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Afree and open-source graphics device driver is asoftware stack which controls computer-graphics hardware and supportsgraphics-rendering application programming interfaces (APIs) and is released under afree and open-source software license. Graphicsdevice drivers are written for specific hardware to work within a specificoperating system kernel and to support a range of APIs used by applications to access the graphics hardware. They may also control output to the display if thedisplay driver is part of the graphics hardware. Most free and open-source graphics device drivers are developed by theMesa project. The driver is made up of acompiler, arendering API, and software which manages access to the graphics hardware.
Drivers without freely (and legally) availablesource code are commonly known asbinary drivers. Binary drivers used in the context ofoperating systems that are prone to ongoing development and change (such as Linux) create problems for end users andpackage maintainers. These problems, which affect system stability, security and performance, are the main reason for the independent development of free and open-source drivers. When notechnical documentation is available, an understanding of the underlying hardware is often gained byclean-room reverse engineering. Based on this understanding, device drivers may be written and legally published under anysoftware license.
In rare cases, a manufacturer's driver source code is available on the Internet without afree license. This means that the code can be studied and altered for personal use, but the altered (and usually the original) source code cannot be freely distributed. Solutions to bugs in the driver cannot be easily shared in the form of modified versions of the driver. Therefore, the utility of such drivers is significantly reduced in comparison to free and open-source drivers.
There are objections to binary-only drivers based on copyright, security, reliability and development concerns. As part of a wider campaign againstbinary blobs,OpenBSD lead developerTheo de Raadt said that with a binary driver there is "no way to fix it when it breaks (and it will break)"; when a product which relies on binary drivers is declared to beend-of-life by the manufacturer, it is effectively "broken forever."[1] The project has also stated that binary drivers[2] "hide bugs and workarounds for bugs",[3] an observation which has been somewhat vindicated by flaws found in binary drivers (including anexploitablebug in Nvidia's 3D drivers discovered in October 2006 byRapid7). It is speculated that the bug has existed since 2004; Nvidia has denied this, asserting that the issue was only communicated to them in July 2006 and the 2004 bug was a bug in X.Org (not in Nvidia's driver).[4]
Binary drivers often do not work with current versions of open-source software, and rarely support development snapshots of open-source software; it is usually not directly possible for a developer to use Nvidia's or ATI's proprietary drivers with a development snapshot of an X server or a development snapshot of the Linux kernel. Features likekernel mode-setting cannot be added to binary drivers by anyone but the vendors, which prevents their inclusion if the vendor lacks capacity or interest.
In theLinux kernel development community,Linus Torvalds has made strong statements on the issue of binary-only modules: "Irefuse to even consider tying my hands over some binary-only module ... I want people to know that when they use binary-only modules, it'stheir problem".[5] Another kernel developer,Greg Kroah-Hartman, has said that a binary-only kernel module does not comply with the kernel's license (theGNU General Public License); it "just violates the GPL due to fun things like derivative works and linking and other stuff."[6] Writer and computer scientistPeter Gutmann has expressed concern that thedigital rights management scheme in Microsoft'sWindows Vista operating system may limit the availability of the documentation required to write open drivers, since it "requires that the operational details of the device be kept confidential."[7]
In the case of binary drivers, there are objections due tofree software philosophy, software quality andsecurity concerns.[8] In 2006,Greg Kroah-Hartman concluded that:
Closed source Linux kernel modules are illegal. That's it, it is very simple. I've had the misfortune of talking to a lot of different IP lawyers over the years about this topic, and every one that I've talked to all agree that there is no way that anyone can create a Linux kernel module, today, that can be closed source. It just violates theGPL due to fun things likederivative works andlinking.[9]
The Linux kernel has never maintained a stable in-kernelapplication binary interface.[10] There are also concerns that proprietary drivers may containbackdoors, like the one found inSamsung Galaxy-series modem drivers.[11]
When applications such as a 3Dgame engine or a3D computer graphics software shunt calculations from the CPU to the GPU, they usually use a special-purpose API likeOpenGL orDirect3D and do not address the hardware directly. Because alltranslation (from API calls to GPUopcodes) is done by the device driver, it contains specialized knowledge and is an object of optimization. Due to the history of the rigidity of proprietary driver development there has been a recent surge in the number of community-backed device drivers for desktop and mobile GPUs. Free and Open Hardware organizations like FOSSi, LowRISC, and others, would also benefit from the development of an open graphical hardware standard. This would then provide computer manufacturers, hobbyists, and the like with a complete, royalty-free platform with which to develop computing hardware and related devices.
Thedesktop computer market was long dominated by PC hardware using thex86/x86-64 instruction set and GPUs available for the PC. With three major competitors (Nvidia, AMD and Intel). The main competing factor was the price of hardware and raw performance in 3D computer games, which is greatly affected by the efficient translation of API calls into GPU opcodes. The display driver and thevideo decoder are inherent parts of the graphics card: hardware designed to assist in the calculations necessary for the decoding of video streams. As the market for PC hardware has dwindled, it seems unlikely that new competitors will enter this market and it is unclear how much more knowledge one company could gain by seeing the source code of other companies' drivers.
The mobile sector presents a different situation. The functional blocks (theapplication-specific integrated circuit display driver, 2D and 3D acceleration and video decoding and encoding) are separatesemiconductor intellectual property (SIP) blocks on the chip, since hardware devices vary substantially; someportable media players require a display driver that accelerates video decoding, but does not require 3D acceleration. The development goal is not only raw 3D performance, but system integration, power consumption and 2D capabilities. There is also an approach which abandons the traditional method (Vsync) of updating the display and makes better use ofsample and hold technology to lower power consumption.
During the second quarter of 2013 79.3% ofsmartphones sold worldwide were running a version ofAndroid,[12] and the Linux kernel dominates smartphones. Hardware developers have an incentive to deliver Linux drivers for their hardware but, due to competition, no incentive to make these drivers free and open-source. Additional problems are the Android-specific augmentations to the Linux kernel which have not been accepted inmainline, such as theAtomic Display Framework (ADF).[13] ADF is a feature of 3.10 AOSP kernels which provides adma-buf-centric framework between Android's hwcomposerHAL and the kernel driver. ADF significantly overlaps with theDRM-KMS framework. ADF has not been accepted into mainline, but a different set of solutions addressing the same problems (known asatomic mode setting) is under development. Projects such aslibhybris harness Android device drivers to run on Linux platforms other than Android.
Free and open-source drivers are primarily developed on and forLinux by Linux kernel developers, third-party programming enthusiasts and employees of companies such asAdvanced Micro Devices. Each driver has five parts:
TheDRM iskernel-specific. AVESA driver is generally available for any operating system. The VESA driver supports most graphics cards without acceleration and at display resolutions limited to a set programmed in the Video BIOS by the manufacturer.[15]
The Linux graphics stack has evolved, detoured by theX Window System core protocol.
glxinfo showing OpenGL information withglxgears running on a Linux system withAMDGPU kernel moduleAMD's proprietary driver,AMD Catalyst for theirRadeon, is available for Microsoft Windows and Linux (formerly fglrx). A current version can be downloaded from AMD's site, and some Linux distributions contain it in their repositories. It is in the process of being replaced with an AMDGPU-PRO hybrid driver combining the open-source kernel, X and Mesa multimedia drivers with closed-source OpenGL, OpenCL and Vulkan drivers derived from Catalyst.
The FOSS drivers forATI-AMD GPUs are being developed under the name Radeon (xf86-video-ati or xserver-xorg-video-radeon). They still must load proprietary microcode into the GPU to enable hardware acceleration.[16][failed verification]
Radeon 3D code is split into six drivers, according to GPU technology: the radeon, r200 and r300 classic drivers and r300g, r600g and radeonsiGallium3D drivers:
An up-to-date feature matrix is available,[17] and there is support forVideo Coding Engine[18] andUnified Video Decoder.[19][20] The free and open-source Radeon graphics device drivers are not reverse-engineered, but are based on documentation released by AMD without the requirement to sign anon-disclosure agreement (NDA).[21][22][23] Documentation began to be gradually released in 2007.[24][25][26]
In addition to providing the necessary documentation, AMD employees contribute code to support their hardware and features.[18]
All components of the Radeon graphics device driver are developed by core contributors and interested parties worldwide. In 2011, the r300g outperformed Catalyst in some cases.
At the 2014Game Developers Conference, AMD announced that they were exploring a strategy change to re-base the user-space part of Catalyst on a free and open-sourceDRM kernel module instead of their proprietary kernelblob.[27]
The release of the new AMDGPU kernel module and stack was announced on the dri-devel mailing list in April 2015.[28] Although AMDGPU only officially supportsGCN 1.2 and later graphics cards,[29] experimental support for GCN 1.0 and 1.1 graphics cards (which are only officially supported by the Radeon driver) may be enabled via a kernel parameter.[30][31] A separatelibdrm, libdrm-amdgpu, has been included since libdrm 2.4.63.[32]
The radeonsi 3D code mentioned in the prior Radeon paragraph is also used with amdgpu; the 3D driver has back ends for both radeon and amdgpu.
Nvidia's proprietary driver,Nvidia GeForce driver forGeForce, is available forWindowsx86/x86-64,Linux x86/x86-64/ARM,OS X 10.5 and later,Solaris x86/x86-64 andFreeBSD x86/x86-64. A current version can be downloaded from the Internet, and some Linux distributions contain it in their repositories. The 4 October 2013beta Nvidia GeForce driver 331.13 supports theEGL interface, enabling support forWayland in conjunction with this driver.[33][34]
Nvidia's free and open-source driver is named nv.[35] It is limited (supporting only 2D acceleration), andMatthew Garrett,Dirk Hohndel and others have called its source code confusing.[36][37][38] Nvidia decided to deprecate nv, not adding support forFermi or later GPUs andDisplayPort, in March 2010.[39]
In December 2009, Nvidia announced they would not support free graphics initiatives.[40] On 23 September 2013, the company announced that they would release some documentation of their GPUs.[41]
Nouveau is based almost entirely on information gained throughreverse engineering. This project aims to produce 3D acceleration for X.Org/Wayland usingGallium3D.[42] On March 26, 2012, Nouveau'sDRM component was marked stable and promoted from the staging area of the Linux kernel.[43] Nouveau supportsTesla- (and earlier),Fermi-,Kepler- andMaxwell-based GPUs.[44] On 31 January 2014, Nvidia employee Alexandre Courbot committed an extensive patch set which adds initial support for the GK20A (Tegra K1) to Nouveau.[45] In June 2014, Codethink reportedly ran aWayland-basedWestoncompositor withLinux kernel 3.15, usingEGL and a "100% open-source graphics driver stack" on aTegra K1.[46] A feature matrix is available.[47] In July 2014, Nouveau was unable to outperform the Nvidia GeForce driver due to missing re-clocking support. Tegra-re is a project which is working to reverse-engineer nVidia'sVLIW-basedTegra series of GPUs that predate Tegra K1.[48]
Nvidia distributes proprietary device drivers for Tegra through OEMs and as part of its Linux for Tegra (formerly L4T) development kit.[49] Nvidia and a partner,Avionic Design, were working on submitting Grate (free and open-source drivers for Tegra) upstream of the mainline Linux kernel in April 2012.[50][51]The company's co-founder and CEO laid out the Tegra processor roadmap with Ubuntu Unity at the 2013GPU Technology Conference.[52]
Nvidia's Unified Memory driver (nvidia-uvm.ko), which implements memory management for Pascal and Volta GPUs on Linux, is MIT licensed. The source code is available in the Nvidia Linux driver downloads on systems that support nvidia-uvm.ko.
In May 2022, Nvidia announced a new initiative and policy to open source itsGPULoadable Kernel Modules with dualGPL–MIT License, but only new models atalpha quality. But said "These changes are for the kernel modules, while the user-mode components are untouched. The user-mode remains closed source and is published with prebuilt binaries in the driver and the CUDA toolkit."[53] The open source driver has since been upgraded to production status and is now officially recommended for theRTX 20 series and later GPUs.[54][55]Blackwell (RTX 50 generation) and later NVIDIA GPU architectures are only supported by the open driver.[56]
Intel has a history of producing (or commissioning) open-source drivers for its graphics chips, with the exception of theirPowerVR-based chips.[57] Their 2D X.Org driver is called xf86-video-intel. The kernel mode-setting driver in the Linux kernel does not use thevideo BIOS for switchingvideo modes; since some BIOSes have a limited range of modes, this provides more reliable access to those supported by Intel video adapters.
The company worked on optimizing their freeLinux drivers for performance approaching theirWindows counterparts, especially onSandy Bridge and newer hardware where performance optimizations have allowed the Intel driver to outperform their proprietary Windows drivers in certain tasks, in 2011.[58][59][60] Some of the performance enhancements may also benefit users of older hardware.[61]
Support for Intel's LLC (Last Level Cache, L4-Cache,Crystalwell and Iris Pro) was added in Linux kernel 3.12.[62][63] In 2013, the company had 20 to 30 full-time Linux graphics developers.[64]
Matrox develops and manufactures theMatrox Mystique,Parhelia,G200,G400 andG550. Although the company provides free and open-source drivers for their chipsets which are older than the G550; chipsets newer than the G550 are supported by a closed-source driver.
S3 Graphics develops theS3 Trio,ViRGE,Savage andChrome, supported by OpenChrome.[65]
Arm Ltd is afabless semiconductor company which licensessemiconductor intellectual property cores. Although they are known for the licensing theARM instruction set andCPUs based on it, they also develop and license theMali series of GPUs, and more recently Imortalis GPUs that support ray-tracing. On January 21, 2012,Phoronix reported thatLuc Verhaegen was driving a reverse-engineering attempt aimed at the Arm Mali series of GPUs (specifically, the Mali-200 and Mali-400 versions). The reverse-engineering project, known as Lima, was presented atFOSDEM on February 4, 2012.[66][67] On February 2, 2013, Verhaegen demonstratedQuake III Arena in timedemo mode, running on top of the Lima driver.[68] In May 2018, a Lima developer posted the driver for inclusion in the Linux kernel.[69] As of May 2019, the Lima driver is part of the mainline Linux kernel.[70]
Panfrost is a reverse-engineered driver effort for Mali Txxx (Midgard) and Gxx (Bifrost) GPUs.Introducing Panfrost talk was presented at X.Org Developer's Conference 2018. As of May 2019, the Panfrost driver is part of the mainline Linux kernel.[71]
ARM has indicated no intention of providing support for their graphics acceleration hardware licensed under a free and open-source license. However, ARM employees sent patches for the Linux kernel to support their ARM HDLCDdisplay controller and Mali DP500, DP550 and DP650 SIP blocks in December 2015 and April 2016.[72][73]
Imagination Technologies is a fabless semiconductor company which develops and licensessemiconductor intellectual property cores, among which are thePowerVR GPUs. Intel has manufactured a number ofPowerVR-based GPUs. PowerVR GPUs are widely used in mobilesystem on a chip (SoC) devices. Due to its wide use in embedded devices, theFree Software Foundation has put reverse-engineering of the PowerVR driver on its high-priority project list.[74] As of March 2022, Imagination hasprovided a FOSS driver for itsRogue architecture-based PowerVR GX6250 from 2014, and its more recent A-Series architecture-based AXE-1-16M andBXS-4-64 GPUs.[75]
Vivante Corporation is a fabless semiconductor company which licensessemiconductor intellectual property cores and develops the GCxxxx series of GPUs. A Vivante proprietary, closed-source Linux driver consists of kernel- and user-space parts. Although the kernel component is open-source (GPL), the user-space components—consisting of the GLES(2) implementations and a HAL library—are not; these contain the bulk of the driver logic.
Wladimir J. van der Laan found and documented the state bits, command stream andshader ISA by studying how the blobs work, examining and manipulating command-stream dumps. The Etnaviv Gallium3D driver is being written based on this documentation. Van der Laan's work was inspired by the Lima driver, and the project has produced a functional-but-unoptimized Gallium3D LLVM driver. The Etnaviv driver has performed better than Vivante's proprietary code in some benchmarks, and it supports Vivante's GC400, GC800, GC1000, GC2000, GC3000 and GC7000 series.[76] In January 2017, Etnaviv was added toMesa with both OpenGL ES 2.0 and Desktop OpenGL 2.1 support.[77]
Qualcomm develops theAdreno (formerly ATIImageon) mobile GPU series, and includes it as part of theirSnapdragon mobile SoC series.Phoronix andSlashdot reported in 2012 that Rob Clark, inspired by the Lima driver, was working on reverse-engineering drivers for the Adreno GPU series.[78][79] In a referenced blog post, Clark wrote that he was doing the project in his spare time and that the Qualcomm platform was his only viable target for working on open 3D graphics. His employers (Texas Instruments andLinaro) were affiliated with theImaginationPowerVR andARM Mali cores, which would have been his primary targets; he had working command streams for 2D support, and 3D commands seemed to have the same characteristics.[80] The driver code was published onGitorious "freedreno",[81]and has been moved to Mesa.[82][83] In 2012, a working shader assembler was completed;[84]demonstration versions were developed fortexture mapping[85] andphong shading,[86] using the reverse-engineered shader compiler.Clark demonstrated Freedreno running desktop compositing, theXBMC media player andQuake III Arena atFOSDEM on February 2, 2013.[87]
In August 2013, the kernel component of freedreno (MSM driver) was accepted into mainline and is available in Linux kernel 3.12 and later.[88] TheDDX driver gained support for server-managedfile descriptors requiringX.Org Server version 1.16 and above in July 2014.[89] In January 2016, the Mesa Gallium3D-style driver gained support for Adreno 430;[90] in November of that year, the driver added support for the Adreno 500 series.[91] Freedreno can be used on devices such as96Boards Dragonboard 410c andNexus 7 (2013) in traditional Linux distributions (likeDebian andFedora) and onAndroid.
Broadcom develops and designs theVideoCore GPU series as part of theirSoCs. Since it is used by theRaspberry Pi, there has been considerable interest in a FOSS driver for VideoCore.[93] The Raspberry Pi Foundation, in co-operation with Broadcom, announced on October 24, 2012, that they open-sourced "all the ARM (CPU) code that drives the GPU".[citation needed] However, the announcement was misleading; according to the author of the reverse-engineered Lima driver, the newly open-sourced components only allowed message-passing between the ARM CPU and VideoCore but offered little insight into Videocore and little additional programability.[94] The Videocore GPU runs anRTOS which handles the processing; video acceleration is done with RTOS firmware coded for its proprietary GPU, and the firmware was not open-sourced on that date.[95] Since there was neither atoolchain targeting the proprietary GPU nor a documentedinstruction set, no advantage could be taken if the firmware source code became available. The Videocoreiv project[96] attempted to document the VideoCore GPUs.
On February 28, 2014 (the Raspberry Pi's second anniversary), Broadcom and the Raspberry Pi Foundation announced the release of full documentation for the VideoCore IV graphics core and a complete source release of the graphics stack under a3-clause BSD license.[97][98] The free-license 3D graphics code was committed to Mesa on 29 August 2014,[99] and first appeared on Mesa's 10.3 release.
AlthoughSilicon Integrated Systems andVIA Technologies have expressed limited interest in open-source drivers, both have released source code which has been integrated intoX.Org by FOSS developers.[38] In July 2008, VIA opened documentation of their products to improve its image in the Linux and open-source communities.[100] The company has failed to work with the open-source community to provide documentation and a workingDRM driver, leaving expectations of Linux support unfulfilled.[101] On January 6, 2011, it was announced that VIA was no longer interested in supporting free graphics initiatives.[102]
DisplayLink announced an open-source project, Libdlo,[103] with the goal of bringing support for theirUSB graphics technology toLinux and other platforms. Its code is available under theLGPL license,[104] but it has not been integrated into anX.Org driver. DisplayLink graphics support is available through the kernel udlfb driver (with fbdev) in mainline and udl/drm driver, which in March 2012 was only available in the drm-next tree.
Non-hardware-related vendors may also assist free graphics initiatives.Red Hat has two full-time employees (David Airlie and Jérôme Glisse) working on Radeon software,[105] and theFedora Project sponsors a Fedora Graphics Test Week event before the launch of their newLinux distribution versions to test free graphics drivers.[106] Other companies which have provided development or support includeNovell andVMware.
Project VGA aims to create a low-budget, open-sourceVGA-compatible video card.[107]TheOpen Graphics Project aimed to create an open-hardware GPU. In September 2010, the first 25 OGD1 boards were made available for grant application and purchase.[108] TheMilkymistsystem on a chip, targeted at embedded graphics instead of desktop computers, supports a VGA output, a limited vertex shader and a 2D texturing unit.[109]
The Nyuzi,[110] an experimental GPGPU processor, includes a synthesizable hardware design written inSystem Verilog, an instruction set emulator, anLLVM-based C-C++ compiler, software libraries and tests and explores parallel software and hardware. It can run on a Terasic DE2-115field-programmable gate array board.[111][112]
If a project uses FPGAs, it generally has a partially (or completely) closed-source toolchain. There are currently a couple of open-source toolchains available, however, for Lattice-based FPGAs (notably for iCE40 and ECP5 boards) which utilize Project IceStorm,[113] and Trellis,[114] respectively. There is also a larger, ongoing effort to create the "GCC of FPGAs" called SymbiFlow[115] which includes the aforementioned FPGA toolchains as well as an early-stage open-source toolchain for Xilinx-based FPGAs.
{{cite journal}}:Cite journal requires|journal= (help)... opposed to such obfuscated code. We do not regard this as free software according to our standards
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