[RFC V3 3/4] soc: qcom: Introduce SCMI based Memlat (Memory Latency) governor

Sibi Sankar quic_sibis at quicinc.com
Tue Jul 2 12:14:39 PDT 2024


Introduce a client driver that uses the memlat algorithm string hosted
on ARM SCMI QCOM Vendor Protocol to detect memory latency workloads and
control frequency/level of the various memory buses (DDR/LLCC/DDR_QOS).

Co-developed-by: Shivnandan Kumar <quic_kshivnan at quicinc.com>
Signed-off-by: Shivnandan Kumar <quic_kshivnan at quicinc.com>
Co-developed-by: Ramakrishna Gottimukkula <quic_rgottimu at quicinc.com>
Signed-off-by: Ramakrishna Gottimukkula <quic_rgottimu at quicinc.com>
Co-developed-by: Amir Vajid <avajid at quicinc.com>
Signed-off-by: Amir Vajid <avajid at quicinc.com>
Signed-off-by: Sibi Sankar <quic_sibis at quicinc.com>
---

V2:
* Make driver changes to the accommodate bindings changes. [Rob]
* Replace explicit of_node_put with _free.

 drivers/soc/qcom/Kconfig            |  12 +
 drivers/soc/qcom/Makefile           |   1 +
 drivers/soc/qcom/qcom_scmi_client.c | 583 ++++++++++++++++++++++++++++
 3 files changed, 596 insertions(+)
 create mode 100644 drivers/soc/qcom/qcom_scmi_client.c

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index 432c85bd8ad4..b253504bd386 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -294,4 +294,16 @@ config QCOM_PBS
 	  This module provides the APIs to the client drivers that wants to send the
 	  PBS trigger event to the PBS RAM.
 
+config QCOM_SCMI_CLIENT
+	tristate "Qualcomm Technologies Inc. SCMI client driver"
+	depends on ARM_SCMI_PROTOCOL_VENDOR_QCOM || COMPILE_TEST
+	default n
+	help
+	  This driver uses the memlat algorithm string hosted on QCOM SCMI
+	  Vendor Protocol to detect memory latency workloads and control
+	  frequency/level of the various memory buses (DDR/LLCC/DDR_QOS).
+
+	  This driver defines/documents the parameter IDs used while configuring
+	  the memory buses.
+
 endmenu
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index d3560f861085..8a2e832d1d5d 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_QCOM_APR) += apr.o
 obj-$(CONFIG_QCOM_LLCC) += llcc-qcom.o
 obj-$(CONFIG_QCOM_KRYO_L2_ACCESSORS) +=	kryo-l2-accessors.o
 obj-$(CONFIG_QCOM_ICC_BWMON)	+= icc-bwmon.o
+obj-$(CONFIG_QCOM_SCMI_CLIENT)	+= qcom_scmi_client.o
 qcom_ice-objs			+= ice.o
 obj-$(CONFIG_QCOM_INLINE_CRYPTO_ENGINE)	+= qcom_ice.o
 obj-$(CONFIG_QCOM_PBS) +=	qcom-pbs.o
diff --git a/drivers/soc/qcom/qcom_scmi_client.c b/drivers/soc/qcom/qcom_scmi_client.c
new file mode 100644
index 000000000000..8369b415c0ab
--- /dev/null
+++ b/drivers/soc/qcom/qcom_scmi_client.c
@@ -0,0 +1,583 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/cpu.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/qcom_scmi_vendor.h>
+#include <linux/scmi_protocol.h>
+#include <linux/units.h>
+#include <dt-bindings/soc/qcom,scmi-vendor.h>
+
+#define MEMLAT_ALGO_STR				0x4D454D4C4154 /* MEMLAT */
+#define INVALID_IDX				0xff
+#define MAX_MEMORY_TYPES			3
+#define MAX_MONITOR_CNT				4
+#define MAX_NAME_LEN				20
+#define MAX_MAP_ENTRIES				7
+#define CPUCP_DEFAULT_SAMPLING_PERIOD_MS	4
+#define CPUCP_DEFAULT_FREQ_METHOD		1
+
+/**
+ * scmi_memlat_protocol_cmd - parameter_ids supported by the "MEMLAT" algo_str hosted
+ *                            by the Qualcomm SCMI Vendor Protocol on the SCMI controller.
+ *
+ * MEMLAT (Memory Latency) monitors the counters to detect memory latency bound workloads
+ * and scales the frequency/levels of the memory buses accordingly.
+ *
+ * @MEMLAT_SET_MEM_GROUP: initializes the frequency/level scaling functions for the memory bus.
+ * @MEMLAT_SET_MONITOR: configures the monitor to work on a specific memory bus.
+ * @MEMLAT_SET_COMMON_EV_MAP: set up common counters used to monitor the cpu frequency.
+ * @MEMLAT_SET_GRP_EV_MAP: set up any specific counters used to monitor the memory bus.
+ * @MEMLAT_IPM_CEIL: set the IPM (Instruction Per Misses) ceiling per monitor.
+ * @MEMLAT_SAMPLE_MS: set the sampling period for all the monitors.
+ * MEMLAT_MON_FREQ_MAP: setup the cpufreq to memfreq map.
+ * MEMLAT_SET_MIN_FREQ: set the max frequency of the memory bus.
+ * MEMLAT_SET_MAX_FREQ: set the min frequency of the memory bus.
+ * MEMLAT_START_TIMER: start all the monitors with the requested sampling period.
+ * MEMLAT_START_TIMER: stop all the running monitors.
+ * MEMLAT_SET_EFFECTIVE_FREQ_METHOD: set the method used to determine cpu frequency.
+ */
+enum scmi_memlat_protocol_cmd {
+	MEMLAT_SET_MEM_GROUP = 16,
+	MEMLAT_SET_MONITOR,
+	MEMLAT_SET_COMMON_EV_MAP,
+	MEMLAT_SET_GRP_EV_MAP,
+	MEMLAT_IPM_CEIL = 23,
+	MEMLAT_SAMPLE_MS = 31,
+	MEMLAT_MON_FREQ_MAP,
+	MEMLAT_SET_MIN_FREQ,
+	MEMLAT_SET_MAX_FREQ,
+	MEMLAT_START_TIMER = 36,
+	MEMLAT_STOP_TIMER,
+	MEMLAT_SET_EFFECTIVE_FREQ_METHOD = 39,
+};
+
+struct map_table {
+	u16 v1;
+	u16 v2;
+};
+
+struct map_param_msg {
+	u32 hw_type;
+	u32 mon_idx;
+	u32 nr_rows;
+	struct map_table tbl[MAX_MAP_ENTRIES];
+} __packed;
+
+struct node_msg {
+	u32 cpumask;
+	u32 hw_type;
+	u32 mon_type;
+	u32 mon_idx;
+	char mon_name[MAX_NAME_LEN];
+};
+
+struct scalar_param_msg {
+	u32 hw_type;
+	u32 mon_idx;
+	u32 val;
+};
+
+enum common_ev_idx {
+	INST_IDX,
+	CYC_IDX,
+	CONST_CYC_IDX,
+	FE_STALL_IDX,
+	BE_STALL_IDX,
+	NUM_COMMON_EVS
+};
+
+enum grp_ev_idx {
+	MISS_IDX,
+	WB_IDX,
+	ACC_IDX,
+	NUM_GRP_EVS
+};
+
+#define EV_CPU_CYCLES		0
+#define EV_INST_RETIRED		2
+#define EV_L2_D_RFILL		5
+
+struct ev_map_msg {
+	u32 num_evs;
+	u32 hw_type;
+	u32 cid[NUM_COMMON_EVS];
+};
+
+struct cpufreq_memfreq_map {
+	unsigned int cpufreq_mhz;
+	unsigned int memfreq_khz;
+};
+
+struct scmi_monitor_info {
+	struct cpufreq_memfreq_map *freq_map;
+	char mon_name[MAX_NAME_LEN];
+	u32 mon_idx;
+	u32 mon_type;
+	u32 ipm_ceil;
+	u32 mask;
+	u32 freq_map_len;
+};
+
+struct scmi_memory_info {
+	struct scmi_monitor_info *monitor[MAX_MONITOR_CNT];
+	u32 hw_type;
+	int monitor_cnt;
+	u32 min_freq;
+	u32 max_freq;
+};
+
+struct scmi_memlat_info {
+	struct scmi_protocol_handle *ph;
+	const struct qcom_scmi_vendor_ops *ops;
+	struct scmi_memory_info *memory[MAX_MEMORY_TYPES];
+	u32 cluster_info[NR_CPUS];
+	int memory_cnt;
+};
+
+static int populate_cluster_info(u32 *cluster_info)
+{
+	char name[MAX_NAME_LEN];
+	int i = 0;
+
+	struct device_node *cn __free(device_node) = of_find_node_by_path("/cpus");
+	if (!cn)
+		return -ENODEV;
+
+	struct device_node *map __free(device_node) = of_get_child_by_name(cn, "cpu-map");
+	if (!map)
+		return -ENODEV;
+
+	do {
+		snprintf(name, sizeof(name), "cluster%d", i);
+		struct device_node *c __free(device_node) = of_get_child_by_name(map, name);
+		if (!c)
+			break;
+
+		*(cluster_info + i) = of_get_child_count(c);
+		i++;
+	} while (1);
+
+	return 0;
+}
+
+static int populate_physical_mask(struct device_node *np, u32 *mask, u32 *cluster_info)
+{
+	struct device_node *dev_phandle;
+	int cpu, i = 0, physical_id;
+
+	do {
+		dev_phandle = of_parse_phandle(np, "cpus", i++);
+		cpu = of_cpu_node_to_id(dev_phandle);
+		if (cpu != -ENODEV) {
+			physical_id = topology_core_id(cpu);
+			for (int j = 0; j < topology_cluster_id(cpu); j++)
+				physical_id += *(cluster_info + j);
+			*mask |= BIT(physical_id);
+		}
+	} while (dev_phandle);
+
+	return 0;
+}
+
+static struct cpufreq_memfreq_map *init_cpufreq_memfreq_map(struct device *dev,
+							    struct scmi_memory_info *memory,
+							    struct device_node *of_node,
+							    u32 *cnt)
+{
+	struct device_node *tbl_np, *opp_np;
+	struct cpufreq_memfreq_map *tbl;
+	int ret, i = 0;
+	u32 level, len;
+	u64 rate;
+
+	tbl_np = of_parse_phandle(of_node, "operating-points-v2", 0);
+	if (!tbl_np)
+		return ERR_PTR(-ENODEV);
+
+	len = min(of_get_available_child_count(tbl_np), MAX_MAP_ENTRIES);
+	if (len == 0)
+		return ERR_PTR(-ENODEV);
+
+	tbl = devm_kzalloc(dev, (len + 1) * sizeof(struct cpufreq_memfreq_map),
+			   GFP_KERNEL);
+	if (!tbl)
+		return ERR_PTR(-ENOMEM);
+
+	for_each_available_child_of_node(tbl_np, opp_np) {
+		ret = of_property_read_u64_index(opp_np, "opp-hz", 0, &rate);
+		if (ret < 0)
+			return ERR_PTR(ret);
+
+		tbl[i].cpufreq_mhz = rate / HZ_PER_MHZ;
+
+		if (memory->hw_type != QCOM_MEM_TYPE_DDR_QOS) {
+			ret = of_property_read_u64_index(opp_np, "opp-hz", 1, &rate);
+			if (ret < 0)
+				return ERR_PTR(ret);
+
+			tbl[i].memfreq_khz = rate / HZ_PER_KHZ;
+		} else {
+			ret = of_property_read_u32(opp_np, "opp-level", &level);
+			if (ret < 0)
+				return ERR_PTR(ret);
+
+			tbl[i].memfreq_khz = level;
+		}
+
+		dev_dbg(dev, "Entry%d CPU:%u, Mem:%u\n", i, tbl[i].cpufreq_mhz, tbl[i].memfreq_khz);
+		i++;
+	}
+	*cnt = len;
+	tbl[i].cpufreq_mhz = 0;
+
+	return tbl;
+}
+
+static int process_scmi_memlat_of_node(struct scmi_device *sdev, struct scmi_memlat_info *info)
+{
+	struct scmi_monitor_info *monitor;
+	struct scmi_memory_info *memory;
+	char name[MAX_NAME_LEN];
+	u64 memfreq[2];
+	int ret;
+
+	ret = populate_cluster_info(info->cluster_info);
+	if (ret < 0) {
+		dev_err_probe(&sdev->dev, ret, "failed to populate cluster info\n");
+		goto err;
+	}
+
+	of_node_get(sdev->handle->dev->of_node);
+	do {
+		snprintf(name, sizeof(name), "memory-%d", info->memory_cnt);
+		struct device_node *memory_np __free(device_node) =
+			of_find_node_by_name(sdev->handle->dev->of_node, name);
+
+		if (!memory_np)
+			break;
+
+		memory = devm_kzalloc(&sdev->dev, sizeof(*memory), GFP_KERNEL);
+		if (!memory) {
+			ret = -ENOMEM;
+			goto err;
+		}
+
+		ret = of_property_read_u32(memory_np, "qcom,memory-type", &memory->hw_type);
+		if (ret) {
+			dev_err_probe(&sdev->dev, ret, "failed to read memory type\n");
+			goto err;
+		}
+
+		ret = of_property_read_u64_array(memory_np, "freq-table-hz", memfreq, 2);
+		if (ret && (ret != -EINVAL)) {
+			dev_err_probe(&sdev->dev, ret, "failed to read min/max freq\n");
+			goto err;
+		}
+
+		if (memory->hw_type != QCOM_MEM_TYPE_DDR_QOS) {
+			memory->min_freq = memfreq[0] / HZ_PER_KHZ;
+			memory->max_freq = memfreq[1] / HZ_PER_KHZ;
+		} else {
+			memory->min_freq = memfreq[0];
+			memory->max_freq = memfreq[1];
+		}
+		info->memory[info->memory_cnt++] = memory;
+
+		do {
+			snprintf(name, sizeof(name), "monitor-%d", memory->monitor_cnt);
+			struct device_node *monitor_np __free(device_node) =
+				of_get_child_by_name(memory_np, name);
+
+			if (!monitor_np)
+				break;
+
+			monitor = devm_kzalloc(&sdev->dev, sizeof(*monitor), GFP_KERNEL);
+			if (!monitor) {
+				ret = -ENOMEM;
+				goto err;
+			}
+
+			monitor->mon_type = of_property_read_bool(monitor_np, "qcom,compute-type");
+			if (!monitor->mon_type) {
+				ret = of_property_read_u32(monitor_np, "qcom,ipm-ceil",
+							   &monitor->ipm_ceil);
+				if (ret) {
+					dev_err_probe(&sdev->dev, ret,
+						      "failed to read IPM ceiling\n");
+					goto err;
+				}
+			}
+
+			/*
+			 * Variants of the SoC having reduced number of cpus operate
+			 * with the same number of logical cpus but the physical
+			 * cpu disabled will differ between parts. Calculate the
+			 * physical cpu number using cluster information instead.
+			 */
+			ret = populate_physical_mask(monitor_np, &monitor->mask,
+						     info->cluster_info);
+			if (ret < 0) {
+				dev_err_probe(&sdev->dev, ret, "failed to populate cpu mask\n");
+				goto err;
+			}
+
+			monitor->freq_map = init_cpufreq_memfreq_map(&sdev->dev, memory, monitor_np,
+								     &monitor->freq_map_len);
+			if (IS_ERR(monitor->freq_map)) {
+				dev_err_probe(&sdev->dev, PTR_ERR(monitor->freq_map),
+					      "failed to populate cpufreq-memfreq map\n");
+				goto err;
+			}
+
+			strscpy(monitor->mon_name, name, sizeof(monitor->mon_name));
+			monitor->mon_idx = memory->monitor_cnt;
+
+			memory->monitor[memory->monitor_cnt++] = monitor;
+		} while (1);
+
+		if (!memory->monitor_cnt) {
+			ret = -EINVAL;
+			dev_err_probe(&sdev->dev, ret, "failed to find monitor nodes\n");
+			goto err;
+		}
+	} while (1);
+
+	if (!info->memory_cnt) {
+		ret = -EINVAL;
+		dev_err_probe(&sdev->dev, ret, "failed to find memory nodes\n");
+	}
+
+err:
+	of_node_put(sdev->handle->dev->of_node);
+
+	return ret;
+}
+
+static int configure_cpucp_common_events(struct scmi_memlat_info *info)
+{
+	const struct qcom_scmi_vendor_ops *ops = info->ops;
+	u8 ev_map[NUM_COMMON_EVS];
+	struct ev_map_msg msg;
+	int ret;
+
+	memset(ev_map, 0xFF, NUM_COMMON_EVS);
+
+	msg.num_evs = NUM_COMMON_EVS;
+	msg.hw_type = INVALID_IDX;
+	msg.cid[INST_IDX] = EV_INST_RETIRED;
+	msg.cid[CYC_IDX] = EV_CPU_CYCLES;
+	msg.cid[CONST_CYC_IDX] = INVALID_IDX;
+	msg.cid[FE_STALL_IDX] = INVALID_IDX;
+	msg.cid[BE_STALL_IDX] = INVALID_IDX;
+
+	ret = ops->set_param(info->ph, &msg, MEMLAT_ALGO_STR, MEMLAT_SET_COMMON_EV_MAP,
+			     sizeof(msg));
+	return ret;
+}
+
+static int configure_cpucp_grp(struct device *dev, struct scmi_memlat_info *info, int memory_index)
+{
+	const struct qcom_scmi_vendor_ops *ops = info->ops;
+	struct scmi_memory_info *memory = info->memory[memory_index];
+	struct ev_map_msg ev_msg;
+	u8 ev_map[NUM_GRP_EVS];
+	struct node_msg msg;
+	int ret;
+
+	msg.cpumask = 0;
+	msg.hw_type = memory->hw_type;
+	msg.mon_type = 0;
+	msg.mon_idx = 0;
+	ret = ops->set_param(info->ph, &msg, MEMLAT_ALGO_STR, MEMLAT_SET_MEM_GROUP, sizeof(msg));
+	if (ret < 0) {
+		dev_err_probe(dev, ret, "failed to configure mem type %d\n", memory->hw_type);
+		return ret;
+	}
+
+	memset(ev_map, 0xFF, NUM_GRP_EVS);
+	ev_msg.num_evs = NUM_GRP_EVS;
+	ev_msg.hw_type = memory->hw_type;
+	ev_msg.cid[MISS_IDX] = EV_L2_D_RFILL;
+	ev_msg.cid[WB_IDX] = INVALID_IDX;
+	ev_msg.cid[ACC_IDX] = INVALID_IDX;
+	ret = ops->set_param(info->ph, &ev_msg, MEMLAT_ALGO_STR, MEMLAT_SET_GRP_EV_MAP,
+			     sizeof(ev_msg));
+	if (ret < 0) {
+		dev_err_probe(dev, ret,
+			      "failed to configure event map for mem type %d\n", memory->hw_type);
+		return ret;
+	}
+
+	return ret;
+}
+
+static int configure_cpucp_mon(struct device *dev, struct scmi_memlat_info *info,
+			       int memory_index, int monitor_index)
+{
+	const struct qcom_scmi_vendor_ops *ops = info->ops;
+	struct scmi_memory_info *memory = info->memory[memory_index];
+	struct scmi_monitor_info *monitor = memory->monitor[monitor_index];
+	struct scalar_param_msg scalar_msg;
+	struct map_param_msg map_msg;
+	struct node_msg msg;
+	int ret;
+	int i;
+
+	msg.cpumask = monitor->mask;
+	msg.hw_type = memory->hw_type;
+	msg.mon_type = monitor->mon_type;
+	msg.mon_idx = monitor->mon_idx;
+	strscpy(msg.mon_name, monitor->mon_name, sizeof(msg.mon_name));
+	ret = ops->set_param(info->ph, &msg, MEMLAT_ALGO_STR, MEMLAT_SET_MONITOR, sizeof(msg));
+	if (ret < 0) {
+		dev_err_probe(dev, ret, "failed to configure monitor %s\n", monitor->mon_name);
+		return ret;
+	}
+
+	scalar_msg.hw_type = memory->hw_type;
+	scalar_msg.mon_idx = monitor->mon_idx;
+	scalar_msg.val = monitor->ipm_ceil;
+	ret = ops->set_param(info->ph, &scalar_msg, MEMLAT_ALGO_STR, MEMLAT_IPM_CEIL,
+			     sizeof(scalar_msg));
+	if (ret < 0) {
+		dev_err_probe(dev, ret, "failed to set ipm ceil for %s\n", monitor->mon_name);
+		return ret;
+	}
+
+	map_msg.hw_type = memory->hw_type;
+	map_msg.mon_idx = monitor->mon_idx;
+	map_msg.nr_rows = monitor->freq_map_len;
+	for (i = 0; i < monitor->freq_map_len; i++) {
+		map_msg.tbl[i].v1 = monitor->freq_map[i].cpufreq_mhz;
+		map_msg.tbl[i].v2 = monitor->freq_map[i].memfreq_khz;
+	}
+	ret = ops->set_param(info->ph, &map_msg, MEMLAT_ALGO_STR, MEMLAT_MON_FREQ_MAP,
+			     sizeof(map_msg));
+	if (ret < 0) {
+		dev_err_probe(dev, ret, "failed to configure freq_map for %s\n", monitor->mon_name);
+		return ret;
+	}
+
+	scalar_msg.hw_type = memory->hw_type;
+	scalar_msg.mon_idx = monitor->mon_idx;
+	scalar_msg.val = memory->min_freq;
+	ret = ops->set_param(info->ph, &scalar_msg, MEMLAT_ALGO_STR, MEMLAT_SET_MIN_FREQ,
+			     sizeof(scalar_msg));
+	if (ret < 0) {
+		dev_err_probe(dev, ret, "failed to set min_freq for %s\n", monitor->mon_name);
+		return ret;
+	}
+
+	scalar_msg.hw_type = memory->hw_type;
+	scalar_msg.mon_idx = monitor->mon_idx;
+	scalar_msg.val = memory->max_freq;
+	ret = ops->set_param(info->ph, &scalar_msg, MEMLAT_ALGO_STR, MEMLAT_SET_MAX_FREQ,
+			     sizeof(scalar_msg));
+	if (ret < 0)
+		dev_err_probe(dev, ret, "failed to set max_freq for %s\n", monitor->mon_name);
+
+	return ret;
+}
+
+static int cpucp_memlat_init(struct scmi_device *sdev)
+{
+	const struct scmi_handle *handle = sdev->handle;
+	const struct qcom_scmi_vendor_ops *ops;
+	struct scmi_protocol_handle *ph;
+	struct scmi_memlat_info *info;
+	u32 cpucp_freq_method = CPUCP_DEFAULT_FREQ_METHOD;
+	u32 cpucp_sample_ms = CPUCP_DEFAULT_SAMPLING_PERIOD_MS;
+	int ret, i, j;
+
+	if (!handle)
+		return -ENODEV;
+
+	ops = handle->devm_protocol_get(sdev, QCOM_SCMI_VENDOR_PROTOCOL, &ph);
+	if (IS_ERR(ops))
+		return PTR_ERR(ops);
+
+	info = devm_kzalloc(&sdev->dev, sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	ret = process_scmi_memlat_of_node(sdev, info);
+	if (ret)
+		return ret;
+
+	info->ph = ph;
+	info->ops = ops;
+
+	/* Configure common events ids */
+	ret = configure_cpucp_common_events(info);
+	if (ret < 0) {
+		dev_err_probe(&sdev->dev, ret, "failed to configure common events\n");
+		return ret;
+	}
+
+	for (i = 0; i < info->memory_cnt; i++) {
+		/* Configure per group parameters */
+		ret = configure_cpucp_grp(&sdev->dev, info, i);
+		if (ret < 0)
+			return ret;
+
+		for (j = 0; j < info->memory[i]->monitor_cnt; j++) {
+			/* Configure per monitor parameters */
+			ret = configure_cpucp_mon(&sdev->dev, info, i, j);
+			if (ret < 0)
+				return ret;
+		}
+	}
+
+	/* Set loop sampling time */
+	ret = ops->set_param(ph, &cpucp_sample_ms, MEMLAT_ALGO_STR, MEMLAT_SAMPLE_MS,
+			     sizeof(cpucp_sample_ms));
+	if (ret < 0) {
+		dev_err_probe(&sdev->dev, ret, "failed to set sample_ms\n");
+		return ret;
+	}
+
+	/* Set the effective cpu frequency calculation method */
+	ret = ops->set_param(ph, &cpucp_freq_method, MEMLAT_ALGO_STR,
+			     MEMLAT_SET_EFFECTIVE_FREQ_METHOD, sizeof(cpucp_freq_method));
+	if (ret < 0) {
+		dev_err_probe(&sdev->dev, ret, "failed to set effective frequency calc method\n");
+		return ret;
+	}
+
+	/* Start sampling and voting timer */
+	ret = ops->start_activity(ph, NULL, MEMLAT_ALGO_STR, MEMLAT_START_TIMER, 0);
+	if (ret < 0)
+		dev_err_probe(&sdev->dev, ret, "failed to start memory group timer\n");
+
+	return ret;
+}
+
+static int scmi_client_probe(struct scmi_device *sdev)
+{
+	return cpucp_memlat_init(sdev);
+}
+
+static const struct scmi_device_id scmi_id_table[] = {
+	{ .protocol_id = QCOM_SCMI_VENDOR_PROTOCOL, .name = "qcom_scmi_vendor_protocol" },
+	{ },
+};
+MODULE_DEVICE_TABLE(scmi, scmi_id_table);
+
+static struct scmi_driver qcom_scmi_client_drv = {
+	.name		= "qcom-scmi-driver",
+	.probe		= scmi_client_probe,
+	.id_table	= scmi_id_table,
+};
+module_scmi_driver(qcom_scmi_client_drv);
+
+MODULE_DESCRIPTION("QTI SCMI client driver");
+MODULE_LICENSE("GPL");
-- 
2.34.1




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