Debug with sysfs or debugfs nodes - Qualcomm Dragonwing Documentation

To identify the status or update the state, use the sysfs and debugfs nodes. Mount debugfs to ensure that the debugfs file system is accessible for the debug nodes.

mount -t debugfs none /sys/kernel/debug

UFS device state commands

Required UFS device state information	Command
Check PA/DL error count	`cat /sys/kernel/debug/ufshcd/1d84000.ufshc/stats`
Read UFS device gating delay, in ms	`cat /sys/devices/platform/soc@0/1d84000.ufshc/clkgate_delay_ms`
Read UFS device clocks current frequency at given point	`cat /sys/devices/platform/soc@0/1d84000.ufshc/devfreq/1d84000.ufshc/cur_freq`
Read UFS device I/O scheduler details	`cat /sys/devices/platform/soc@0/1d84000.ufshc/devfreq/1d84000.ufshc/governor`
Read UFS device min frequency during clock scale down	`cat /sys/devices/platform/soc@0/1d84000.ufshc/devfreq/1d84000.ufshc/min_freq`
Read UFS device max frequency during clock scale up	`cat /sys/devices/platform/soc@0/1d84000.ufshc/devfreq/1d84000.ufshc/max_freq`
Read UFS device state active or sleep	`cat /sys/devices/platform/soc@0/1d84000.ufshc/power_info/dev_pm`
Read UFS device gear information such as HS_GEAR3, HS_GEAR4	`cat /sys/devices/platform/soc@0/1d84000.ufshc/power_info/gear`
Read UFS device number of lanes	`cat /sys/devices/platform/soc@0/1d84000.ufshc/power_info/lane`
Read UFS device link state, ACTIVE or HIBERN8	`cat /sys/devices/platform/soc@0/1d84000.ufshc/power_info/link_state`
Read UFS device rate information such as Rate A or B	`cat /sys/devices/platform/soc@0/1d84000.ufshc/power_info/rate`
Read UFS device descriptor information	`ls /sys/devices/platform/soc@0/1d84000.ufshc/device_descriptor`
Read UFS device health descriptor information	`ls /sys/devices/platform/soc@0/1d84000.ufshc/health_descriptor`
Read UFS device runtime status information active or suspended	`cat /sys/devices/platform/soc@0/1d84000.ufshc/power/runtime_status`
Find and/or modify the SPM/RPM level	`cat /sys/devices/platform/soc@0/1d84000.ufshc/rpm_lvl` `cat /sys/devices/platform/soc@0/1d84000.ufshc/spm_lvl`

SD card state commands

Before running the SD card state commands, identify the MMC host controller instance# and its physical address.

Enumerate MMC Host Controllers.
ls -l /sys/class/mmc_host
Identify the MMC physical address.
readlink -f /sys/class/mmc_host/mmc*

Required SD card state information	Command
Read SD card error stats information	`cat /sys/kernel/debug/mmc1/err_stats`
Read SD card latest error state details	`cat /sys/kernel/debug/mmc1/err_state`
Check the current running clock details	`cat /sys/kernel/debug/mmc1/clock`
Read the SD card runtime status information (active or suspended)	`cat /sys/devices/platform/soc@0/<mmc_addr>.mmc/power/runtime_status`
Read SD card auto suspend delay time	`cat /sys/devices/platform/soc@0/<mmc_addr>.mmc/power/autosuspend_delay_ms`
Read SD card runtime active time	`cat /sys/devices/platform/soc@0/<mmc_addr>.mmc/power/runtime_active_time`
Read SD card runtime suspend time	`cat /sys/devices/platform/soc@0/<mmc_addr>.mmc/power/runtime_suspended_time`
Read SD card uevent details	`cat /sys/devices/platform/soc@0/<mmc_addr>.mmc/uevent`

NVMe state commands

Required NVMe card state information	Command
View device model name	`cat /sys/class/nvme/nvme0/model`
View device serial number	`cat /sys/class/nvme/nvme0/serial`
View current firmware version	`cat /sys/class/nvme/nvme0/firmware_rev`
View namespace identifier	`cat /sys/class/nvme/nvme0/nvme0n1/nsid`
View namespace size	`cat /sys/class/nvme/nvme0/nvme0n1/size`
View the offset in bytes to align the start of the NVMe namespace to the optimal I/O boundary	`cat /sys/class/nvme/nvme0/nvme0n1/alignment_offset`
View queue depth	`cat /sys/class/nvme/nvme0/queue_count`

eMMC node commands

Description	Command
eMMC error stats information	`cat /sys/kernel/debug/mmc0/err_stats`
eMMC latest error state details	`cat /sys/kernel/debug/mmc0/err_state`
Current running clock details of an eMMC	`cat /sys/kernel/debug/mmc0/clock`
eMMC runtime status information	`cat /sys/devices/platform/soc@0/<sdhci_addr>.mmc/power/runtime_status`
eMMC auto suspend delay time	`cat /sys/devices/platform/soc@0/<sdhci_addr>.mmc/power/autosuspend_delay_ms`
eMMC runtime active time	`cat /sys/devices/platform/soc@0/<sdhci_addr>.mmc/power/runtime_active_time`
eMMC runtime suspend time	`cat /sys/devices/platform/soc@0/<sdhci_addr>.mmc/power/runtime_suspended_time`
eMMC uevent details	`cat /sys/devices/platform/soc@0/<sdhci_addr>.mmc/uevent`

Update the <sdhci_address> values based on the SDHCI physical address of the chip products.Example:

Qualcomm Dragonwing™ IQ-615: 7c4000
Qualcomm Dragonwing™ IQ-8275: 87c4000
Qualcomm Dragonwing™ IQ-9075: 7c4000

​UFS device state commands

​SD card state commands

​NVMe state commands

​eMMC node commands

UFS device state commands

SD card state commands

NVMe state commands

eMMC node commands