[PATCH v6 09/12] firmware: arm_scmi: add Powercap MAI get/set support

Add support for Power Measurement Averaging Interval (MAI) get and set
operations to the SCMI powercap protocol driver. Extends scmi_powercap_info
to store MAI configuration and implement MAI get/set via xfer and optional
fast-channel support.

Signed-off-by: Philip Radford <[email protected]>
---
V5->V6
- Fixed comment length
- Changed warning message wording
- Fixed line lengths and alignment
- Updated docs for new fields
---
 drivers/firmware/arm_scmi/powercap.c | 127 +++++++++++++++++++++++++++
 include/linux/scmi_protocol.h        |  18 ++++
 2 files changed, 145 insertions(+)

diff --git a/drivers/firmware/arm_scmi/powercap.c b/drivers/firmware/arm_scmi/powercap.c
index 09152bb8642c..dfec09fd687f 100644
--- a/drivers/firmware/arm_scmi/powercap.c
+++ b/drivers/firmware/arm_scmi/powercap.c
@@ -403,6 +403,34 @@ scmi_powercap_domain_attrs_process(const struct scmi_protocol_handle *ph,
 		dom_info->notify_powercap_measurement_change =
 			SUPPORTS_POWERCAP_MEASUREMENTS_CHANGE_NOTIFY(flags);
 
+	if (PROTOCOL_REV_MAJOR(ph->version) >= 0x3) {
+		struct scmi_msg_resp_powercap_domain_attributes_v3 *resp_v3 = r;
+
+		flags = le32_to_cpu(resp_v3->attributes);
+		if (pinfo->notify_measurements_cmd)
+			dom_info->notify_powercap_measurement_change =
+			       SUPPORTS_POWERCAP_MEASUREMENTS_CHANGE_NOTIFY(flags);
+
+		dom_info->mai_config = SUPPORTS_POWERCAP_MAI_CONFIGURATION(flags);
+		dom_info->min_mai = le32_to_cpu(resp_v3->min_mai);
+		dom_info->max_mai = le32_to_cpu(resp_v3->max_mai);
+		dom_info->mai_step = le32_to_cpu(resp_v3->mai_step);
+
+		if (dom_info->mai_config) {
+			ret = scmi_powercap_validate(dom_info->min_mai,
+						     dom_info->max_mai,
+						     dom_info->mai_step,
+						     dom_info->mai_config);
+
+			if (ret) {
+				dev_warn(ph->dev, "Platform reported invalid MAI config for domain %d - %s\n",
+					 dom_info->id, dom_info->name);
+
+				return ret;
+			}
+		}
+	}
+
 	dom_info->extended_names = SUPPORTS_EXTENDED_NAMES(flags);
 
 	dom_info->async_powercap_cap_set =
@@ -1084,6 +1112,103 @@ static int scmi_powercap_cap_enable_get(const struct scmi_protocol_handle *ph,
 	return 0;
 }
 
+static int scmi_powercap_xfer_mai_get(const struct scmi_protocol_handle *ph,
+				      u32 domain_id, u32 *mai)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = ph->xops->xfer_get_init(ph, POWERCAP_MAI_GET, sizeof(u32),
+				      sizeof(u32), &t);
+
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(domain_id, t->tx.buf);
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret)
+		*mai = get_unaligned_le32(t->rx.buf);
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int scmi_powercap_xfer_mai_set(const struct scmi_protocol_handle *ph,
+				      u32 domain_id, u32 mai)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_powercap_cap_or_pai_set *msg;
+
+	ret = ph->xops->xfer_get_init(ph, POWERCAP_MAI_SET, sizeof(*msg),
+				      0, &t);
+	if (ret)
+		return ret;
+
+	msg = t->tx.buf;
+	msg->domain_id = cpu_to_le32(domain_id);
+	msg->flags = cpu_to_le32(0);
+	msg->value = cpu_to_le32(mai);
+
+	ret = ph->xops->do_xfer(ph, t);
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int
+scmi_powercap_measurements_interval_get(const struct scmi_protocol_handle *ph,
+					u32 domain_id,
+					u32 *val)
+{
+	const struct scmi_powercap_info *pc;
+	struct scmi_fc_info *fci;
+
+	if (!val)
+		return -EINVAL;
+
+	pc = scmi_powercap_dom_info_get(ph, domain_id);
+	if (!pc)
+		return -EINVAL;
+
+	fci = pc->cpli[CPL0].fc_info;
+	if (fci && fci[POWERCAP_FC_MAI].get_addr) {
+		*val = ioread32(fci[POWERCAP_FC_MAI].get_addr);
+		trace_scmi_fc_call(SCMI_PROTOCOL_POWERCAP, POWERCAP_MAI_GET,
+				   domain_id, 0, *val, 0);
+		return 0;
+	}
+
+	return scmi_powercap_xfer_mai_get(ph, domain_id, val);
+}
+
+static int
+scmi_powercap_measurements_interval_set(const struct scmi_protocol_handle *ph,
+					u32 domain_id,
+					u32 val)
+{
+	const struct scmi_powercap_info *pc;
+	struct scmi_fc_info *fci;
+
+	pc = scmi_powercap_dom_info_get(ph, domain_id);
+	if (!pc)
+		return -EINVAL;
+
+	if (!pc->mai_config || !val || val < pc->min_mai || val > pc->max_mai)
+		return -EINVAL;
+
+	fci = pc->cpli[CPL0].fc_info;
+	if (fci && fci[POWERCAP_FC_MAI].set_addr) {
+		iowrite32(val, fci[POWERCAP_FC_MAI].set_addr);
+		ph->hops->fastchannel_db_ring(fci[POWERCAP_FC_MAI].set_db);
+		trace_scmi_fc_call(SCMI_PROTOCOL_POWERCAP, POWERCAP_MAI_SET, domain_id, 0, val, 0);
+		return 0;
+	}
+
+	return scmi_powercap_xfer_mai_set(ph, domain_id, val);
+}
+
 static const struct scmi_powercap_proto_ops powercap_proto_ops = {
 	.num_domains_get = scmi_powercap_num_domains_get,
 	.info_get = scmi_powercap_dom_info_get,
@@ -1096,6 +1221,8 @@ static const struct scmi_powercap_proto_ops powercap_proto_ops = {
 	.measurements_get = scmi_powercap_measurements_get,
 	.measurements_threshold_set = scmi_powercap_measurements_threshold_set,
 	.measurements_threshold_get = scmi_powercap_measurements_threshold_get,
+	.measurements_interval_get = scmi_powercap_measurements_interval_get,
+	.measurements_interval_set = scmi_powercap_measurements_interval_set,
 };
 
 static void scmi_powercap_domain_init_fc(const struct scmi_protocol_handle *ph,
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index d0f6c0102559..90615611be4a 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -654,6 +654,12 @@ struct scmi_powercap_cpl_info {
  *		       reports power data on an abstract linear scale.
  * @extended_names: Support for long names.
  * @fastchannels: Support for at least one fastchannel,
+ * @mai_config: MAI configuration support.
+ * @min_mai: Minimum supported Power Measurement Averaging Interval in
+ *			microseconds.
+ * @max_mai: Maximum supporte Power Measurement Averaging Interval in
+			microseconds.
+ * @mai_step: Step size between supported MAI values in microseconds.
  * @name: name assigned to the Powercap Domain by platform.
  * @sustainable_power: Maximum sustainable power consumption for this domain
  *		       under normal conditions.
@@ -675,6 +681,10 @@ struct scmi_powercap_info {
 	bool powercap_scale_uw;
 	bool extended_names;
 	bool fastchannels;
+	bool mai_config;
+	u32 min_mai;
+	u32 max_mai;
+	u32 mai_step;
 	char name[SCMI_MAX_STR_SIZE];
 	unsigned int sustainable_power;
 	unsigned int accuracy;
@@ -733,6 +743,10 @@ struct scmi_powercap_info {
  * @measurements_threshold_get: get the currently configured low and high power
  *				thresholds used when registering callbacks for
  *				notification POWERCAP_MEASUREMENTS_NOTIFY.
+ * @measurements_interval_get: get the current Power Measurement Averaging
+ *				Interval (MAI) value for the specified domain.
+ * @measurements_interval_set: set the Power Measurement Averaging Interval
+ *				(MAI) value for the specified domain.
  */
 struct scmi_powercap_proto_ops {
 	int (*num_domains_get)(const struct scmi_protocol_handle *ph);
@@ -758,6 +772,10 @@ struct scmi_powercap_proto_ops {
 	int (*measurements_threshold_get)(const struct scmi_protocol_handle *ph,
 					  u32 domain_id, u32 *power_thresh_low,
 					  u32 *power_thresh_high);
+	int (*measurements_interval_get)(const struct scmi_protocol_handle *ph,
+					 u32 domain_id, u32 *val);
+	int (*measurements_interval_set)(const struct scmi_protocol_handle *ph,
+					 u32 domain_id, u32 val);
 };
 
 enum scmi_pinctrl_selector_type {
-- 
2.47.3