| Mauro Carvalho Chehab | ab42b81 | 2019-06-12 14:52:45 -0300 | [diff] [blame] | 1 | =============== |
| 2 | What is pvr2fb? |
| 3 | =============== |
| 4 | |
| 5 | This is a driver for PowerVR 2 based graphics frame buffers, such as the |
| 6 | one found in the Dreamcast. |
| 7 | |
| 8 | Advantages: |
| 9 | |
| 10 | * It provides a nice large console (128 cols + 48 lines with 1024x768) |
| 11 | without using tiny, unreadable fonts (NOT on the Dreamcast) |
| 12 | * You can run XF86_FBDev on top of /dev/fb0 |
| 13 | * Most important: boot logo :-) |
| 14 | |
| 15 | Disadvantages: |
| 16 | |
| 17 | * Driver is largely untested on non-Dreamcast systems. |
| 18 | |
| 19 | Configuration |
| 20 | ============= |
| 21 | |
| 22 | You can pass kernel command line options to pvr2fb with |
| 23 | `video=pvr2fb:option1,option2:value2,option3` (multiple options should be |
| 24 | separated by comma, values are separated from options by `:`). |
| 25 | |
| 26 | Accepted options: |
| 27 | |
| 28 | ========== ================================================================== |
| 29 | font:X default font to use. All fonts are supported, including the |
| 30 | SUN12x22 font which is very nice at high resolutions. |
| 31 | |
| 32 | |
| 33 | mode:X default video mode with format [xres]x[yres]-<bpp>@<refresh rate> |
| 34 | The following video modes are supported: |
| 35 | 640x640-16@60, 640x480-24@60, 640x480-32@60. The Dreamcast |
| 36 | defaults to 640x480-16@60. At the time of writing the |
| 37 | 24bpp and 32bpp modes function poorly. Work to fix that is |
| 38 | ongoing |
| 39 | |
| 40 | Note: the 640x240 mode is currently broken, and should not be |
| 41 | used for any reason. It is only mentioned here as a reference. |
| 42 | |
| 43 | inverse invert colors on screen (for LCD displays) |
| 44 | |
| 45 | nomtrr disables write combining on frame buffer. This slows down driver |
| 46 | but there is reported minor incompatibility between GUS DMA and |
| 47 | XFree under high loads if write combining is enabled (sound |
| 48 | dropouts). MTRR is enabled by default on systems that have it |
| 49 | configured and that support it. |
| 50 | |
| 51 | cable:X cable type. This can be any of the following: vga, rgb, and |
| 52 | composite. If none is specified, we guess. |
| 53 | |
| 54 | output:X output type. This can be any of the following: pal, ntsc, and |
| 55 | vga. If none is specified, we guess. |
| 56 | ========== ================================================================== |
| 57 | |
| 58 | X11 |
| 59 | === |
| 60 | |
| 61 | XF86_FBDev has been shown to work on the Dreamcast in the past - though not yet |
| 62 | on any 2.6 series kernel. |
| 63 | |
| 64 | Paul Mundt <lethal@linuxdc.org> |
| 65 | |
| 66 | Updated by Adrian McMenamin <adrian@mcmen.demon.co.uk> |