINK_TRAIN_PAT2);
 
 	intel_dp_get_training_pattern(intel_dp, &read_val);
 	intel_dp_set_training_pattern(intel_dp, DP_TRAINING_PATTERN_2 | DP_LINK_QUAL_PATTERN_DISABLE | DP_SYMBOL_ERROR_COUNT_BOTH);
@@ -270,34 +253,54 @@ void mainboard_train_link(struct intel_dp *intel_dp)
 	intel_dp_set_training_pattern(intel_dp, DP_TRAINING_PATTERN_DISABLE | DP_LINK_QUAL_PATTERN_DISABLE | DP_SYMBOL_ERROR_COUNT_BOTH);
 }
 
-int i915lightup(unsigned int physbase, unsigned int iobase, unsigned int mmio,
-		unsigned int gfx, unsigned int init_fb);
-int i915lightup(unsigned int pphysbase, unsigned int piobase,
-		unsigned int pmmio, unsigned int pgfx, unsigned int init_fb)
+#define TEST_GFX 0
+
+#if TEST_GFX
+static void test_gfx(struct intel_dp *dp)
+{
+	int i;
+
+	/* This is a sanity test code which fills the screen with two bands --
+	   green and blue. It is very useful to ensure all the initializations
+	   are made right. Thus, to be used only for testing, not otherwise
+	*/
+	for (i = 0; i < (dp->edid.va - 4); i++) {
+		u32 *l;
+		int j;
+		u32 tcolor = 0x0ff;
+		for (j = 0; j < (dp->edid.ha-4); j++) {
+			if (j == (dp->edid.ha/2)) {
+				tcolor = 0xff00;
+			}
+			l = (u32*)(graphics + i * dp->stride + j * sizeof(tcolor));
+			memcpy(l,&tcolor,sizeof(tcolor));
+		}
+	}
+}
+#else
+static void test_gfx(struct intel_dp *dp) {}
+#endif
+
+int i915lightup(unsigned int pphysbase, unsigned int pmmio,
+		unsigned int pgfx, unsigned int init_fb)
 {
 	int must_cycle_power = 0;
 	struct intel_dp adp, *dp = &adp;
-	/* frame buffer pointer */
-	/* u32 *l; */
 	int i;
 	int edid_ok;
-	/* u32 tcolor = 0xff; */
 	int pixels = FRAME_BUFFER_BYTES/64;
 
 	mmio = (void *)pmmio;
-	addrport = piobase;
-	dataport = addrport + 4;
 	physbase = pphysbase;
 	graphics = pgfx;
 	printk(BIOS_SPEW,
 	       "i915lightup: graphics %p mmio %p"
-	       "addrport %04x physbase %08x\n",
-	       (void *)graphics, mmio, addrport, physbase);
+	       "physbase %08x\n",
+	       (void *)graphics, mmio, physbase);
 
 	void runio(struct intel_dp *dp);
 	void runlinux(struct intel_dp *dp);
-
-	dp->gen = 8; // ??
+	dp->gen = 8; // This is gen 8 which we believe is Haswell
 	dp->is_haswell = 1;
 	dp->DP = 0x2;
 	/* These values are used for training the link */
@@ -308,6 +311,7 @@ int i915lightup(unsigned int pphysbase, unsigned int piobase,
 	dp->panel_power_cycle_delay = 600;
 	dp->pipe = PIPE_A;
 	dp->port = PORT_A;
+	dp->plane = PLANE_A;
 	dp->clock = 160000;
 	dp->bpp = 32;
 	dp->type = INTEL_OUTPUT_EDP;
@@ -327,8 +331,6 @@ int i915lightup(unsigned int pphysbase, unsigned int piobase,
                 memset((void*)graphics, 0, 4096);
         }
 
-	//intel_prepare_ddi_buffers(0, 0);
-	//ironlake_edp_panel_vdd_on(dp);
 	dp->address = 0x50;
 
 	if ( !intel_dp_get_dpcd(dp) )
@@ -351,9 +353,7 @@ int i915lightup(unsigned int pphysbase, unsigned int piobase,
 
 	dp_init_dim_regs(dp);
 
-	/* more undocumented stuff. */
-	/* possibly not even needed. */
-	io_i915_write32(0x00000021,0x6f410);
+	intel_ddi_set_pipe_settings(dp);
 
 	runio(dp);
 
@@ -362,31 +362,19 @@ int i915lightup(unsigned int pphysbase, unsigned int piobase,
 	pixels = dp->edid.ha * (dp->edid.va-4) * 4;
 	printk(BIOS_SPEW, "ha=%d, va=%d\n",dp->edid.ha, dp->edid.va);
 
-	/* for (i = 0; i < (dp->edid.va - 4); i++) { */
-	/* 	int j; */
-	/* 	tcolor = 0x0ff; */
-	/* 	for (j = 0; j < (dp->edid.ha-4); j++) { */
-	/* 		if (j == (dp->edid.ha/2)) { */
-	/* 			tcolor = 0xff00; */
-	/* 		} */
-	/* 		l = (u32*)(graphics + i * dp->stride + j * sizeof(tcolor)); */
-	/* 		memcpy(l,&tcolor,sizeof(tcolor)); */
-	/* 	} */
-	/* }	 */
+	test_gfx(dp);
 
 	set_vbe_mode_info_valid(&dp->edid, graphics);
 	i915_init_done = 1;
-	//io_i915_write32( 0x80000000,BLC_PWM_CPU_CTL2);
-	//io_i915_write32( 0x80000000,BLC_PWM_PCH_CTL1);
 	return i915_init_done;
 
 fail:
 	printk(BIOS_SPEW, "Graphics could not be started;");
 	if (0 && must_cycle_power){
 		printk(BIOS_SPEW, "Turn off power and wait ...");
-		io_i915_write32(0xabcd0000, PCH_PP_CONTROL);
+		gtt_write(PCH_PP_CONTROL,0xabcd0000);
 		udelay(600000);
-		io_i915_write32(0xabcd000f, PCH_PP_CONTROL);
+		gtt_write(PCH_PP_CONTROL,0xabcd000f);
 	}
 	printk(BIOS_SPEW, "Returning.\n");
 	return 0;
diff --git a/src/mainboard/google/slippy/i915io.c b/src/mainboard/google/slippy/i915io.c
index 0801122355..7fbffb6616 100644
--- a/src/mainboard/google/slippy/i915io.c
+++ b/src/mainboard/google/slippy/i915io.c
@@ -47,34 +47,17 @@ void runio(struct intel_dp *dp)
 	/* vbios spins at this point. Some haswell weirdness? */
 	intel_dp_wait_panel_power_control(0xabcd0008);
 
-	/* This is stuff we don't totally understand yet. */
-	io_i915_write32(0x03a903a9,BLC_PWM_CPU_CTL);
-	io_i915_write32(0x03a903a9,BLC_PWM_PCH_CTL2);
-	io_i915_write32(0x80000000,BLC_PWM_PCH_CTL1);
-	io_i915_write32(0x00ffffff,0x64ea8);
-	io_i915_write32(0x00040006,0x64eac);
-	io_i915_write32( PORTD_HOTPLUG_ENABLE | PORTB_HOTPLUG_ENABLE |0x10100010,SDEISR+0x30);
-	io_i915_write32(0x80000000,0x45400);
-	intel_dp_wait_reg(0x00045400, 0xc0000000);
-	io_i915_write32(0x8000298e,CPU_VGACNTRL);
-	io_i915_write32(0x00000000,_CURACNTR);
-	io_i915_write32(0x00000000,_CURABASE);
-	io_i915_write32((/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x00000000,_DSPACNTR);
-	io_i915_write32(0x00000000,_DSPASIZE+0xc);
-	io_i915_write32(0x00000000,_CURBCNTR_IVB);
-	io_i915_write32(0x00000000,_CURBBASE_IVB);
-	io_i915_write32(0x00000000,_DSPBCNTR);
-	io_i915_write32(0x00000000,_DSPBSURF);
-	io_i915_write32(0x00000000,0x72080);
-	io_i915_write32(0x00000000,0x72084);
-	io_i915_write32(0x00000000,_DVSACNTR);
-	io_i915_write32(0x00000000,_DVSASURF);
-	io_i915_write32(0x00008000,DEIIR);
-	intel_dp_wait_reg(0x00044008, 0x00000000);
-	io_i915_write32(0x8020298e,CPU_VGACNTRL);
-	io_i915_write32(/*0x00000800*/dp->stride,_DSPASTRIDE);
-	io_i915_write32(0x00000000,_DSPAADDR);
-	io_i915_write32(0x00000000,_DSPASIZE+0xc);
+	/* This should be a function like intel_panel_enable_backlight
+	   However, we are not sure how the value 0x3a9 comes up.
+	   It has to do something with PWM frequency */
+	gtt_write(BLC_PWM_CPU_CTL,0x03a903a9);
+	gtt_write(BLC_PWM_PCH_CTL2,0x03a903a9);
+	gtt_write(BLC_PWM_PCH_CTL1,BLM_PCH_PWM_ENABLE);
+
+	gtt_write(DEIIR,0x00008000);
+	intel_dp_wait_reg(DEIIR, 0x00000000);
+
+	gtt_write(DSPSTRIDE(dp->plane),dp->stride);
 
 	intel_dp_sink_dpms(dp, 0);
 
@@ -83,25 +66,18 @@ void runio(struct intel_dp *dp)
 	intel_dp_set_m_n_regs(dp);
 
 	intel_dp_set_resolution(dp);
-	io_i915_write32(dp->pipesrc,PIPESRC(dp->pipe));
-	io_i915_write32(0x00000000, PIPECONF(dp->transcoder));
-	io_i915_write32(0x00000000, PCH_TRANSCONF(dp->pipe));
-
-	io_i915_write32(0x20000000,PORT_CLK_SEL_A);
-	io_i915_write32((/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x14000000,_DSPACNTR);
-	io_i915_write32(dp->stride,_DSPASTRIDE);
-
-	io_i915_write32(0x00000000,_DSPAADDR);
-	io_i915_write32(0x00000000,_DSPASIZE+0xc);
-	io_i915_write32((/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x94000000,_DSPACNTR);
-	io_i915_write32((/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x94000000,_DSPACNTR);
-	io_i915_write32(0x00000000,_DSPASIZE+0xc);
-	io_i915_write32(0x00000080,DEIIR);
-
-	io_i915_write32(0x00230000,TRANS_DDI_FUNC_CTL_EDP);
-	io_i915_write32(0x00000010,0x7f008);
-	io_i915_write32(dp->flags,TRANS_DDI_FUNC_CTL_EDP);
-	io_i915_write32(0x80000010,0x7f008);
+
+	gtt_write(PIPESRC(dp->pipe),dp->pipesrc);
+	gtt_write(PIPECONF(dp->transcoder),0x00000000);
+	gtt_write(PCH_TRANSCONF(dp->pipe),0x00000000);
+
+	gtt_write(PORT_CLK_SEL(dp->port),PORT_CLK_SEL_LCPLL_1350);
+	gtt_write(DSPSTRIDE(dp->plane),dp->stride);
+	gtt_write(DSPCNTR(dp->plane),DISPLAY_PLANE_ENABLE|DISPPLANE_RGBX888);
+	gtt_write(DEIIR,0x00000080);
+
+	gtt_write(TRANS_DDI_FUNC_CTL_EDP,dp->flags);
+	gtt_write(PIPECONF(dp->transcoder),PIPECONF_ENABLE|PIPECONF_DITHER_EN);
 
 	intel_dp_wait_panel_power_control(0xabcd000a);
 
@@ -114,14 +90,13 @@ void runio(struct intel_dp *dp)
 	intel_dp_i2c_read(dp, &read_val);
 
 	/* this needs to be a call to a function */
-	io_i915_write32( DP_LINK_TRAIN_PAT_1 | DP_LINK_TRAIN_PAT_1_CPT | DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0 | DP_PORT_WIDTH_1 | DP_PLL_FREQ_270MHZ | DP_SCRAMBLING_DISABLE_IRONLAKE | DP_SYNC_VS_HIGH |0x00000091,DP_A);
-	io_i915_write32(0x00000001,TRANS_DDI_FUNC_CTL_EDP+0x10);
-	io_i915_write32(0x80040011,DP_TP_CTL_A);
-	io_i915_write32( DP_PORT_EN | DP_LINK_TRAIN_PAT_1 | DP_LINK_TRAIN_PAT_1_CPT | DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0 | DP_PORT_WIDTH_1 | DP_ENHANCED_FRAMING | DP_PLL_FREQ_270MHZ | DP_SCRAMBLING_DISABLE_IRONLAKE | DP_SYNC_VS_HIGH |0x80040091,DP_A);
+	gtt_write(DP_A, DP_LINK_TRAIN_PAT_1 | DP_LINK_TRAIN_PAT_1_CPT | DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0 | DP_PORT_WIDTH_1 | DP_PLL_FREQ_270MHZ | DP_SCRAMBLING_DISABLE_IRONLAKE | DP_SYNC_VS_HIGH |0x00000091);
+	gtt_write(DP_TP_CTL(dp->port),DP_TP_CTL_ENABLE | DP_TP_CTL_ENHANCED_FRAME_ENABLE);
+	gtt_write(DP_A, DP_PORT_EN | DP_LINK_TRAIN_PAT_1 | DP_LINK_TRAIN_PAT_1_CPT | DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0 | DP_PORT_WIDTH_1 | DP_ENHANCED_FRAMING | DP_PLL_FREQ_270MHZ | DP_SCRAMBLING_DISABLE_IRONLAKE | DP_SYNC_VS_HIGH |0x80040091);
 
 	/* we may need to move these *after* power well power up and *before* PCH_PP_CONTROL in gma.c */
-	io_i915_write32( PANEL_PORT_SELECT_LVDS |(/* PANEL_POWER_UP_DELAY_MASK */0x1<<16)|(/* PANEL_LIGHT_ON_DELAY_MASK */0xa<<0)|0x0001000a,PCH_PP_ON_DELAYS);
-	io_i915_write32( PANEL_PORT_SELECT_LVDS |(/* PANEL_POWER_UP_DELAY_MASK */0x7d0<<16)|(/* PANEL_LIGHT_ON_DELAY_MASK */0xa<<0)|0x07d0000a,PCH_PP_ON_DELAYS);
+	gtt_write(PCH_PP_ON_DELAYS, PANEL_PORT_SELECT_LVDS |(/* PANEL_POWER_UP_DELAY_MASK */0x1<<16)|(/* PANEL_LIGHT_ON_DELAY_MASK */0xa<<0)|0x0001000a);
+	gtt_write(PCH_PP_ON_DELAYS, PANEL_PORT_SELECT_LVDS |(/* PANEL_POWER_UP_DELAY_MASK */0x7d0<<16)|(/* PANEL_LIGHT_ON_DELAY_MASK */0xa<<0)|0x07d0000a);
 
 	intel_dp_set_bw(dp);
 	intel_dp_set_lane_count(dp);
@@ -129,69 +104,33 @@ void runio(struct intel_dp *dp)
 	mainboard_train_link(dp);
 
 	/* need a function: intel_ddi_set_tp or similar */
-	io_i915_write32(0x80040200,DP_TP_CTL_A);
-	io_i915_write32(0x80040300,DP_TP_CTL_A);
-	io_i915_write32(0x03a903a9,BLC_PWM_CPU_CTL);
-	io_i915_write32(0x03a903a9,BLC_PWM_PCH_CTL2);
-	io_i915_write32(0x80000000,BLC_PWM_PCH_CTL1);
+	gtt_write(DP_TP_CTL(dp->port),DP_TP_CTL_ENABLE | DP_TP_CTL_ENHANCED_FRAME_ENABLE | DP_TP_CTL_LINK_TRAIN_IDLE);
+	gtt_write(DP_TP_CTL(dp->port),DP_TP_CTL_ENABLE | DP_TP_CTL_ENHANCED_FRAME_ENABLE | DP_TP_CTL_LINK_TRAIN_NORMAL);
+
+	gtt_write(BLC_PWM_CPU_CTL,0x03a903a9);
+	gtt_write(BLC_PWM_PCH_CTL2,0x03a903a9);
+	gtt_write(BLC_PWM_PCH_CTL1,0x80000000);
 
 	/* some of this is not needed. */
-	io_i915_write32( PORTD_HOTPLUG_ENABLE | PORTB_HOTPLUG_ENABLE |0x10100010,SDEISR+0x30);
-	io_i915_write32( DIGITAL_PORTA_HOTPLUG_ENABLE |0x00000010,DIGITAL_PORT_HOTPLUG_CNTRL);
-	io_i915_write32(0x00000000,SDEIIR);
-	io_i915_write32(0x00000000,SDEIIR);
-	io_i915_write32(0x00000000,DEIIR);
-	io_i915_write32(0x80000000,0x45400);
-	intel_dp_wait_reg(0x00045400, 0xc0000000);
-	io_i915_write32(0x80000000,0x45400);
-	intel_dp_wait_reg(0x00045400, 0xc0000000);
-	printk(BIOS_SPEW, "pci dev(0x0,0x2,0x0,0x6)");
-	io_i915_write32(0x80000000,0x45400);
-	intel_dp_wait_reg(0x00045400, 0xc0000000);
-	io_i915_write32(0x8000298e,CPU_VGACNTRL);
-	io_i915_write32(0x00000000,_CURACNTR);
-	io_i915_write32(0x00000000,_CURABASE);
-	io_i915_write32((/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x00000000,_DSPACNTR);
-	io_i915_write32(0x00000000,_DSPASIZE+0xc);
-	io_i915_write32(0x00000000,_CURBCNTR_IVB);
-	io_i915_write32(0x00000000,_CURBBASE_IVB);
-	io_i915_write32(0x00000000,_DSPBCNTR);
-	io_i915_write32(0x00000000,_DSPBSURF);
-	io_i915_write32(0x00000000,0x72080);
-	io_i915_write32(0x00000000,0x72084);
-	io_i915_write32(0x00000000,_DVSACNTR);
-	io_i915_write32(0x00000000,_DVSASURF);
-	io_i915_write32(0x00008000,DEIIR);
-	intel_dp_wait_reg(0x00044008, 0x00000000);
-
-	/* we just turned vdd off. We're not going to wait. The panel is up. */
-	io_i915_write32(0x8020298e,CPU_VGACNTRL);
-	io_i915_write32(/*0x00000640*/dp->stride,_DSPASTRIDE);
-	io_i915_write32(0x00000000,_DSPAADDR);
-	io_i915_write32(0x00000000,_DSPASIZE+0xc);
-	io_i915_write32((/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x00000000,_DSPACNTR);
-	io_i915_write32(0x00000000,_DSPASIZE+0xc);
-	/* io_i915_write32(dp->pfa_pos,_PFA_WIN_POS); */
-	/* io_i915_write32(0x00000000,_PFA_WIN_SZ); */
-	io_i915_write32(dp->pipesrc,_PIPEASRC);
-	/* io_i915_write32(dp->pfa_pos,_PFA_WIN_POS); */
-	/* io_i915_write32(dp->pfa_ctl,_PFA_CTL_1); */
-	/* io_i915_write32(dp->pfa_sz,_PFA_WIN_SZ); */
-	io_i915_write32(0x00000080,DEIIR);
-	intel_dp_wait_reg(0x00044008, 0x00000000);
-	io_i915_write32((/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x14000000,_DSPACNTR);
-	io_i915_write32(/*0x00000640*/dp->stride,_DSPASTRIDE);
-	io_i915_write32(0x00000000,_DSPAADDR);
-	io_i915_write32(0x00000000,_DSPASIZE+0xc);
-	io_i915_write32((/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x94000000,_DSPACNTR);
-	io_i915_write32((/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x98000000,_DSPACNTR);
-	io_i915_write32(0x00000000,_DSPASIZE+0xc);
-
-	io_i915_write32( EDP_BLC_ENABLE | PANEL_POWER_RESET | PANEL_POWER_ON |0x00000007,PCH_PP_CONTROL);
-
-	io_i915_write32( PORTD_HOTPLUG_ENABLE | PORTB_HOTPLUG_ENABLE |0x10100010,SDEISR+0x30);
-	io_i915_write32( DIGITAL_PORTA_HOTPLUG_ENABLE |0x00000010,DIGITAL_PORT_HOTPLUG_CNTRL);
-	io_i915_write32(0x00000000,SDEIIR);
-	io_i915_write32(0x00000000,SDEIIR);
-	io_i915_write32(0x00000000,DEIIR);
+	gtt_write(DIGITAL_PORT_HOTPLUG_CNTRL, DIGITAL_PORTA_HOTPLUG_ENABLE );
+
+	gtt_write(SDEIIR,0x00000000);
+	gtt_write(DEIIR,0x00000000);
+	gtt_write(DEIIR,0x00008000);
+	intel_dp_wait_reg(DEIIR, 0x00000000);
+
+	gtt_write(DSPSTRIDE(dp->plane),dp->stride);
+	gtt_write(PIPESRC(dp->pipe),dp->pipesrc);
+
+	gtt_write(DEIIR,0x00000080);
+	intel_dp_wait_reg(DEIIR, 0x00000000);
+
+	gtt_write(DSPSTRIDE(dp->plane),dp->stride);
+	gtt_write(DSPCNTR(dp->plane),DISPLAY_PLANE_ENABLE | DISPPLANE_RGBX888);
+
+	gtt_write(PCH_PP_CONTROL,EDP_BLC_ENABLE | PANEL_POWER_RESET | PANEL_POWER_ON);
+
+	gtt_write(SDEIIR,0x00000000);
+	gtt_write(SDEIIR,0x00000000);
+	gtt_write(DEIIR,0x00000000);
 }
diff --git a/src/northbridge/intel/haswell/Kconfig b/src/northbridge/intel/haswell/Kconfig
index e06db75d5b..44ee71877d 100644
--- a/src/northbridge/intel/haswell/Kconfig
+++ b/src/northbridge/intel/haswell/Kconfig
@@ -24,6 +24,8 @@ config NORTHBRIDGE_INTEL_HASWELL
 	select REQUIRES_BLOB
 	select MMCONF_SUPPORT
 	select MMCONF_SUPPORT_DEFAULT
+	select INTEL_DDI
+	select INTEL_DP
 
 if NORTHBRIDGE_INTEL_HASWELL
 
diff --git a/src/northbridge/intel/haswell/gma.c b/src/northbridge/intel/haswell/gma.c
index ee447bfc95..9dfba9a316 100644
--- a/src/northbridge/intel/haswell/gma.c
+++ b/src/northbridge/intel/haswell/gma.c
@@ -25,7 +25,9 @@
 #include <device/pci.h>
 #include <device/pci_ids.h>
 #include <drivers/intel/gma/i915_reg.h>
+#include <drivers/intel/gma/i915.h>
 #include <cpu/intel/haswell/haswell.h>
+#include <stdlib.h>
 
 #include "chip.h"
 #include "haswell.h"
@@ -126,12 +128,12 @@ u32 map_oprom_vendev(u32 vendev)
 
 static struct resource *gtt_res = NULL;
 
-static inline u32 gtt_read(u32 reg)
+u32 gtt_read(u32 reg)
 {
 	return read32(gtt_res->base + reg);
 }
 
-static inline void gtt_write(u32 reg, u32 data)
+void gtt_write(u32 reg, u32 data)
 {
 	write32(gtt_res->base + reg, data);
 }
@@ -209,7 +211,10 @@ static void gma_pm_init_pre_vbios(struct device *dev)
 	gtt_poll(0x138124, (1 << 31), (0 << 31));
 
 	/* Enable PM Interrupts */
-	gtt_write(0x4402c, 0x03000076);
+	gtt_write(GEN6_PMIER, GEN6_PM_MBOX_EVENT | GEN6_PM_THERMAL_EVENT |
+		  GEN6_PM_RP_DOWN_TIMEOUT | GEN6_PM_RP_UP_THRESHOLD |
+		  GEN6_PM_RP_DOWN_THRESHOLD | GEN6_PM_RP_UP_EI_EXPIRED |
+		  GEN6_PM_RP_DOWN_EI_EXPIRED);
 
 	/* Enable RC6 in idle */
 	gtt_write(0x0a094, 0x00040000);
@@ -218,6 +223,26 @@ static void gma_pm_init_pre_vbios(struct device *dev)
 	gtt_write_regs(haswell_gt_lock);
 }
 
+static void init_display_planes(void)
+{
+	int pipe, plane;
+
+	/* Disable cursor mode */
+	for (pipe = PIPE_A; pipe <= PIPE_C; pipe++) {
+		gtt_write(CURCNTR_IVB(pipe), CURSOR_MODE_DISABLE);
+		gtt_write(CURBASE_IVB(pipe), 0x00000000);
+	}
+
+	/* Disable primary plane and set surface base address*/
+	for (plane = PLANE_A; plane <= PLANE_C; plane++) {
+		gtt_write(DSPCNTR(plane), DISPLAY_PLANE_DISABLE);
+		gtt_write(DSPSURF(plane), 0x00000000);
+	}
+
+	/* Disable VGA display */
+	gtt_write(CPU_VGACNTRL, CPU_VGA_DISABLE);
+}
+
 static void gma_setup_panel(struct device *dev)
 {
 	struct northbridge_intel_haswell_config *conf = dev->chip_info;
@@ -226,122 +251,90 @@ static void gma_setup_panel(struct device *dev)
 	printk(BIOS_DEBUG, "GT Power Management Init (post VBIOS)\n");
 
 	/* Setup Digital Port Hotplug */
-	reg32 = gtt_read(0xc4030);
+	reg32 = gtt_read(PCH_PORT_HOTPLUG);
 	if (!reg32) {
 		reg32 = (conf->gpu_dp_b_hotplug & 0x7) << 2;
 		reg32 |= (conf->gpu_dp_c_hotplug & 0x7) << 10;
 		reg32 |= (conf->gpu_dp_d_hotplug & 0x7) << 18;
-		gtt_write(0xc4030, reg32);
+		gtt_write(PCH_PORT_HOTPLUG, reg32);
 	}
 
 	/* Setup Panel Power On Delays */
-	reg32 = gtt_read(0xc7208);
+	reg32 = gtt_read(PCH_PP_ON_DELAYS);
 	if (!reg32) {
 		reg32 = (conf->gpu_panel_port_select & 0x3) << 30;
 		reg32 |= (conf->gpu_panel_power_up_delay & 0x1fff) << 16;
 		reg32 |= (conf->gpu_panel_power_backlight_on_delay & 0x1fff);
-		gtt_write(0xc7208, reg32);
+		gtt_write(PCH_PP_ON_DELAYS, reg32);
 	}
 
 	/* Setup Panel Power Off Delays */
-	reg32 = gtt_read(0xc720c);
+	reg32 = gtt_read(PCH_PP_OFF_DELAYS);
 	if (!reg32) {
 		reg32 = (conf->gpu_panel_power_down_delay & 0x1fff) << 16;
 		reg32 |= (conf->gpu_panel_power_backlight_off_delay & 0x1fff);
-		gtt_write(0xc720c, reg32);
+		gtt_write(PCH_PP_OFF_DELAYS, reg32);
 	}
 
 	/* Setup Panel Power Cycle Delay */
 	if (conf->gpu_panel_power_cycle_delay) {
-		reg32 = gtt_read(0xc7210);
+		reg32 = gtt_read(PCH_PP_DIVISOR);
 		reg32 &= ~0xff;
 		reg32 |= conf->gpu_panel_power_cycle_delay & 0xff;
-		gtt_write(0xc7210, reg32);
+		gtt_write(PCH_PP_DIVISOR, reg32);
 	}
 
 	/* Enable Backlight if needed */
 	if (conf->gpu_cpu_backlight) {
-		gtt_write(0x48250, (1 << 31));
-		gtt_write(0x48254, conf->gpu_cpu_backlight);
+		gtt_write(BLC_PWM_CPU_CTL2, BLC_PWM2_ENABLE);
+		gtt_write(BLC_PWM_CPU_CTL, conf->gpu_cpu_backlight);
 	}
 	if (conf->gpu_pch_backlight) {
-		gtt_write(0xc8250, (1 << 31));
-		gtt_write(0xc8254, conf->gpu_pch_backlight);
+		gtt_write(BLC_PWM_PCH_CTL1, BLM_PCH_PWM_ENABLE);
+		gtt_write(BLC_PWM_PCH_CTL2, conf->gpu_pch_backlight);
 	}
 
 	/* Get display,pipeline,and DDI registers into a basic sane state */
-	/* not all these have documented names. */
-	gtt_write(0x45400, 0x80000000);
-	gtt_poll( 0x00045400, 0xc0000000, 0xc0000000);
-	gtt_write(_CURACNTR, 0x00000000);
-	gtt_write(_DSPACNTR, (/* DISPPLANE_SEL_PIPE(0=A,1=B) */0x0<<24)|0x00000000);
-	gtt_write(_DSPBCNTR, 0x00000000);
-	gtt_write(CPU_VGACNTRL, 0x8000298e);
-	gtt_write(_DSPASIZE+0xc, 0x00000000);
-	gtt_write(_DSPBSURF, 0x00000000);
-	gtt_write(0x4f008, 0x00000000);
-	gtt_write(0x4f008, 0x00000000);
-	gtt_write(0x4f008, 0x00000000);
-	gtt_write(0x4f040, 0x01000001);
-	gtt_write(0x4f044, 0x00000000);
-	gtt_write(0x4f048, 0x00000000);
-	gtt_write(0x4f04c, 0x03030000);
-	gtt_write(0x4f050, 0x00000000);
-	gtt_write(0x4f054, 0x00000001);
-	gtt_write(0x4f058, 0x00000000);
-	gtt_write(0x4f04c, 0x03450000);
-	gtt_write(0x4f04c, 0x45450000);
-	gtt_write(0x4f000, 0x03000400);
-	gtt_write(DP_A, 0x00000091); /* DDI-A enable */
+	power_well_enable();
+
+	init_display_planes();
+
+	/* DDI-A params set:
+	   bit 0: Display detected (RO)
+	   bit 4: DDI A supports 4 lanes and DDI E is not used
+	   bit 7: DDI buffer is idle
+	*/
+	gtt_write(DDI_BUF_CTL_A, DDI_BUF_IS_IDLE | DDI_A_4_LANES | DDI_INIT_DISPLAY_DETECTED);
+
+	/* Set FDI registers - is this required? */
 	gtt_write(_FDI_RXA_MISC, 0x00200090);
 	gtt_write(_FDI_RXA_MISC, 0x0a000000);
-	gtt_write(0x46408, 0x00000070);
+
+	/* Enable the handshake with PCH display when processing reset */
+	gtt_write(NDE_RSTWRN_OPT, RST_PCH_HNDSHK_EN);
+
+	/* undocumented */
 	gtt_write(0x42090, 0x04000000);
-	gtt_write(0x4f050, 0xc0000000);
 	gtt_write(0x9840, 0x00000000);
 	gtt_write(0x42090, 0xa4000000);
-	gtt_write(SOUTH_DSPCLK_GATE_D, 0x00001000);
+
+	gtt_write(SOUTH_DSPCLK_GATE_D, PCH_LP_PARTITION_LEVEL_DISABLE);
+
+	/* undocumented */
 	gtt_write(0x42080, 0x00004000);
-	gtt_write(0x64f80, 0x00ffffff);
-	gtt_write(0x64f84, 0x0007000e);
-	gtt_write(0x64f88, 0x00d75fff);
-	gtt_write(0x64f8c, 0x000f000a);
-	gtt_write(0x64f90, 0x00c30fff);
-	gtt_write(0x64f94, 0x00060006);
-	gtt_write(0x64f98, 0x00aaafff);
-	gtt_write(0x64f9c, 0x001e0000);
-	gtt_write(0x64fa0, 0x00ffffff);
-	gtt_write(0x64fa4, 0x000f000a);
-	gtt_write(0x64fa8, 0x00d75fff);
-	gtt_write(0x64fac, 0x00160004);
-	gtt_write(0x64fb0, 0x00c30fff);
-	gtt_write(0x64fb4, 0x001e0000);
-	gtt_write(0x64fb8, 0x00ffffff);
-	gtt_write(0x64fbc, 0x00060006);
-	gtt_write(0x64fc0, 0x00d75fff);
-	gtt_write(0x64fc4, 0x001e0000);
-	gtt_write(DDI_BUF_TRANS_A, 0x00ffffff);
-	gtt_write(DDI_BUF_TRANS_A+0x4, 0x0006000e);
-	gtt_write(DDI_BUF_TRANS_A+0x8, 0x00d75fff);
-	gtt_write(DDI_BUF_TRANS_A+0xc, 0x0005000a);
-	gtt_write(DDI_BUF_TRANS_A+0x10, 0x00c30fff);
-	gtt_write(DDI_BUF_TRANS_A+0x14, 0x00040006);
-	gtt_write(DDI_BUF_TRANS_A+0x18, 0x80aaafff);
-	gtt_write(DDI_BUF_TRANS_A+0x1c, 0x000b0000);
-	gtt_write(DDI_BUF_TRANS_A+0x20, 0x00ffffff);
-	gtt_write(DDI_BUF_TRANS_A+0x24, 0x0005000a);
-	gtt_write(DDI_BUF_TRANS_A+0x28, 0x00d75fff);
-	gtt_write(DDI_BUF_TRANS_A+0x2c, 0x000c0004);
-	gtt_write(DDI_BUF_TRANS_A+0x30, 0x80c30fff);
-	gtt_write(DDI_BUF_TRANS_A+0x34, 0x000b0000);
-	gtt_write(DDI_BUF_TRANS_A+0x38, 0x00ffffff);
-	gtt_write(DDI_BUF_TRANS_A+0x3c, 0x00040006);
-	gtt_write(DDI_BUF_TRANS_A+0x40, 0x80d75fff);
-	gtt_write(DDI_BUF_TRANS_A+0x44, 0x000b0000);
-	gtt_write(DIGITAL_PORT_HOTPLUG_CNTRL,
-		DIGITAL_PORTA_HOTPLUG_ENABLE |0x00000010);
-	gtt_write(SDEISR+0x30,
-		PORTD_HOTPLUG_ENABLE | PORTB_HOTPLUG_ENABLE |0x10100010);
+
+	/* Prepare DDI buffers for DP and FDI */
+	intel_prepare_ddi();
+
+	/* Hot plug detect buffer enabled for port A */
+	gtt_write(DIGITAL_PORT_HOTPLUG_CNTRL, DIGITAL_PORTA_HOTPLUG_ENABLE);
+
+	/* Enable HPD buffer for digital port D and B */
+	gtt_write(PCH_PORT_HOTPLUG, PORTD_HOTPLUG_ENABLE | PORTB_HOTPLUG_ENABLE);
+
+	/* Bits 4:0 - Power cycle delay (default 0x6 --> 500ms)
+	   Bits 31:8 - Reference divider (0x0004af ----> 24MHz)
+	*/
 	gtt_write(PCH_PP_DIVISOR, 0x0004af06);
 }
 
@@ -406,19 +399,16 @@ static void gma_func0_init(struct device *dev)
 
 #if CONFIG_MAINBOARD_DO_NATIVE_VGA_INIT
 	printk(BIOS_SPEW, "NATIVE graphics, run native enable\n");
-	u32 iobase, mmiobase, physbase;
+	u32 mmiobase, physbase;
 	/* Default set to 1 since it might be required for
 	   stuff like seabios */
 	unsigned int init_fb = 1;
-	iobase = dev->resource_list[2].base;
 	mmiobase = dev->resource_list[0].base;
 	physbase = pci_read_config32(dev, 0x5c) & ~0xf;
 #ifdef CONFIG_CHROMEOS
 	init_fb = developer_mode_enabled() || recovery_mode_enabled();
 #endif
-	int i915lightup(unsigned int physbase, unsigned int iobase, unsigned int mmio,
-			unsigned int gfx, unsigned int init_fb);
-	lightup_ok = i915lightup(physbase, iobase, mmiobase, graphics_base, init_fb);
+	lightup_ok = i915lightup(physbase, mmiobase, graphics_base, init_fb);
 	if (lightup_ok)
 		gfx_set_init_done(1);
 #endif
diff --git a/src/northbridge/intel/nehalem/gma.c b/src/northbridge/intel/nehalem/gma.c
index 2470b0f4a0..f76fbc4e15 100644
--- a/src/northbridge/intel/nehalem/gma.c
+++ b/src/northbridge/intel/nehalem/gma.c
@@ -272,12 +272,12 @@ u32 map_oprom_vendev(u32 vendev)
 
 static struct resource *gtt_res = NULL;
 
-static inline u32 gtt_read(u32 reg)
+u32 gtt_read(u32 reg)
 {
 	return read32(gtt_res->base + reg);
 }
 
-static inline void gtt_write(u32 reg, u32 data)
+void gtt_write(u32 reg, u32 data)
 {
 	write32(gtt_res->base + reg, data);
 }
diff --git a/src/northbridge/intel/sandybridge/gma.c b/src/northbridge/intel/sandybridge/gma.c
index 0add055623..f305b81458 100644
--- a/src/northbridge/intel/sandybridge/gma.c
+++ b/src/northbridge/intel/sandybridge/gma.c
@@ -595,7 +595,7 @@ static void gma_func0_init(struct device *dev)
 	physbase = pci_read_config32(dev, 0x5c) & ~0xf;
 	graphics_base = dev->resource_list[1].base;
 
-	int lightup_ok = i915lightup(conf, physbase, iobase, mmiobase, graphics_base);
+	int lightup_ok = i915lightup_sandy(conf, physbase, iobase, mmiobase, graphics_base);
 	if (lightup_ok)
 		gfx_set_init_done(1);
 #endif
diff --git a/src/northbridge/intel/sandybridge/gma.h b/src/northbridge/intel/sandybridge/gma.h
index bc5d986e7a..b7502cda34 100644
--- a/src/northbridge/intel/sandybridge/gma.h
+++ b/src/northbridge/intel/sandybridge/gma.h
@@ -168,5 +168,5 @@ typedef struct {
 
 struct northbridge_intel_sandybridge_config;
 
-int i915lightup(const struct northbridge_intel_sandybridge_config *info,
+int i915lightup_sandy(const struct northbridge_intel_sandybridge_config *info,
 		u32 physbase, u16 pio, u32 mmio, u32 lfb);
diff --git a/src/northbridge/intel/sandybridge/gma_ivybridge_lvds.c b/src/northbridge/intel/sandybridge/gma_ivybridge_lvds.c
index ff877ffcb6..53fbfda3bc 100644
--- a/src/northbridge/intel/sandybridge/gma_ivybridge_lvds.c
+++ b/src/northbridge/intel/sandybridge/gma_ivybridge_lvds.c
@@ -207,7 +207,7 @@ static void enable_port(u32 mmio)
 	read32(mmio + 0xc4000);
 }
 
-int i915lightup(const struct northbridge_intel_sandybridge_config *info,
+int i915lightup_sandy(const struct northbridge_intel_sandybridge_config *info,
 		u32 physbase, u16 piobase, u32 mmio, u32 lfb)
 {
 	int i;