Environment Variables

Normally, no environment variables need to be set. Most of the environment variables used by Mesa/Gallium are for debugging purposes, but they can sometimes be useful for debugging end-user issues.

LibGL environment variables

LIBGL_DEBUG

If defined debug information will be printed to stderr. If set to verbose additional information will be printed.

LIBGL_DRIVERS_PATH

colon-separated list of paths to search for DRI drivers

LIBGL_ALWAYS_INDIRECT

if set to true, forces an indirect rendering context/connection.

LIBGL_ALWAYS_SOFTWARE

if set to true, always use software rendering

LIBGL_NO_DRAWARRAYS

if set to true, do not use DrawArrays GLX protocol (for debugging)

LIBGL_SHOW_FPS

print framerate to stdout based on the number of glXSwapBuffers calls per second.

LIBGL_DRI2_DISABLE

disable DRI2 if set to true.

LIBGL_DRI3_DISABLE

disable DRI3 if set to true.

Core Mesa environment variables

MESA_NO_ASM

if set, disables all assembly language optimizations

MESA_NO_MMX

if set, disables Intel MMX optimizations

MESA_NO_3DNOW

if set, disables AMD 3DNow! optimizations

MESA_NO_SSE

if set, disables Intel SSE optimizations

MESA_NO_ERROR

if set to 1, error checking is disabled as per KHR_no_error. This will result in undefined behavior for invalid use of the API, but can reduce CPU use for apps that are known to be error free.

MESA_DEBUG

if set, error messages are printed to stderr. For example, if the application generates a GL_INVALID_ENUM error, a corresponding error message indicating where the error occurred, and possibly why, will be printed to stderr. For release builds, MESA_DEBUG defaults to off (no debug output). MESA_DEBUG accepts the following comma-separated list of named flags, which adds extra behavior to just set MESA_DEBUG to 1:

silent

turn off debug messages. Only useful for debug builds.

flush

flush after each drawing command

incomplete_tex

extra debug messages when a texture is incomplete

incomplete_fbo

extra debug messages when a FBO is incomplete

context

create a debug context (see GLX_CONTEXT_DEBUG_BIT_ARB) and print error and performance messages to stderr (or MESA_LOG_FILE).

MESA_LOG_FILE

specifies a file name for logging all errors, warnings, etc., rather than stderr

MESA_EXTENSION_OVERRIDE

can be used to enable/disable extensions. A value such as GL_EXT_foo -GL_EXT_bar will enable the GL_EXT_foo extension and disable the GL_EXT_bar extension. Note that this will override extensions override configured using driconf.

MESA_EXTENSION_MAX_YEAR

The GL_EXTENSIONS string returned by Mesa is sorted by extension year. If this variable is set to year X, only extensions defined on or before year X will be reported. This is to work-around a bug in some games where the extension string is copied into a fixed-size buffer without truncating. If the extension string is too long, the buffer overrun can cause the game to crash. This is a work-around for that.

MESA_GL_VERSION_OVERRIDE

changes the value returned by glGetString(GL_VERSION) and possibly the GL API type.

  • The format should be MAJOR.MINOR[FC|COMPAT]

  • FC is an optional suffix that indicates a forward compatible context. This is only valid for versions >= 3.0.

  • COMPAT is an optional suffix that indicates a compatibility context or GL_ARB_compatibility support. This is only valid for versions >= 3.1.

  • GL versions <= 3.0 are set to a compatibility (non-Core) profile

  • GL versions = 3.1, depending on the driver, it may or may not have the ARB_compatibility extension enabled.

  • GL versions >= 3.2 are set to a Core profile

  • Examples:

    2.1

    select a compatibility (non-Core) profile with GL version 2.1.

    3.0

    select a compatibility (non-Core) profile with GL version 3.0.

    3.0FC

    select a Core+Forward Compatible profile with GL version 3.0.

    3.1

    select GL version 3.1 with GL_ARB_compatibility enabled per the driver default.

    3.1FC

    select GL version 3.1 with forward compatibility and GL_ARB_compatibility disabled.

    3.1COMPAT

    select GL version 3.1 with GL_ARB_compatibility enabled.

    X.Y

    override GL version to X.Y without changing the profile.

    X.YFC

    select a Core+Forward Compatible profile with GL version X.Y.

    X.YCOMPAT

    select a Compatibility profile with GL version X.Y.

  • Mesa may not really implement all the features of the given version. (for developers only)

MESA_GLES_VERSION_OVERRIDE

changes the value returned by glGetString(GL_VERSION) for OpenGL ES.

  • The format should be MAJOR.MINOR

  • Examples: 2.0, 3.0, 3.1

  • Mesa may not really implement all the features of the given version. (for developers only)

MESA_GLSL_VERSION_OVERRIDE

changes the value returned by glGetString(GL_SHADING_LANGUAGE_VERSION). Valid values are integers, such as 130. Mesa will not really implement all the features of the given language version if it’s higher than what’s normally reported. (for developers only)

MESA_GLSL_CACHE_DISABLE

if set to true, disables the GLSL shader cache. If set to false, enables the GLSL shader cache when it is disabled by default.

MESA_GLSL_CACHE_MAX_SIZE

if set, determines the maximum size of the on-disk cache of compiled GLSL programs. Should be set to a number optionally followed by K, M, or G to specify a size in kilobytes, megabytes, or gigabytes. By default, gigabytes will be assumed. And if unset, a maximum size of 1GB will be used.

Note

A separate cache might be created for each architecture that Mesa is installed for on your system. For example under the default settings you may end up with a 1GB cache for x86_64 and another 1GB cache for i386.

MESA_GLSL_CACHE_DIR

if set, determines the directory to be used for the on-disk cache of compiled GLSL programs. If this variable is not set, then the cache will be stored in $XDG_CACHE_HOME/mesa_shader_cache (if that variable is set), or else within .cache/mesa_shader_cache within the user’s home directory.

MESA_GLSL

shading language compiler options

MESA_NO_MINMAX_CACHE

when set, the minmax index cache is globally disabled.

MESA_SHADER_CAPTURE_PATH

see Capturing Shaders

MESA_SHADER_DUMP_PATH and MESA_SHADER_READ_PATH

see Experimenting with Shader Replacements

MESA_VK_VERSION_OVERRIDE

changes the Vulkan physical device version as returned in VkPhysicalDeviceProperties::apiVersion.

  • The format should be MAJOR.MINOR[.PATCH]

  • This will not let you force a version higher than the driver’s instance version as advertised by vkEnumerateInstanceVersion

  • This can be very useful for debugging but some features may not be implemented correctly. (For developers only)

MESA_VK_WSI_PRESENT_MODE

overrides the WSI present mode clients specify in VkSwapchainCreateInfoKHR::presentMode. Values can be fifo, relaxed, mailbox or immediate.

MESA_VK_ABORT_ON_DEVICE_LOSS

causes the Vulkan driver to call abort() immediately after detecting a lost device. This is extremely useful when testing as it prevents the test suite from continuing on with a lost device.

MESA_VK_ENABLE_SUBMIT_THREAD

for Vulkan drivers which support real timeline semaphores, this forces them to use a submit thread from the beginning, regardless of whether or not they ever see a wait-before-signal condition.

MESA_LOADER_DRIVER_OVERRIDE

chooses a different driver binary such as etnaviv or zink.

NIR passes environment variables

The following are only applicable for drivers that uses NIR, as they modify the behavior for the common NIR_PASS and NIR_PASS_V macros, that wrap calls to NIR lowering/optimizations.

NIR_DEBUG

a comma-separated list of debug options to apply to NIR shaders. Use NIR_DEBUG=help to print a list of available options.

NIR_SKIP

a comma-separated list of optimization/lowering passes to skip.

Mesa Xlib driver environment variables

The following are only applicable to the Mesa Xlib software driver. See the Xlib software driver page for details.

MESA_RGB_VISUAL

specifies the X visual and depth for RGB mode

MESA_BACK_BUFFER

specifies how to implement the back color buffer, either pixmap or ximage

MESA_XSYNC

enable synchronous X behavior (for debugging only)

MESA_GLX_FORCE_ALPHA

if set, forces RGB windows to have an alpha channel.

MESA_GLX_DEPTH_BITS

specifies default number of bits for depth buffer.

MESA_GLX_ALPHA_BITS

specifies default number of bits for alpha channel.

Intel driver environment variables

INTEL_BLACKHOLE_DEFAULT

if set to 1, true or yes, then the OpenGL implementation will default GL_BLACKHOLE_RENDER_INTEL to true, thus disabling any rendering.

INTEL_DEBUG

a comma-separated list of named flags, which do various things:

ann

annotate IR in assembly dumps

aub

dump batches into an AUB trace for use with simulation tools

bat

emit batch information

blit

emit messages about blit operations

blorp

emit messages about the blorp operations (blits & clears)

buf

emit messages about buffer objects

clip

emit messages about the clip unit (for old gens, includes the CLIP program)

color

use color in output

cs

dump shader assembly for compute shaders

do32

generate compute shader SIMD32 programs even if workgroup size doesn’t exceed the SIMD16 limit

fs

dump shader assembly for fragment shaders

gs

dump shader assembly for geometry shaders

hex

print instruction hex dump with the disassembly

l3

emit messages about the new L3 state during transitions

no8

don’t generate SIMD8 fragment shader

no16

suppress generation of 16-wide fragment shaders. useful for debugging broken shaders

nocompact

disable instruction compaction

nodualobj

suppress generation of dual-object geometry shader code

nofc

disable fast clears

norbc

disable single sampled render buffer compression

optimizer

dump shader assembly to files at each optimization pass and iteration that make progress

perf

emit messages about performance issues

perfmon

emit messages about AMD_performance_monitor

reemit

mark all state dirty on each draw call

sf

emit messages about the strips & fans unit (for old gens, includes the SF program)

shader_time

record how much GPU time is spent in each shader

spill_fs

force spilling of all registers in the scalar backend (useful to debug spilling code)

spill_vec4

force spilling of all registers in the vec4 backend (useful to debug spilling code)

submit

emit batchbuffer usage statistics

sync

after sending each batch, emit a message and wait for that batch to finish rendering

tcs

dump shader assembly for tessellation control shaders

tes

dump shader assembly for tessellation evaluation shaders

tex

emit messages about textures.

urb

emit messages about URB setup

vs

dump shader assembly for vertex shaders

INTEL_MEASURE

Collects GPU timestamps over common intervals, and generates a CSV report to show how long rendering took. The overhead of collection is limited to the flushing that is required at the interval boundaries for accurate timestamps. By default, timing data is sent to stderr. To direct output to a file:

INTEL_MEASURE=file=/tmp/measure.csv {workload}

To begin capturing timestamps at a particular frame:

INTEL_MEASURE=file=/tmp/measure.csv,start=15 {workload}

To capture only 23 frames:

INTEL_MEASURE=count=23 {workload}

To capture frames 15-37, stopping before frame 38:

INTEL_MEASURE=start=15,count=23 {workload}

Designate an asynchronous control file with:

INTEL_MEASURE=control=path/to/control.fifo {workload}

As the workload runs, enable capture for 5 frames with:

$ echo 5 > path/to/control.fifo

Enable unbounded capture:

$ echo -1 > path/to/control.fifo

and disable with:

$ echo 0 > path/to/control.fifo

Select the boundaries of each snapshot with:

INTEL_MEASURE=draw

Collects timings for every render (DEFAULT)

INTEL_MEASURE=rt

Collects timings when the render target changes

INTEL_MEASURE=batch

Collects timings when batches are submitted

INTEL_MEASURE=frame

Collects timings at frame boundaries

With INTEL_MEASURE=interval=5, the duration of 5 events will be combined into a single record in the output. When possible, a single start and end event will be submitted to the GPU to minimize stalling. Combined events will not span batches, except in the case of INTEL_MEASURE=frame.

INTEL_NO_HW

if set to 1, true or yes, prevents batches from being submitted to the hardware. This is useful for debugging hangs, etc.

INTEL_PRECISE_TRIG

if set to 1, true or yes, then the driver prefers accuracy over performance in trig functions.

INTEL_SHADER_ASM_READ_PATH

if set, determines the directory to be used for overriding shader assembly. The binaries with custom assembly should be placed in this folder and have a name formatted as sha1_of_assembly.bin. The sha1 of a shader assembly is printed when assembly is dumped via corresponding INTEL_DEBUG flag (e.g. vs for vertex shader). A binary could be generated from a dumped assembly by i965_asm. For INTEL_SHADER_ASM_READ_PATH to work it is necessary to enable dumping of corresponding shader stages via INTEL_DEBUG. It is advised to use nocompact flag of INTEL_DEBUG when dumping and overriding shader assemblies. The success of assembly override would be signified by “Successfully overrode shader with sha1 <sha1>” in stderr replacing the original assembly.

DRI environment variables

DRI_NO_MSAA

disable MSAA for GLX/EGL MSAA visuals

EGL environment variables

Mesa EGL supports different sets of environment variables. See the Mesa EGL page for the details.

Gallium environment variables

GALLIUM_HUD

draws various information on the screen, like framerate, CPU load, driver statistics, performance counters, etc. Set GALLIUM_HUD to help and run e.g. glxgears for more info.

GALLIUM_HUD_PERIOD

sets the HUD update rate in seconds (float). Use zero to update every frame. The default period is 1/2 second.

GALLIUM_HUD_VISIBLE

control default visibility, defaults to true.

GALLIUM_HUD_TOGGLE_SIGNAL

toggle visibility via user specified signal. Especially useful to toggle HUD at specific points of application and disable for unencumbered viewing the rest of the time. For example, set GALLIUM_HUD_VISIBLE to false and GALLIUM_HUD_TOGGLE_SIGNAL to 10 (SIGUSR1). Use kill -10 <pid> to toggle the HUD as desired.

GALLIUM_HUD_SCALE

Scale HUD by an integer factor, for high DPI displays. Default is 1.

GALLIUM_HUD_DUMP_DIR

specifies a directory for writing the displayed HUD values into files.

GALLIUM_DRIVER

useful in combination with LIBGL_ALWAYS_SOFTWARE`=`true for choosing one of the software renderers softpipe or llvmpipe.

GALLIUM_LOG_FILE

specifies a file for logging all errors, warnings, etc. rather than stderr.

GALLIUM_PIPE_SEARCH_DIR

specifies an alternate search directory for pipe-loader which overrides the compile-time path based on the install location.

GALLIUM_PRINT_OPTIONS

if non-zero, print all the Gallium environment variables which are used, and their current values.

GALLIUM_DUMP_CPU

if non-zero, print information about the CPU on start-up

TGSI_PRINT_SANITY

if set, do extra sanity checking on TGSI shaders and print any errors to stderr.

DRAW_FSE

Enable fetch-shade-emit middle-end even though its not correct (e.g. for softpipe)

DRAW_NO_FSE

Disable fetch-shade-emit middle-end even when it is correct

DRAW_USE_LLVM

if set to zero, the draw module will not use LLVM to execute shaders, vertex fetch, etc.

ST_DEBUG

controls debug output from the Mesa/Gallium state tracker. Setting to tgsi, for example, will print all the TGSI shaders. See src/mesa/state_tracker/st_debug.c for other options.

Clover environment variables

CLOVER_EXTRA_BUILD_OPTIONS

allows specifying additional compiler and linker options. Specified options are appended after the options set by the OpenCL program in clBuildProgram.

CLOVER_EXTRA_COMPILE_OPTIONS

allows specifying additional compiler options. Specified options are appended after the options set by the OpenCL program in clCompileProgram.

CLOVER_EXTRA_LINK_OPTIONS

allows specifying additional linker options. Specified options are appended after the options set by the OpenCL program in clLinkProgram.

Softpipe driver environment variables

SOFTPIPE_DEBUG

a comma-separated list of named flags, which do various things:

vs

Dump vertex shader assembly to stderr

fs

Dump fragment shader assembly to stderr

gs

Dump geometry shader assembly to stderr

cs

Dump compute shader assembly to stderr

no_rast

rasterization is disabled. For profiling purposes.

use_llvm

the softpipe driver will try to use LLVM JIT for vertex shading processing.

use_tgsi

if set, the softpipe driver will ask to directly consume TGSI, instead of NIR.

LLVMpipe driver environment variables

LP_NO_RAST

if set LLVMpipe will no-op rasterization

LP_DEBUG

a comma-separated list of debug options is accepted. See the source code for details.

LP_PERF

a comma-separated list of options to selectively no-op various parts of the driver. See the source code for details.

LP_NUM_THREADS

an integer indicating how many threads to use for rendering. Zero turns off threading completely. The default value is the number of CPU cores present.

VMware SVGA driver environment variables

:envvar`SVGA_FORCE_SWTNL`

force use of software vertex transformation

:envvar`SVGA_NO_SWTNL`

don’t allow software vertex transformation fallbacks (will often result in incorrect rendering).

:envvar`SVGA_DEBUG`

for dumping shaders, constant buffers, etc. See the code for details.

:envvar`SVGA_EXTRA_LOGGING`

if set, enables extra logging to the vmware.log file, such as the OpenGL program’s name and command line arguments.

:envvar`SVGA_NO_LOGGING`

if set, disables logging to the vmware.log file. This is useful when using Valgrind because it otherwise crashes when initializing the host log feature.

See the driver code for other, lesser-used variables.

WGL environment variables

WGL_SWAP_INTERVAL

to set a swap interval, equivalent to calling wglSwapIntervalEXT() in an application. If this environment variable is set, application calls to wglSwapIntervalEXT() will have no effect.

VA-API environment variables

VAAPI_MPEG4_ENABLED

enable MPEG4 for VA-API, disabled by default.

VC4 driver environment variables

VC4_DEBUG

a comma-separated list of named flags, which do various things:

cl

dump command list during creation

qpu

dump generated QPU instructions

qir

dump QPU IR during program compile

nir

dump NIR during program compile

tgsi

dump TGSI during program compile

shaderdb

dump program compile information for shader-db analysis

perf

print during performance-related events

norast

skip actual hardware execution of commands

always_flush

flush after each draw call

always_sync

wait for finish after each flush

dump

write a GPU command stream trace file (VC4 simulator only)

RADV driver environment variables

RADV_DEBUG

a comma-separated list of named flags, which do various things:

llvm

enable LLVM compiler backend

allbos

force all allocated buffers to be referenced in submissions

checkir

validate the LLVM IR before LLVM compiles the shader

forcecompress

Enables DCC,FMASK,CMASK,HTILE in situations where the driver supports it but normally does not deem it beneficial.

hang

enable GPU hangs detection and dump a report to $HOME/radv_dumps_<pid>_<time> if a GPU hang is detected

img

Print image info

info

show GPU-related information

invariantgeom

Mark geometry-affecting outputs as invariant. This works around a common class of application bugs appearing as flickering.

metashaders

dump internal meta shaders

noatocdithering

disable dithering for alpha to coverage

nobinning

disable primitive binning

nocache

disable shaders cache

nocompute

disable compute queue

nodcc

disable Delta Color Compression (DCC) on images

nodisplaydcc

disable Delta Color Compression (DCC) on displayable images

nodynamicbounds

do not check OOB access for dynamic descriptors

nofastclears

disable fast color/depthstencil clears

nohiz

disable HIZ for depthstencil images

noibs

disable directly recording command buffers in GPU-visible memory

nomemorycache

disable memory shaders cache

nongg

disable NGG for GFX10+

nonggc

disable NGG culling on GPUs where it’s enabled by default (GFX10.3+ only).

nooutoforder

disable out-of-order rasterization

notccompatcmask

disable TC-compat CMASK for MSAA surfaces

noumr

disable UMR dumps during GPU hang detection (only with RADV_DEBUG`=``hang`)

novrsflatshading

disable VRS for flat shading (only on GFX10.3+)

preoptir

dump LLVM IR before any optimizations

prologs

dump vertex shader prologs

shaders

dump shaders

shaderstats

dump shader statistics

spirv

dump SPIR-V

startup

display info at startup

syncshaders

synchronize shaders after all draws/dispatches

vmfaults

check for VM memory faults via dmesg

zerovram

initialize all memory allocated in VRAM as zero

RADV_FORCE_FAMILY

create a null device to compile shaders without a AMD GPU (e.g. VEGA10)

RADV_FORCE_VRS

allow to force per-pipeline vertex VRS rates on GFX10.3+. This is only forced for pipelines that don’t explicitely use VRS or flat shading. The supported values are 2x2, 1x2 and 2x1. Only for testing purposes.

RADV_PERFTEST

a comma-separated list of named flags, which do various things:

bolist

enable the global BO list

cswave32

enable wave32 for compute shaders (GFX10+)

dccmsaa

enable DCC for MSAA images

force_emulate_rt

forces ray-tracing to be emulated in software, even if there is hardware support.

gewave32

enable wave32 for vertex/tess/geometry shaders (GFX10+)

localbos

enable local BOs

nosam

disable optimizations that get enabled when all VRAM is CPU visible.

pswave32

enable wave32 for pixel shaders (GFX10+)

nggc

enable NGG culling on GPUs where it’s not enabled by default (GFX10.1 only).

rt

enable rt extensions whose implementation is still experimental.

sam

enable optimizations to move more driver internal objects to VRAM.

RADV_TEX_ANISO

force anisotropy filter (up to 16)

RADV_THREAD_TRACE

enable frame based SQTT/RGP captures (eg. export RADV_THREAD_TRACE=100 will capture the frame #100)

RADV_THREAD_TRACE_BUFFER_SIZE

set the SQTT/RGP buffer size in bytes (default value is 32MiB, the buffer is automatically resized if too small)

RADV_THREAD_TRACE_CACHE_COUNTERS

enable/disable SQTT/RGP cache counters on GFX10+ (disabled by default)

RADV_THREAD_TRACE_INSTRUCTION_TIMING

enable/disable SQTT/RGP instruction timing (enabled by default)

RADV_THREAD_TRACE_TRIGGER

enable trigger file based SQTT/RGP captures (eg. export RADV_THREAD_TRACE_TRIGGER=/tmp/radv_sqtt_trigger and then touch /tmp/radv_sqtt_trigger to capture a frame)

ACO_DEBUG

a comma-separated list of named flags, which do various things:

validateir

validate the ACO IR at various points of compilation (enabled by default for debug/debugoptimized builds)

validatera

validate register assignment of ACO IR and catches many RA bugs

perfwarn

abort on some suboptimal code generation

force-waitcnt

force emitting waitcnt states if there is something to wait for

novn

disable value numbering

noopt

disable various optimizations

noscheduling

disable instructions scheduling

perfinfo

print information used to calculate some pipeline statistics

liveinfo

print liveness and register demand information before scheduling

radeonsi driver environment variables

AMD_DEBUG

a comma-separated list of named flags, which do various things:

nodcc

Disable DCC.

nodccclear

Disable DCC fast clear.

nodccmsaa

Disable DCC for MSAA

nodpbb

Disable DPBB.

nodfsm

Disable DFSM.

notiling

Disable tiling

nofmask

Disable MSAA compression

nohyperz

Disable Hyper-Z

no2d

Disable 2D tiling

info

Print driver information

tex

Print texture info

compute

Print compute info

vm

Print virtual addresses when creating resources

vs

Print vertex shaders

ps

Print pixel shaders

gs

Print geometry shaders

tcs

Print tessellation control shaders

tes

Print tessellation evaluation shaders

cs

Print compute shaders

noir

Don’t print the LLVM IR

nonir

Don’t print NIR when printing shaders

noasm

Don’t print disassembled shaders

preoptir

Print the LLVM IR before initial optimizations

gisel

Enable LLVM global instruction selector.

w32ge

Use Wave32 for vertex, tessellation, and geometry shaders.

w32ps

Use Wave32 for pixel shaders.

w32cs

Use Wave32 for computes shaders.

w64ge

Use Wave64 for vertex, tessellation, and geometry shaders.

w64ps

Use Wave64 for pixel shaders.

w64cs

Use Wave64 for computes shaders.

checkir

Enable additional sanity checks on shader IR

mono

Use old-style monolithic shaders compiled on demand

nooptvariant

Disable compiling optimized shader variants.

nowc

Disable GTT write combining

check_vm

Check VM faults and dump debug info.

reserve_vmid

Force VMID reservation per context.

nogfx

Disable graphics. Only multimedia compute paths can be used.

nongg

Disable NGG and use the legacy pipeline.

nggc

Always use NGG culling even when it can hurt.

nonggc

Disable NGG culling.

switch_on_eop

Program WD/IA to switch on end-of-packet.

nooutoforder

Disable out-of-order rasterization

dpbb

Enable DPBB.

dfsm

Enable DFSM.

r600 driver environment variables

R600_DEBUG

a comma-separated list of named flags, which do various things:

nocpdma

Disable CP DMA

nosb

Disable sb backend for graphics shaders

sbcl

Enable sb backend for compute shaders

sbdry

Don’t use optimized bytecode (just print the dumps)

sbstat

Print optimization statistics for shaders

sbdump

Print IR dumps after some optimization passes

sbnofallback

Abort on errors instead of fallback

sbdisasm

Use sb disassembler for shader dumps

sbsafemath

Disable unsafe math optimizations

nirsb

Enable NIR with SB optimizer

tex

Print texture info

nir

Enable experimental NIR shaders

compute

Print compute info

vm

Print virtual addresses when creating resources

info

Print driver information

fs

Print fetch shaders

vs

Print vertex shaders

gs

Print geometry shaders

ps

Print pixel shaders

cs

Print compute shaders

tcs

Print tessellation control shaders

tes

Print tessellation evaluation shaders

noir

Don’t print the LLVM IR

notgsi

Don’t print the TGSI

noasm

Don’t print disassembled shaders

preoptir

Print the LLVM IR before initial optimizations

checkir

Enable additional sanity checks on shader IR

nooptvariant

Disable compiling optimized shader variants.

testdma

Invoke SDMA tests and exit.

testvmfaultcp

Invoke a CP VM fault test and exit.

testvmfaultsdma

Invoke a SDMA VM fault test and exit.

testvmfaultshader

Invoke a shader VM fault test and exit.

nodma

Disable asynchronous DMA

nohyperz

Disable Hyper-Z

noinvalrange

Disable handling of INVALIDATE_RANGE map flags

no2d

Disable 2D tiling

notiling

Disable tiling

switch_on_eop

Program WD/IA to switch on end-of-packet.

forcedma

Use asynchronous DMA for all operations when possible.

precompile

Compile one shader variant at shader creation.

nowc

Disable GTT write combining

check_vm

Check VM faults and dump debug info.

unsafemath

Enable unsafe math shader optimizations

R600_DEBUG_COMPUTE

if set to true, various compute-related debug information will be printed to stderr. Defaults to false.

R600_DUMP_SHADERS

if set to true, NIR shaders will be printed to stderr. Defaults to false.

R600_HYPERZ

If set to false, disables HyperZ optimizations. Defaults to true.

R600_NIR_DEBUG

a comma-separated list of named flags, which do various things:

instr

Log all consumed nir instructions

ir

Log created R600 IR

cc

Log R600 IR to assembly code creation

noerr

Don’t log shader conversion errors

si

Log shader info (non-zero values)

reg

Log register allocation and lookup

io

Log shader in and output

ass

Log IR to assembly conversion

flow

Log control flow instructions

merge

Log register merge operations

nomerge

Skip register merge step

tex

Log texture ops

trans

Log generic translation messages

r300 driver environment variables

RADEON_DEBUG

a comma-separated list of named flags, which do various things:

info

Print hardware info (printed by default on debug builds

fp

Log fragment program compilation

vp

Log vertex program compilation

draw

Log draw calls

swtcl

Log SWTCL-specific info

rsblock

Log rasterizer registers

psc

Log vertex stream registers

tex

Log basic info about textures

texalloc

Log texture mipmap tree info

rs

Log rasterizer

fb

Log framebuffer

cbzb

Log fast color clear info

hyperz

Log HyperZ info

scissor

Log scissor info

msaa

Log MSAA resources

anisohq

Use high quality anisotropic filtering

notiling

Disable tiling

noimmd

Disable immediate mode

noopt

Disable shader optimizations

nocbzb

Disable fast color clear

nozmask

Disable zbuffer compression

nohiz

Disable hierarchical zbuffer

nocmask

Disable AA compression and fast AA clear

use_tgsi

Request TGSI shaders from the state tracker

notcl

Disable hardware accelerated Transform/Clip/Lighting

Other Gallium drivers have their own environment variables. These may change frequently so the source code should be consulted for details.