1 ============== 1 ==============
2 What is efifb? 2 What is efifb?
3 ============== 3 ==============
4 4
5 This is a generic EFI platform driver for syst !! 5 This is a generic EFI platform driver for Intel based Apple computers.
6 system must be booted via the EFI stub for thi !! 6 efifb is only for EFI booted Intel Macs.
7 both firmware with Graphics Output Protocol (G <<
8 systems with only Universal Graphics Adapter ( <<
9 7
10 Supported Hardware 8 Supported Hardware
11 ================== 9 ==================
12 10
13 - iMac 17"/20" 11 - iMac 17"/20"
14 - Macbook 12 - Macbook
15 - Macbook Pro 15"/17" 13 - Macbook Pro 15"/17"
16 - MacMini 14 - MacMini
17 - ARM/ARM64/X86 systems with UEFI firmware <<
18 15
19 How to use it? 16 How to use it?
20 ============== 17 ==============
21 18
22 For UGA displays, efifb does not have any kind !! 19 efifb does not have any kind of autodetection of your machine.
23 machine. <<
24 <<
25 You have to add the following kernel parameter 20 You have to add the following kernel parameters in your elilo.conf::
26 21
27 Macbook : 22 Macbook :
28 video=efifb:macbook 23 video=efifb:macbook
29 MacMini : 24 MacMini :
30 video=efifb:mini 25 video=efifb:mini
31 Macbook Pro 15", iMac 17" : 26 Macbook Pro 15", iMac 17" :
32 video=efifb:i17 27 video=efifb:i17
33 Macbook Pro 17", iMac 20" : 28 Macbook Pro 17", iMac 20" :
34 video=efifb:i20 29 video=efifb:i20
35 30
36 For GOP displays, efifb can autodetect the dis <<
37 address, so these should work out of the box w <<
38 <<
39 Accepted options: 31 Accepted options:
40 32
41 ======= ====================================== 33 ======= ===========================================================
42 nowc Don't map the framebuffer write combin 34 nowc Don't map the framebuffer write combined. This can be used
43 to workaround side-effects and slowdow 35 to workaround side-effects and slowdowns on other CPU cores
44 when large amounts of console data are 36 when large amounts of console data are written.
45 ======= ====================================== 37 ======= ===========================================================
46 <<
47 Options for GOP displays: <<
48 <<
49 mode=n <<
50 The EFI stub will set the mode of the <<
51 possible. <<
52 <<
53 <xres>x<yres>[-(rgb|bgr|<bpp>)] <<
54 The EFI stub will search for a display <<
55 horizontal and vertical resolution, an <<
56 the mode of the display to it if one i <<
57 "rgb" or "bgr" to match specifically t <<
58 for a mode with matching bits per pixe <<
59 <<
60 auto <<
61 The EFI stub will choose the mode with <<
62 of horizontal and vertical resolution) <<
63 with the highest resolution, it will c <<
64 depth. <<
65 <<
66 list <<
67 The EFI stub will list out all the dis <<
68 specific mode can then be chosen using <<
69 next boot. <<
70 38
71 Edgar Hucek <gimli@dark-green.com> 39 Edgar Hucek <gimli@dark-green.com>
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