[PATCH v9 2/5] soc: qcom: Add SoC sleep stats driver

Maulik Shah
2021-09-06T05:28:33Z

From: Mahesh Sivasubramanian <msivasub@codeaurora.org>

Let's add a driver to read the stats from remote processor and
export to debugfs.

The driver creates "qcom_sleep_stats" directory in debugfs and
adds files for various low power mode available. Below is sample
output with command

cat /sys/kernel/debug/qcom_sleep_stats/ddr
count = 0
Last Entered At = 0
Last Exited At = 0
Accumulated Duration = 0

Signed-off-by: Mahesh Sivasubramanian <msivasub@codeaurora.org>
Signed-off-by: Lina Iyer <ilina@codeaurora.org>
[mkshah: add subsystem sleep stats, create one file for each stat]
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
---
drivers/soc/qcom/Kconfig | 10 ++
drivers/soc/qcom/Makefile | 1 +
drivers/soc/qcom/soc_sleep_stats.c | 241 +++++++++++++++++++++++++++++++++++++
3 files changed, 252 insertions(+)
create mode 100644 drivers/soc/qcom/soc_sleep_stats.c

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index 79b568f..e80b63a 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -190,6 +190,16 @@ config QCOM_SOCINFO
Say yes here to support the Qualcomm socinfo driver, providing
information about the SoC to user space.

+config QCOM_SOC_SLEEP_STATS
+ tristate "Qualcomm Technologies, Inc. (QTI) SoC sleep stats driver"
+ depends on ARCH_QCOM && DEBUG_FS || COMPILE_TEST
+ depends on QCOM_SMEM
+ help
+ Qualcomm Technologies, Inc. (QTI) SoC sleep stats driver to read
+ the shared memory exported by the remote processor related to
+ various SoC level low power modes statistics and export to debugfs
+ interface.
+
config QCOM_WCNSS_CTRL
tristate "Qualcomm WCNSS control driver"
depends on ARCH_QCOM || COMPILE_TEST
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index ad675a6..5f30d74 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_QCOM_SMEM_STATE) += smem_state.o
obj-$(CONFIG_QCOM_SMP2P) += smp2p.o
obj-$(CONFIG_QCOM_SMSM) += smsm.o
obj-$(CONFIG_QCOM_SOCINFO) += socinfo.o
+obj-$(CONFIG_QCOM_SOC_SLEEP_STATS) += soc_sleep_stats.o
obj-$(CONFIG_QCOM_WCNSS_CTRL) += wcnss_ctrl.o
obj-$(CONFIG_QCOM_APR) += apr.o
obj-$(CONFIG_QCOM_LLCC) += llcc-qcom.o
diff --git a/drivers/soc/qcom/soc_sleep_stats.c b/drivers/soc/qcom/soc_sleep_stats.c
new file mode 100644
index 0000000..db28dd2
--- /dev/null
+++ b/drivers/soc/qcom/soc_sleep_stats.c
@@ -0,0 +1,241 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2011-2021, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/seq_file.h>
+
+#include <linux/soc/qcom/smem.h>
+#include <clocksource/arm_arch_timer.h>
+
+#define STAT_TYPE_OFFSET 0x0
+#define COUNT_OFFSET 0x4
+#define LAST_ENTERED_AT_OFFSET 0x8
+#define LAST_EXITED_AT_OFFSET 0x10
+#define ACCUMULATED_OFFSET 0x18
+#define CLIENT_VOTES_OFFSET 0x1c
+
+struct subsystem_data {
+ const char *name;
+ u32 smem_item;
+ u32 pid;
+};
+
+static const struct subsystem_data subsystems[] = {
+ { "modem", 605, 1 },
+ { "wpss", 605, 13 },
+ { "adsp", 606, 2 },
+ { "cdsp", 607, 5 },
+ { "slpi", 608, 3 },
+ { "gpu", 609, 0 },
+ { "display", 610, 0 },
+ { "adsp_island", 613, 2 },
+ { "slpi_island", 613, 3 },
+};
+
+struct stats_config {
+ size_t offset_addr;
+ size_t num_records;
+ bool appended_stats_avail;
+};
+
+struct stats_data {
+ bool appended_stats_avail;
+ void __iomem *base;
+};
+
+struct sleep_stats {
+ u32 stat_type;
+ u32 count;
+ u64 last_entered_at;
+ u64 last_exited_at;
+ u64 accumulated;
+};
+
+struct appended_stats {
+ u32 client_votes;
+ u32 reserved[3];
+};
+
+static void qcom_print_stats(struct seq_file *s, const struct sleep_stats *stat)
+{
+ u64 accumulated = stat->accumulated;
+ /*
+ * If a subsystem is in sleep when reading the sleep stats adjust
+ * the accumulated sleep duration to show actual sleep time.
+ */
+ if (stat->last_entered_at > stat->last_exited_at)
+ accumulated += arch_timer_read_counter() - stat->last_entered_at;
+
+ seq_printf(s, "Count: %u\n", stat->count);
+ seq_printf(s, "Last Entered At: %llu\n", stat->last_entered_at);
+ seq_printf(s, "Last Exited At: %llu\n", stat->last_exited_at);
+ seq_printf(s, "Accumulated Duration: %llu\n", accumulated);
+}
+
+static int qcom_subsystem_sleep_stats_show(struct seq_file *s, void *unused)
+{
+ struct subsystem_data *subsystem = s->private;
+ struct sleep_stats *stat;
+
+ /* Items are allocated lazily, so lookup pointer each time */
+ stat = qcom_smem_get(subsystem->pid, subsystem->smem_item, NULL);
+ if (IS_ERR(stat))
+ return -EIO;
+
+ qcom_print_stats(s, stat);
+
+ return 0;
+}
+
+static int qcom_soc_sleep_stats_show(struct seq_file *s, void *unused)
+{
+ struct stats_data *d = s->private;
+ void __iomem *reg = d->base;
+ struct sleep_stats stat;
+
+ memcpy_fromio(&stat, reg, sizeof(stat));
+ qcom_print_stats(s, &stat);
+
+ if (d->appended_stats_avail) {
+ struct appended_stats votes;
+
+ memcpy_fromio(&votes, reg + CLIENT_VOTES_OFFSET, sizeof(votes));
+ seq_printf(s, "Client Votes: %#x\n", votes.client_votes);
+ }
+
+ return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(qcom_soc_sleep_stats);
+DEFINE_SHOW_ATTRIBUTE(qcom_subsystem_sleep_stats);
+
+static void qcom_create_soc_sleep_stat_files(struct dentry *root, void __iomem *reg,
+ struct stats_data *d, u32 num_records)
+{
+ char stat_type[sizeof(u32) + 1] = {0};
+ u32 offset = 0, type;
+ int i, j;
+
+ for (i = 0; i < num_records; i++) {
+ d[i].base = reg + offset;
+
+ /*
+ * Read the low power mode name and create debugfs file for it.
+ * The names read could be of below,
+ * (may change depending on low power mode supported).
+ * For rpmh-sleep-stats: "aosd", "cxsd" and "ddr".
+ * For rpm-sleep-stats: "vmin" and "vlow".
+ */
+ type = readl(d[i].base);
+ for (j = 0; j < sizeof(u32); j++) {
+ stat_type[j] = type & 0xff;
+ type = type >> 8;
+ }
+ strim(stat_type);
+ debugfs_create_file(stat_type, 0400, root, &d[i],
+ &qcom_soc_sleep_stats_fops);
+
+ offset += sizeof(struct sleep_stats);
+ if (d[i].appended_stats_avail)
+ offset += sizeof(struct appended_stats);
+ }
+}
+
+static void qcom_create_subsystem_stat_files(struct dentry *root)
+{
+ const struct sleep_stats *stat;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(subsystems); i++) {
+ stat = qcom_smem_get(subsystems[i].pid, subsystems[i].smem_item, NULL);
+ if (IS_ERR(stat))
+ continue;
+
+ debugfs_create_file(subsystems[i].name, 0400, root, (void *)&subsystems[i],
+ &qcom_subsystem_sleep_stats_fops);
+ }
+}
+
+static int qcom_soc_sleep_stats_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ void __iomem *reg;
+ struct dentry *root;
+ const struct stats_config *config;
+ struct stats_data *d;
+ int i;
+
+ config = device_get_match_data(&pdev->dev);
+ if (!config)
+ return -ENODEV;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return PTR_ERR(res);
+
+ reg = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
+ if (!reg)
+ return -ENOMEM;
+
+ d = devm_kcalloc(&pdev->dev, config->num_records,
+ sizeof(*d), GFP_KERNEL);
+ if (!d)
+ return -ENOMEM;
+
+ for (i = 0; i < config->num_records; i++)
+ d[i].appended_stats_avail = config->appended_stats_avail;
+
+ root = debugfs_create_dir("qcom_sleep_stats", NULL);
+
+ qcom_create_subsystem_stat_files(root);
+ qcom_create_soc_sleep_stat_files(root, reg, d, config->num_records);
+
+ platform_set_drvdata(pdev, root);
+
+ return 0;
+}
+
+static int qcom_soc_sleep_stats_remove(struct platform_device *pdev)
+{
+ struct dentry *root = platform_get_drvdata(pdev);
+
+ debugfs_remove_recursive(root);
+
+ return 0;
+}
+
+static const struct stats_config rpm_data = {
+ .num_records = 2,
+ .appended_stats_avail = true,
+};
+
+static const struct stats_config rpmh_data = {
+ .num_records = 3,
+ .appended_stats_avail = false,
+};
+
+static const struct of_device_id qcom_soc_sleep_stats_table[] = {
+ { .compatible = "qcom,rpm-sleep-stats", .data = &rpm_data },
+ { .compatible = "qcom,rpmh-sleep-stats", .data = &rpmh_data },
+ { }
+};
+
+static struct platform_driver soc_sleep_stats = {
+ .probe = qcom_soc_sleep_stats_probe,
+ .remove = qcom_soc_sleep_stats_remove,
+ .driver = {
+ .name = "soc_sleep_stats",
+ .of_match_table = qcom_soc_sleep_stats_table,
+ },
+};
+module_platform_driver(soc_sleep_stats);
+
+MODULE_DESCRIPTION("Qualcomm Technologies, Inc. (QTI) SoC Sleep Stats driver");
+MODULE_LICENSE("GPL v2");