[RFC 4/7] soc: qcom: Utilize qcom scmi vendor protocol for bus dvfs

[Sibi Sankar]

From: Shivnandan Kumar <quic_kshivnan@xxxxxxxxxxx>

This patch introduces a client driver that interacts with the SCMI QCOM
vendor protocol and passes on the required tuneables to start various
features running on the SCMI controller.

Signed-off-by: Shivnandan Kumar <quic_kshivnan@xxxxxxxxxxx>
Co-developed-by: Ramakrishna Gottimukkula <quic_rgottimu@xxxxxxxxxxx>
Signed-off-by: Ramakrishna Gottimukkula <quic_rgottimu@xxxxxxxxxxx>
Co-developed-by: Amir Vajid <avajid@xxxxxxxxxxx>
Signed-off-by: Amir Vajid <avajid@xxxxxxxxxxx>
Co-developed-by: Sibi Sankar <quic_sibis@xxxxxxxxxxx>
Signed-off-by: Sibi Sankar <quic_sibis@xxxxxxxxxxx>
---
 drivers/soc/qcom/Kconfig            |  10 +
 drivers/soc/qcom/Makefile           |   1 +
 drivers/soc/qcom/qcom_scmi_client.c | 486 ++++++++++++++++++++++++++++
 3 files changed, 497 insertions(+)
 create mode 100644 drivers/soc/qcom/qcom_scmi_client.c

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index c6ca4de42586..1530558aebfb 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -264,6 +264,16 @@ config QCOM_ICC_BWMON
 	  the fixed bandwidth votes from cpufreq (CPU nodes) thus achieve high
 	  memory throughput even with lower CPU frequencies.
 
+config QCOM_SCMI_CLIENT
+	tristate "Qualcomm Technologies Inc. SCMI client driver"
+	depends on QCOM_SCMI_VENDOR_PROTOCOL || COMPILE_TEST
+	default n
+	help
+	  SCMI client driver registers for SCMI QCOM vendor protocol.
+
+	  This driver interacts with the vendor protocol and passes on the required
+	  tuneables to start various features running on the SCMI controller.
+
 config QCOM_INLINE_CRYPTO_ENGINE
 	tristate
 	select QCOM_SCM
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 05b3d54e8dc9..c2a51293c886 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -32,5 +32,6 @@ 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
diff --git a/drivers/soc/qcom/qcom_scmi_client.c b/drivers/soc/qcom/qcom_scmi_client.c
new file mode 100644
index 000000000000..418aa7900496
--- /dev/null
+++ b/drivers/soc/qcom/qcom_scmi_client.c
@@ -0,0 +1,486 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2024, The Linux Foundation. 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>
+
+#define MAX_MEMORY_TYPES	3
+#define MEMLAT_ALGO_STR		0x74616C6D656D /* "memlat" */
+#define INVALID_IDX		0xFF
+#define MAX_NAME_LEN		20
+#define MAX_MAP_ENTRIES		6
+#define MAX_MONITOR_CNT		4
+#define SCMI_VENDOR_MSG_START	3
+#define SCMI_VENDOR_MSG_MODULE_START	16
+
+enum scmi_memlat_protocol_cmd {
+	MEMLAT_SET_LOG_LEVEL = SCMI_VENDOR_MSG_START,
+	MEMLAT_FLUSH_LOGBUF,
+	MEMLAT_SET_MEM_GROUP = SCMI_VENDOR_MSG_MODULE_START,
+	MEMLAT_SET_MONITOR,
+	MEMLAT_SET_COMMON_EV_MAP,
+	MEMLAT_SET_GRP_EV_MAP,
+	MEMLAT_ADAPTIVE_LOW_FREQ,
+	MEMLAT_ADAPTIVE_HIGH_FREQ,
+	MEMLAT_GET_ADAPTIVE_CUR_FREQ,
+	MEMLAT_IPM_CEIL,
+	MEMLAT_FE_STALL_FLOOR,
+	MEMLAT_BE_STALL_FLOOR,
+	MEMLAT_WB_PCT,
+	MEMLAT_IPM_FILTER,
+	MEMLAT_FREQ_SCALE_PCT,
+	MEMLAT_FREQ_SCALE_CEIL_MHZ,
+	MEMLAT_FREQ_SCALE_FLOOR_MHZ,
+	MEMLAT_SAMPLE_MS,
+	MEMLAT_MON_FREQ_MAP,
+	MEMLAT_SET_MIN_FREQ,
+	MEMLAT_SET_MAX_FREQ,
+	MEMLAT_GET_CUR_FREQ,
+	MEMLAT_START_TIMER,
+	MEMLAT_STOP_TIMER,
+	MEMLAT_GET_TIMESTAMP,
+	MEMLAT_MAX_MSG
+};
+
+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,
+	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];
+	int memory_cnt;
+};
+
+static int get_mask(struct device_node *np, u32 *mask)
+{
+	struct device_node *dev_phandle;
+	struct device *cpu_dev;
+	int cpu, i = 0;
+	int ret = -ENODEV;
+
+	dev_phandle = of_parse_phandle(np, "qcom,cpulist", i++);
+	while (dev_phandle) {
+		for_each_possible_cpu(cpu) {
+			cpu_dev = get_cpu_device(cpu);
+			if (cpu_dev && cpu_dev->of_node == dev_phandle) {
+				*mask |= BIT(cpu);
+				ret = 0;
+				break;
+			}
+		}
+		dev_phandle = of_parse_phandle(np, "qcom,cpulist", i++);
+	}
+
+	return ret;
+}
+
+static struct cpufreq_memfreq_map *init_cpufreq_memfreq_map(struct device *dev,
+							    struct device_node *of_node,
+							    u32 *cnt)
+{
+	int len, nf, i, j;
+	u32 data;
+	struct cpufreq_memfreq_map *tbl;
+	int ret;
+
+	if (!of_find_property(of_node, "qcom,cpufreq-memfreq-tbl", &len))
+		return NULL;
+	len /= sizeof(data);
+
+	if (len % 2 || len == 0)
+		return NULL;
+	nf = len / 2;
+
+	tbl = devm_kzalloc(dev, (nf + 1) * sizeof(struct cpufreq_memfreq_map),
+			   GFP_KERNEL);
+	if (!tbl)
+		return NULL;
+
+	for (i = 0, j = 0; i < nf; i++, j += 2) {
+		ret = of_property_read_u32_index(of_node, "qcom,cpufreq-memfreq-tbl",
+						 j, &data);
+		if (ret < 0)
+			return NULL;
+		tbl[i].cpufreq_mhz = data / 1000;
+
+		ret = of_property_read_u32_index(of_node, "qcom,cpufreq-memfreq-tbl",
+						 j + 1, &data);
+		if (ret < 0)
+			return NULL;
+
+		tbl[i].memfreq_khz = data;
+		pr_debug("Entry%d CPU:%u, Mem:%u\n", i, tbl[i].cpufreq_mhz,
+			 tbl[i].memfreq_khz);
+	}
+	*cnt = nf;
+	tbl[i].cpufreq_mhz = 0;
+
+	return tbl;
+}
+
+static int process_scmi_memlat_of_node(struct scmi_device *sdev, struct scmi_memlat_info *info)
+{
+	struct device_node *memlat_np, *memory_np, *monitor_np;
+	struct scmi_memory_info *memory;
+	struct scmi_monitor_info *monitor;
+	int ret = 0, i = 0, j;
+	u32 memfreq[2];
+
+	of_node_get(sdev->handle->dev->of_node);
+	memlat_np = of_find_node_by_name(sdev->handle->dev->of_node, "memlat");
+
+	info->memory_cnt = of_get_child_count(memlat_np);
+	if (info->memory_cnt <= 0)
+		pr_err("No memory nodes present\n");
+
+	for_each_child_of_node(memlat_np, memory_np) {
+		memory = devm_kzalloc(&sdev->dev, sizeof(*memory), GFP_KERNEL);
+		if (!memory) {
+			ret = -ENOMEM;
+			goto err;
+		}
+
+		ret = of_property_read_u32(memory_np, "reg", &memory->hw_type);
+		if (ret) {
+			pr_err("Failed to read memory type\n");
+			goto err;
+		}
+
+		memory->monitor_cnt = of_get_child_count(memory_np);
+		if (memory->monitor_cnt <= 0) {
+			pr_err("No monitor nodes present\n");
+			ret = -EINVAL;
+			goto err;
+		}
+
+		ret = of_property_read_u32_array(memory_np, "freq-table-khz", memfreq, 2);
+		if (ret && (ret != -EINVAL)) {
+			pr_err("Failed to read min/max freq %d\n", ret);
+			goto err;
+		}
+
+		memory->min_freq = memfreq[0];
+		memory->max_freq = memfreq[1];
+		info->memory[i] = memory;
+		j = 0;
+		i++;
+
+		for_each_child_of_node(memory_np, monitor_np) {
+			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-mon")) ? 1 : 0;
+			monitor->ipm_ceil = (of_property_read_bool(monitor_np, "qcom,compute-mon")) ? 0 : 20000000;
+
+			if (get_mask(monitor_np, &monitor->mask)) {
+				pr_err("Failed to populate cpu mask %d\n", ret);
+				goto err;
+			}
+
+			monitor->freq_map = init_cpufreq_memfreq_map(&sdev->dev, monitor_np,
+								     &monitor->freq_map_len);
+			snprintf(monitor->mon_name, MAX_NAME_LEN, "monitor-%d", j);
+			monitor->mon_idx = j;
+
+			memory->monitor[j] = monitor;
+			j++;
+		}
+	}
+
+	return 0;
+
+err:
+	of_node_put(memlat_np);
+
+	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[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 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) {
+		pr_err("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) {
+		pr_err("Failed to configure event map for mem type %d\n", memory->hw_type);
+		return ret;
+	}
+
+	return ret;
+}
+
+static int configure_cpucp_mon(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) {
+		pr_err("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) {
+		pr_err("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 / 1000;
+	}
+	ret = ops->set_param(info->ph, &map_msg, MEMLAT_ALGO_STR, MEMLAT_MON_FREQ_MAP,
+			     sizeof(map_msg));
+	if (ret < 0) {
+		pr_err("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) {
+		pr_err("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)
+		pr_err("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_sample_ms = 8;
+	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)
+		pr_err("Failed to configure common events: %d\n", ret);
+
+	info->ph = ph;
+	info->ops = ops;
+
+	ret = configure_cpucp_common_events(info);
+	if (ret < 0)
+		pr_err("Failed to configure common events: %d\n", ret);
+
+	for (i = 0; i < info->memory_cnt; i++) {
+		ret = configure_cpucp_grp(info, i);
+		if (ret < 0)
+			pr_err("Failed to configure mem group: %d\n", ret);
+
+		for (j = 0; j < info->memory[i]->monitor_cnt; j++) {
+			/* Configure per monitor parameters */
+			ret = configure_cpucp_mon(info, i, j);
+			if (ret < 0)
+				pr_err("Failed to configure monitor: %d\n", ret);
+		}
+	}
+
+	ret = ops->set_param(ph, &cpucp_sample_ms, MEMLAT_ALGO_STR, MEMLAT_SAMPLE_MS,
+			     sizeof(cpucp_sample_ms));
+	if (ret < 0)
+		pr_err("Failed to set cpucp sample_ms ret = %d\n", ret);
+
+	/* Start sampling and voting timer */
+	ret = ops->start_activity(ph, NULL, MEMLAT_ALGO_STR, MEMLAT_START_TIMER, 0);
+	if (ret < 0)
+		pr_err("Error in starting the mem group timer %d\n", ret);
+
+	dev_set_drvdata(&sdev->dev, info);
+
+	return ret;
+}
+
+static int scmi_client_probe(struct scmi_device *sdev)
+{
+	cpucp_memlat_init(sdev);
+
+	return 0;
+}
+
+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