1FBTURBO(4) Kernel Interfaces Manual FBTURBO(4)
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6 fbturbo - video driver for Allwinner and other ARM-based devices
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9 Section "Device"
10 Identifier "devname"
11 Driver "fbturbo"
12 ...
13 EndSection
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16 fbturbo is an Xorg driver for Allwinner and other ARM-based devices,
17 derived from fbdev driver. With regard to 2D graphics, it provides a
18 number of software optimizations on all platforms, while letting the
19 SIMD (ARM NEON) accelerated code from the pixman library run at full
20 speed without any unnecessary overhead. 2D hardware acceleration using
21 G2D is supported on sunxi platforms. The recommended framebuffer color
22 depths are 16 (RGB565) and 24 (XRGB8888), the other color depths may be
23 supported too. Multi-head configurations are supported.
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26 The fbturbo driver supports all hardware where a framebuffer driver is
27 available and uses the os-specific submodule fbdevhw(4) to talk to the
28 kernel device driver. Currently a fbdevhw module is available for
29 linux. Additionally it is intended to use some of the display con‐
30 troller features from Allwinner A10/A13 SoC and provide the necessary
31 DRI2 integration with the proprietary OpenGL ES binary blobs for
32 Mali400 GPU (if they are installed in the system). The part related to
33 Mali400 GPU support is derived from the vendor provided open source
34 xf86-video-mali driver.
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37 Please refer to xorg.conf(5) for general configuration details. This
38 section only covers configuration details specific to this driver.
39 For this driver it is not required to specify modes in the screen sec‐
41 tion of the config file. The fbturbo driver can pick up the currently
42 used video mode from the framebuffer driver and will use it if there
43 are no video modes configured.
44 The following driver Options are supported:
46 Option "fbdev" "string"
48 The framebuffer device to use. Default: /dev/fb0.
49 Option "ShadowFB" "boolean"
51 Enable or disable use of the shadow framebuffer layer. Default:
52 off on most platforms (any hardware that supports NEON, VFP, or
53 2D hardware acceleration).
54 Option "Rotate" "string"
56 Enable rotation of the display. The supported values are "CW"
57 (clockwise, 90 degrees), "UD" (upside down, 180 degrees) and
58 "CCW" (counter clockwise, 270 degrees). Implies use of the
59 shadow framebuffer layer. Default: off.
60 Option "UseBackingStore" "boolean"
62 Enable the use of backing store for certain windows at the bot‐
63 tom of the stacking order. This allows to avoid expensive
64 redraws caused by expose events when dragging one window on top
65 of another. The default heuristics tries to be "smart" and avoid
66 backing store allocation for the active window which has key‐
67 board focus. The purpose is to get the best balance between per‐
68 formance and memory footprint without introducing full composit‐
69 ing overhead. Default: inverse of ShadowFB
70 Option "ForceBackingStore" "boolean"
72 Same as "UseBackingStore" option, but don't apply any heuristics
73 and just allocate backing store for all windows.
74 Option "HWCursor" "boolean"
76 Enable or disable the HW cursor. Supported on sunxi platforms.
77 Default: on if supported, off otherwise.
78 Option "DRI2" "boolean"
80 Enable or disable DRI2 integration for Mali GPU. Provides hard‐
81 ware accelerated OpenGL ES in the case if proprietary blob lib‐
82 Mali.so is installed in the system and linux kernel provides
83 modules mali.ko, mali_drm.ko and ump.ko with compatible version
84 (for example, both kernel modules and libMali.so can have revi‐
85 sion r3p0). Default: on.
86 Option "DRI2HWOverlay" "boolean"
88 Enable the use of display controller hardware overlays (aka
89 "layers", "windows", ...) for fully visible DRI2 backed OpenGL
90 ES windows in order to avoid expensive memory copy operations.
91 That's a zero-copy solution which eliminates unnecessary CPU
92 overhead. Default: on.
93 Note: the hardware overlays are automatically disabled in the
95 case if a compositing window manager (xfwm4, kwin, ...) is used
96 for various fancy desktop effects such as windows translucency
97 or shadows. Maybe some improvements are possible in this area.
98 But if you really care about the desktop performance, then you
99 likely don't want to enable any compositing effects in your win‐
100 dow manager anyway.
101 Option "SwapbuffersWait" "boolean"
103 This option controls the behavior of eglSwapBuffers calls by
104 OpenGL ES applications. If enabled, the calls will try to avoid
105 tearing by making sure the display scanline is outside of the
106 area to be copied before the copy occurs. If disabled, no scan‐
107 line synchronization is performed, meaning tearing will likely
108 occur. Note that when enabled, this option can adversely affect
109 the framerate of applications that render frames at less than
110 refresh rate. Default: enabled.
111 Option "AccelMethod" "string"
113 Chooses between available acceleration architectures. Valid val‐
114 ues are G2D and CPU. G2D is only available on sunxi hardware
115 with G2D support (such as A10). The default is G2D on supported
116 platforms, CPU on others.
117 Option "XVHWOverlay" "boolean"
120 Enable or disable the use of display controller hardware over‐
121 lays for XVideo acceleration. Only available on sunxi hardware.
122 Default: on if supported, off otherwise.
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126 Xorg(1), xorg.conf(5), Xserver(1), X(7), fbdevhw(4)
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129 Authors include: Gerd Knorr, Michel Dänzer, Geert Uytterhoeven, Siarhei
130 Siamashka
131X Version 11 xf86-video-fbturbo 0.5.1 FBTURBO(4)