interconnect: qcom: icc-rpmh: Add QoS configuration support

Add QoS support for QNOC device for configuring priority,
priority forward disable and urgency forwarding. QoS is required
to prioritize the traffic originating from different interconnect
masters at NoC (Network On Chip).

Signed-off-by: Odelu Kukatla <quic_okukatla@quicinc.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20240607173927.26321-2-quic_okukatla@quicinc.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>

drivers/interconnect/qcom/icc-rpmh.c

@@ -1,8 +1,11 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
  */
 
+#include <linux/bitfield.h>
+#include <linux/clk.h>
 #include <linux/interconnect.h>
 #include <linux/interconnect-provider.h>
 #include <linux/module.h>
@@ -14,6 +17,38 @@
 #include "icc-common.h"
 #include "icc-rpmh.h"
 
+/* QNOC QoS */
+#define QOSGEN_MAINCTL_LO(p, qp)	(0x8 + (p->port_offsets[qp]))
+#define QOS_SLV_URG_MSG_EN_MASK		GENMASK(3, 3)
+#define QOS_DFLT_PRIO_MASK		GENMASK(6, 4)
+#define QOS_DISABLE_MASK		GENMASK(24, 24)
+
+/**
+ * qcom_icc_set_qos - initialize static QoS configurations
+ * @qp: qcom icc provider to which @node belongs
+ * @node: qcom icc node to operate on
+ */
+static void qcom_icc_set_qos(struct qcom_icc_provider *qp,
+			     struct qcom_icc_node *node)
+{
+	const struct qcom_icc_qosbox *qos = node->qosbox;
+	int port;
+
+	for (port = 0; port < qos->num_ports; port++) {
+		regmap_update_bits(qp->regmap, QOSGEN_MAINCTL_LO(qos, port),
+				   QOS_DISABLE_MASK,
+				   FIELD_PREP(QOS_DISABLE_MASK, qos->prio_fwd_disable));
+
+		regmap_update_bits(qp->regmap, QOSGEN_MAINCTL_LO(qos, port),
+				   QOS_DFLT_PRIO_MASK,
+				   FIELD_PREP(QOS_DFLT_PRIO_MASK, qos->prio));
+
+		regmap_update_bits(qp->regmap, QOSGEN_MAINCTL_LO(qos, port),
+				   QOS_SLV_URG_MSG_EN_MASK,
+				   FIELD_PREP(QOS_SLV_URG_MSG_EN_MASK, qos->urg_fwd));
+	}
+}
+
 /**
  * qcom_icc_pre_aggregate - cleans up stale values from prior icc_set
  * @node: icc node to operate on
@@ -159,6 +194,36 @@ int qcom_icc_bcm_init(struct qcom_icc_bcm *bcm, struct device *dev)
 }
 EXPORT_SYMBOL_GPL(qcom_icc_bcm_init);
 
+/**
+ * qcom_icc_rpmh_configure_qos - configure QoS parameters
+ * @qp: qcom icc provider associated with QoS endpoint nodes
+ *
+ * Return: 0 on success, or an error code otherwise
+ */
+static int qcom_icc_rpmh_configure_qos(struct qcom_icc_provider *qp)
+{
+	struct qcom_icc_node *qnode;
+	size_t i;
+	int ret;
+
+	ret = clk_bulk_prepare_enable(qp->num_clks, qp->clks);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < qp->num_nodes; i++) {
+		qnode = qp->nodes[i];
+		if (!qnode)
+			continue;
+
+		if (qnode->qosbox)
+			qcom_icc_set_qos(qp, qnode);
+	}
+
+	clk_bulk_disable_unprepare(qp->num_clks, qp->clks);
+
+	return ret;
+}
+
 int qcom_icc_rpmh_probe(struct platform_device *pdev)
 {
 	const struct qcom_icc_desc *desc;
@@ -199,7 +264,9 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev)
 
 	qp->dev = dev;
 	qp->bcms = desc->bcms;
+	qp->nodes = desc->nodes;
 	qp->num_bcms = desc->num_bcms;
+	qp->num_nodes = desc->num_nodes;
 
 	qp->voter = of_bcm_voter_get(qp->dev, NULL);
 	if (IS_ERR(qp->voter))
@@ -229,6 +296,32 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev)
 		data->nodes[i] = node;
 	}
 
+	if (desc->config) {
+		struct resource *res;
+		void __iomem *base;
+
+		base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+		if (IS_ERR(base))
+			goto skip_qos_config;
+
+		qp->regmap = devm_regmap_init_mmio(dev, base, desc->config);
+		if (IS_ERR(qp->regmap)) {
+			dev_info(dev, "Skipping QoS, regmap failed; %ld\n", PTR_ERR(qp->regmap));
+			goto skip_qos_config;
+		}
+
+		qp->num_clks = devm_clk_bulk_get_all(qp->dev, &qp->clks);
+		if (qp->num_clks < 0) {
+			dev_info(dev, "Skipping QoS, failed to get clk: %d\n", qp->num_clks);
+			goto skip_qos_config;
+		}
+
+		ret = qcom_icc_rpmh_configure_qos(qp);
+		if (ret)
+			dev_info(dev, "Failed to program QoS: %d\n", ret);
+	}
+
+skip_qos_config:
 	ret = icc_provider_register(provider);
 	if (ret)
 		goto err_remove_nodes;

drivers/interconnect/qcom/icc-rpmh.h

@@ -1,12 +1,14 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
  */
 
 #ifndef __DRIVERS_INTERCONNECT_QCOM_ICC_RPMH_H__
 #define __DRIVERS_INTERCONNECT_QCOM_ICC_RPMH_H__
 
 #include <dt-bindings/interconnect/qcom,icc.h>
+#include <linux/regmap.h>
 
 #define to_qcom_provider(_provider) \
 	container_of(_provider, struct qcom_icc_provider, provider)
@@ -18,6 +20,11 @@
  * @bcms: list of bcms that maps to the provider
  * @num_bcms: number of @bcms
  * @voter: bcm voter targeted by this provider
+ * @nodes: list of icc nodes that maps to the provider
+ * @num_nodes: number of @nodes
+ * @regmap: used for QoS, register access
+ * @clks : clks required for register access
+ * @num_clks: number of @clks
  */
 struct qcom_icc_provider {
 	struct icc_provider provider;
@@ -25,6 +32,11 @@ struct qcom_icc_provider {
 	struct qcom_icc_bcm * const *bcms;
 	size_t num_bcms;
 	struct bcm_voter *voter;
+	struct qcom_icc_node * const *nodes;
+	size_t num_nodes;
+	struct regmap *regmap;
+	struct clk_bulk_data *clks;
+	int num_clks;
 };
 
 /**
@@ -41,6 +53,26 @@ struct bcm_db {
 	u8 reserved;
 };
 
+#define MAX_PORTS		2
+
+/**
+ * struct qcom_icc_qosbox - Qualcomm specific QoS config
+ * @prio: priority value assigned to requests on the node
+ * @urg_fwd: whether to forward the urgency promotion issued by master
+ * (endpoint), or discard
+ * @prio_fwd_disable: whether to forward the priority driven by master, or
+ * override by @prio
+ * @num_ports: number of @ports
+ * @port_offsets: qos register offsets
+ */
+struct qcom_icc_qosbox {
+	const u32 prio;
+	const bool urg_fwd;
+	const bool prio_fwd_disable;
+	const u32 num_ports;
+	const u32 port_offsets[MAX_PORTS];
+};
+
 #define MAX_LINKS		128
 #define MAX_BCMS		64
 #define MAX_BCM_PER_NODE	3
@@ -58,6 +90,7 @@ struct bcm_db {
  * @max_peak: current max aggregate value of all peak bw requests
  * @bcms: list of bcms associated with this logical node
  * @num_bcms: num of @bcms
+ * @qosbox: QoS config data associated with node
  */
 struct qcom_icc_node {
 	const char *name;
@@ -70,6 +103,7 @@ struct qcom_icc_node {
 	u64 max_peak[QCOM_ICC_NUM_BUCKETS];
 	struct qcom_icc_bcm *bcms[MAX_BCM_PER_NODE];
 	size_t num_bcms;
+	const struct qcom_icc_qosbox *qosbox;
 };
 
 /**
@@ -114,6 +148,7 @@ struct qcom_icc_fabric {
 };
 
 struct qcom_icc_desc {
+	const struct regmap_config *config;
 	struct qcom_icc_node * const *nodes;
 	size_t num_nodes;
 	struct qcom_icc_bcm * const *bcms;