diff mbox

[48/49] drm/i915/bxt: VSwing programming sequence

Message ID 1426585215-8788-49-git-send-email-imre.deak@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Imre Deak March 17, 2015, 9:40 a.m. UTC
From: Vandana Kannan <vandana.kannan@intel.com>

VSwing programming sequence as specified in the updated BXT BSpec

v2: Satheesh's review comments addressed.
- clear value before setting into registers
- move print statement to bxt function
Other changes
- since signal level will not be set into DDI_BUF_CTL, the value need
  not be returned to intel_dp_set_signal_levels(). Making the bxt
  specific function to return void and setting signal_levels = 0 for
  bxt inside intel_dp_set_signal_levels()
- instead of signal levels, printing vswing level and pre-emphasis
  level
- in case none of the pre-emphasis levels or vswing levels are set,
  setting default of 400mV + 0dB

v3: Satheesh's review comments
- Check for mask before printing signal_levels.
- Removing redundant register writes
- Call intel_prepare_ddi_buffers only for HAS_PCH_SPLIT
- Making register write part generic as it will be required for HDMI as
  well.

Re-structure the code to include an array for vswing related values, set
signal levels

v4: Satheesh's review comments
- Rebase over latest renaming patches
- use hsw_signal_levels for HAS_DDI
Other changes
- Modified vswing_sequence() func definition
- Rebased on top of register macro definitions

v5: Satheesh's review comments
- Check ddi translation table size

v6: Imre's review comments
- removed comments in vswing sequence
- added vswing, pre-emphasis prints in intel_dp_set_signal_levels
- added comment explaining use of DP vswing values for eDP
- initialize n_entries and ddi_transaltion table based on encoder type
- create bxt_ddi_buf_trans structure and use decimal values
- adding a flag in bxt buffer translation table to indicate def entry

v7: (imre)
- squash in Vandana's "VSwing register definition",
  "HDMI VSwing programming", "Re-enable vswing programming",
  "Fix vswing sequence" patches
- use BXT_PORT_* regs directly instead of via a temp var
- simplify BXT_PORT_* macro definitions
- add code comment why we read lane while write group registers
- fix readout of DP_TRAIN_PRE_EMPHASIS in debug message

Signed-off-by: Vandana Kannan <vandana.kannan@intel.com> (v6)
Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h  |  61 ++++++++++++++++++++
 drivers/gpu/drm/i915/intel_ddi.c | 120 ++++++++++++++++++++++++++++++++++++++-
 drivers/gpu/drm/i915/intel_dp.c  |  64 ++++++++++++++++++++-
 drivers/gpu/drm/i915/intel_drv.h |   2 +
 4 files changed, 244 insertions(+), 3 deletions(-)

Comments

Sivakumar Thulasimani March 24, 2015, 9:19 a.m. UTC | #1
On 3/17/2015 3:10 PM, Imre Deak wrote:
> From: Vandana Kannan <vandana.kannan@intel.com>
>
> VSwing programming sequence as specified in the updated BXT BSpec
> ...
> ...
>   
> +void bxt_ddi_vswing_sequence(struct drm_device *dev, u32 level,
> +			     enum port port, int type)
> +{
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	const struct bxt_ddi_buf_trans *ddi_translations;
> +	u32 n_entries, i;
> +	uint32_t val;
> +
> +	if (type == INTEL_OUTPUT_DISPLAYPORT || type == INTEL_OUTPUT_EDP) {
INTEL_OUPPUT_DP_MST might be needed here, please check once. otherwise 
fine with the changes.
Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Imre Deak April 9, 2015, 5:14 p.m. UTC | #2
Hi Sivakumar,

On Tue, 2015-03-24 at 14:49 +0530, Sivakumar Thulasimani wrote:

> On 3/17/2015 3:10 PM, Imre Deak wrote:
> 
> > From: Vandana Kannan <vandana.kannan@intel.com>
> > 
> > VSwing programming sequence as specified in the updated BXT BSpec
> > ...
> > ...
> >  
> > +void bxt_ddi_vswing_sequence(struct drm_device *dev, u32 level,
> > +			     enum port port, int type)
> > +{
> > +	struct drm_i915_private *dev_priv = dev->dev_private;
> > +	const struct bxt_ddi_buf_trans *ddi_translations;
> > +	u32 n_entries, i;
> > +	uint32_t val;
> > +
> > +	if (type == INTEL_OUTPUT_DISPLAYPORT || type == INTEL_OUTPUT_EDP) {
> INTEL_OUPPUT_DP_MST might be needed here, please check once. otherwise
> fine with the changes.

Tbh, I had to check this after you brought this up: we can't get here
with INTEL_OUTPUT_DP_MST. That type is only assigned to "fake" encoders,
which only handle the MST aspects of the modeset. An MST encoder like
this will have an associated "primary" encoder (available via its
"primary" digital port field) which will handle the ordinary DP aspects
of the modeset. So link training as such is handled by the primary
encoder which for DP will be always either INTEL_OUTPUT_DISPLAYPORT or
INTEL_OUTPUT_EDP.

Thanks for pointing this out,
Imre

> Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 2e72283c..545b7cf 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1269,6 +1269,21 @@  enum bxt_phy {
 						     _PORT_REF_DW8_BC)
 
 /* BXT PHY PCS registers */
+#define _PORT_PCS_DW10_LN01_A		0x162428
+#define _PORT_PCS_DW10_LN01_B		0x6C428
+#define _PORT_PCS_DW10_LN01_C		0x6C828
+#define _PORT_PCS_DW10_GRP_A		0x162C28
+#define _PORT_PCS_DW10_GRP_B		0x6CC28
+#define _PORT_PCS_DW10_GRP_C		0x6CE28
+#define BXT_PORT_PCS_DW10_LN01(port)	_PORT3(port, _PORT_PCS_DW10_LN01_A, \
+						     _PORT_PCS_DW10_LN01_B, \
+						     _PORT_PCS_DW10_LN01_C)
+#define BXT_PORT_PCS_DW10_GRP(port)	_PORT3(port, _PORT_PCS_DW10_GRP_A,  \
+						     _PORT_PCS_DW10_GRP_B,  \
+						     _PORT_PCS_DW10_GRP_C)
+#define   TX2_SWING_CALC_INIT		(1 << 31)
+#define   TX1_SWING_CALC_INIT		(1 << 30)
+
 #define _PORT_PCS_DW12_LN01_A		0x162430
 #define _PORT_PCS_DW12_LN01_B		0x6C430
 #define _PORT_PCS_DW12_LN01_C		0x6C830
@@ -1294,6 +1309,52 @@  enum bxt_phy {
 #define BXT_LANE_OFFSET(lane)           (((lane) >> 1) * 0x200 +	\
 					 ((lane) & 1) * 0x80)
 
+#define _PORT_TX_DW2_LN0_A		0x162508
+#define _PORT_TX_DW2_LN0_B		0x6C508
+#define _PORT_TX_DW2_LN0_C		0x6C908
+#define _PORT_TX_DW2_GRP_A		0x162D08
+#define _PORT_TX_DW2_GRP_B		0x6CD08
+#define _PORT_TX_DW2_GRP_C		0x6CF08
+#define BXT_PORT_TX_DW2_GRP(port)	_PORT3(port, _PORT_TX_DW2_GRP_A,  \
+						     _PORT_TX_DW2_GRP_B,  \
+						     _PORT_TX_DW2_GRP_C)
+#define BXT_PORT_TX_DW2_LN0(port)	_PORT3(port, _PORT_TX_DW2_LN0_A,  \
+						     _PORT_TX_DW2_LN0_B,  \
+						     _PORT_TX_DW2_LN0_C)
+#define   MARGIN_000_SHIFT		16
+#define   MARGIN_000			(0xFF << MARGIN_000_SHIFT)
+#define   UNIQ_TRANS_SCALE_SHIFT	8
+#define   UNIQ_TRANS_SCALE		(0xFF << UNIQ_TRANS_SCALE_SHIFT)
+
+#define _PORT_TX_DW3_LN0_A		0x16250C
+#define _PORT_TX_DW3_LN0_B		0x6C50C
+#define _PORT_TX_DW3_LN0_C		0x6C90C
+#define _PORT_TX_DW3_GRP_A		0x162D0C
+#define _PORT_TX_DW3_GRP_B		0x6CD0C
+#define _PORT_TX_DW3_GRP_C		0x6CF0C
+#define BXT_PORT_TX_DW3_GRP(port)	_PORT3(port, _PORT_TX_DW3_GRP_A,  \
+						     _PORT_TX_DW3_GRP_B,  \
+						     _PORT_TX_DW3_GRP_C)
+#define BXT_PORT_TX_DW3_LN0(port)	_PORT3(port, _PORT_TX_DW3_LN0_A,  \
+						     _PORT_TX_DW3_LN0_B,  \
+						     _PORT_TX_DW3_LN0_C)
+#define   UNIQE_TRANGE_EN_METHOD	(1 << 27)
+
+#define _PORT_TX_DW4_LN0_A		0x162510
+#define _PORT_TX_DW4_LN0_B		0x6C510
+#define _PORT_TX_DW4_LN0_C		0x6C910
+#define _PORT_TX_DW4_GRP_A		0x162D10
+#define _PORT_TX_DW4_GRP_B		0x6CD10
+#define _PORT_TX_DW4_GRP_C		0x6CF10
+#define BXT_PORT_TX_DW4_LN0(port)	_PORT3(port, _PORT_TX_DW4_LN0_A,  \
+						     _PORT_TX_DW4_LN0_B,  \
+						     _PORT_TX_DW4_LN0_C)
+#define BXT_PORT_TX_DW4_GRP(port)	_PORT3(port, _PORT_TX_DW4_GRP_A,  \
+						     _PORT_TX_DW4_GRP_B,  \
+						     _PORT_TX_DW4_GRP_C)
+#define   DEEMPH_SHIFT			24
+#define   DE_EMPHASIS			(0xFF << DEEMPH_SHIFT)
+
 #define _PORT_TX_DW14_LN0_A		0x162538
 #define _PORT_TX_DW14_LN0_B		0x6C538
 #define _PORT_TX_DW14_LN0_C		0x6C938
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index 5aa4dab..799f9fc 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -159,6 +159,48 @@  static const struct ddi_buf_trans skl_ddi_translations_hdmi[] = {
 	{ 0x00004014, 0x00000087 },	/* 0:	800	1000	2   */
 };
 
+struct bxt_ddi_buf_trans {
+	u32 margin;	/* swing value */
+	u32 scale;	/* scale value */
+	u32 enable;	/* scale enable */
+	u32 deemphasis;
+	bool default_index; /* true if the entry represents default value */
+};
+
+/* BSpec does not define separate vswing/pre-emphasis values for eDP.
+ * Using DP values for eDP as well.
+ */
+static const struct bxt_ddi_buf_trans bxt_ddi_translations_dp[] = {
+					/* Idx	NT mV diff	db  */
+	{ 52,  0,    0, 128, true  },	/* 0:	400		0   */
+	{ 78,  0,    0, 85,  false },	/* 1:	400		3.5 */
+	{ 104, 0,    0, 64,  false },	/* 2:	400		6   */
+	{ 154, 0,    0, 43,  false },	/* 3:	400		9.5 */
+	{ 77,  0,    0, 128, false },	/* 4:	600		0   */
+	{ 116, 0,    0, 85,  false },	/* 5:	600		3.5 */
+	{ 154, 0,    0, 64,  false },	/* 6:	600		6   */
+	{ 102, 0,    0, 128, false },	/* 7:	800		0   */
+	{ 154, 0,    0, 85,  false },	/* 8:	800		3.5 */
+	{ 154, 0x9A, 1, 128, false },  /* 9:	1200		0   */
+};
+
+/* BSpec has 2 recommended values - entries 0 and 8.
+ * Using the entry with higher vswing.
+ */
+static const struct bxt_ddi_buf_trans bxt_ddi_translations_hdmi[] = {
+					/* Idx	NT mV diff	db  */
+	{ 52,  0,    0, 128, false },	/* 0:	400		0   */
+	{ 52,  0,    0, 85,  false },	/* 1:	400		3.5 */
+	{ 52,  0,    0, 64,  false },	/* 2:	400		6   */
+	{ 42,  0,    0, 43,  false },	/* 3:	400		9.5 */
+	{ 77,  0,    0, 128, false },	/* 4:	600		0   */
+	{ 77,  0,    0, 85,  false },	/* 5:	600		3.5 */
+	{ 77,  0,    0, 64,  false },	/* 6:	600		6   */
+	{ 102, 0,    0, 128, false },	/* 7:	800		0   */
+	{ 102, 0,    0, 85,  false },	/* 8:	800		3.5 */
+	{ 154, 0x9A, 1, 128, true },	/* 9:	1200		0   */
+};
+
 enum port intel_ddi_get_encoder_port(struct intel_encoder *intel_encoder)
 {
 	struct drm_encoder *encoder = &intel_encoder->base;
@@ -210,7 +252,15 @@  static void intel_prepare_ddi_buffers(struct drm_device *dev,
 	const struct ddi_buf_trans *ddi_translations_hdmi;
 	const struct ddi_buf_trans *ddi_translations;
 
-	if (IS_SKYLAKE(dev)) {
+	if (IS_BROXTON(dev)) {
+		if (!intel_dig_port_supports_hdmi(intel_dig_port))
+			return;
+
+		/* Vswing programming for HDMI */
+		bxt_ddi_vswing_sequence(dev, hdmi_level, port,
+					INTEL_OUTPUT_HDMI);
+		return;
+	} else if (IS_SKYLAKE(dev)) {
 		ddi_translations_fdi = NULL;
 		ddi_translations_dp = skl_ddi_translations_dp;
 		n_dp_entries = ARRAY_SIZE(skl_ddi_translations_dp);
@@ -1666,6 +1716,67 @@  void intel_ddi_disable_pipe_clock(struct intel_crtc *intel_crtc)
 			   TRANS_CLK_SEL_DISABLED);
 }
 
+void bxt_ddi_vswing_sequence(struct drm_device *dev, u32 level,
+			     enum port port, int type)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	const struct bxt_ddi_buf_trans *ddi_translations;
+	u32 n_entries, i;
+	uint32_t val;
+
+	if (type == INTEL_OUTPUT_DISPLAYPORT || type == INTEL_OUTPUT_EDP) {
+		n_entries = ARRAY_SIZE(bxt_ddi_translations_dp);
+		ddi_translations = bxt_ddi_translations_dp;
+	} else if (type == INTEL_OUTPUT_HDMI) {
+		n_entries = ARRAY_SIZE(bxt_ddi_translations_hdmi);
+		ddi_translations = bxt_ddi_translations_hdmi;
+	} else {
+		DRM_DEBUG_KMS("Vswing programming not done for encoder %d\n",
+				type);
+		return;
+	}
+
+	/* Check if default value has to be used */
+	if (level >= n_entries ||
+	    (type == INTEL_OUTPUT_HDMI && level == HDMI_LEVEL_SHIFT_UNKNOWN)) {
+		for (i = 0; i < n_entries; i++) {
+			if (ddi_translations[i].default_index) {
+				level = i;
+				break;
+			}
+		}
+	}
+
+	/*
+	 * While we write to the group register to program all lanes at once we
+	 * can read only lane registers and we pick lanes 0/1 for that.
+	 */
+	val = I915_READ(BXT_PORT_PCS_DW10_LN01(port));
+	val &= ~(TX2_SWING_CALC_INIT | TX1_SWING_CALC_INIT);
+	I915_WRITE(BXT_PORT_PCS_DW10_GRP(port), val);
+
+	val = I915_READ(BXT_PORT_TX_DW2_LN0(port));
+	val &= ~(MARGIN_000 | UNIQ_TRANS_SCALE);
+	val |= ddi_translations[level].margin << MARGIN_000_SHIFT |
+	       ddi_translations[level].scale << UNIQ_TRANS_SCALE_SHIFT;
+	I915_WRITE(BXT_PORT_TX_DW2_GRP(port), val);
+
+	val = I915_READ(BXT_PORT_TX_DW3_LN0(port));
+	val &= ~UNIQE_TRANGE_EN_METHOD;
+	if (ddi_translations[level].enable)
+		val |= UNIQE_TRANGE_EN_METHOD;
+	I915_WRITE(BXT_PORT_TX_DW3_GRP(port), val);
+
+	val = I915_READ(BXT_PORT_TX_DW4_LN0(port));
+	val &= ~DE_EMPHASIS;
+	val |= ddi_translations[level].deemphasis << DEEMPH_SHIFT;
+	I915_WRITE(BXT_PORT_TX_DW4_GRP(port), val);
+
+	val = I915_READ(BXT_PORT_PCS_DW10_LN01(port));
+	val |= TX2_SWING_CALC_INIT | TX1_SWING_CALC_INIT;
+	I915_WRITE(BXT_PORT_PCS_DW10_GRP(port), val);
+}
+
 static void intel_ddi_pre_enable(struct intel_encoder *intel_encoder)
 {
 	struct drm_encoder *encoder = &intel_encoder->base;
@@ -1674,6 +1785,7 @@  static void intel_ddi_pre_enable(struct intel_encoder *intel_encoder)
 	struct intel_crtc *crtc = to_intel_crtc(encoder->crtc);
 	enum port port = intel_ddi_get_encoder_port(intel_encoder);
 	int type = intel_encoder->type;
+	int hdmi_level;
 
 	if (type == INTEL_OUTPUT_EDP) {
 		struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
@@ -1730,6 +1842,12 @@  static void intel_ddi_pre_enable(struct intel_encoder *intel_encoder)
 	} else if (type == INTEL_OUTPUT_HDMI) {
 		struct intel_hdmi *intel_hdmi = enc_to_intel_hdmi(encoder);
 
+		if (IS_BROXTON(dev)) {
+			hdmi_level = dev_priv->vbt.
+				ddi_port_info[port].hdmi_level_shift;
+			bxt_ddi_vswing_sequence(dev, hdmi_level, port,
+					INTEL_OUTPUT_HDMI);
+		}
 		intel_hdmi->set_infoframes(encoder,
 					   crtc->config->has_hdmi_sink,
 					   &crtc->config->base.adjusted_mode);
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 4bfbeed..1cb6eb0 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -3354,6 +3354,55 @@  intel_hsw_signal_levels(uint8_t train_set)
 	}
 }
 
+static void intel_bxt_signal_levels(struct intel_dp *intel_dp)
+{
+	struct intel_digital_port *dport = dp_to_dig_port(intel_dp);
+	enum port port = dport->port;
+	struct drm_device *dev = dport->base.base.dev;
+	struct intel_encoder *encoder = &dport->base;
+	uint8_t train_set = intel_dp->train_set[0];
+	uint32_t level = 0;
+
+	int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
+					 DP_TRAIN_PRE_EMPHASIS_MASK);
+	switch (signal_levels) {
+	default:
+		DRM_DEBUG_KMS("Unsupported voltage swing/pre-emph level\n");
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+		level = 0;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_1:
+		level = 1;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_2:
+		level = 2;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_3:
+		level = 3;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+		level = 4;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_1:
+		level = 5;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_2:
+		level = 6;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+		level = 7;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_1:
+		level = 8;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_3 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+		level = 9;
+		break;
+	}
+
+	bxt_ddi_vswing_sequence(dev, level, port, encoder->type);
+}
+
 /* Properly updates "DP" with the correct signal levels. */
 static void
 intel_dp_set_signal_levels(struct intel_dp *intel_dp, uint32_t *DP)
@@ -3364,7 +3413,11 @@  intel_dp_set_signal_levels(struct intel_dp *intel_dp, uint32_t *DP)
 	uint32_t signal_levels, mask;
 	uint8_t train_set = intel_dp->train_set[0];
 
-	if (IS_HASWELL(dev) || IS_BROADWELL(dev) || INTEL_INFO(dev)->gen >= 9) {
+	if (IS_BROXTON(dev)) {
+		signal_levels = 0;
+		intel_bxt_signal_levels(intel_dp);
+		mask = 0;
+	} else if (HAS_DDI(dev)) {
 		signal_levels = intel_hsw_signal_levels(train_set);
 		mask = DDI_BUF_EMP_MASK;
 	} else if (IS_CHERRYVIEW(dev)) {
@@ -3384,7 +3437,14 @@  intel_dp_set_signal_levels(struct intel_dp *intel_dp, uint32_t *DP)
 		mask = DP_VOLTAGE_MASK | DP_PRE_EMPHASIS_MASK;
 	}
 
-	DRM_DEBUG_KMS("Using signal levels %08x\n", signal_levels);
+	if (mask)
+		DRM_DEBUG_KMS("Using signal levels %08x\n", signal_levels);
+
+	DRM_DEBUG_KMS("Using vswing level %d\n",
+		train_set & DP_TRAIN_VOLTAGE_SWING_MASK);
+	DRM_DEBUG_KMS("Using pre-emphasis level %d\n",
+		(train_set & DP_TRAIN_PRE_EMPHASIS_MASK) >>
+			DP_TRAIN_PRE_EMPHASIS_SHIFT);
 
 	*DP = (*DP & ~mask) | signal_levels;
 }
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 097fb85..f07a14a 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -874,6 +874,8 @@  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);
+void bxt_ddi_vswing_sequence(struct drm_device *dev, u32 level,
+				enum port port, int type);
 
 /* intel_frontbuffer.c */
 void intel_fb_obj_invalidate(struct drm_i915_gem_object *obj,