regulator: cpr3: Add voltage boost support for CPR4 controllers

Voltage boost is a CPR4 hardware feature which raises the VDD supply
voltage when the number of active cores reaches a certain threshold.
It then reduces the voltage back down when the active core count
condition is no longer met. Add support to enable and configure this
feature.

Change-Id: Iccfc2ddddb6621a150235cb2c46adfd1b884dbc2
Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>

4 files changed, 449 insertions, 34 deletions

diff --git a/Documentation/devicetree/bindings/regulator/cpr4-apss-regulator.txt b/Documentation/devicetree/bindings/regulator/cpr4-apss-regulator.txt
index 5b081119a944..61382b562676 100644
--- a/Documentation/devicetree/bindings/regulator/cpr4-apss-regulator.txt
+++ b/Documentation/devicetree/bindings/regulator/cpr4-apss-regulator.txt
@@ -291,6 +291,63 @@ APSS specific properties:
 		    speed bins 1-to-1 or exactly 1 list which is used regardless
 		    of the fuse combination and speed bin found on a given chip.
 
+- qcom,cpr-num-boost-cores
+	Usage:      required if qcom,allow-boost specified for this CPR3
+		    regulator.
+	Value type: <u32>
+	Definition: Integer value indicates that voltage boost will be applied
+		    when the number of online cores become this value.
+
+- qcom,cpr-boost-temp-adjustment
+	Usage:      optional
+	Value type: <prop-encoded-array>
+	Definition: A list of integer tuples which each define the temperature
+		    based voltage adjustment to boost voltage in microvolts
+		    for each temperature band in order from lowest to highest.
+
+		    The number of elements in each tuple should be equal to either
+		    (the number of elements in qcom,cpr-ctrl-temp-point-map
+		    + 1), if qcom,cpr-ctrl-temp-point-map is specified, or 1.
+
+		    The list must contain qcom,cpr-fuse-combos number of tuples
+		    in which case the tuples are matched to fuse combinations
+		    1-to-1 or qcom,cpr-speed-bins number of tuples in which case
+		    the tuples are matched to speed bins 1-to-1 or exactly 1
+		    tuple which is used regardless of the fuse combination and
+		    speed bin found on a given chip.
+
+- qcom,allow-boost
+	Usage:      optional
+	Value type: <prop-encoded-array>
+	Definition: A list of integers which specifies if the voltage boost
+		    feature should be enabled for each fuse combination.
+		    Supported per-combo element values:
+			0 - voltage boost feature disabled
+			1 - voltage boost feature enabled
+
+		    The list must contain qcom,cpr-fuse-combos number of
+		    elements in which case the elements are matched to fuse
+		    combinations 1-to-1 or qcom,cpr-speed-bins number of
+		    elements in which case the elements are matched to
+		    speed bins 1-to-1 or exactly 1 element which is used
+		    regardless of the fuse combination and speed bin found
+		    on a given chip.
+
+- qcom,cpr-boost-voltage-fuse-adjustment
+	Usage:      optional
+	Value type: <u32>
+	Definition: A list of integers which defines the voltage adjustment
+		    in microvolts for the fused boost voltage. This adjustment
+		    is applied to the values read from boost fuses.
+
+		    The list must contain qcom,cpr-fuse-combos number of
+		    elements in which case the elements are matched to fuse
+		    combinations 1-to-1 or qcom,cpr-speed-bins number of
+		    elements in which case the elements are matched to
+		    speed bins 1-to-1 or exactly 1 element which is used
+		    regardless of the fuse combination and speed bin found
+		    on a given chip.
+
 =======
 Example
 =======
@@ -420,6 +477,13 @@ apc_cpr: cpr4-ctrl@b018000 {
 				<(-30000) (-20000) (-10000)  (-5000)>,
 				<(-20000) (-10000)  (-5000)       0 >,
 				<(-20000) (-10000)  (-5000)       0 >;
+
+			qcom,cpr-num-boost-cores = <4>;
+			qcom,cpr-boost-voltage-fuse-adjustment = <(-10000)>;
+			qcom,cpr-boost-temp-adjustment =
+				<(-20000) (-15000) (-10000) 0>;
+			qcom,allow-boost =
+				<1>;
 		};
 	};
 };
diff --git a/drivers/regulator/cpr3-regulator.c b/drivers/regulator/cpr3-regulator.c
index b4d79772ad89..ca09c8d78c28 100644
--- a/drivers/regulator/cpr3-regulator.c
+++ b/drivers/regulator/cpr3-regulator.c
@@ -205,6 +205,7 @@
 #define CPR4_MARGIN_TEMP_POINT2_SHIFT		0
 
 #define CPR4_REG_MARGIN_ADJ_CTL					0x7F8
+#define CPR4_MARGIN_ADJ_CTL_BOOST_EN				BIT(0)
 #define CPR4_MARGIN_ADJ_CTL_CORE_ADJ_EN				BIT(1)
 #define CPR4_MARGIN_ADJ_CTL_TEMP_ADJ_EN				BIT(2)
 #define CPR4_MARGIN_ADJ_CTL_TIMER_SETTLE_VOLTAGE_EN		BIT(3)
@@ -335,7 +336,8 @@ static inline void cpr3_masked_write(struct cpr3_controller *ctrl, u32 offset,
  */
 static inline void cpr3_ctrl_loop_enable(struct cpr3_controller *ctrl)
 {
-	if (ctrl->cpr_enabled)
+	if (ctrl->cpr_enabled && !(ctrl->aggr_corner.sdelta
+		&& ctrl->aggr_corner.sdelta->allow_boost))
 		cpr3_masked_write(ctrl, CPR3_REG_CPR_CTL,
 			CPR3_CPR_CTL_LOOP_EN_MASK, CPR3_CPR_CTL_LOOP_ENABLE);
 }
@@ -417,7 +419,7 @@ static inline int cpr3_ctrl_clear_cpr4_config(struct cpr3_controller *ctrl)
 	int i, rc = 0;
 
 	if (!aggr_sdelta || !(aggr_sdelta->allow_core_count_adj
-		|| aggr_sdelta->allow_temp_adj))
+		|| aggr_sdelta->allow_temp_adj || aggr_sdelta->allow_boost))
 		/* cpr4 features are not enabled */
 		return 0;
 
@@ -439,13 +441,15 @@ static inline int cpr3_ctrl_clear_cpr4_config(struct cpr3_controller *ctrl)
 		CPR4_MARGIN_ADJ_CTL_MAX_NUM_CORES_MASK
 		| CPR4_MARGIN_ADJ_CTL_CORE_ADJ_EN
 		| CPR4_MARGIN_ADJ_CTL_TEMP_ADJ_EN
-		| CPR4_MARGIN_ADJ_CTL_KV_MARGIN_ADJ_EN, 0);
+		| CPR4_MARGIN_ADJ_CTL_KV_MARGIN_ADJ_EN
+		| CPR4_MARGIN_ADJ_CTL_BOOST_EN
+		| CPR4_MARGIN_ADJ_CTL_HW_CLOSED_LOOP_EN_MASK, 0);
 
 	cpr3_masked_write(ctrl, CPR4_REG_MISC,
 			CPR4_MISC_MARGIN_TABLE_ROW_SELECT_MASK,
 			0 << CPR4_MISC_MARGIN_TABLE_ROW_SELECT_SHIFT);
 
-	for (i = 0; i < aggr_sdelta->max_core_count; i++) {
+	for (i = 0; i <= aggr_sdelta->max_core_count; i++) {
 		/* Clear voltage margin adjustments programmed in TEMP_COREi */
 		cpr3_write(ctrl, CPR4_REG_MARGIN_TEMP_CORE(i), 0);
 	}
@@ -689,7 +693,8 @@ static int cpr3_regulator_init_cpr4(struct cpr3_controller *ctrl)
 		break;
 	}
 
-	if (!ctrl->allow_core_count_adj && !ctrl->allow_temp_adj) {
+	if (!ctrl->allow_core_count_adj && !ctrl->allow_temp_adj
+		&& !ctrl->allow_boost) {
 		/*
 		 * Skip below configuration as none of the features
 		 * are enabled.
@@ -758,7 +763,8 @@ static int cpr3_regulator_init_cpr4(struct cpr3_controller *ctrl)
 			thread_max_core_count = max(thread_max_core_count,
 							vreg->max_core_count);
 			thread_valid_sdelta |= (vreg->allow_core_count_adj
-							| vreg->allow_temp_adj);
+							| vreg->allow_temp_adj
+							| vreg->allow_boost);
 		}
 		if (thread_valid_sdelta) {
 			sdelta = devm_kzalloc(ctrl->dev, sizeof(*sdelta),
@@ -774,6 +780,13 @@ static int cpr3_regulator_init_cpr4(struct cpr3_controller *ctrl)
 			if (!sdelta->table)
 				return -ENOMEM;
 
+			sdelta->boost_table = devm_kcalloc(ctrl->dev,
+						ctrl->temp_band_count,
+						sizeof(*sdelta->boost_table),
+						GFP_KERNEL);
+			if (!sdelta->boost_table)
+				return -ENOMEM;
+
 			thread->aggr_corner.sdelta = sdelta;
 		}
 
@@ -793,6 +806,13 @@ static int cpr3_regulator_init_cpr4(struct cpr3_controller *ctrl)
 		if (!sdelta->table)
 			return -ENOMEM;
 
+		sdelta->boost_table = devm_kcalloc(ctrl->dev,
+					ctrl->temp_band_count,
+					sizeof(*sdelta->boost_table),
+					GFP_KERNEL);
+		if (!sdelta->boost_table)
+			return -ENOMEM;
+
 		ctrl->aggr_corner.sdelta = sdelta;
 	}
 
@@ -852,10 +872,18 @@ static int cpr3_controller_program_sdelta(struct cpr3_controller *ctrl)
 		/* cpr4_sdelta not defined for current aggregated corner */
 		return 0;
 
-	if (!sdelta->allow_core_count_adj && !sdelta->allow_temp_adj) {
+	if (ctrl->supports_hw_closed_loop && ctrl->cpr_enabled) {
+		cpr3_masked_write(ctrl, CPR4_REG_MARGIN_ADJ_CTL,
+			CPR4_MARGIN_ADJ_CTL_HW_CLOSED_LOOP_EN_MASK,
+			(ctrl->use_hw_closed_loop && !sdelta->allow_boost)
+			? CPR4_MARGIN_ADJ_CTL_HW_CLOSED_LOOP_ENABLE : 0);
+	}
+
+	if (!sdelta->allow_core_count_adj && !sdelta->allow_temp_adj
+		&& !sdelta->allow_boost) {
 		/*
-		 * Both per-online-core and per-temperature adjustments
-		 * are disabled for this aggregation corner
+		 * Per-online-core, per-temperature and voltage boost
+		 * adjustments are disabled for this aggregation corner.
 		 */
 		return 0;
 	}
@@ -872,25 +900,37 @@ static int cpr3_controller_program_sdelta(struct cpr3_controller *ctrl)
 
 	max_core_count = sdelta->max_core_count;
 
-	if (sdelta->allow_core_count_adj) {
-		/* Program TEMP_CORE0 to same margins as TEMP_CORE1 */
-		cpr3_write_temp_core_margin(ctrl,
-			CPR4_REG_MARGIN_TEMP_CORE(0), &sdelta->table[0]);
-	}
+	if (sdelta->allow_core_count_adj || sdelta->allow_temp_adj) {
+		if (sdelta->allow_core_count_adj) {
+			/* Program TEMP_CORE0 to same margins as TEMP_CORE1 */
+			cpr3_write_temp_core_margin(ctrl,
+				CPR4_REG_MARGIN_TEMP_CORE(0),
+				&sdelta->table[0]);
+		}
 
-	for (i = 0; i < max_core_count; i++) {
-		index = i * sdelta->temp_band_count;
-		/*
-		 * Program TEMP_COREi with voltage margin adjustments that need
-		 * to be applied when the number of cores becomes i.
-		 */
-		cpr3_write_temp_core_margin(ctrl,
-			CPR4_REG_MARGIN_TEMP_CORE(sdelta->allow_core_count_adj
+		for (i = 0; i < max_core_count; i++) {
+			index = i * sdelta->temp_band_count;
+			/*
+			 * Program TEMP_COREi with voltage margin adjustments
+			 * that need to be applied when the number of cores
+			 * becomes i.
+			 */
+			cpr3_write_temp_core_margin(ctrl,
+				CPR4_REG_MARGIN_TEMP_CORE(
+						sdelta->allow_core_count_adj
 						? i + 1 : max_core_count),
 						&sdelta->table[index]);
+		}
 	}
 
-	if (!sdelta->allow_core_count_adj) {
+	if (sdelta->allow_boost) {
+		/* Program only boost_num_cores row of SDELTA */
+		cpr3_write_temp_core_margin(ctrl,
+			CPR4_REG_MARGIN_TEMP_CORE(sdelta->boost_num_cores),
+					&sdelta->boost_table[0]);
+	}
+
+	if (!sdelta->allow_core_count_adj && !sdelta->allow_boost) {
 		cpr3_masked_write(ctrl, CPR4_REG_MISC,
 			CPR4_MISC_MARGIN_TABLE_ROW_SELECT_MASK,
 			max_core_count
@@ -901,13 +941,16 @@ static int cpr3_controller_program_sdelta(struct cpr3_controller *ctrl)
 		CPR4_MARGIN_ADJ_CTL_MAX_NUM_CORES_MASK
 		| CPR4_MARGIN_ADJ_CTL_CORE_ADJ_EN
 		| CPR4_MARGIN_ADJ_CTL_TEMP_ADJ_EN
-		| CPR4_MARGIN_ADJ_CTL_KV_MARGIN_ADJ_EN,
+		| CPR4_MARGIN_ADJ_CTL_KV_MARGIN_ADJ_EN
+		| CPR4_MARGIN_ADJ_CTL_BOOST_EN,
 		max_core_count << CPR4_MARGIN_ADJ_CTL_MAX_NUM_CORES_SHIFT
-		| (sdelta->allow_core_count_adj
+		| ((sdelta->allow_core_count_adj || sdelta->allow_boost)
 		? CPR4_MARGIN_ADJ_CTL_CORE_ADJ_EN : 0)
 		| (sdelta->allow_temp_adj ? CPR4_MARGIN_ADJ_CTL_TEMP_ADJ_EN : 0)
-		| (ctrl->use_hw_closed_loop
-		? CPR4_MARGIN_ADJ_CTL_KV_MARGIN_ADJ_EN : 0));
+		| ((ctrl->use_hw_closed_loop && !sdelta->allow_boost)
+		? CPR4_MARGIN_ADJ_CTL_KV_MARGIN_ADJ_EN : 0)
+		| (sdelta->allow_boost
+		?  CPR4_MARGIN_ADJ_CTL_BOOST_EN : 0));
 
 	/*
 	 * Ensure that all previous CPR register writes have completed before
@@ -2219,7 +2262,7 @@ static void cpr3_regulator_aggregate_sdelta(
 	struct cpr4_sdelta *aggr_sdelta, *sdelta;
 	int aggr_core_count, core_count, temp_band_count;
 	u32 aggr_index, index;
-	int i, j, sdelta_size, cap_steps;
+	int i, j, sdelta_size, cap_steps, adjust_sdelta;
 
 	aggr_sdelta = aggr_corner->sdelta;
 	sdelta = corner->sdelta;
@@ -2236,7 +2279,6 @@ static void cpr3_regulator_aggregate_sdelta(
 		aggr_sdelta->cap_volt = min(aggr_sdelta->cap_volt,
 						(corner->open_loop_volt -
 						aggr_corner->open_loop_volt));
-		aggr_corner->open_loop_volt = corner->open_loop_volt;
 
 		/* Clear old data in the sdelta table */
 		sdelta_size = aggr_sdelta->max_core_count
@@ -2256,6 +2298,23 @@ static void cpr3_regulator_aggregate_sdelta(
 					sdelta_size * sizeof(*sdelta->table));
 		}
 
+		if (sdelta->allow_boost) {
+			memcpy(aggr_sdelta->boost_table, sdelta->boost_table,
+				sdelta->temp_band_count
+				* sizeof(*sdelta->boost_table));
+			aggr_sdelta->boost_num_cores = sdelta->boost_num_cores;
+		} else if (aggr_sdelta->allow_boost) {
+			for (i = 0; i < aggr_sdelta->temp_band_count; i++) {
+				adjust_sdelta = (corner->open_loop_volt
+						- aggr_corner->open_loop_volt)
+						/ step_volt;
+				aggr_sdelta->boost_table[i] += adjust_sdelta;
+				aggr_sdelta->boost_table[i]
+					= min(aggr_sdelta->boost_table[i], 0);
+			}
+		}
+
+		aggr_corner->open_loop_volt = corner->open_loop_volt;
 		aggr_sdelta->allow_temp_adj = sdelta->allow_temp_adj;
 		aggr_sdelta->allow_core_count_adj
 					= sdelta->allow_core_count_adj;
@@ -2269,6 +2328,19 @@ static void cpr3_regulator_aggregate_sdelta(
 		aggr_sdelta->cap_volt = min(aggr_sdelta->cap_volt,
 						(aggr_corner->open_loop_volt
 						- corner->open_loop_volt));
+
+		if (sdelta->allow_boost) {
+			for (i = 0; i < aggr_sdelta->temp_band_count; i++) {
+				adjust_sdelta = (aggr_corner->open_loop_volt
+						- corner->open_loop_volt)
+						/ step_volt;
+				aggr_sdelta->boost_table[i] =
+					sdelta->boost_table[i] + adjust_sdelta;
+				aggr_sdelta->boost_table[i]
+					= min(aggr_sdelta->boost_table[i], 0);
+			}
+			aggr_sdelta->boost_num_cores = sdelta->boost_num_cores;
+		}
 	} else {
 		/*
 		 * Found another dominant regulator with same open-loop
@@ -2280,6 +2352,7 @@ static void cpr3_regulator_aggregate_sdelta(
 		 */
 		aggr_sdelta->cap_volt = 0;
 		aggr_sdelta->allow_core_count_adj = false;
+
 		if (aggr_sdelta->allow_temp_adj
 					&& sdelta->allow_temp_adj) {
 			aggr_core_count = aggr_sdelta->max_core_count - 1;
@@ -2296,9 +2369,21 @@ static void cpr3_regulator_aggregate_sdelta(
 		} else {
 			aggr_sdelta->allow_temp_adj = false;
 		}
+
+		if (sdelta->allow_boost) {
+			memcpy(aggr_sdelta->boost_table, sdelta->boost_table,
+				sdelta->temp_band_count
+				* sizeof(*sdelta->boost_table));
+			aggr_sdelta->boost_num_cores = sdelta->boost_num_cores;
+		}
 	}
 
-	if (aggr_sdelta->cap_volt && !aggr_sdelta->cap_volt == INT_MAX) {
+	/* Keep non-dominant clients boost enable state */
+	aggr_sdelta->allow_boost |= sdelta->allow_boost;
+	if (aggr_sdelta->allow_boost)
+		aggr_sdelta->allow_core_count_adj = false;
+
+	if (aggr_sdelta->cap_volt && !(aggr_sdelta->cap_volt == INT_MAX)) {
 		core_count = aggr_sdelta->max_core_count;
 		temp_band_count = aggr_sdelta->temp_band_count;
 		/*
@@ -2357,7 +2442,8 @@ static void cpr3_regulator_aggregate_corners(struct cpr3_corner *aggr_corner,
 	}
 
 	if (aggr_corner->sdelta && corner->sdelta
-		&& aggr_corner->sdelta->table) {
+		&& (aggr_corner->sdelta->table
+		|| aggr_corner->sdelta->boost_table)) {
 		cpr3_regulator_aggregate_sdelta(aggr_corner, corner, step_volt);
 	} else {
 		aggr_corner->open_loop_volt
@@ -2398,7 +2484,7 @@ static int _cpr3_regulator_update_ctrl_state(struct cpr3_controller *ctrl)
 	bool thread_valid;
 	int i, j, rc, new_volt, vdd_volt, dynamic_floor_volt, last_corner_volt;
 	u32 reg_last_measurement = 0, sdelta_size;
-	int *sdelta_table;
+	int *sdelta_table, *boost_table;
 
 	if (ctrl->ctrl_type == CPR_CTRL_TYPE_CPR4) {
 		rc = cpr3_ctrl_clear_cpr4_config(ctrl);
@@ -2443,9 +2529,15 @@ static int _cpr3_regulator_update_ctrl_state(struct cpr3_controller *ctrl)
 					* sizeof(*sdelta_table));
 		}
 
+		boost_table = sdelta->boost_table;
+		if (boost_table)
+			memset(boost_table, 0, sdelta->temp_band_count
+					* sizeof(*boost_table));
+
 		memset(sdelta, 0, sizeof(*sdelta));
 		sdelta->table = sdelta_table;
 		sdelta->cap_volt = INT_MAX;
+		sdelta->boost_table = boost_table;
 	}
 
 	/* Aggregate the requests of all threads */
@@ -2463,9 +2555,15 @@ static int _cpr3_regulator_update_ctrl_state(struct cpr3_controller *ctrl)
 						* sizeof(*sdelta_table));
 			}
 
+			boost_table = sdelta->boost_table;
+			if (boost_table)
+				memset(boost_table, 0, sdelta->temp_band_count
+						* sizeof(*boost_table));
+
 			memset(sdelta, 0, sizeof(*sdelta));
 			sdelta->table = sdelta_table;
 			sdelta->cap_volt = INT_MAX;
+			sdelta->boost_table = boost_table;
 		}
 
 		memset(&thread->aggr_corner, 0, sizeof(thread->aggr_corner));
@@ -2689,7 +2787,8 @@ static int _cpr3_regulator_update_ctrl_state(struct cpr3_controller *ctrl)
 
 	ctrl->aggr_corner = aggr_corner;
 
-	if (ctrl->allow_core_count_adj || ctrl->allow_temp_adj) {
+	if (ctrl->allow_core_count_adj || ctrl->allow_temp_adj
+		|| ctrl->allow_boost) {
 		rc = cpr3_controller_program_sdelta(ctrl);
 		if (rc) {
 			cpr3_err(ctrl, "failed to program sdelta, rc=%d\n", rc);
@@ -5135,7 +5234,9 @@ int cpr3_regulator_resume(struct cpr3_controller *ctrl)
  */
 static int cpr3_regulator_validate_controller(struct cpr3_controller *ctrl)
 {
-	int i;
+	struct cpr3_thread *thread;
+	struct cpr3_regulator *vreg;
+	int i, j, allow_boost_vreg_count = 0;
 
 	if (!ctrl->vdd_regulator) {
 		cpr3_err(ctrl, "vdd regulator missing\n");
@@ -5162,6 +5263,24 @@ static int cpr3_regulator_validate_controller(struct cpr3_controller *ctrl)
 		}
 	}
 
+	for (i = 0; i < ctrl->thread_count; i++) {
+		thread = &ctrl->thread[i];
+		for (j = 0; j < thread->vreg_count; j++) {
+			vreg = &thread->vreg[j];
+			if (vreg->allow_boost)
+				allow_boost_vreg_count++;
+		}
+	}
+
+	if (allow_boost_vreg_count > 1) {
+		/*
+		 * Boost feature is not allowed to be used for more
+		 * than one CPR3 regulator of a CPR3 controller.
+		 */
+		cpr3_err(ctrl, "Boost feature is enabled for more than one regulator\n");
+		return -EINVAL;
+	}
+
 	return 0;
 }
 
diff --git a/drivers/regulator/cpr3-regulator.h b/drivers/regulator/cpr3-regulator.h
index a5ba05b5ace4..4e098e7d7df1 100644
--- a/drivers/regulator/cpr3-regulator.h
+++ b/drivers/regulator/cpr3-regulator.h
@@ -71,6 +71,14 @@ struct cpr3_fuse_param {
  *			values correspond to a reduction in voltage and negative
  *			value correspond to an increase (this follows the SDELTA
  *			register semantics).
+ * @allow_boost:	Voltage boost allowed.
+ * @boost_num_cores:	The number of online cores at which the boost voltage
+ *			adjustments will be applied
+ * @boost_table:	SDELTA table with boost voltage adjustments of size
+ *			temp_band_count. Each element has units of VDD supply
+ *			steps. Positive values correspond to a reduction in
+ *			voltage and negative value correspond to an increase
+ *			(this follows the SDELTA register semantics).
  */
 struct cpr4_sdelta {
 	bool	allow_core_count_adj;
@@ -79,6 +87,9 @@ struct cpr4_sdelta {
 	int	temp_band_count;
 	int	cap_volt;
 	int	*table;
+	bool	allow_boost;
+	int	boost_num_cores;
+	int	*boost_table;
 };
 
 /**
@@ -241,6 +252,7 @@ struct cpr3_corner {
  *			regulator.
  * @max_core_count:	Maximum number of cores considered for core count
  *			adjustment logic.
+ * @allow_boost:	Voltage boost allowed for this regulator.
  *
  * This structure contains both configuration and runtime state data.  The
  * elements current_corner, last_closed_loop_corner, aggregated, debug_corner,
@@ -294,6 +306,7 @@ struct cpr3_regulator {
 	bool			allow_core_count_adj;
 	bool			allow_temp_adj;
 	int			max_core_count;
+	bool			allow_boost;
 };
 
 /**
@@ -553,6 +566,7 @@ struct cpr3_aging_sensor_info {
  * @allow_core_count_adj: Core count adjustments are allowed for this controller
  * @allow_temp_adj:	Temperature based adjustments are allowed for
  *			this controller
+ * @allow_boost:	Voltage boost allowed for this controller.
  * @temp_band_count:	Number of temperature bands used for temperature based
  *			adjustment logic
  * @temp_points:	Array of temperature points in decidegrees Celsius used
@@ -649,6 +663,7 @@ struct cpr3_controller {
 	bool			use_dynamic_step_quot;
 	bool			allow_core_count_adj;
 	bool			allow_temp_adj;
+	bool			allow_boost;
 	int			temp_band_count;
 	int			*temp_points;
 	u32			temp_sensor_id_start;
diff --git a/drivers/regulator/cpr4-apss-regulator.c b/drivers/regulator/cpr4-apss-regulator.c
index 02242160f3f9..5b8104da7c10 100644
--- a/drivers/regulator/cpr4-apss-regulator.c
+++ b/drivers/regulator/cpr4-apss-regulator.c
@@ -51,6 +51,9 @@
  * @speed_bin:		Application processor speed bin fuse parameter value for
  *			the given chip
  * @cpr_fusing_rev:	CPR fusing revision fuse parameter value
+ * @boost_cfg:		CPR boost configuration fuse parameter value
+ * @boost_voltage:	CPR boost voltage fuse parameter value (raw, not
+ *			converted to a voltage)
  *
  * This struct holds the values for all of the fuses read from memory.
  */
@@ -61,6 +64,8 @@ struct cpr4_msmtitanium_apss_fuses {
 	u64	quot_offset[MSMTITANIUM_APSS_FUSE_CORNERS];
 	u64	speed_bin;
 	u64	cpr_fusing_rev;
+	u64	boost_cfg;
+	u64	boost_voltage;
 };
 
 /*
@@ -140,6 +145,16 @@ static const struct cpr3_fuse_param msmtitanium_apss_speed_bin_param[] = {
 	{},
 };
 
+static const struct cpr3_fuse_param msmtitanium_cpr_boost_fuse_cfg_param[] = {
+	{36, 43, 45},
+	{},
+};
+
+static const struct cpr3_fuse_param msmtitanium_apss_boost_fuse_volt_param[] = {
+	{71, 0, 5},
+	{},
+};
+
 /*
  * Open loop voltage fuse reference voltages in microvolts for MSMTITANIUM
  */
@@ -162,6 +177,22 @@ static const int msmtitanium_apss_fuse_ref_volt
 #define MSMTITANIUM_APSS_MAX_TEMP_POINTS	3
 #define MSMTITANIUM_APSS_TEMP_SENSOR_ID_START	4
 #define MSMTITANIUM_APSS_TEMP_SENSOR_ID_END	13
+/*
+ * Boost voltage fuse reference and ceiling voltages in microvolts for
+ * MSMTITANIUM.
+ */
+#define MSMTITANIUM_APSS_BOOST_FUSE_REF_VOLT	1140000
+#define MSMTITANIUM_APSS_BOOST_CEILING_VOLT	1140000
+#define MSMTITANIUM_APSS_BOOST_FLOOR_VOLT	900000
+#define MAX_BOOST_CONFIG_FUSE_VALUE		8
+
+#define MSMTITANIUM_APSS_CPR_SDELTA_CORE_COUNT	15
+
+/*
+ * Array of integer values mapped to each of the boost config fuse values to
+ * indicate boost enable/disable status.
+ */
+static bool boost_fuse[MAX_BOOST_CONFIG_FUSE_VALUE] = {0, 1, 1, 1, 1, 1, 1, 1};
 
 /**
  * cpr4_msmtitanium_apss_read_fuse_data() - load APSS specific fuse parameter values
@@ -238,6 +269,26 @@ static int cpr4_msmtitanium_apss_read_fuse_data(struct cpr3_regulator *vreg)
 		}
 	}
 
+	rc = cpr3_read_fuse_param(base, msmtitanium_cpr_boost_fuse_cfg_param,
+				&fuse->boost_cfg);
+	if (rc) {
+		cpr3_err(vreg, "Unable to read CPR boost config fuse, rc=%d\n",
+			rc);
+		return rc;
+	}
+	cpr3_info(vreg, "Voltage boost fuse config = %llu boost = %s\n",
+			fuse->boost_cfg, boost_fuse[fuse->boost_cfg]
+			? "enable" : "disable");
+
+	rc = cpr3_read_fuse_param(base,
+				msmtitanium_apss_boost_fuse_volt_param,
+				&fuse->boost_voltage);
+	if (rc) {
+		cpr3_err(vreg, "failed to read boost fuse voltage, rc=%d\n",
+			rc);
+		return rc;
+	}
+
 	vreg->fuse_combo = fuse->cpr_fusing_rev + 8 * fuse->speed_bin;
 	if (vreg->fuse_combo >= CPR4_MSMTITANIUM_APSS_FUSE_COMBO_COUNT) {
 		cpr3_err(vreg, "invalid CPR fuse combo = %d found\n",
@@ -861,6 +912,13 @@ static int cpr4_apss_parse_core_count_temp_voltage_adj(
 			return -EINVAL;
 		}
 
+		if (vreg->max_core_count <= 0 || vreg->max_core_count
+				> MSMTITANIUM_APSS_CPR_SDELTA_CORE_COUNT) {
+			cpr3_err(vreg, "qcom,max-core-count has invalid value = %d\n",
+				vreg->max_core_count);
+			return -EINVAL;
+		}
+
 		vreg->allow_core_count_adj = true;
 		ctrl->allow_core_count_adj = true;
 	}
@@ -945,6 +1003,157 @@ done:
 }
 
 /**
+ * cpr4_apss_parse_boost_properties() - parse configuration data for boost
+ *		voltage adjustment for CPR3 regulator from device tree.
+ * @vreg:	Pointer to the CPR3 regulator
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_apss_parse_boost_properties(struct cpr3_regulator *vreg)
+{
+	struct cpr3_controller *ctrl = vreg->thread->ctrl;
+	struct cpr4_msmtitanium_apss_fuses *fuse = vreg->platform_fuses;
+	struct cpr3_corner *corner;
+	int i, boost_voltage, final_boost_volt, rc = 0;
+	int *boost_table = NULL, *boost_temp_adj = NULL;
+	int boost_voltage_adjust = 0, boost_num_cores = 0;
+	u32 boost_allowed = 0;
+
+	if (!boost_fuse[fuse->boost_cfg])
+		/* Voltage boost is disabled in fuse */
+		return 0;
+
+	if (of_find_property(vreg->of_node, "qcom,allow-boost", NULL)) {
+		rc = cpr3_parse_array_property(vreg, "qcom,allow-boost", 1,
+				&boost_allowed);
+		if (rc)
+			return rc;
+	}
+
+	if (!boost_allowed) {
+		/* Voltage boost is not enabled for this regulator */
+		return 0;
+	}
+
+	boost_voltage = cpr3_convert_open_loop_voltage_fuse(
+				MSMTITANIUM_APSS_BOOST_FUSE_REF_VOLT,
+				MSMTITANIUM_APSS_FUSE_STEP_VOLT,
+				fuse->boost_voltage,
+				MSMTITANIUM_APSS_VOLTAGE_FUSE_SIZE);
+
+	/* Log boost voltage value for debugging purposes. */
+	cpr3_info(vreg, "Boost open-loop=%7d uV\n", boost_voltage);
+
+	if (of_find_property(vreg->of_node,
+			"qcom,cpr-boost-voltage-fuse-adjustment", NULL)) {
+		rc = cpr3_parse_array_property(vreg,
+			"qcom,cpr-boost-voltage-fuse-adjustment",
+			1, &boost_voltage_adjust);
+		if (rc) {
+			cpr3_err(vreg, "qcom,cpr-boost-voltage-fuse-adjustment reading failed, rc=%d\n",
+				rc);
+			return rc;
+		}
+
+		boost_voltage += boost_voltage_adjust;
+		/* Log boost voltage value for debugging purposes. */
+		cpr3_info(vreg, "Adjusted boost open-loop=%7d uV\n",
+			boost_voltage);
+	}
+
+	/* Limit boost voltage value between ceiling and floor voltage limits */
+	boost_voltage = min(boost_voltage, MSMTITANIUM_APSS_BOOST_CEILING_VOLT);
+	boost_voltage = max(boost_voltage, MSMTITANIUM_APSS_BOOST_FLOOR_VOLT);
+
+	/*
+	 * The boost feature can only be used for the highest voltage corner.
+	 * Also, keep core-count adjustments disabled when the boost feature
+	 * is enabled.
+	 */
+	corner = &vreg->corner[vreg->corner_count - 1];
+	if (!corner->sdelta) {
+		/*
+		 * If core-count/temp adjustments are not defined, the cpr4
+		 * sdelta for this corner will not be allocated. Allocate it
+		 * here for boost configuration.
+		 */
+		corner->sdelta = devm_kzalloc(ctrl->dev,
+					sizeof(*corner->sdelta), GFP_KERNEL);
+		if (!corner->sdelta)
+			return -ENOMEM;
+	}
+	corner->sdelta->temp_band_count = ctrl->temp_band_count;
+
+	rc = of_property_read_u32(vreg->of_node, "qcom,cpr-num-boost-cores",
+				&boost_num_cores);
+	if (rc) {
+		cpr3_err(vreg, "qcom,cpr-num-boost-cores reading failed, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	if (boost_num_cores <= 0
+		|| boost_num_cores > MSMTITANIUM_APSS_CPR_SDELTA_CORE_COUNT) {
+		cpr3_err(vreg, "Invalid boost number of cores = %d\n",
+			boost_num_cores);
+		return -EINVAL;
+	}
+	corner->sdelta->boost_num_cores = boost_num_cores;
+
+	boost_table = devm_kcalloc(ctrl->dev, corner->sdelta->temp_band_count,
+					sizeof(*boost_table), GFP_KERNEL);
+	if (!boost_table)
+		return -ENOMEM;
+
+	if (of_find_property(vreg->of_node,
+				"qcom,cpr-boost-temp-adjustment", NULL)) {
+		boost_temp_adj = kcalloc(corner->sdelta->temp_band_count,
+					sizeof(*boost_temp_adj), GFP_KERNEL);
+		if (!boost_temp_adj)
+			return -ENOMEM;
+
+		rc = cpr3_parse_array_property(vreg,
+				"qcom,cpr-boost-temp-adjustment",
+				corner->sdelta->temp_band_count,
+				boost_temp_adj);
+		if (rc) {
+			cpr3_err(vreg, "qcom,cpr-boost-temp-adjustment reading failed, rc=%d\n",
+				rc);
+			goto done;
+		}
+	}
+
+	for (i = 0; i < corner->sdelta->temp_band_count; i++) {
+		/* Apply static adjustments to boost voltage */
+		final_boost_volt = boost_voltage + (boost_temp_adj == NULL
+						? 0 : boost_temp_adj[i]);
+		/*
+		 * Limit final adjusted boost voltage value between ceiling
+		 * and floor voltage limits
+		 */
+		final_boost_volt = min(final_boost_volt,
+					MSMTITANIUM_APSS_BOOST_CEILING_VOLT);
+		final_boost_volt = max(final_boost_volt,
+					MSMTITANIUM_APSS_BOOST_FLOOR_VOLT);
+
+		boost_table[i] = (corner->open_loop_volt - final_boost_volt)
+					/ ctrl->step_volt;
+		cpr3_debug(vreg, "Adjusted boost voltage margin for temp band %d = %d steps\n",
+			i, boost_table[i]);
+	}
+
+	corner->ceiling_volt = MSMTITANIUM_APSS_BOOST_CEILING_VOLT;
+	corner->sdelta->boost_table = boost_table;
+	corner->sdelta->allow_boost = true;
+	corner->sdelta->allow_core_count_adj = false;
+	vreg->allow_boost = true;
+	ctrl->allow_boost = true;
+done:
+	kfree(boost_temp_adj);
+	return rc;
+}
+
+/**
  * cpr4_apss_init_regulator() - perform all steps necessary to initialize the
  *		configuration data for a CPR3 regulator
  * @vreg:		Pointer to the CPR3 regulator
@@ -1014,6 +1223,14 @@ static int cpr4_apss_init_regulator(struct cpr3_regulator *vreg)
 			 rc);
 		return rc;
 	}
+
+	rc = cpr4_apss_parse_boost_properties(vreg);
+	if (rc) {
+		cpr3_err(vreg, "unable to parse boost adjustments, rc=%d\n",
+			 rc);
+		return rc;
+	}
+
 	cpr4_apss_print_settings(vreg);
 
 	return rc;