[Intel-gfx] [PATCH 30/49] drm/i915/bxt: add display initialize/uninitialize sequence

Imre Deak imre.deak at intel.com
Tue Mar 17 02:39:56 PDT 2015


From: Vandana Kannan <vandana.kannan at intel.com>

Add display clock/PHY initialization sequence as per BSpec.

Until GOP/VBIOS provides an upper limit value for CDCLK, comparing clock
value with 624 MHz and returning 0 in case it exceeds.

Note that the CD clock and PHY initialization/uninitialization are done
at their current place only for simplicity, in a future patch - when more
of the runtime PM features will be enabled - these will be moved to
power well#1 and modeset encoder enabling/disabling hooks respectively.
This also means that atm dynamic power gating power well #2 is
effectively disabled.

v1: Added function definitions in header files
v2: Imre's review comments addressed
- Moved CDCLK related definitions to i915_reg.h
- Removed defintions for CDCLK frequency
- Split uninit_cdclk() by adding a phy_uninit function
- Calculate freq and decimal based on input frequency
- Program SSA precharge based on input frequency
- Use wait_for 1ms instead 200us udelay for DE PLL locking
- Removed initial value for divider, freq, decimal, ratio.
- Replaced polling loops with wait_for
- Parameterized latency optim setting
- Fix the parts where DE PLL has to be disabled.
- Call CDCLK selection from mode set

v3: (imre)
- add note about the plan to move the cdclk/phy init to a better place
- take rps.hw_lock around pcode access
- fix DDI PHY timeout value
- squash in Vandana's "PORT_CL2CM_DW6_A BUN fix",
  "DDI PHY programming register defn", "Do ddi_phy_init always",
  "Check CDCLK upper limit" patches
- move PHY register macros next to the corresponding CHV/VLV macros
- move DE PLL register macros here from another patch since they are
  used here first
- add BXT_ prefix to CDCLK flags
- s/COMMON_RESET/COMMON_RESET_DIS/ and clarify related code comments
- fix incorrect read value for the RMW of BXT_PHY_CTL_FAMILY_DDI
- fix using GT_DISPLAY_EDP_POWER_ON vs. GT_DISPLAY_DDI_POWER_ON
  when powering on DDI ports
- fix incorrect port when setting BXT_PORT_TX_DW14_LN for DDI ports
- add missing masking when programming CDCLK_FREQ_DECIMAL
- add missing powering on for DDI-C port, rename OCL2_LDOFUSE_PWR_EN
  to OCL2_LDOFUSE_PWR_DIS to reduce confusion
- add note about mismatch with bspec in the PORT_REF_DW6 fields
- factor out PHY init code to a new function, so we can call it for
  PHY_A and PHY_BC, instead of open-coding the same

Signed-off-by: Vandana Kannan <vandana.kannan at intel.com> (v2)
Signed-off-by: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h      | 126 +++++++++++++++
 drivers/gpu/drm/i915/intel_ddi.c     | 291 +++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/intel_display.c |  75 +++++++++
 drivers/gpu/drm/i915/intel_drv.h     |   4 +
 4 files changed, 496 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index b4474d3..a3579c0 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1120,6 +1120,110 @@ enum skl_disp_power_wells {
 #define   DPIO_FRC_LATENCY_SHFIT	8
 #define CHV_TX_DW14(ch, lane) _TXLANE(ch, lane, 0xb8)
 #define   DPIO_UPAR_SHIFT		30
+
+/* BXT PHY registers */
+enum bxt_phy {
+	BXT_PHY_A,
+	BXT_PHY_BC
+};
+
+#define BXT_PHY(phy, a, b)		((a) + (phy) * ((b) - (a)))
+
+#define BXT_P_CR_GT_DISP_PWRON_0_2_0_GTTMMADR	0x138090
+#define   _EDP_POWER_ON				(1 << 1)
+#define   _DDI_POWER_ON				(1 << 0)
+#define   GT_DISPLAY_POWER_ON(phy)		BXT_PHY(phy, _EDP_POWER_ON, \
+							_DDI_POWER_ON)
+
+#define _PHY_CTL_FAMILY_EDP		0x64C80
+#define _PHY_CTL_FAMILY_DDI		0x64C90
+#define   COMMON_RESET_DIS		(1 << 31)
+#define BXT_PHY_CTL_FAMILY(phy)		BXT_PHY(phy, _PHY_CTL_FAMILY_EDP, \
+						     _PHY_CTL_FAMILY_DDI)
+
+/* BXT PHY common lane registers */
+#define _PORT_CL1CM_DW0_A		0x162000
+#define _PORT_CL1CM_DW0_BC		0x6C000
+#define   PHY_POWER_GOOD		(1 << 16)
+#define BXT_PORT_CL1CM_DW0(phy)		BXT_PHY(phy, _PORT_CL1CM_DW0_A,	\
+						     _PORT_CL1CM_DW0_BC)
+
+#define _PORT_CL1CM_DW9_A		0x162024
+#define _PORT_CL1CM_DW9_BC		0x6C024
+#define   IREF0RC_OFFSET_SHIFT		8
+#define   IREF0RC_OFFSET_MASK		(0xFF << IREF0RC_OFFSET_SHIFT)
+#define BXT_PORT_CL1CM_DW9(phy)		BXT_PHY(phy, _PORT_CL1CM_DW9_A,	\
+						     _PORT_CL1CM_DW9_BC)
+
+#define _PORT_CL1CM_DW10_A		0x162028
+#define _PORT_CL1CM_DW10_BC		0x6C028
+#define   IREF1RC_OFFSET_SHIFT		8
+#define   IREF1RC_OFFSET_MASK		(0xFF << IREF1RC_OFFSET_SHIFT)
+#define BXT_PORT_CL1CM_DW10(phy)	BXT_PHY(phy, _PORT_CL1CM_DW10_A, \
+						     _PORT_CL1CM_DW10_BC)
+
+#define _PORT_CL1CM_DW28_A		0x162070
+#define _PORT_CL1CM_DW28_BC		0x6C070
+#define   OCL1_POWER_DOWN_EN		(1 << 23)
+#define   DW28_OLDO_DYN_PWR_DOWN_EN	(1 << 22)
+#define   SUS_CLK_CONFIG		0x3
+#define BXT_PORT_CL1CM_DW28(phy)	BXT_PHY(phy, _PORT_CL1CM_DW28_A, \
+						     _PORT_CL1CM_DW28_BC)
+
+#define _PORT_CL1CM_DW30_A		0x162078
+#define _PORT_CL1CM_DW30_BC		0x6C078
+#define   OCL2_LDOFUSE_PWR_DIS		(1 << 6)
+#define BXT_PORT_CL1CM_DW30(phy)	BXT_PHY(phy, _PORT_CL1CM_DW30_A, \
+						     _PORT_CL1CM_DW30_BC)
+
+/* Defined for PHY_BC only */
+#define BXT_PORT_CL2CM_DW6_BC		0x6C358
+#define   DW6_OLDO_DYN_PWR_DOWN_EN	(1 << 28)
+
+/* BXT PHY Ref registers */
+#define _PORT_REF_DW3_A			0x16218C
+#define _PORT_REF_DW3_BC		0x6C18C
+#define   GRC_DONE			(1 << 22)
+#define BXT_PORT_REF_DW3(phy)		BXT_PHY(phy, _PORT_REF_DW3_A,	\
+						     _PORT_REF_DW3_BC)
+
+#define _PORT_REF_DW6_A			0x162198
+#define _PORT_REF_DW6_BC		0x6C198
+/*
+ * FIXME: BSpec disagrees on the following two fields, check them with
+ * HW/documentation people.
+ */
+#define   GRC_CODE_SHIFT		23
+#define   GRC_CODE_MASK			(0x1FF << GRC_CODE_SHIFT)
+#define   GRC_CODE_FAST_SHIFT		16
+#define   GRC_CODE_FAST_MASK		(0x7F << GRC_CODE_FAST_SHIFT)
+#define   GRC_CODE_SLOW_SHIFT		8
+#define   GRC_CODE_SLOW_MASK		(0xFF << GRC_CODE_SLOW_SHIFT)
+#define   GRC_CODE_NOM_MASK		0xFF
+#define BXT_PORT_REF_DW6(phy)		BXT_PHY(phy, _PORT_REF_DW6_A,	\
+						     _PORT_REF_DW6_BC)
+
+#define _PORT_REF_DW8_A			0x1621A0
+#define _PORT_REF_DW8_BC		0x6C1A0
+#define   GRC_DIS			(1 << 15)
+#define   GRC_RDY_OVRD			(1 << 1)
+#define BXT_PORT_REF_DW8(phy)		BXT_PHY(phy, _PORT_REF_DW8_A,	\
+						     _PORT_REF_DW8_BC)
+
+/* BXT PHY TX registers */
+#define BXT_LANE_OFFSET(lane)           (((lane) >> 1) * 0x200 +	\
+					 ((lane) & 1) * 0x80)
+
+#define _PORT_TX_DW14_LN0_A		0x162538
+#define _PORT_TX_DW14_LN0_B		0x6C538
+#define _PORT_TX_DW14_LN0_C		0x6C938
+#define   LATENCY_OPTIM_SHIFT		30
+#define   LATENCY_OPTIM			(1 << LATENCY_OPTIM_SHIFT)
+#define BXT_PORT_TX_DW14_LN(port, lane)	(_PORT3(port, _PORT_TX_DW14_LN0_A,   \
+						      _PORT_TX_DW14_LN0_B,   \
+						      _PORT_TX_DW14_LN0_C) + \
+					 BXT_LANE_OFFSET(lane))
+
 /*
  * Fence registers
  */
@@ -5326,6 +5430,9 @@ enum skl_disp_power_wells {
 #define  DISP_FBC_WM_DIS		(1<<15)
 #define DISP_ARB_CTL2	0x45004
 #define  DISP_DATA_PARTITION_5_6	(1<<6)
+#define DBUF_CTL	0x45008
+#define  DBUF_POWER_REQUEST		(1<<31)
+#define  DBUF_POWER_STATE		(1<<30)
 #define GEN7_MSG_CTL	0x45010
 #define  WAIT_FOR_PCH_RESET_ACK		(1<<1)
 #define  WAIT_FOR_PCH_FLR_ACK		(1<<0)
@@ -6271,6 +6378,7 @@ enum skl_disp_power_wells {
 #define   GEN6_PCODE_WRITE_D_COMP		0x11
 #define   GEN6_ENCODE_RC6_VID(mv)		(((mv) - 245) / 5)
 #define   GEN6_DECODE_RC6_VID(vids)		(((vids) * 5) + 245)
+#define   DISPLAY_PCU_CONTROL			0x17
 #define   DISPLAY_IPS_CONTROL			0x19
 #define	  HSW_PCODE_DYNAMIC_DUTY_CYCLE_CONTROL	0x1A
 #define GEN6_PCODE_DATA				0x138128
@@ -6748,6 +6856,13 @@ enum skl_disp_power_wells {
 #define  CDCLK_FREQ_675_617		(3<<26)
 #define  CDCLK_FREQ_DECIMAL_MASK	(0x7ff)
 
+#define  BXT_CDCLK_CD2X_DIV_SEL_MASK	(3<<22)
+#define  BXT_CDCLK_CD2X_DIV_SEL_1	(0<<22)
+#define  BXT_CDCLK_CD2X_DIV_SEL_1_5	(1<<22)
+#define  BXT_CDCLK_CD2X_DIV_SEL_2	(2<<22)
+#define  BXT_CDCLK_CD2X_DIV_SEL_4	(3<<22)
+#define  BXT_CDCLK_SSA_PRECHARGE_ENABLE	(1<<16)
+
 /* LCPLL_CTL */
 #define LCPLL1_CTL		0x46010
 #define LCPLL2_CTL		0x46014
@@ -6812,6 +6927,17 @@ enum skl_disp_power_wells {
 #define GET_CFG_CR1_REG(id) (DPLL1_CFGCR1 + (id - SKL_DPLL1) * 8)
 #define GET_CFG_CR2_REG(id) (DPLL1_CFGCR2 + (id - SKL_DPLL1) * 8)
 
+/* BXT display engine PLL */
+#define BXT_DE_PLL_CTL			0x6d000
+#define   BXT_DE_PLL_RATIO_1152		0x3c
+#define   BXT_DE_PLL_RATIO_1248		0x41
+#define   BXT_DE_PLL_RATIO_DEFAULT	0x64
+#define   BXT_DE_PLL_RATIO_MASK		0x7f
+
+#define BXT_DE_PLL_ENABLE		0x46070
+#define   BXT_DE_PLL_PLL_ENABLE		(1 << 31)
+#define   BXT_DE_PLL_LOCK		(1 << 30)
+
 /* Please see hsw_read_dcomp() and hsw_write_dcomp() before using this register,
  * since on HSW we can't write to it using I915_WRITE. */
 #define D_COMP_HSW			(MCHBAR_MIRROR_BASE_SNB + 0x5F0C)
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index a203d9d..789682d 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -1957,6 +1957,294 @@ static void skl_shared_dplls_init(struct drm_i915_private *dev_priv)
 	}
 }
 
+static void bxt_init_phy(struct drm_i915_private *dev_priv, enum bxt_phy phy)
+{
+	enum port port;
+	uint32_t val;
+
+	val = I915_READ(BXT_P_CR_GT_DISP_PWRON_0_2_0_GTTMMADR);
+	val |= GT_DISPLAY_POWER_ON(phy);
+	I915_WRITE(BXT_P_CR_GT_DISP_PWRON_0_2_0_GTTMMADR, val);
+
+	/* Considering 10ms timeout until BSpec is updated */
+	if (wait_for(I915_READ(BXT_PORT_CL1CM_DW0(phy)) & PHY_POWER_GOOD, 10))
+		DRM_ERROR("timeout during PHY#%d power on\n", phy);
+
+	/* Program latency optim setting */
+	for (port =  (phy == BXT_PHY_A ? PORT_A : PORT_B);
+	     port <= (phy == BXT_PHY_A ? PORT_A : PORT_C); port++) {
+		int lane;
+
+		for (lane = 0; lane < 4; lane++) {
+			val = I915_READ(BXT_PORT_TX_DW14_LN(port, lane));
+			val &= ~LATENCY_OPTIM;
+			if (lane == 1)
+				val |= LATENCY_OPTIM;
+
+			I915_WRITE(BXT_PORT_TX_DW14_LN(port, lane), val);
+		}
+	}
+
+	/* Program PLL Rcomp code offset */
+	val = I915_READ(BXT_PORT_CL1CM_DW9(phy));
+	val &= ~IREF0RC_OFFSET_MASK;
+	val |= 0xE4 << IREF0RC_OFFSET_SHIFT;
+	I915_WRITE(BXT_PORT_CL1CM_DW9(phy), val);
+
+	val = I915_READ(BXT_PORT_CL1CM_DW10(phy));
+	val &= ~IREF1RC_OFFSET_MASK;
+	val |= 0xE4 << IREF1RC_OFFSET_SHIFT;
+	I915_WRITE(BXT_PORT_CL1CM_DW10(phy), val);
+
+	/* Program power gating */
+	val = I915_READ(BXT_PORT_CL1CM_DW28(phy));
+	val |= OCL1_POWER_DOWN_EN | DW28_OLDO_DYN_PWR_DOWN_EN |
+		SUS_CLK_CONFIG;
+	I915_WRITE(BXT_PORT_CL1CM_DW28(phy), val);
+
+	if (phy == BXT_PHY_BC) {
+		val = I915_READ(BXT_PORT_CL2CM_DW6_BC);
+		val |= DW6_OLDO_DYN_PWR_DOWN_EN;
+		I915_WRITE(BXT_PORT_CL2CM_DW6_BC, val);
+	}
+
+	val = I915_READ(BXT_PORT_CL1CM_DW30(phy));
+	val &= ~OCL2_LDOFUSE_PWR_DIS;
+	/*
+	 * On PHY_A disable power on the second channel, since no port is
+	 * connected there. On PHY_BC both channels have a port, so leave it
+	 * enabled.
+	 * Note that port C is only connected on BXT-P, so on BXT0/1 we should
+	 * power down the second channel on PHY_BC as well.
+	 */
+	if (phy == BXT_PHY_A)
+		val |= OCL2_LDOFUSE_PWR_DIS;
+	I915_WRITE(BXT_PORT_CL1CM_DW30(phy), val);
+
+	if (phy == BXT_PHY_BC) {
+		uint32_t grc_code;
+		/*
+		 * PHY_BC isn't connected to an RCOMP resistor so copy over
+		 * the corresponding calibrated value from PHY_A, and disable
+		 * the automatic calibration on PHY_BC.
+		 */
+		if (wait_for(I915_READ(BXT_PORT_REF_DW3(BXT_PHY_A)) & GRC_DONE,
+			     10))
+			DRM_ERROR("timeout waiting for PHY#0 GRC\n");
+
+		val = I915_READ(BXT_PORT_REF_DW6(BXT_PHY_A));
+		val = (val & GRC_CODE_MASK) >> GRC_CODE_SHIFT;
+		grc_code = val << GRC_CODE_FAST_SHIFT |
+			   val << GRC_CODE_SLOW_SHIFT |
+			   val;
+		I915_WRITE(BXT_PORT_REF_DW6(BXT_PHY_BC), grc_code);
+
+		val = I915_READ(BXT_PORT_REF_DW8(BXT_PHY_BC));
+		val |= GRC_DIS | GRC_RDY_OVRD;
+		I915_WRITE(BXT_PORT_REF_DW8(BXT_PHY_BC), val);
+	}
+
+	/* Release common_reset */
+	val = I915_READ(BXT_PHY_CTL_FAMILY(phy));
+	val |= COMMON_RESET_DIS;
+	I915_WRITE(BXT_PHY_CTL_FAMILY(phy), val);
+}
+
+void bxt_ddi_phy_init(struct drm_device *dev)
+{
+	/* Enable PHY_A first since it provides Rcomp for PHY_BC */
+	bxt_init_phy(dev->dev_private, BXT_PHY_A);
+	bxt_init_phy(dev->dev_private, BXT_PHY_BC);
+}
+
+static void bxt_ddi_phy_uninit(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	uint32_t temp;
+
+	temp = I915_READ(BXT_PHY_CTL_FAMILY(BXT_PHY_A));
+	I915_WRITE(BXT_PHY_CTL_FAMILY(BXT_PHY_A), temp & ~COMMON_RESET_DIS);
+
+	temp = I915_READ(BXT_PHY_CTL_FAMILY(BXT_PHY_BC));
+	I915_WRITE(BXT_PHY_CTL_FAMILY(BXT_PHY_BC), temp & ~COMMON_RESET_DIS);
+
+	I915_WRITE(BXT_P_CR_GT_DISP_PWRON_0_2_0_GTTMMADR, 0);
+}
+
+/*
+ * It is the responsibility of the caller to ensure that
+ * criteria for changing the CD clk frequency is met.
+ *
+ * This function only changes CD clock frequency.
+ * TODO:- 1. Add functions to change only the divider and
+ *	  2. call impacted functions like backlight, WiDi, watermark.
+*/
+void bxt_select_cdclk_freq(struct drm_device *dev, u32 frequency)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	uint32_t cdclk_ctl, decimal, ratio;
+	uint32_t divider, freq, current_freq;
+	int ret;
+
+	freq = (frequency / 1000 - 1) * 2;
+	decimal = DIV_ROUND_UP(frequency, 25000);
+
+	switch (frequency) {
+	case 144000:
+		divider = BXT_CDCLK_CD2X_DIV_SEL_4;
+		ratio = BXT_DE_PLL_RATIO_1152;
+		break;
+	case 288000:
+		divider = BXT_CDCLK_CD2X_DIV_SEL_2;
+		ratio = BXT_DE_PLL_RATIO_1152;
+		break;
+	case 384000:
+		divider = BXT_CDCLK_CD2X_DIV_SEL_1_5;
+		ratio = BXT_DE_PLL_RATIO_1152;
+		break;
+	case 576000:
+		divider = BXT_CDCLK_CD2X_DIV_SEL_1;
+		ratio = BXT_DE_PLL_RATIO_1152;
+		break;
+	case 624000:
+		divider = BXT_CDCLK_CD2X_DIV_SEL_1;
+		ratio = BXT_DE_PLL_RATIO_1248;
+		break;
+	case 0:
+		/* Incase incoming frequency is 0, only DE PLL has to be
+		 * disabled, divider/ratio need not be programmed.
+		 * Hence, initializing to 0.
+		 */
+		divider = ratio = 0;
+		break;
+	default:
+		DRM_ERROR("Unsupported cd frequency %d enable request",
+								frequency);
+		return;
+	}
+
+	current_freq = I915_READ(CDCLK_CTL) & CDCLK_FREQ_DECIMAL_MASK;
+	current_freq = ((current_freq / 2) + 1) * 1000;
+
+	mutex_lock(&dev_priv->rps.hw_lock);
+	/* Inform power controller of upcoming frequency change */
+	ret = sandybridge_pcode_write(dev_priv, DISPLAY_PCU_CONTROL,
+				      0x80000000);
+	mutex_unlock(&dev_priv->rps.hw_lock);
+
+	if (ret) {
+		DRM_DEBUG_KMS("pcode write failed, leaving CDCLK unchanged (%d)\n",
+			      ret);
+		return;
+	}
+
+	/* DE PLL has to be disabled when input frequency is 0 or
+	 * frequency is to be changed to 624MHz or changed from 624 MHz
+	 */
+	if (!frequency || current_freq == 624000 || frequency == 624000) {
+		I915_WRITE(BXT_DE_PLL_ENABLE, ~BXT_DE_PLL_PLL_ENABLE);
+		WARN(wait_for(
+			!(I915_READ(BXT_DE_PLL_ENABLE) & BXT_DE_PLL_LOCK),
+			1), "DE PLL locked\n");
+	}
+
+	if (frequency) {
+		I915_WRITE(BXT_DE_PLL_CTL, ratio);
+		I915_WRITE(BXT_DE_PLL_ENABLE, BXT_DE_PLL_PLL_ENABLE);
+		WARN(wait_for(
+			I915_READ(BXT_DE_PLL_ENABLE) & BXT_DE_PLL_LOCK, 1),
+			"DE PLL not locked\n");
+
+		cdclk_ctl = I915_READ(CDCLK_CTL);
+		cdclk_ctl &= ~BXT_CDCLK_CD2X_DIV_SEL_MASK;
+		cdclk_ctl |= divider;
+
+		/* Disable SSA Precharge when CD clock frequency < 500 MHz,
+		 * enable otherwise.
+		 */
+		cdclk_ctl &= ~BXT_CDCLK_SSA_PRECHARGE_ENABLE;
+		if (frequency >= 500000)
+			cdclk_ctl |= BXT_CDCLK_SSA_PRECHARGE_ENABLE;
+
+		cdclk_ctl &= ~CDCLK_FREQ_DECIMAL_MASK;
+		cdclk_ctl |= freq;
+		I915_WRITE(CDCLK_CTL, cdclk_ctl);
+
+		mutex_lock(&dev_priv->rps.hw_lock);
+		ret = sandybridge_pcode_write(dev_priv, DISPLAY_PCU_CONTROL,
+					      decimal);
+		mutex_unlock(&dev_priv->rps.hw_lock);
+
+		if (ret) {
+			DRM_DEBUG_KMS("pcode write failed. err = %d decimal = %d\n",
+				      ret, decimal);
+			return;
+		}
+
+		dev_priv->cdclk_freq = frequency;
+	} else {
+		mutex_lock(&dev_priv->rps.hw_lock);
+		ret = sandybridge_pcode_write(dev_priv, DISPLAY_PCU_CONTROL, 1);
+		mutex_unlock(&dev_priv->rps.hw_lock);
+
+		if (ret)
+			DRM_DEBUG_KMS("pcode write failed. err = %d decimal = 1\n",
+				      ret);
+	}
+}
+
+void bxt_init_cdclk(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	/* NDE_RSTWRN_OPT RST PCH Handshake En must always be 0b on BXT
+	 * or else the reset will hang because there is no PCH to respond.
+	 * Move the handshake programming to initialization sequence.
+	 * Previously was left up to BIOS.
+	 */
+	u32 temp = I915_READ(HSW_NDE_RSTWRN_OPT);
+
+	temp &= ~RESET_PCH_HANDSHAKE_ENABLE;
+	I915_WRITE(HSW_NDE_RSTWRN_OPT, temp);
+
+	/* Enable PG1 for cdclk */
+	intel_display_power_get(dev_priv, POWER_DOMAIN_PLLS);
+
+	/* check if cd clock is enabled */
+	if (I915_READ(BXT_DE_PLL_ENABLE) & BXT_DE_PLL_PLL_ENABLE) {
+		DRM_DEBUG_KMS("Display already initialized\n");
+		return;
+	}
+
+	/* FIXME:- The initial CDCLK needs to be read from VBT.
+	 * Need to make this change after VBT has changes for BXT.
+	 */
+	bxt_select_cdclk_freq(dev, 624000);
+
+	I915_WRITE(DBUF_CTL, I915_READ(DBUF_CTL) | DBUF_POWER_REQUEST);
+	udelay(10);
+
+	if (!(I915_READ(DBUF_CTL) & DBUF_POWER_STATE))
+		DRM_ERROR("DBuf power enable timeout!\n");
+}
+
+void bxt_uninit_cdclk(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	bxt_ddi_phy_uninit(dev);
+
+	I915_WRITE(DBUF_CTL, I915_READ(DBUF_CTL) & ~DBUF_POWER_REQUEST);
+	udelay(10);
+
+	if (I915_READ(DBUF_CTL) & DBUF_POWER_STATE)
+		DRM_ERROR("DBuf power disable timeout!\n");
+
+	bxt_select_cdclk_freq(dev, 0);
+
+	intel_display_power_put(dev_priv, POWER_DOMAIN_PLLS);
+}
+
 void intel_ddi_pll_init(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1973,6 +2261,9 @@ void intel_ddi_pll_init(struct drm_device *dev)
 	if (IS_SKYLAKE(dev)) {
 		if (!(I915_READ(LCPLL1_CTL) & LCPLL_PLL_ENABLE))
 			DRM_ERROR("LCPLL1 is disabled\n");
+	} else if (IS_BROXTON(dev)) {
+		bxt_init_cdclk(dev);
+		bxt_ddi_phy_init(dev);
 	} else {
 		/*
 		 * The LCPLL register should be turned on by the BIOS. For now
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index b91862e..ba2d1ae 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8284,6 +8284,75 @@ void hsw_disable_pc8(struct drm_i915_private *dev_priv)
 	intel_prepare_ddi(dev);
 }
 
+static int broxton_calc_cdclk(struct drm_i915_private *dev_priv,
+				int max_pixclk)
+{
+	/*
+	 * CDclks are supported:
+	 *   144MHz
+	 *   288MHz
+	 *   384MHz
+	 *   576MHz
+	 *   624MHz
+	 * Check to see whether we're above 90% of the lower bin and
+	 * adjust if needed.
+	 */
+
+	/* If max_pixclk is greater than the max allowed clock, return 0.
+	 * FIXME:- The max clock allowed needs to be provided by GOP/VBIOS
+	 * via a scratch pad register. Till that is enabled, use 624MHz as max.
+	 */
+	if (max_pixclk > 624000)
+		return 0;
+	else if (max_pixclk > 576000*9/10)
+		return 624000;
+	else if (max_pixclk > 384000*9/10)
+		return 576000;
+	else if (max_pixclk > 288000*9/10)
+		return 384000;
+	else if (max_pixclk > 144000*9/10)
+		return 288000;
+	else
+		return 144000;
+}
+
+static void broxton_modeset_global_pipes(struct drm_device *dev,
+					    unsigned *prepare_pipes)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_crtc *intel_crtc;
+	int max_pixclk = intel_mode_max_pixclk(dev_priv);
+	int req_cdclk = broxton_calc_cdclk(dev_priv, max_pixclk);
+
+	if (!req_cdclk) {
+		DRM_ERROR("CDCLK exceeds maximum allowable value\n");
+		return;
+	}
+
+	if (req_cdclk == dev_priv->cdclk_freq)
+		return;
+
+	/* disable/enable all currently active pipes while we change cdclk */
+	for_each_intel_crtc(dev, intel_crtc)
+		if (intel_crtc->base.enabled)
+			*prepare_pipes |= (1 << intel_crtc->pipe);
+}
+
+static void broxton_modeset_global_resources(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	int max_pixclk = intel_mode_max_pixclk(dev_priv);
+	int req_cdclk = broxton_calc_cdclk(dev_priv, max_pixclk);
+
+	if (!req_cdclk) {
+		DRM_ERROR("CDCLK exceeds maximum allowable value\n");
+		return;
+	}
+
+	if (req_cdclk != dev_priv->cdclk_freq)
+		bxt_select_cdclk_freq(dev, req_cdclk);
+}
+
 static int haswell_crtc_compute_clock(struct intel_crtc *crtc,
 				      struct intel_crtc_state *crtc_state)
 {
@@ -11239,6 +11308,9 @@ static int __intel_set_mode(struct drm_crtc *crtc,
 
 		/* may have added more to prepare_pipes than we should */
 		prepare_pipes &= ~disable_pipes;
+	} else if (IS_BROXTON(dev)) {
+		broxton_modeset_global_pipes(dev, &prepare_pipes);
+		prepare_pipes &= ~disable_pipes;
 	}
 
 	ret = __intel_set_mode_setup_plls(dev, modeset_pipes, disable_pipes);
@@ -13133,6 +13205,9 @@ static void intel_init_display(struct drm_device *dev)
 	} else if (IS_VALLEYVIEW(dev)) {
 		dev_priv->display.modeset_global_resources =
 			valleyview_modeset_global_resources;
+	} else if (IS_BROXTON(dev)) {
+		dev_priv->display.modeset_global_resources =
+			broxton_modeset_global_resources;
 	}
 
 	switch (INTEL_INFO(dev)->gen) {
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index c77128c..4bc2041 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -873,6 +873,7 @@ void intel_ddi_init_dp_buf_reg(struct intel_encoder *encoder);
 void intel_ddi_clock_get(struct intel_encoder *encoder,
 			 struct intel_crtc_state *pipe_config);
 void intel_ddi_set_vc_payload_alloc(struct drm_crtc *crtc, bool state);
+void bxt_select_cdclk_freq(struct drm_device *dev, u32 frequency);
 
 /* intel_frontbuffer.c */
 void intel_fb_obj_invalidate(struct drm_i915_gem_object *obj,
@@ -1020,6 +1021,9 @@ void intel_prepare_reset(struct drm_device *dev);
 void intel_finish_reset(struct drm_device *dev);
 void hsw_enable_pc8(struct drm_i915_private *dev_priv);
 void hsw_disable_pc8(struct drm_i915_private *dev_priv);
+void bxt_init_cdclk(struct drm_device *dev);
+void bxt_uninit_cdclk(struct drm_device *dev);
+void bxt_ddi_phy_init(struct drm_device *dev);
 void intel_dp_get_m_n(struct intel_crtc *crtc,
 		      struct intel_crtc_state *pipe_config);
 void intel_dp_set_m_n(struct intel_crtc *crtc, enum link_m_n_set m_n);
-- 
2.1.0



More information about the Intel-gfx mailing list