Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 72265a6d authored by Osvaldo Banuelos's avatar Osvaldo Banuelos
Browse files

regulator: cpr3-regulator: add support for LDO maximum headroom 



In order to maintain optimum operability of the LDO hardware it is
necessary to impose a maximum voltage difference between the input
and output voltage of the LDOs. Add support for a device tree property
which specifies this maximum voltage difference and enforce it when
configuring the LDO hardware whenever a CPR corner change request
is handled.

Change-Id: Ic58cb16714109b5845d1ed5755a57c62078683b0
Signed-off-by: default avatarOsvaldo Banuelos <osvaldob@codeaurora.org>
parent bdac6adb

Documentation/devicetree/bindings/regulator/cpr3-hmss-regulator.txt

+22 −4
Original line number Diff line number Diff line
@@ -79,6 +79,12 @@ HMSS specific properties: 
		    which may be used as the ceiling for the corner.  If this

		    property is not specified, then a value of 0 is assumed.



- qcom,system-supply-max-voltage

	Usage:      required if qcom,vdd-threadN-ldo-supply is specified for any

		    CPR3 regulator managed by any CPR3 thread of this controller.

	Value type: <u32>

	Definition: Maximum voltage setpoint for the system-supply regulator.



- qcom,cpr-up-down-delay-time

	Usage:      required

	Value type: <u32>
@@ -174,7 +180,7 @@ HMSS specific properties: 
		    given regulator type.  For HMSS the maximum supported value

		    is 2.



- qcom,ldo-headroom-voltage

- qcom,ldo-min-headroom-voltage

	Usage:      required if qcom,vdd-threadN-ldo-supply is specified for the

		    CPR3 thread containing this CPR3 regulator and this CPR3

		    regulator needs to manage the cluster LDO state.
@@ -182,6 +188,15 @@ HMSS specific properties: 
	Definition: Voltage in microvolts required between the VDD_APCC voltage

		    and the LDO output in order for the LDO to be operational.



- qcom,ldo-max-headroom-voltage

	Usage:      required if qcom,vdd-threadN-ldo-supply is specified for the

		    CPR3 thread containing this CPR3 regulator and this CPR3

		    regulator needs to manage the cluster LDO state.

	Value type: <u32>

	Definition: Maximum voltage difference in microvolts between the vdd-supply

		    voltage and the LDO output voltage in order for active LDO mode

		    to be operational.



- qcom,ldo-adjust-voltage

	Usage:      optional

	Value type: <u32>
@@ -189,7 +204,7 @@ HMSS specific properties: 
		    output and CPU.



- qcom,ldo-max-voltage

	Usage:      required if qcom,ldo-headroom-voltage is specified for this

	Usage:      required if qcom,ldo-min-headroom-voltage is specified for this

		    CPR3 regulator.

	Value type: <u32>

	Definition: Voltage in microvolts which represents the maximum
@@ -248,6 +263,7 @@ apcc_cpr: cpr3-ctrl@99e8000 { 
	qcom,apm-ctrl = <&apc_apm>;

	qcom,apm-threshold-voltage = <850000>;

	qcom,apm-hysteresis-voltage = <5000>;

	qcom,system-supply-max-voltage = <1015000>;



	vdd-supply = <&pm8994_s11>;

	qcom,voltage-step = <5000>;
@@ -280,7 +296,8 @@ apcc_cpr: cpr3-ctrl@99e8000 { 
			qcom,cpr-fuse-combos = <1>;

			qcom,cpr-corners = <19>;



			qcom,ldo-headroom-voltage = <150000>;

			qcom,ldo-min-headroom-voltage = <150000>;

			qcom,ldo-max-headroom-voltage = <470000>;

			qcom,ldo-max-voltage = <805000>;



			qcom,cpr-corner-fmax-map = <1 2 6 11 19>;
@@ -408,7 +425,8 @@ apcc_cpr: cpr3-ctrl@99e8000 { 
			qcom,cpr-fuse-combos = <1>;

			qcom,cpr-corners = <18>;



			qcom,ldo-headroom-voltage = <150000>;

			qcom,ldo-min-headroom-voltage = <150000>;

			qcom,ldo-max-headroom-voltage = <470000>;

			qcom,ldo-max-voltage = <805000>;



			qcom,cpr-corner-fmax-map = <1 3 5 11 18>;

arch/arm/boot/dts/qcom/msm8996-regulator.dtsi

+5 −2
Original line number Diff line number Diff line
@@ -574,6 +574,7 @@ 
		qcom,apm-ctrl = <&apc_apm>;

		qcom,apm-threshold-voltage = <850000>;

		qcom,apm-hysteresis-voltage = <5000>;

		qcom,system-supply-max-voltage = <1015000>;



		vdd-supply = <&pm8994_s11>;

		qcom,voltage-step = <5000>;
@@ -612,7 +613,8 @@ 
					/* Speed bin 1 */

					<13 13 13 13 13 13 13 13>;



				qcom,ldo-headroom-voltage = <150000>;

				qcom,ldo-min-headroom-voltage = <150000>;

				qcom,ldo-max-headroom-voltage = <470000>;

				qcom,ldo-max-voltage = <890000>;



				qcom,cpr-corner-fmax-map =
@@ -947,7 +949,8 @@ 
					/* Speed bin 1 */

					<21 21 21 21 21 21 21 21>;



				qcom,ldo-headroom-voltage = <150000>;

				qcom,ldo-min-headroom-voltage = <150000>;

				qcom,ldo-max-headroom-voltage = <470000>;

				qcom,ldo-max-voltage = <890000>;



				qcom,cpr-corner-fmax-map =

arch/arm/boot/dts/qcom/msm8996-v2.dtsi

+0 −2
Original line number Diff line number Diff line
@@ -109,7 +109,6 @@ 
	qcom,cpr-fuse-combos = <4>;

	qcom,cpr-corners = <19>;



	qcom,ldo-headroom-voltage = <150000>;

	qcom,ldo-max-voltage = <805000>;



	qcom,cpr-corner-fmax-map = <1 2 6 11 19>;
@@ -227,7 +226,6 @@ 
	qcom,cpr-fuse-combos = <4>;

	qcom,cpr-corners = <18>;



	qcom,ldo-headroom-voltage = <150000>;

	qcom,ldo-max-voltage = <805000>;



	qcom,cpr-corner-fmax-map = <1 3 5 11 18>;

drivers/regulator/cpr3-hmss-regulator.c

+26 −6
Original line number Diff line number Diff line
@@ -1279,7 +1279,7 @@ static int cpr3_hmss_kvreg_init(struct cpr3_regulator *vreg) 


	if (!of_find_property(ctrl->dev->of_node, kvreg_name_buf , NULL))

		return 0;

	else if (!of_find_property(node, "qcom,ldo-headroom-voltage", NULL))

	else if (!of_find_property(node, "qcom,ldo-min-headroom-voltage", NULL))

		return 0;



	scnprintf(kvreg_name_buf, MAX_KVREG_NAME_SIZE, "vdd-thread%d-ldo", id);
@@ -1307,10 +1307,23 @@ static int cpr3_hmss_kvreg_init(struct cpr3_regulator *vreg) 
		return rc;

	}



	rc = of_property_read_u32(node, "qcom,ldo-headroom-voltage",

				&vreg->ldo_headroom_volt);

	if (!ctrl->system_supply_max_volt) {

		cpr3_err(ctrl, "system-supply max voltage must be specified\n");

		return -EINVAL;

	}



	rc = of_property_read_u32(node, "qcom,ldo-min-headroom-voltage",

				&vreg->ldo_min_headroom_volt);

	if (rc) {

		cpr3_err(vreg, "error reading qcom,ldo-headroom-voltage, rc=%d\n",

		cpr3_err(vreg, "error reading qcom,ldo-min-headroom-voltage, rc=%d\n",

			rc);

		return rc;

	}



	rc = of_property_read_u32(node, "qcom,ldo-max-headroom-voltage",

				  &vreg->ldo_max_headroom_volt);

	if (rc) {

		cpr3_err(vreg, "error reading qcom,ldo-max-headroom-voltage, rc=%d\n",

			 rc);

		return rc;

	}
@@ -1343,8 +1356,9 @@ static int cpr3_hmss_kvreg_init(struct cpr3_regulator *vreg) 
	vreg->ldo_mode_allowed = !of_property_read_bool(node,

							"qcom,ldo-disable");



	cpr3_info(vreg, "LDO headroom=%d uV, LDO adj=%d uV, LDO mode=%s, LDO retention=%d uV\n",

		  vreg->ldo_headroom_volt,

	cpr3_info(vreg, "LDO min headroom=%d uV, LDO max headroom=%d uV, LDO adj=%d uV, LDO mode=%s, LDO retention=%d uV\n",

		  vreg->ldo_min_headroom_volt,

		  vreg->ldo_max_headroom_volt,

		  vreg->ldo_adjust_volt,

		  vreg->ldo_mode_allowed ? "allowed" : "disallowed",

		  vreg->ldo_ret_volt);
@@ -1598,6 +1612,12 @@ static int cpr3_hmss_init_controller(struct cpr3_controller *ctrl) 
		return rc;

	}





	/* No error check since this is an optional property. */

	of_property_read_u32(ctrl->dev->of_node,

			     "qcom,system-supply-max-voltage",

			     &ctrl->system_supply_max_volt);



	/* No error check since this is an optional property. */

	of_property_read_u32(ctrl->dev->of_node, "qcom,cpr-clock-throttling",

			&ctrl->proc_clock_throttle);

drivers/regulator/cpr3-regulator.c

+133 −29
Original line number Diff line number Diff line
@@ -782,7 +782,7 @@ static int cpr3_regulator_config_ldo_retention(struct cpr3_regulator *vreg, 


	}



	mode = floor_volt >= retention_volt + vreg->ldo_headroom_volt

	mode = floor_volt >= retention_volt + vreg->ldo_min_headroom_volt

		? LDO_MODE : BHS_MODE;



	rc = regulator_allow_bypass(ldo_ret_reg, mode);
@@ -811,7 +811,7 @@ static int cpr3_regulator_set_bhs_mode(struct cpr3_regulator *vreg, 
	struct regulator *ldo_reg = vreg->ldo_regulator;

	int bhs_volt, rc;



	bhs_volt = vdd_volt - vreg->ldo_headroom_volt;

	bhs_volt = vdd_volt - vreg->ldo_min_headroom_volt;

	if (bhs_volt > vreg->ldo_max_volt) {

		cpr3_debug(vreg, "limited to LDO output of %d uV when switching to BHS mode\n",

			   vreg->ldo_max_volt);
@@ -839,13 +839,18 @@ static int cpr3_regulator_set_bhs_mode(struct cpr3_regulator *vreg, 


/**

 * cpr3_regulator_config_vreg_ldo() - configure the voltage and bypass state for

 *		the LDO regulator associated with a single CPR3 regulator

 *		the LDO regulator associated with a single CPR3 regulator.

 *

 * @vreg:		Pointer to the CPR3 regulator

 * @vdd_floor_volt:	Last known aggregated floor voltage in microvolts for

 *			the VDD supply

 * @vdd_ceiling_volt:	Last known aggregated ceiling voltage in microvolts for

 *			the VDD supply

 * @vdd_volt:		Last known voltage in microvolts for the VDD supply

 * @last_volt:		Last known voltage in microvolts for the VDD supply

 * @apm_crossing:	Flag indicating if an APM reconfiguration is taking

 *			place as a result of a VDD voltage scale request and

 *			the VDD supply is at the crossover voltage

 * @new_volt:		New voltage in microvolts that VDD needs to end up at

 *

 * This function performs all relevant LDO or BHS configurations if an LDO

 * regulator is specified.
@@ -854,10 +859,53 @@ static int cpr3_regulator_set_bhs_mode(struct cpr3_regulator *vreg, 
 */

static int cpr3_regulator_config_vreg_ldo(struct cpr3_regulator *vreg,

			  int vdd_floor_volt, int vdd_ceiling_volt,

			     int vdd_volt)

			  int last_volt, bool apm_crossing, int new_volt)

{

	struct cpr3_controller *ctrl = vreg->thread->ctrl;

	struct regulator *ldo_reg = vreg->ldo_regulator;

	int rc, ldo_volt, bhs_volt, max_volt;

	struct cpr3_corner *current_corner;

	enum msm_apm_supply apm_mode;

	int rc, ldo_volt, final_ldo_volt, bhs_volt, max_volt, safe_volt;



	if (apm_crossing) {

		if (!vreg->vreg_enabled || vreg->current_corner

		    == CPR3_REGULATOR_CORNER_INVALID)

			return 0;



		/*

		 * Guarantee LDO maximum headroom is not

		 * violated when the APM is switched to the

		 * system-supply source.

		 */

		current_corner = &vreg->corner[vreg->current_corner];

		if (vreg->ldo_regulator_bypass == LDO_MODE) {

			apm_mode = msm_apm_get_supply(ctrl->apm);

			if (apm_mode < 0) {

				cpr3_err(ctrl, "APM get supply failed, rc=%d\n",

					 apm_mode);

				return apm_mode;

			}



			if (apm_mode == ctrl->apm_high_supply &&

			    new_volt < ctrl->apm_threshold_volt) {

				safe_volt = max(current_corner->open_loop_volt

						- vreg->ldo_adjust_volt,

						ctrl->system_supply_max_volt

						- vreg->ldo_max_headroom_volt);

				max_volt = min(ctrl->system_supply_max_volt,

					       vreg->ldo_max_volt);



				rc = regulator_set_voltage(ldo_reg, safe_volt,

							   max_volt);

				if (rc) {

					cpr3_err(vreg, "regulator_set_voltage(ldo) == %d failed, rc=%d\n",

						 safe_volt, rc);

					return rc;

				}

			}

		}

		return 0;

	}



	rc = cpr3_regulator_config_ldo_retention(vreg, vdd_floor_volt);

	if (rc)
@@ -867,34 +915,55 @@ static int cpr3_regulator_config_vreg_ldo(struct cpr3_regulator *vreg, 
	    == CPR3_REGULATOR_CORNER_INVALID)

		return 0;



	ldo_volt = vreg->corner[vreg->current_corner].open_loop_volt

	current_corner = &vreg->corner[vreg->current_corner];

	ldo_volt = current_corner->open_loop_volt

		- vreg->ldo_adjust_volt;



	bhs_volt = last_volt - vreg->ldo_min_headroom_volt;

	max_volt = min(vdd_ceiling_volt, vreg->ldo_max_volt);



	if (vdd_floor_volt >= ldo_volt + vreg->ldo_headroom_volt) {

	if (vdd_floor_volt >= ldo_volt + vreg->ldo_min_headroom_volt &&

	    ldo_volt >= ctrl->system_supply_max_volt -

	    vreg->ldo_max_headroom_volt &&

	    bhs_volt >= ctrl->system_supply_max_volt -

	    vreg->ldo_max_headroom_volt) {

		/* LDO minimum and maximum headrooms satisfied */

		apm_mode = msm_apm_get_supply(ctrl->apm);

		if (apm_mode < 0) {

			cpr3_err(ctrl, "APM get supply failed, rc=%d\n",

				 apm_mode);

			return apm_mode;

		}



		if (vreg->ldo_regulator_bypass == BHS_MODE) {

			if (ldo_volt > vreg->ldo_max_volt) {

				cpr3_debug(vreg, "cannot support LDO mode with ldo_volt=%d uV\n",

					   ldo_volt);

				return 0;

			}



			/*

			 * BHS to LDO transition. Configure LDO output

			 * to min(max LDO output, VDD - LDO headroom)

			 * voltage then switch the regulator mode.

			 */

			bhs_volt = vdd_volt - vreg->ldo_headroom_volt;

			if (bhs_volt > vreg->ldo_max_volt) {

				cpr3_debug(vreg, "limiting bhs_volt=%d uV to %d uV\n",

					   bhs_volt, vreg->ldo_max_volt);

				bhs_volt = vreg->ldo_max_volt;

			}

			 * voltage if APM is on high supply source or

			 * min(max(system-supply ceiling - LDO max headroom,

			 * VDD - LDO headroom), max LDO output) if

			 * APM is on low supply source, then switch

			 * regulator mode.

			 */

			if (apm_mode == ctrl->apm_high_supply)

				safe_volt = min(vreg->ldo_max_volt, bhs_volt);

			else

				safe_volt =

					min(max(ctrl->system_supply_max_volt -

						vreg->ldo_max_headroom_volt,

						bhs_volt),

					    vreg->ldo_max_volt);



			rc = regulator_set_voltage(ldo_reg, bhs_volt, max_volt);

			rc = regulator_set_voltage(ldo_reg, safe_volt,

						   max_volt);

			if (rc) {

				cpr3_err(vreg, "regulator_set_voltage(ldo) == %d failed, rc=%d\n",

					 bhs_volt, rc);

					 safe_volt, rc);

				return rc;

			}
@@ -908,15 +977,22 @@ static int cpr3_regulator_config_vreg_ldo(struct cpr3_regulator *vreg, 
		}



		/* Configure final LDO output voltage */

		rc = regulator_set_voltage(ldo_reg, ldo_volt, max_volt);

		if (apm_mode == ctrl->apm_high_supply)

			final_ldo_volt = max(ldo_volt,

					     vdd_ceiling_volt -

					     vreg->ldo_max_headroom_volt);

		else

			final_ldo_volt = ldo_volt;



		rc = regulator_set_voltage(ldo_reg, final_ldo_volt, max_volt);

		if (rc) {

			cpr3_err(vreg, "regulator_set_voltage(ldo) == %d failed, rc=%d\n",

				 ldo_volt, rc);

				 final_ldo_volt, rc);

			return rc;

		}

	} else {

		if (vreg->ldo_regulator_bypass == LDO_MODE) {

			rc = cpr3_regulator_set_bhs_mode(vreg, vdd_volt,

			rc = cpr3_regulator_set_bhs_mode(vreg, last_volt,

							vdd_ceiling_volt);

			if (rc)

				return rc;
@@ -935,13 +1011,17 @@ static int cpr3_regulator_config_vreg_ldo(struct cpr3_regulator *vreg, 
 *			the VDD supply

 * @vdd_ceiling_volt:	Last known aggregated ceiling voltage in microvolts for

 *			the VDD supply

 * @vdd_volt:		Last known voltage in microvolts for the VDD supply

 * @last_volt:		Last known voltage in microvolts for the VDD supply

 * @apm_crossing:	Flag indicating if an APM reconfiguration is taking

 *			place as a result of a VDD voltage scale request and

 *			the VDD supply is at the crossover voltage

 * @new_volt:		New voltage in microvolts that VDD needs to end up at

 *

 * Return: 0 on success, errno on failure

 */

static int cpr3_regulator_config_ldo(struct cpr3_controller *ctrl,

			     int vdd_floor_volt, int vdd_ceiling_volt,

			     int vdd_volt)

			     int last_volt, bool apm_crossing, int new_volt)

{

	struct cpr3_regulator *vreg;

	int i, j, rc;
@@ -954,7 +1034,8 @@ static int cpr3_regulator_config_ldo(struct cpr3_controller *ctrl, 
				continue;



			rc = cpr3_regulator_config_vreg_ldo(vreg,

				vdd_floor_volt, vdd_ceiling_volt, vdd_volt);

					vdd_floor_volt, vdd_ceiling_volt,

					last_volt, apm_crossing, new_volt);

			if (rc)

				return rc;

		}
@@ -999,6 +1080,18 @@ static int cpr3_regulator_scale_vdd_voltage(struct cpr3_controller *ctrl, 
		apm_crossing = true;



	if (apm_crossing) {

		if (new_volt < last_volt) {

			/* Decreasing VDD voltage */

			rc = cpr3_regulator_config_ldo(ctrl, apm_volt,

						       last_max_volt, last_volt,

						       false, apm_volt);

			if (rc) {

				cpr3_err(ctrl, "unable to configure LDO state, rc=%d\n",

					 rc);

				return rc;

			}

		}



		rc = regulator_set_voltage(vdd, apm_volt, apm_volt);

		if (rc) {

			cpr3_err(ctrl, "regulator_set_voltage(vdd) == %d failed, rc=%d\n",
@@ -1006,6 +1099,15 @@ static int cpr3_regulator_scale_vdd_voltage(struct cpr3_controller *ctrl, 
			return rc;

		}



		rc = cpr3_regulator_config_ldo(ctrl, aggr_corner->floor_volt,

					       last_max_volt, apm_volt, true,

					       new_volt);

		if (rc) {

			cpr3_err(ctrl, "unable to configure LDO state, rc=%d\n",

				 rc);

			return rc;

		}



		rc = msm_apm_set_supply(ctrl->apm, new_volt >= apm_volt

				? ctrl->apm_high_supply : ctrl->apm_low_supply);

		if (rc) {
@@ -1020,7 +1122,8 @@ static int cpr3_regulator_scale_vdd_voltage(struct cpr3_controller *ctrl, 
		/* Decreasing VDD voltage */

		rc = cpr3_regulator_config_ldo(ctrl, aggr_corner->floor_volt,

					       last_max_volt, apm_crossing ?

					       apm_volt : last_volt);

					       apm_volt : last_volt, false,

					       new_volt);

		if (rc) {

			cpr3_err(ctrl, "unable to configure LDO state, rc=%d\n",

				 rc);
@@ -1056,7 +1159,8 @@ static int cpr3_regulator_scale_vdd_voltage(struct cpr3_controller *ctrl, 
	if (new_volt >= last_volt) {

		/* Increasing VDD voltage */

		rc = cpr3_regulator_config_ldo(ctrl, aggr_corner->floor_volt,

					       max_volt, new_volt);

					       max_volt, new_volt, false,

					       new_volt);

		if (rc) {

			cpr3_err(ctrl, "unable to configure LDO state, rc=%d\n",

				 rc);