Re: [PATCH v5 2/4] soc: qcom: Add SoC sleep stats driver

Guenter Roeck
2020-08-22T15:45:46Z

On Wed, Mar 18, 2020 at 09:59:16AM +0530, Maulik Shah wrote:
> From: Mahesh Sivasubramanian <msivasub@codeaurora.org>
>
> Let's add a driver to read the 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 | 9 ++
> drivers/soc/qcom/Makefile | 1 +
> drivers/soc/qcom/soc_sleep_stats.c | 244 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 254 insertions(+)
> create mode 100644 drivers/soc/qcom/soc_sleep_stats.c
>
> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
> index d0a73e7..08bc0df3 100644
> --- a/drivers/soc/qcom/Kconfig
> +++ b/drivers/soc/qcom/Kconfig
> @@ -185,6 +185,15 @@ 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

Otherwise causes compile error if QCOM_SMEM=n.

Guenter

> + 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 9fb35c8..e6bd052 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..0db7c3d
> --- /dev/null
> +++ b/drivers/soc/qcom/soc_sleep_stats.c
> @@ -0,0 +1,244 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2011-2020, 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_ADDR 0x0
> +#define COUNT_ADDR 0x4
> +#define LAST_ENTERED_AT_ADDR 0x8
> +#define LAST_EXITED_AT_ADDR 0x10
> +#define ACCUMULATED_ADDR 0x18
> +#define CLIENT_VOTES_ADDR 0x1c
> +
> +struct subsystem_data {
> + const char *name;
> + u32 smem_item;
> + u32 pid;
> +};
> +
> +static struct subsystem_data subsystems[] = {
> + { "modem", 605, 1 },
> + { "adsp", 606, 2 },
> + { "cdsp", 607, 5 },
> + { "slpi", 608, 3 },
> + { "gpu", 609, 0 },
> + { "display", 610, 0 },
> +};
> +
> +struct stats_config {
> + unsigned int offset_addr;
> + unsigned int num_records;
> + bool appended_stats_avail;
> +};
> +
> +struct stats_prv_data {
> + const struct stats_config *config;
> + void __iomem *reg;
> +};
> +
> +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 print_sleep_stats(struct seq_file *s, 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 subsystem_sleep_stats_show(struct seq_file *s, void *d)
> +{
> + struct subsystem_data *subsystem = s->private;
> + struct sleep_stats *stat;
> +
> + stat = qcom_smem_get(subsystem->pid, subsystem->smem_item, NULL);
> + if (IS_ERR(stat))
> + return PTR_ERR(stat);
> +
> + print_sleep_stats(s, stat);
> +
> + return 0;
> +}
> +
> +static int soc_sleep_stats_show(struct seq_file *s, void *d)
> +{
> + struct stats_prv_data *prv_data = s->private;
> + void __iomem *reg = prv_data->reg;
> + struct sleep_stats stat;
> +
> + stat.count = readl(reg + COUNT_ADDR);
> + stat.last_entered_at = readq(reg + LAST_ENTERED_AT_ADDR);
> + stat.last_exited_at = readq(reg + LAST_EXITED_AT_ADDR);
> + stat.accumulated = readq(reg + ACCUMULATED_ADDR);
> +
> + print_sleep_stats(s, &stat);
> +
> + if (prv_data->config->appended_stats_avail) {
> + struct appended_stats app_stat;
> +
> + app_stat.client_votes = readl(reg + CLIENT_VOTES_ADDR);
> + seq_printf(s, "Client_votes = %#x\n", app_stat.client_votes);
> + }
> +
> + return 0;
> +}
> +
> +DEFINE_SHOW_ATTRIBUTE(soc_sleep_stats);
> +DEFINE_SHOW_ATTRIBUTE(subsystem_sleep_stats);
> +
> +static struct dentry *create_debugfs_entries(void __iomem *reg,
> + struct stats_prv_data *prv_data)
> +{
> + struct dentry *root;
> + struct sleep_stats *stat;
> + char stat_type[sizeof(u32) + 1] = {0};
> + u32 offset, type;
> + int i;
> +
> + root = debugfs_create_dir("qcom_sleep_stats", NULL);
> +
> + for (i = 0; i < prv_data[0].config->num_records; i++) {
> + offset = STAT_TYPE_ADDR + (i * sizeof(struct sleep_stats));
> +
> + if (prv_data[0].config->appended_stats_avail)
> + offset += i * sizeof(struct appended_stats);
> +
> + prv_data[i].reg = reg + offset;
> +
> + type = readl(prv_data[i].reg);
> + memcpy(stat_type, &type, sizeof(u32));
> + debugfs_create_file(stat_type, 0444, root,
> + &prv_data[i],
> + &soc_sleep_stats_fops);
> + }
> +
> + 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, 0444, root,
> + &subsystems[i],
> + &subsystem_sleep_stats_fops);
> + }
> +
> + return root;
> +}
> +
> +static int soc_sleep_stats_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + void __iomem *reg;
> + void __iomem *offset_addr;
> + phys_addr_t stats_base;
> + resource_size_t stats_size;
> + struct dentry *root;
> + const struct stats_config *config;
> + struct stats_prv_data *prv_data;
> + 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);
> +
> + offset_addr = ioremap(res->start + config->offset_addr, sizeof(u32));
> + if (IS_ERR(offset_addr))
> + return PTR_ERR(offset_addr);
> +
> + stats_base = res->start | readl_relaxed(offset_addr);
> + stats_size = resource_size(res);
> + iounmap(offset_addr);
> +
> + reg = devm_ioremap(&pdev->dev, stats_base, stats_size);
> + if (!reg)
> + return -ENOMEM;
> +
> + prv_data = devm_kzalloc(&pdev->dev, config->num_records *
> + sizeof(struct stats_prv_data), GFP_KERNEL);
> + if (!prv_data)
> + return -ENOMEM;
> +
> + for (i = 0; i < config->num_records; i++)
> + prv_data[i].config = config;
> +
> + root = create_debugfs_entries(reg, prv_data);
> + platform_set_drvdata(pdev, root);
> +
> + return 0;
> +}
> +
> +static int 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 = {
> + .offset_addr = 0x14,
> + .num_records = 2,
> + .appended_stats_avail = true,
> +};
> +
> +static const struct stats_config rpmh_data = {
> + .offset_addr = 0x4,
> + .num_records = 3,
> + .appended_stats_avail = false,
> +};
> +
> +static const struct of_device_id 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_driver = {
> + .probe = soc_sleep_stats_probe,
> + .remove = soc_sleep_stats_remove,
> + .driver = {
> + .name = "soc_sleep_stats",
> + .of_match_table = soc_sleep_stats_table,
> + },
> +};
> +module_platform_driver(soc_sleep_stats_driver);
> +
> +MODULE_DESCRIPTION("Qualcomm Technologies, Inc. (QTI) SoC Sleep Stats driver");
> +MODULE_LICENSE("GPL v2");