regulator: cpr4: Add miscellaneous fuse based voltage adjustments

Apply voltage adjustments for required voltage corners based on
different values of selected miscellaneous fuse bits. Apply the
adjustments to both open-loop voltages and closed-loop target
quotients.

CRs-Fixed: 982984
Change-Id: Ic45949afc8445d35c245434a7f51e4859a5978ad
Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>

Documentation/devicetree/bindings/regulator/cpr4-apss-regulator.txt

@@ -348,6 +348,27 @@ APSS specific properties:
 		    regardless of the fuse combination and speed bin found
 		    on a given chip.
 
+- qcom,cpr-misc-fuse-voltage-adjustment
+	Usage:      optional
+	Value type: <prop-encoded-array>
+	Definition: A grouping of integer tuple lists where each tuple defines
+		    the voltage adjustments in microvolts for each voltage
+		    corner in order from lowest to highest. This adjustment is
+		    applied to both open-loop and closed-loop voltages.
+
+		    Each tuple list must contain a number of tuples equal to
+		    2 to the power of the number of bits selected for misc
+		    voltage adj fuse definition. For MSMTITANIUM the tuple
+		    list must contain 2 tuples for the 1-bit misc fuse.
+		    Tuples in a list should be specified in ascending order
+		    according to the misc fuse value assuming that the fuse
+		    is treated like an unsigned integer.
+
+		    The tuple list grouping must contain qcom,cpr-speed-bins
+		    number of tuple lists in which case the lists are matched to
+		    speed bins 1-to-1 or exactly 1 list which is used regardless
+		    of the speed bin found on a given chip.
+
 =======
 Example
 =======
@@ -422,6 +443,13 @@ apc_cpr: cpr4-ctrl@b018000 {
 				1689600000 1843200000 1958400000
 				2150400000 2208000000>;
 
+			qcom,cpr-misc-fuse-voltage-adjustment =
+				/* Speed bin 0; misc fuse 0..1 */
+				<    0     0     0     0
+				     0     0     0     0>,
+				<    0     0 30000     0
+				     0     0     0     0>;
+
 			qcom,allow-voltage-interpolation;
 			qcom,allow-quotient-interpolation;
 			qcom,cpr-scaled-open-loop-voltage-as-ceiling;

drivers/regulator/cpr4-apss-regulator.c

@@ -66,6 +66,7 @@ struct cpr4_msmtitanium_apss_fuses {
 	u64	cpr_fusing_rev;
 	u64	boost_cfg;
 	u64	boost_voltage;
+	u64	misc;
 };
 
 /*
@@ -155,6 +156,17 @@ static const struct cpr3_fuse_param msmtitanium_apss_boost_fuse_volt_param[] = {
 	{},
 };
 
+static const struct cpr3_fuse_param msmtitanium_misc_fuse_volt_adj_param[] = {
+	{36, 54, 54},
+	{},
+};
+
+/*
+ * The number of possible values for misc fuse is
+ * 2^(#bits defined for misc fuse)
+ */
+#define MSMTITANIUM_MISC_FUSE_VAL_COUNT		BIT(1)
+
 /*
  * Open loop voltage fuse reference voltages in microvolts for MSMTITANIUM
  */
@@ -231,6 +243,20 @@ static int cpr4_msmtitanium_apss_read_fuse_data(struct cpr3_regulator *vreg)
 	}
 	cpr3_info(vreg, "CPR fusing revision = %llu\n", fuse->cpr_fusing_rev);
 
+	rc = cpr3_read_fuse_param(base, msmtitanium_misc_fuse_volt_adj_param,
+				&fuse->misc);
+	if (rc) {
+		cpr3_err(vreg, "Unable to read misc voltage adjustment fuse, rc=%d\n",
+			rc);
+		return rc;
+	}
+	cpr3_info(vreg, "CPR misc fuse value = %llu\n", fuse->misc);
+	if (fuse->misc >= MSMTITANIUM_MISC_FUSE_VAL_COUNT) {
+		cpr3_err(vreg, "CPR misc fuse value = %llu, should be < %lu\n",
+			fuse->misc, MSMTITANIUM_MISC_FUSE_VAL_COUNT);
+		return -EINVAL;
+	}
+
 	for (i = 0; i < MSMTITANIUM_APSS_FUSE_CORNERS; i++) {
 		rc = cpr3_read_fuse_param(base,
 				msmtitanium_apss_init_voltage_param[i],
@@ -324,6 +350,78 @@ static int cpr4_apss_parse_corner_data(struct cpr3_regulator *vreg)
 	return rc;
 }
 
+/**
+ * cpr4_apss_parse_misc_fuse_voltage_adjustments() - fill an array from a
+ *		portion of the voltage adjustments specified based on
+ *		miscellaneous fuse bits.
+ * @vreg:		Pointer to the CPR3 regulator
+ * @volt_adjust:	Voltage adjustment output data array which must be
+ *			of size vreg->corner_count
+ *
+ * cpr3_parse_common_corner_data() must be called for vreg before this function
+ * is called so that speed bin size elements are initialized.
+ *
+ * Two formats are supported for the device tree property:
+ * 1. Length == tuple_list_size * vreg->corner_count
+ *	(reading begins at index 0)
+ * 2. Length == tuple_list_size * vreg->speed_bin_corner_sum
+ *	(reading begins at index tuple_list_size * vreg->speed_bin_offset)
+ *
+ * Here, tuple_list_size is the number of possible values for misc fuse.
+ * All other property lengths are treated as errors.
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_apss_parse_misc_fuse_voltage_adjustments(
+	struct cpr3_regulator *vreg, u32 *volt_adjust)
+{
+	struct device_node *node = vreg->of_node;
+	struct cpr4_msmtitanium_apss_fuses *fuse = vreg->platform_fuses;
+	int tuple_list_size = MSMTITANIUM_MISC_FUSE_VAL_COUNT;
+	int i, offset, rc, len = 0;
+	const char *prop_name = "qcom,cpr-misc-fuse-voltage-adjustment";
+
+	if (!of_find_property(node, prop_name, &len)) {
+		cpr3_err(vreg, "property %s is missing\n", prop_name);
+		return -EINVAL;
+	}
+
+	if (len == tuple_list_size * vreg->corner_count * sizeof(u32)) {
+		offset = 0;
+	} else if (vreg->speed_bin_corner_sum > 0 &&
+			len == tuple_list_size * vreg->speed_bin_corner_sum
+			* sizeof(u32)) {
+		offset = tuple_list_size * vreg->speed_bin_offset
+			+ fuse->misc * vreg->corner_count;
+	} else {
+		if (vreg->speed_bin_corner_sum > 0)
+			cpr3_err(vreg, "property %s has invalid length=%d, should be %zu or %zu\n",
+				prop_name, len,
+				tuple_list_size * vreg->corner_count
+					* sizeof(u32),
+				tuple_list_size * vreg->speed_bin_corner_sum
+					* sizeof(u32));
+		else
+			cpr3_err(vreg, "property %s has invalid length=%d, should be %zu\n",
+				prop_name, len,
+				tuple_list_size * vreg->corner_count
+				* sizeof(u32));
+		return -EINVAL;
+	}
+
+	for (i = 0; i < vreg->corner_count; i++) {
+		rc = of_property_read_u32_index(node, prop_name, offset + i,
+						&volt_adjust[i]);
+		if (rc) {
+			cpr3_err(vreg, "error reading property %s, rc=%d\n",
+				prop_name, rc);
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
 /**
  * cpr4_msmtitanium_apss_calculate_open_loop_voltages() - calculate the open-loop
  *		voltage for each corner of a CPR3 regulator
@@ -349,7 +447,7 @@ static int cpr4_msmtitanium_apss_calculate_open_loop_voltages(
 	int i, j, rc = 0;
 	bool allow_interpolation;
 	u64 freq_low, volt_low, freq_high, volt_high;
-	int *fuse_volt;
+	int *fuse_volt, *misc_adj_volt;
 	int *fmax_corner;
 
 	fuse_volt = kcalloc(vreg->fuse_corner_count, sizeof(*fuse_volt),
@@ -445,8 +543,34 @@ done:
 		if (rc)
 			cpr3_err(vreg, "open-loop voltage adjustment failed, rc=%d\n",
 				rc);
+
+		if (of_find_property(node,
+			"qcom,cpr-misc-fuse-voltage-adjustment",
+			NULL)) {
+			misc_adj_volt = kcalloc(vreg->corner_count,
+					sizeof(*misc_adj_volt), GFP_KERNEL);
+			if (!misc_adj_volt) {
+				rc = -ENOMEM;
+				goto _exit;
+			}
+
+			rc = cpr4_apss_parse_misc_fuse_voltage_adjustments(vreg,
+				misc_adj_volt);
+			if (rc) {
+				cpr3_err(vreg, "qcom,cpr-misc-fuse-voltage-adjustment reading failed, rc=%d\n",
+					rc);
+				kfree(misc_adj_volt);
+				goto _exit;
+			}
+
+			for (i = 0; i < vreg->corner_count; i++)
+				vreg->corner[i].open_loop_volt
+						+= misc_adj_volt[i];
+			kfree(misc_adj_volt);
+		}
 	}
 
+_exit:
 	kfree(fuse_volt);
 	kfree(fmax_corner);
 	return rc;
@@ -525,6 +649,7 @@ static int cpr4_msmtitanium_apss_calculate_target_quotients(
 	int i, j, fuse_corner, quot_adjust;
 	int *fmax_corner;
 	int *volt_adjust, *volt_adjust_fuse, *ro_scale;
+	int *voltage_adj_misc;
 
 	/* Log fused quotient values for debugging purposes. */
 	cpr3_info(vreg, "fused   LowSVS: quot[%2llu]=%4llu\n",
@@ -567,6 +692,30 @@ static int cpr4_msmtitanium_apss_calculate_target_quotients(
 		goto done;
 	}
 
+	if (of_find_property(vreg->of_node,
+		"qcom,cpr-misc-fuse-voltage-adjustment", NULL)) {
+		voltage_adj_misc = kcalloc(vreg->corner_count,
+				sizeof(*voltage_adj_misc), GFP_KERNEL);
+		if (!voltage_adj_misc) {
+			rc = -ENOMEM;
+			goto done;
+		}
+
+		rc = cpr4_apss_parse_misc_fuse_voltage_adjustments(vreg,
+			voltage_adj_misc);
+		if (rc) {
+			cpr3_err(vreg, "qcom,cpr-misc-fuse-voltage-adjustment reading failed, rc=%d\n",
+				rc);
+			kfree(voltage_adj_misc);
+			goto done;
+		}
+
+		for (i = 0; i < vreg->corner_count; i++)
+			volt_adjust[i] += voltage_adj_misc[i];
+
+		kfree(voltage_adj_misc);
+	}
+
 	if (!allow_interpolation) {
 		/* Use fused target quotients for lower frequencies. */
 		return cpr4_msmtitanium_apss_set_no_interpolation_quotients(