n900-pm

#!/sbin/openrc-run
#
# Start-up script to configure n900 for power management
#
# The LCD needs to be blanked with xset -display :0 dpms force off and
# unblanked with xset -display :0 dpms force on to idle DSS clocks.
#
# Please disable known problem modules for now by adding them into
# /etc/modprobe.d/blacklist.conf:
#
# blacklist ehci-omap
# blacklist hci_uart
# blacklist omap_hdq
#
# To monitor power consumption, check the power consumption by reading
# the micro-Watts with cat:
#
# /sys/class/power_supply/bq27200-0/power_avg
#
# To check no device drivers or busy timers are blocking SoC idle states,
# check that the RET count keeps increasing when doing:
#
# grep ^core_pwrdm /sys/kernel/debug/pm_debug/count
#
# This script can also log the power usage status if run with n900 status.
# You can add it to root crontab to log power consumption once a minute:
#
# * * * * * /etc/init.d/n900-pm status >> /var/log/n900-pm 2>&1
#
# And the recent power consumption history can be monitored with:
#
# tail /var/log/n900-pm
#  * d=2020-02-19|t=16:40:00|i=OFF:0,RET:27562|p=61|b=none
#  * d=2020-02-19|t=16:41:00|i=OFF:0,RET:27962|p=60|b=none
#  * d=2020-02-19|t=16:42:00|i=OFF:0,RET:28302|p=58|b=none
# ...
#

name="n900-pm"


UART_IDLE_MS=3000

devmem=""
rwmem=""
blockers=""

depend() {
	if grep -i -e alpine /etc/os-release > /dev/null 2>&1; then
	        need dev
	        after hwdrivers
	elif grep -i -e devuan /etc/os-release > /dev/null 2>&1; then
	        need eudev
	        after kmod
	fi
}

warn_if_module_loaded() {
	module="${1}"
	desc="${2}"

	if lsmod | grep "${module}" > /dev/null; then
	        ewarn "Module ${module} blocks idle: ${desc}"
	fi
}

check_module_blacklist() {
	einfo "Checking for blacklisted modules blocking idle"
	warn_if_module_loaded ehci-omap "Blocks idle, blacklist?"
	warn_if_module_loaded omap_hdq "Seems to poll devices, blacklist?"
	warn_if_module_loaded hci_uart "Blocks uart4 idle oopses on rmmod, blacklist?"
	#warn_if_module_loaded atmel_mxt_ts "Should be unloaded when screen is blanked"
}

set_loglevel() {
	loglevel="${1}"

	einfo "Setting kernel loglevel to ${loglevel}"
	echo "${loglevel}" > /proc/sysrq-trigger
}

idle_uarts() {
	einfo "Idling UARTs"

	# Detach kernel serial console
	consoles=$(find /sys/bus/platform/devices/4*.serial/ -name console)
	for console in ${consoles}; do
	        echo N > ${console}
	done

	# Enable autosuspend
	uarts=$(find /sys/bus/platform/devices/4*.serial/power/ -type d)
	for uart in ${uarts}; do
	        echo ${UART_IDLE_MS} > ${uart}/autosuspend_delay_ms
	        echo enabled > ${uart}/wakeup
	        echo auto > ${uart}/control
	done

	# Configure wake-up from suspend
	uarts=$(find /sys/class/tty/tty[SO]*/power/ -type d)
	for uart in ${uarts}; do
	        echo enabled > ${uart}/wakeup
	done
}

enable_soc_idle_states() {
	einfo "Enabling deeper SoC idle states"
	echo 1 > /sys/kernel/debug/pm_debug/enable_off_mode
}

init_reg_read() {
	if busybox devmem > /dev/null 2>&1; then
	        devmem="busybox devmem"
	        return
	fi

	rwmem=$(which rwmem)
}

check_clkctrl() {
	address="${1}"
	idleval="${2}"
	desc="${3}"

	if [ "${devmem}" != "" ]; then
	        val=$("${devmem}" "${address}")
	elif [ "${rwmem}" != "" ]; then
	        val=$("${rwmem}" "${address}" | cut -d' ' -f3)
	else
	        return
	fi

	if [ "${val}" != "${idleval}" ]; then
	        echo -n "${desc}"
	fi
}

update_blockers() {
	address="${1}"
	idleval="${2}"
	desc="${3}"

	device=$(check_clkctrl "${address}" "${idleval}" "${desc}")

	if [ "${blockers}" = "" ] && [ "${device}" != "" ]; then
	        blockers="${device}"
	elif [ "${device}" != "" ]; then
	        blockers="${blockers},${device}"
	fi
}

check_status() {
	blocker_bits=$(cat /sys/kernel/debug/pm_debug/count | grep idlest1 | awk '{print $7}')
	idle=$(grep ^core_pwrdm /sys/kernel/debug/pm_debug/count | cut -d',' -f2,3)
	uw=$(cat /sys/class/power_supply/bq27200-0/power_avg)
	mw=$((${uw} / 1000))
	cap=$(cat /sys/class/power_supply/bq27200-0/capacity)
	if [ "${reg_read_cmd}" = "" ]; then
	        init_reg_read
	fi

	blockers=`python3 - $blocker_bits << EOF
import sys

# 31 to 0
cm_idlest1_core_bits = [ 'RESERVED', 'ST_MMC3', 'ST_ICR',
'RESERVED', 'RESERVED', 'RESERVED', 'ST_MMC2', 'ST_MMC1',
'RESERVED', 'ST_HDQ', 'ST_MCSPI4', 'ST_MCSPI3', 'ST_MCSPI2',
'ST_MCSPI1', 'ST_I2C3', 'ST_I2C2', 'ST_I2C1', 'ST_UART2',
'ST_UART1', 'ST_GPT11', 'ST_GPT10', 'ST_MCBSP5', 'ST_MCBSP1',
'RESERVED', 'ST_MAILBOXES', 'ST_OMAPCTRL', 'ST_HSOTGUSB_IDLE',
'ST_HSOTGUSB_STDBY', 'RESERVED', 'ST_SDMA', 'ST_SDRC', 'RESERVED',
]

cm_idlest1_core_bits = list(reversed(cm_idlest1_core_bits))
inp = sys.argv[1]
v = int(inp, 16)
b= '{0:b}'.format(v)
blockers = []
for i in range(0, 32):
    is_set = (v & (1 << i)) >> i
    if is_set:
        blockers.append(cm_idlest1_core_bits[i])
print(','.join(blockers),end='')
EOF`

	if [ "${blockers}" = "" ]; then
	        blockers="none"
	fi

	date=$(date +%Y-%m-%d)
	time=$(date +%H:%M:%S)

	echo "d=${date}|t=${time}|i=${idle}|p=${mw}|c=${cap}|b=${blockers}"
}

start() {
	check_module_blacklist
	idle_uarts
	set_loglevel 0
	enable_soc_idle_states
}

status() {
	check_status
}