VideoCore Tools
As I work with Qt 5 on the Raspberry Pi, I frequently have a need for getting information about what impact I am having on the GPU. The tools available to get this information however are not well documented, and any information about them is spread about in various forums and wikis. So in an effort to dump the information that I've found so far here goes:
V3D_GL_ERROR_ASSIST=1
V3D_DOUBLE_BUFFER=1
By default VideoCore is set up to have a triple buffered framebuffer, setting this variable forces double buffering
V3D_NO_BIN_RENDER_OVERLAP=1
V3D_REG_DUMP_ON_LOCK=1
V3D_CLIF_DUMP_ON_LOCK=1
V3D_FORCE_DITHER_OFF=1
V3D_BIN_BLOCK_SIZE=(int)
V3D_MAX_BIN_BLOCKS=(int)
Tools are provided in: /opt/vc/bin
vcdbg dump addr len
Dumps memory (Hex and ASCII)
vcdbg help [command]
Prints command help information
vcdbg hist
Generates gnuplot task history files.
vcdbg log command [args]
Commands related to logging
vcdbg malloc
Report on the VC malloc heap
vcdbg pools [name]
Report on vc_pools
vcdbg reloc [small|stats]
Dump out relocatable heap [or just small, or stats]
vcdbg save filename [addr len]
Saves the indicated memory (or all) to a file
vcdbg sym symbol
Prints out the values of the indicated symbol
vcdbg syms
Prints out the values of the available symbols
vcdbg trash addr [len]
Trash VC memory (Hex and ASCII) [default: 1 byte]
vcdbg reloc | awk -F '[ ,]*' '/^\[/ {sum += $12} END { print sum }'
prints the size of all allocated buffers in bytes
vcdbg log assert
check VideoCore log for any recent asserts
vcdbg log msg
check VideoCore log
vcgencmd vcos command
Possible commands are log, help, and version
vcgencmd vcos log assert
Does a vcos_assert(0) to test logging
vcgencmd vcos log set category level
Sets the vcos logging level for a category
vcgencmd vcos log status [category]
Prints the vcos log status for a (or all) categories
vcgencmd vcos log test [arbitrary text]
Does a vcos_log to test logging
vcgencmd ap_output_control
vcgencmd ap_output_post_processing
vcgencmd pm_set_policy
vcgencmd pm_get_status
vcgencmd pm_show_stats
vcgencmd pm_start_logging
vcgencmd pm_stop_logging
vcgencmd set_vll_dir
vcgencmd led_control
vcgencmd set_backlight
Predates the Pi and is used for controlling the backlight on LCD displays.
It's not plumbed in to anything on Pi (although could be in the future).
vcgencmd get_lcd_info
Returns height, width, and depth of the display framebuffer
vcgencmd set_bus_arbiter_mode
vcgencmd otp_dump
vcgencmd codec_enabled
Shows if the specified codec is enabled, codec can be one of H264 MPG2 WVC1
vcgencmd measure_clock
Shows clock frequency, clock can be one of arm, core, h264, isp, v3d, uart, pwm, emmc, pixel, vec, hdmi, dpi
vcgencmd measure_volts
Shows voltage, id can be one core, sdram_c, sdram_i, sdram_p, and defaults to core if not specified.
vcgencmd measure_temp
Shows core temperature of BCM2835 SoC.
vcgencmd get_config
vcgencmd hdmi_ntsc_freqs
vcgencmd render_bar
Created for debug purposes, see omxplayer.cpp. Needs 'enable_hdmi_status=1' in config.txt
vcgencmd disk_notify
vcgencmd inuse_notify
vcgencmd sus_suspend
vcgencmd sus_status
vcgencmd sus_is_enabled
vcgencmd sus_stop_test_thread
vcgencmd egl_platform_switch
vcgencmd mem_validate
vcgencmd mem_oom
Reports statistics on Out of Memory events
vcgencmd mem_reloc_stats
Reports statics on relocatable memory
vcgencmd file
vcgencmd vctest_memmap
vcgencmd vctest_start
vcgencmd vctest_stop
vcgencmd vctest_set
vcgencmd vctest_get
vcgencmd cache_flush
flush GPU's L1 cache
vcgencmd version
print current build version of VideoCore firmware
vcgencmd set_logging level=64
Change the verbosity of the VideoCore logger. The following table lists the possible values for level (which can be combined)
| Log Level | Description | Value |
|---|---|---|
| LOGGING_GENERAL | for logging general messages | 1 |
| LOGGING_GENERAL_VERBOSE | 2 | |
| LOGGING_CODECS | for codec messages | 4 |
| LOGGING_CODECS_VERBOSE | 8 | |
| LOGGING_FILESYSTEM | filesystem messages | 16 |
| LOGGING_FILESYSTEM_VERBOSE | 32 | |
| LOGGING_VMCS | VMCS related messages | 64 |
| LOGGING_VMCS_VERBOSE | 128 | |
| LOGGING_DISPMAN2 | Dispman2/scalar logs | 256 |
| LOGGING_DISPMAN2_VERBOSE | 512 | |
| LOGGING_GCE | Re-use Dispman2 for GCE logging | 256 |
| LOGGING_GCE_VERBOSE | 512 | |
| LOGGING_CAMPLUS | Camplus logs | 1024 |
| LOGGING_CAMPLUS_VERBOSE | 2048 | |
| LOGGING_APPS | Application log | 4096 |
| LOGGING_APPS_VERBOSE | 8192 | |
| LOGGING_CLOCKMAN_POWERMAN | Clockman + powerman logs | 16384 |
| LOGGING_CLOCKMAN_POWERMAN_VERBOSE | 32768 | |
| LOGGING_VCOS | 65536 | |
| LOGGING_VCOS_VERBOSE | 131072 | |
| LOGGING_IMAGE_POOL | Image pool messages | 262144 |
| LOGGING_IMAGE_POOL_VERBOSE | 524288 | |
| LOGGING_HDMI | HDMI and HDCP messages | 1048576 |
| LOGGING_HDMI_VERBOSE | 2097152 | |
| LOGGING_MINIMAL | minimal logging for bandwidth measurement, ie all others off | 4194304 |
| LOGGING_MINIMAL_VERBOSE | 8388608 | |
| LOGGING_TUNER | ISP Tuner logs - AGC, AWB etc | 16777216 |
| LOGGING_TUNER_VERBOSE | 33554432 | |
| LOGGING_VCHI | For all VCHI based services | 67108864 |
| LOGGING_VCHI_VERBOSE | 134217728 | |
| LOGGING_FOCUS | Focus messages | 268435456 |
| LOGGING_HANDLERS | For handler messages | 536870912 |
| LOGGING_VOWIFI | Re-use FOCUS for VOWIFI | 268435456 |
| LOGGING_VOWIFI_VERBOSE | Re-use HANDLERS for VOWIFI | 536870912 |
| LOGGING_USER | only for code under development - do not check in! | 1073741824 |
| LOGGING_USER_VERBOSE | 2147483648 |