This driver relies on SMEM to populate items for each subsystem before
the device probes. The items in SMEM that are being looked for are
populated by the subsystems lazily, and therefore may not exist until
the device has booted. For example, if I build this driver into the
kernel on Trogdor Lazor and boot up, I don't see a 'modem' debugfs file
populated, because the modem boots and populates the SMEM item after
this driver probes.
Always populate the files for the subsystems if they're in SMEM, and
make the qcom_subsystem_sleep_stats_show() function return 0 if the SMEM
items still isn't there. This way we can run a simple command like
grep ^ /sys/kernel/debug/qcom_stats/*
and collect the subsystem sleep stats without interspersed errors or
missing details entirely because this driver probed first.
Fixes: 1d77246903 ("soc: qcom: Add Sleep stats driver")
Cc: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230119032329.2909383-1-swboyd@chromium.org
Not all RPM firmware versions have the dynamic sleep stats offset
available. Most older versions use a fixed offset of 0xdba0.
Add support for this using new SoC-specific compatibles for APQ8084,
MSM8226, MSM8916 and MSM8974.
Even older SoCs seem to use a different offset and stats format.
If needed those could be supported in the future by adding separate
compatibles for those with a different stats_config.
Cc: Maulik Shah <mkshah@codeaurora.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20211119213953.31970-3-stephan@gerhold.net
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>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/1634107104-22197-3-git-send-email-mkshah@codeaurora.org
