| Message ID | 2ef76ce292c059c144e559123a9a54201ae2d0cf.1681742910.git.quic_schowdhu@quicinc.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | soc: qcom: boot_stats: Add driver support for boot_stats | expand |
On 17/04/2023 16:08, Souradeep Chowdhury wrote: > All of Qualcomm's proprietary Android boot-loaders capture boot time > stats, like the time when the bootloader started execution and at what > point the bootloader handed over control to the kernel etc. in the IMEM > region. This information is captured in a specific format by this driver > by mapping a structure to the IMEM memory region and then accessing the > members of the structure to show the information within debugfs file. > This information is useful in verifying if the existing boot KPIs have > regressed or not. The information is shown in milliseconds, a sample > log from sm8450(waipio) device is as follows:- > > /sys/kernel/debug/146aa6b0.boot_stats # cat abl_time > 17898 ms > /sys/kernel/debug/146aa6b0.boot_stats # cat pre_abl_time > 2879 ms > > The Module Power Manager(MPM) sleep counter starts ticking at the PBL > stage and the timestamp generated by the sleep counter is logged by > the Qualcomm proprietary bootloader(ABL) at two points-> First when it > starts execution which is logged here as "pre_abl_time" and the second > when it is about to load the kernel logged as "abl_time". Documentation > details are also added in Documentation/ABI/testing/debugfs-driver-bootstat > > Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com> Hi, [...] > + > +static int boot_stats_probe(struct platform_device *pdev) > +{ > + struct device *bootstat_dev = &pdev->dev; > + struct bs_data *drvdata; > + > + drvdata = devm_kzalloc(bootstat_dev, sizeof(*drvdata), GFP_KERNEL); > + platform_set_drvdata(pdev, drvdata); > + > + drvdata->dbg_dir = debugfs_create_dir(dev_name(bootstat_dev), NULL); This might be better as just "qcom_boot_stats", rather than including the address. [...] > + > +static const struct of_device_id boot_stats_dt_match[] = { > + { .compatible = "qcom,sm8450-bootstats" }, This driver doesn't only support sm8450, I've tested this on sdm845 and it works just fine. Can we use a generic compatible here instead? > + { } > +}; > +MODULE_DEVICE_TABLE(of, boot_stats_dt_match); > + > +static struct platform_driver boot_stat_driver = { > + .probe = boot_stats_probe, > + .remove_new = boot_stats_remove, > + .driver = { > + .name = "qcom-boot-stats", > + .of_match_table = boot_stats_dt_match, > + }, > +}; > +module_platform_driver(boot_stat_driver); > + > +MODULE_DESCRIPTION("Qualcomm Technologies Inc. Boot Stat driver"); > +MODULE_LICENSE("GPL"); > -- > 2.7.4 >
On 5/4/2023 4:23 AM, Caleb Connolly wrote: > > > On 17/04/2023 16:08, Souradeep Chowdhury wrote: >> All of Qualcomm's proprietary Android boot-loaders capture boot time >> stats, like the time when the bootloader started execution and at what >> point the bootloader handed over control to the kernel etc. in the IMEM >> region. This information is captured in a specific format by this driver >> by mapping a structure to the IMEM memory region and then accessing the >> members of the structure to show the information within debugfs file. >> This information is useful in verifying if the existing boot KPIs have >> regressed or not. The information is shown in milliseconds, a sample >> log from sm8450(waipio) device is as follows:- >> >> /sys/kernel/debug/146aa6b0.boot_stats # cat abl_time >> 17898 ms >> /sys/kernel/debug/146aa6b0.boot_stats # cat pre_abl_time >> 2879 ms >> >> The Module Power Manager(MPM) sleep counter starts ticking at the PBL >> stage and the timestamp generated by the sleep counter is logged by >> the Qualcomm proprietary bootloader(ABL) at two points-> First when it >> starts execution which is logged here as "pre_abl_time" and the second >> when it is about to load the kernel logged as "abl_time". Documentation >> details are also added in Documentation/ABI/testing/debugfs-driver-bootstat >> >> Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com> > > Hi, > > [...] >> + >> +static int boot_stats_probe(struct platform_device *pdev) >> +{ >> + struct device *bootstat_dev = &pdev->dev; >> + struct bs_data *drvdata; >> + >> + drvdata = devm_kzalloc(bootstat_dev, sizeof(*drvdata), GFP_KERNEL); >> + platform_set_drvdata(pdev, drvdata); >> + >> + drvdata->dbg_dir = debugfs_create_dir(dev_name(bootstat_dev), NULL); > > This might be better as just "qcom_boot_stats", rather than including > the address. We usually use the dev_name to represent the one to one correspondence of the debugfs file with the device. Will create the root dir as "qcom_boot_stats" and push the dev_name dir inside it. > > [...] >> + >> +static const struct of_device_id boot_stats_dt_match[] = { >> + { .compatible = "qcom,sm8450-bootstats" }, > > This driver doesn't only support sm8450, I've tested this on sdm845 and > it works just fine. Can we use a generic compatible here instead? We can add soc specific compatibles here to extend support for other socs. This also captures the SoCs for which the driver is supported which won't be the case if we use a generic compatible. >> + { } >> +}; >> +MODULE_DEVICE_TABLE(of, boot_stats_dt_match); >> + >> +static struct platform_driver boot_stat_driver = { >> + .probe = boot_stats_probe, >> + .remove_new = boot_stats_remove, >> + .driver = { >> + .name = "qcom-boot-stats", >> + .of_match_table = boot_stats_dt_match, >> + }, >> +}; >> +module_platform_driver(boot_stat_driver); >> + >> +MODULE_DESCRIPTION("Qualcomm Technologies Inc. Boot Stat driver"); >> +MODULE_LICENSE("GPL"); >> -- >> 2.7.4 >> >
On 17/04/2023 18:08, Souradeep Chowdhury wrote: > All of Qualcomm's proprietary Android boot-loaders capture boot time > stats, like the time when the bootloader started execution and at what > point the bootloader handed over control to the kernel etc. in the IMEM > region. This information is captured in a specific format by this driver > by mapping a structure to the IMEM memory region and then accessing the > members of the structure to show the information within debugfs file. > This information is useful in verifying if the existing boot KPIs have > regressed or not. The information is shown in milliseconds, a sample > log from sm8450(waipio) device is as follows:- > > /sys/kernel/debug/146aa6b0.boot_stats # cat abl_time > 17898 ms > /sys/kernel/debug/146aa6b0.boot_stats # cat pre_abl_time > 2879 ms > > The Module Power Manager(MPM) sleep counter starts ticking at the PBL > stage and the timestamp generated by the sleep counter is logged by > the Qualcomm proprietary bootloader(ABL) at two points-> First when it > starts execution which is logged here as "pre_abl_time" and the second > when it is about to load the kernel logged as "abl_time". Documentation > details are also added in Documentation/ABI/testing/debugfs-driver-bootstat > > Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com> > --- > Documentation/ABI/testing/debugfs-driver-bootstat | 17 ++++ > drivers/soc/qcom/Kconfig | 9 ++ > drivers/soc/qcom/Makefile | 1 + > drivers/soc/qcom/boot_stats.c | 101 ++++++++++++++++++++++ > 4 files changed, 128 insertions(+) > create mode 100644 Documentation/ABI/testing/debugfs-driver-bootstat > create mode 100644 drivers/soc/qcom/boot_stats.c > > diff --git a/Documentation/ABI/testing/debugfs-driver-bootstat b/Documentation/ABI/testing/debugfs-driver-bootstat > new file mode 100644 > index 0000000..2543029 > --- /dev/null > +++ b/Documentation/ABI/testing/debugfs-driver-bootstat > @@ -0,0 +1,17 @@ > +What: /sys/kernel/debug/...stats/pre_abl_time > +Date: April 2023 > +Contact: Souradeep Chowdhury <quic_schowdhu@quicinc.com> > +Description: > + This file is used to read the KPI value pre abl time. > + It shows the time in milliseconds from the starting > + point of PBL to the point when the control shifted > + to ABL(Qualcomm proprietary bootloader). > + > +What: /sys/kernel/debug/...stats/abl_time > +Date: April 2023 > +Contact: Souradeep Chowdhury <quic_schowdhu@quicinc.com> > +Description: > + This file is used to read the KPI value abl time. > + It show the duration in milliseconds from the > + time control switched to ABL to the point when > + the linux kernel started getting loaded. > diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig > index a8f2830..0d2cbd3 100644 > --- a/drivers/soc/qcom/Kconfig > +++ b/drivers/soc/qcom/Kconfig > @@ -16,6 +16,15 @@ config QCOM_AOSS_QMP > subsystems as well as controlling the debug clocks exposed by the Always On > Subsystem (AOSS) using Qualcomm Messaging Protocol (QMP). > > +config QCOM_BOOTSTAT > + tristate "Qualcomm Technologies, Boot Stat driver" > + depends on ARCH_QCOM || COMPILE_TEST > + help > + This option enables driver support for boot stats. Boot stat driver logs > + the kernel bootloader information by accessing the imem region. These > + information are exposed in the form of debugfs files. This is used to > + determine if there is any regression in boot timings. > + > config QCOM_COMMAND_DB > tristate "Qualcomm Command DB" > depends on ARCH_QCOM || COMPILE_TEST > diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile > index 6e88da8..bdaa41a 100644 > --- a/drivers/soc/qcom/Makefile > +++ b/drivers/soc/qcom/Makefile > @@ -1,6 +1,7 @@ > # SPDX-License-Identifier: GPL-2.0 > CFLAGS_rpmh-rsc.o := -I$(src) > obj-$(CONFIG_QCOM_AOSS_QMP) += qcom_aoss.o > +obj-$(CONFIG_QCOM_BOOTSTAT) += boot_stats.o > obj-$(CONFIG_QCOM_GENI_SE) += qcom-geni-se.o > obj-$(CONFIG_QCOM_COMMAND_DB) += cmd-db.o > obj-$(CONFIG_QCOM_CPR) += cpr.o > diff --git a/drivers/soc/qcom/boot_stats.c b/drivers/soc/qcom/boot_stats.c > new file mode 100644 > index 0000000..7fa8efb > --- /dev/null > +++ b/drivers/soc/qcom/boot_stats.c > @@ -0,0 +1,101 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2013-2019, 2021 The Linux Foundation. All rights reserved. > + * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved. > + */ > + > +#include <linux/debugfs.h> > +#include <linux/err.h> > +#include <linux/io.h> > +#include <linux/init.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/platform_device.h> > + > +#define TO_MS(timestamp) ((timestamp * 1000) / 32768) Some of the platforms DTs define 32KHz clock instead of 32.768 KHz What should be the divisor in this case? > + > +/** > + * struct boot_stats - timestamp information related to boot stats > + * @abl_start: Time for the starting point of the abl > + * @abl_end: Time when the kernel starts loading from abl > + */ > +struct boot_stats { > + u32 abl_start; > + u32 abl_end; > +} __packed; > + > +struct bs_data { > + struct boot_stats __iomem *b_stats; > + struct dentry *dbg_dir; > +}; > + > +static int abl_time_show(struct seq_file *seq, void *v) > +{ > + struct boot_stats *boot_stats = seq->private; > + u32 abl_time = TO_MS(boot_stats->abl_end) - TO_MS(boot_stats->abl_start); > + > + seq_printf(seq, "%u ms\n", abl_time); > + return 0; > +} > +DEFINE_SHOW_ATTRIBUTE(abl_time); > + > +static int pre_abl_time_show(struct seq_file *seq, void *v) > +{ > + struct boot_stats *boot_stats = seq->private; > + > + seq_printf(seq, "%u ms\n", TO_MS(boot_stats->abl_start)); It would be better to move the unit to the file name and include just the number. > + return 0; > +} > +DEFINE_SHOW_ATTRIBUTE(pre_abl_time); > + > +static int boot_stats_probe(struct platform_device *pdev) > +{ > + struct device *bootstat_dev = &pdev->dev; > + struct bs_data *drvdata; > + > + drvdata = devm_kzalloc(bootstat_dev, sizeof(*drvdata), GFP_KERNEL); > + platform_set_drvdata(pdev, drvdata); > + > + drvdata->dbg_dir = debugfs_create_dir(dev_name(bootstat_dev), NULL); > + if (IS_ERR(drvdata->dbg_dir)) > + return dev_err_probe(bootstat_dev, -ENOENT, "failed to create debugfs directory"); > + > + drvdata->b_stats = devm_of_iomap(bootstat_dev, bootstat_dev->of_node, 0, NULL); > + if (!drvdata->b_stats) > + return dev_err_probe(bootstat_dev, -ENOMEM, "failed to map imem region\n"); > + > + debugfs_create_file("pre_abl_time", 0200, drvdata->dbg_dir, > + drvdata->b_stats, &pre_abl_time_fops); > + debugfs_create_file("abl_time", 0200, drvdata->dbg_dir, drvdata->b_stats, &abl_time_fops); > + > + return 0; > +} > + > +void boot_stats_remove(struct platform_device *pdev) > +{ > + struct bs_data *drvdata = platform_get_drvdata(pdev); > + > + debugfs_remove_recursive(drvdata->dbg_dir); > + iounmap(drvdata->b_stats); > +} > + > +static const struct of_device_id boot_stats_dt_match[] = { > + { .compatible = "qcom,sm8450-bootstats" }, Is it specific to sm8450 only? > + { } > +}; > +MODULE_DEVICE_TABLE(of, boot_stats_dt_match); > + > +static struct platform_driver boot_stat_driver = { > + .probe = boot_stats_probe, > + .remove_new = boot_stats_remove, > + .driver = { > + .name = "qcom-boot-stats", > + .of_match_table = boot_stats_dt_match, > + }, > +}; > +module_platform_driver(boot_stat_driver); > + > +MODULE_DESCRIPTION("Qualcomm Technologies Inc. Boot Stat driver"); > +MODULE_LICENSE("GPL");
On 04/05/2023 09:35, Souradeep Chowdhury wrote: > > > On 5/4/2023 4:23 AM, Caleb Connolly wrote: >> >> >> On 17/04/2023 16:08, Souradeep Chowdhury wrote: >>> All of Qualcomm's proprietary Android boot-loaders capture boot time >>> stats, like the time when the bootloader started execution and at what >>> point the bootloader handed over control to the kernel etc. in the IMEM >>> region. This information is captured in a specific format by this driver >>> by mapping a structure to the IMEM memory region and then accessing the >>> members of the structure to show the information within debugfs file. >>> This information is useful in verifying if the existing boot KPIs have >>> regressed or not. The information is shown in milliseconds, a sample >>> log from sm8450(waipio) device is as follows:- >>> >>> /sys/kernel/debug/146aa6b0.boot_stats # cat abl_time >>> 17898 ms >>> /sys/kernel/debug/146aa6b0.boot_stats # cat pre_abl_time >>> 2879 ms >>> >>> The Module Power Manager(MPM) sleep counter starts ticking at the PBL >>> stage and the timestamp generated by the sleep counter is logged by >>> the Qualcomm proprietary bootloader(ABL) at two points-> First when it >>> starts execution which is logged here as "pre_abl_time" and the second >>> when it is about to load the kernel logged as "abl_time". Documentation >>> details are also added in >>> Documentation/ABI/testing/debugfs-driver-bootstat >>> >>> Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com> >> >> Hi, >> >> [...] >>> + >>> +static int boot_stats_probe(struct platform_device *pdev) >>> +{ >>> + struct device *bootstat_dev = &pdev->dev; >>> + struct bs_data *drvdata; >>> + >>> + drvdata = devm_kzalloc(bootstat_dev, sizeof(*drvdata), GFP_KERNEL); >>> + platform_set_drvdata(pdev, drvdata); >>> + >>> + drvdata->dbg_dir = debugfs_create_dir(dev_name(bootstat_dev), >>> NULL); >> >> This might be better as just "qcom_boot_stats", rather than including >> the address. > > We usually use the dev_name to represent the one to one correspondence Who is "we"? > of the debugfs file with the device. Will create the root dir as > "qcom_boot_stats" and push the dev_name dir inside it. No, this doesn't sound logical. Please use just the "qcom_boot_stats" as Caleb suggested. > >> >> [...] >>> + >>> +static const struct of_device_id boot_stats_dt_match[] = { >>> + { .compatible = "qcom,sm8450-bootstats" }, >> >> This driver doesn't only support sm8450, I've tested this on sdm845 and >> it works just fine. Can we use a generic compatible here instead? > > We can add soc specific compatibles here to extend support for other > socs. This also captures the SoCs for which the driver is supported > which won't be the case if we use a generic compatible. No. If there is no difference between SoCs, please don't add soc-specific compatibles. They pollute the kernel and provide no additional benefits. Please use generic compatible and add platform-specific ones only if you have something to override. > > >>> + { } >>> +}; >>> +MODULE_DEVICE_TABLE(of, boot_stats_dt_match); >>> + >>> +static struct platform_driver boot_stat_driver = { >>> + .probe = boot_stats_probe, >>> + .remove_new = boot_stats_remove, >>> + .driver = { >>> + .name = "qcom-boot-stats", >>> + .of_match_table = boot_stats_dt_match, >>> + }, >>> +}; >>> +module_platform_driver(boot_stat_driver); >>> + >>> +MODULE_DESCRIPTION("Qualcomm Technologies Inc. Boot Stat driver"); >>> +MODULE_LICENSE("GPL"); >>> -- >>> 2.7.4 >>> >>
diff --git a/Documentation/ABI/testing/debugfs-driver-bootstat b/Documentation/ABI/testing/debugfs-driver-bootstat new file mode 100644 index 0000000..2543029 --- /dev/null +++ b/Documentation/ABI/testing/debugfs-driver-bootstat @@ -0,0 +1,17 @@ +What: /sys/kernel/debug/...stats/pre_abl_time +Date: April 2023 +Contact: Souradeep Chowdhury <quic_schowdhu@quicinc.com> +Description: + This file is used to read the KPI value pre abl time. + It shows the time in milliseconds from the starting + point of PBL to the point when the control shifted + to ABL(Qualcomm proprietary bootloader). + +What: /sys/kernel/debug/...stats/abl_time +Date: April 2023 +Contact: Souradeep Chowdhury <quic_schowdhu@quicinc.com> +Description: + This file is used to read the KPI value abl time. + It show the duration in milliseconds from the + time control switched to ABL to the point when + the linux kernel started getting loaded. diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig index a8f2830..0d2cbd3 100644 --- a/drivers/soc/qcom/Kconfig +++ b/drivers/soc/qcom/Kconfig @@ -16,6 +16,15 @@ config QCOM_AOSS_QMP subsystems as well as controlling the debug clocks exposed by the Always On Subsystem (AOSS) using Qualcomm Messaging Protocol (QMP). +config QCOM_BOOTSTAT + tristate "Qualcomm Technologies, Boot Stat driver" + depends on ARCH_QCOM || COMPILE_TEST + help + This option enables driver support for boot stats. Boot stat driver logs + the kernel bootloader information by accessing the imem region. These + information are exposed in the form of debugfs files. This is used to + determine if there is any regression in boot timings. + config QCOM_COMMAND_DB tristate "Qualcomm Command DB" depends on ARCH_QCOM || COMPILE_TEST diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile index 6e88da8..bdaa41a 100644 --- a/drivers/soc/qcom/Makefile +++ b/drivers/soc/qcom/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 CFLAGS_rpmh-rsc.o := -I$(src) obj-$(CONFIG_QCOM_AOSS_QMP) += qcom_aoss.o +obj-$(CONFIG_QCOM_BOOTSTAT) += boot_stats.o obj-$(CONFIG_QCOM_GENI_SE) += qcom-geni-se.o obj-$(CONFIG_QCOM_COMMAND_DB) += cmd-db.o obj-$(CONFIG_QCOM_CPR) += cpr.o diff --git a/drivers/soc/qcom/boot_stats.c b/drivers/soc/qcom/boot_stats.c new file mode 100644 index 0000000..7fa8efb --- /dev/null +++ b/drivers/soc/qcom/boot_stats.c @@ -0,0 +1,101 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2013-2019, 2021 The Linux Foundation. All rights reserved. + * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include <linux/debugfs.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> + +#define TO_MS(timestamp) ((timestamp * 1000) / 32768) + +/** + * struct boot_stats - timestamp information related to boot stats + * @abl_start: Time for the starting point of the abl + * @abl_end: Time when the kernel starts loading from abl + */ +struct boot_stats { + u32 abl_start; + u32 abl_end; +} __packed; + +struct bs_data { + struct boot_stats __iomem *b_stats; + struct dentry *dbg_dir; +}; + +static int abl_time_show(struct seq_file *seq, void *v) +{ + struct boot_stats *boot_stats = seq->private; + u32 abl_time = TO_MS(boot_stats->abl_end) - TO_MS(boot_stats->abl_start); + + seq_printf(seq, "%u ms\n", abl_time); + return 0; +} +DEFINE_SHOW_ATTRIBUTE(abl_time); + +static int pre_abl_time_show(struct seq_file *seq, void *v) +{ + struct boot_stats *boot_stats = seq->private; + + seq_printf(seq, "%u ms\n", TO_MS(boot_stats->abl_start)); + return 0; +} +DEFINE_SHOW_ATTRIBUTE(pre_abl_time); + +static int boot_stats_probe(struct platform_device *pdev) +{ + struct device *bootstat_dev = &pdev->dev; + struct bs_data *drvdata; + + drvdata = devm_kzalloc(bootstat_dev, sizeof(*drvdata), GFP_KERNEL); + platform_set_drvdata(pdev, drvdata); + + drvdata->dbg_dir = debugfs_create_dir(dev_name(bootstat_dev), NULL); + if (IS_ERR(drvdata->dbg_dir)) + return dev_err_probe(bootstat_dev, -ENOENT, "failed to create debugfs directory"); + + drvdata->b_stats = devm_of_iomap(bootstat_dev, bootstat_dev->of_node, 0, NULL); + if (!drvdata->b_stats) + return dev_err_probe(bootstat_dev, -ENOMEM, "failed to map imem region\n"); + + debugfs_create_file("pre_abl_time", 0200, drvdata->dbg_dir, + drvdata->b_stats, &pre_abl_time_fops); + debugfs_create_file("abl_time", 0200, drvdata->dbg_dir, drvdata->b_stats, &abl_time_fops); + + return 0; +} + +void boot_stats_remove(struct platform_device *pdev) +{ + struct bs_data *drvdata = platform_get_drvdata(pdev); + + debugfs_remove_recursive(drvdata->dbg_dir); + iounmap(drvdata->b_stats); +} + +static const struct of_device_id boot_stats_dt_match[] = { + { .compatible = "qcom,sm8450-bootstats" }, + { } +}; +MODULE_DEVICE_TABLE(of, boot_stats_dt_match); + +static struct platform_driver boot_stat_driver = { + .probe = boot_stats_probe, + .remove_new = boot_stats_remove, + .driver = { + .name = "qcom-boot-stats", + .of_match_table = boot_stats_dt_match, + }, +}; +module_platform_driver(boot_stat_driver); + +MODULE_DESCRIPTION("Qualcomm Technologies Inc. Boot Stat driver"); +MODULE_LICENSE("GPL");
All of Qualcomm's proprietary Android boot-loaders capture boot time stats, like the time when the bootloader started execution and at what point the bootloader handed over control to the kernel etc. in the IMEM region. This information is captured in a specific format by this driver by mapping a structure to the IMEM memory region and then accessing the members of the structure to show the information within debugfs file. This information is useful in verifying if the existing boot KPIs have regressed or not. The information is shown in milliseconds, a sample log from sm8450(waipio) device is as follows:- /sys/kernel/debug/146aa6b0.boot_stats # cat abl_time 17898 ms /sys/kernel/debug/146aa6b0.boot_stats # cat pre_abl_time 2879 ms The Module Power Manager(MPM) sleep counter starts ticking at the PBL stage and the timestamp generated by the sleep counter is logged by the Qualcomm proprietary bootloader(ABL) at two points-> First when it starts execution which is logged here as "pre_abl_time" and the second when it is about to load the kernel logged as "abl_time". Documentation details are also added in Documentation/ABI/testing/debugfs-driver-bootstat Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com> --- Documentation/ABI/testing/debugfs-driver-bootstat | 17 ++++ drivers/soc/qcom/Kconfig | 9 ++ drivers/soc/qcom/Makefile | 1 + drivers/soc/qcom/boot_stats.c | 101 ++++++++++++++++++++++ 4 files changed, 128 insertions(+) create mode 100644 Documentation/ABI/testing/debugfs-driver-bootstat create mode 100644 drivers/soc/qcom/boot_stats.c