1Intel 830M/845G/852GM/855GM/865G/915G/945G Framebuffer driver 2================================================================ 3 4A. Introduction 5 This is a framebuffer driver for various Intel 8xx/9xx compatible 6graphics devices. These would include: 7 8 Intel 830M 9 Intel 845G 10 Intel 852GM 11 Intel 855GM 12 Intel 865G 13 Intel 915G 14 Intel 915GM 15 Intel 945G 16 Intel 945GM 17 18B. List of available options 19 20 a. "video=intelfb" 21 enables the intelfb driver 22 23 Recommendation: required 24 25 b. "mode=<xres>x<yres>[-<bpp>][@<refresh>]" 26 select mode 27 28 Recommendation: user preference 29 (default = 1024x768-32@70) 30 31 c. "vram=<value>" 32 select amount of system RAM in MB to allocate for the video memory 33 if not enough RAM was already allocated by the BIOS. 34 35 Recommendation: 1 - 4 MB. 36 (default = 4 MB) 37 38 d. "voffset=<value>" 39 select at what offset in MB of the logical memory to allocate the 40 framebuffer memory. The intent is to avoid the memory blocks 41 used by standard graphics applications (XFree86). Depending on your 42 usage, adjust the value up or down, (0 for maximum usage, 63/127 MB 43 for the least amount). Note, an arbitrary setting may conflict 44 with XFree86. 45 46 Recommendation: do not set 47 (default = 48 MB) 48 49 e. "accel" 50 enable text acceleration. This can be enabled/reenabled anytime 51 by using 'fbset -accel true/false'. 52 53 Recommendation: enable 54 (default = set) 55 56 f. "hwcursor" 57 enable cursor acceleration. 58 59 Recommendation: enable 60 (default = set) 61 62 g. "mtrr" 63 enable MTRR. This allows data transfers to the framebuffer memory 64 to occur in bursts which can significantly increase performance. 65 Not very helpful with the intel chips because of 'shared memory'. 66 67 Recommendation: set 68 (default = set) 69 70 h. "fixed" 71 disable mode switching. 72 73 Recommendation: do not set 74 (default = not set) 75 76 The binary parameters can be unset with a "no" prefix, example "noaccel". 77 The default parameter (not named) is the mode. 78 79C. Kernel booting 80 81Separate each option/option-pair by commas (,) and the option from its value 82with an equals sign (=) as in the following: 83 84video=intelfb:option1,option2=value2 85 86Sample Usage 87------------ 88 89In /etc/lilo.conf, add the line: 90 91append="video=intelfb:mode=800x600-32@75,accel,hwcursor,vram=8" 92 93This will initialize the framebuffer to 800x600 at 32bpp and 75Hz. The 94framebuffer will use 8 MB of System RAM. hw acceleration of text and cursor 95will be enabled. 96 97Remarks 98------- 99 100If setting this parameter doesn't work (you stay in a 80x25 text-mode), 101you might need to set the "vga=<mode>" parameter too - see vesafb.txt 102in this directory. 103 104 105D. Module options 106 107 The module parameters are essentially similar to the kernel 108parameters. The main difference is that you need to include a Boolean value 109(1 for TRUE, and 0 for FALSE) for those options which don't need a value. 110 111Example, to enable MTRR, include "mtrr=1". 112 113Sample Usage 114------------ 115 116Using the same setup as described above, load the module like this: 117 118 modprobe intelfb mode=800x600-32@75 vram=8 accel=1 hwcursor=1 119 120Or just add the following to /etc/modprobe.conf 121 122 options intelfb mode=800x600-32@75 vram=8 accel=1 hwcursor=1 123 124and just do a 125 126 modprobe intelfb 127 128 129E. Acknowledgment: 130 131 1. Geert Uytterhoeven - his excellent howto and the virtual 132 framebuffer driver code made this possible. 133 134 2. Jeff Hartmann for his agpgart code. 135 136 3. David Dawes for his original kernel 2.4 code. 137 138 4. The X developers. Insights were provided just by reading the 139 XFree86 source code. 140 141 5. Antonino A. Daplas for his inspiring i810fb driver. 142 143 6. Andrew Morton for his kernel patches maintenance. 144 145########################### 146Sylvain 147