projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| ab42b818 | 1 | ============== |
| a8557dc7 | 2 | What is efifb? |
| ab42b818 | 3 | ============== |
| b64ef8af | 4 | |
| fffb6804 AS |
5 | This is a generic EFI platform driver for systems with UEFI firmware. The |
| 6 | system must be booted via the EFI stub for this to be usable. efifb supports | |
| 7 | both firmware with Graphics Output Protocol (GOP) displays as well as older | |
| 8 | systems with only Universal Graphics Adapter (UGA) displays. | |
| b64ef8af EH |
9 | |
| 10 | Supported Hardware | |
| 11 | ================== | |
| 12 | ||
| ab42b818 MCC |
13 | - iMac 17"/20" |
| 14 | - Macbook | |
| 15 | - Macbook Pro 15"/17" | |
| 16 | - MacMini | |
| fffb6804 | 17 | - ARM/ARM64/X86 systems with UEFI firmware |
| b64ef8af EH |
18 | |
| 19 | How to use it? | |
| 20 | ============== | |
| 21 | ||
| fffb6804 AS |
22 | For UGA displays, efifb does not have any kind of autodetection of your |
| 23 | machine. | |
| 24 | ||
| ab42b818 MCC |
25 | You have to add the following kernel parameters in your elilo.conf:: |
| 26 | ||
| b64ef8af | 27 | Macbook : |
| a8557dc7 | 28 | video=efifb:macbook |
| b64ef8af | 29 | MacMini : |
| a8557dc7 | 30 | video=efifb:mini |
| b64ef8af | 31 | Macbook Pro 15", iMac 17" : |
| a8557dc7 | 32 | video=efifb:i17 |
| b64ef8af | 33 | Macbook Pro 17", iMac 20" : |
| a8557dc7 | 34 | video=efifb:i20 |
| b64ef8af | 35 | |
| fffb6804 AS |
36 | For GOP displays, efifb can autodetect the display's resolution and framebuffer |
| 37 | address, so these should work out of the box without any special parameters. | |
| 38 | ||
| dd0c41f8 DA |
39 | Accepted options: |
| 40 | ||
| ab42b818 | 41 | ======= =========================================================== |
| dd0c41f8 DA |
42 | nowc Don't map the framebuffer write combined. This can be used |
| 43 | to workaround side-effects and slowdowns on other CPU cores | |
| 44 | when large amounts of console data are written. | |
| ab42b818 | 45 | ======= =========================================================== |
| dd0c41f8 | 46 | |
| fffb6804 AS |
47 | Options for GOP displays: |
| 48 | ||
| 49 | mode=n | |
| 50 | The EFI stub will set the mode of the display to mode number n if | |
| 51 | possible. | |
| 52 | ||
| 9a1663bc | 53 | <xres>x<yres>[-(rgb|bgr|<bpp>)] |
| d9ff0323 | 54 | The EFI stub will search for a display mode that matches the specified |
| 9a1663bc AS |
55 | horizontal and vertical resolution, and optionally bit depth, and set |
| 56 | the mode of the display to it if one is found. The bit depth can either | |
| 57 | "rgb" or "bgr" to match specifically those pixel formats, or a number | |
| 58 | for a mode with matching bits per pixel. | |
| d9ff0323 | 59 | |
| 45d97a74 AS |
60 | auto |
| 61 | The EFI stub will choose the mode with the highest resolution (product | |
| 62 | of horizontal and vertical resolution). If there are multiple modes | |
| 63 | with the highest resolution, it will choose one with the highest color | |
| 64 | depth. | |
| 65 | ||
| 14c574f3 AS |
66 | list |
| 67 | The EFI stub will list out all the display modes that are available. A | |
| 68 | specific mode can then be chosen using one of the above options for the | |
| 69 | next boot. | |
| 70 | ||
| b64ef8af | 71 | Edgar Hucek <gimli@dark-green.com> |