You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
251 lines
7.3 KiB
251 lines
7.3 KiB
/****************************************************************************
|
|
**
|
|
** Windowsystem-specific pages
|
|
**
|
|
** Copyright (C) 2000-2008 Trolltech ASA. All rights reserved.
|
|
**
|
|
** This file is part of the Qt GUI Toolkit.
|
|
**
|
|
** This file may be used under the terms of the GNU General
|
|
** Public License versions 2.0 or 3.0 as published by the Free
|
|
** Software Foundation and appearing in the files LICENSE.GPL2
|
|
** and LICENSE.GPL3 included in the packaging of this file.
|
|
** Alternatively you may (at your option) use any later version
|
|
** of the GNU General Public License if such license has been
|
|
** publicly approved by Trolltech ASA (or its successors, if any)
|
|
** and the KDE Free Qt Foundation.
|
|
**
|
|
** Please review the following information to ensure GNU General
|
|
** Public Licensing requirements will be met:
|
|
** http://trolltech.com/products/qt/licenses/licensing/opensource/.
|
|
** If you are unsure which license is appropriate for your use, please
|
|
** review the following information:
|
|
** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
|
|
** or contact the sales department at sales@trolltech.com.
|
|
**
|
|
** This file may be used under the terms of the Q Public License as
|
|
** defined by Trolltech ASA and appearing in the file LICENSE.QPL
|
|
** included in the packaging of this file. Licensees holding valid Qt
|
|
** Commercial licenses may use this file in accordance with the Qt
|
|
** Commercial License Agreement provided with the Software.
|
|
**
|
|
** This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
|
|
** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR
|
|
** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted
|
|
** herein.
|
|
**
|
|
**********************************************************************/
|
|
|
|
/*!
|
|
\page emb-framebuffer-howto.html
|
|
|
|
\title Enabling the Linux Framebuffer
|
|
|
|
This is only a short guide.
|
|
See \l file:/usr/src/linux/README and
|
|
\l file:/usr/src/linux/Documentation/fb/ for detailed information.
|
|
There is also a detailed explanation at
|
|
\l http://www.linuxdoc.org/HOWTO/Framebuffer-HOWTO.html.
|
|
|
|
\list 1
|
|
\i Make sure that you have the Linux kernel source code in
|
|
\l file:/usr/src/linux/.
|
|
|
|
\i Log in as root and \c cd \c /usr/src/linux
|
|
|
|
\i Configure the kernel:
|
|
|
|
Run:
|
|
\code
|
|
make menuconfig
|
|
\endcode
|
|
|
|
Select "Code maturity level options" and set "Prompt for
|
|
development and/or incomplete code/drivers".
|
|
|
|
Then select "Console drivers" and set "Support for frame buffer
|
|
devices" to built-in (even if it says EXPERIMENTAL). Then configure
|
|
the driver. Most modern graphics cards can use the "VESA VGA
|
|
graphics console"; use that or a driver that specifically matches
|
|
your video card. Finally, enable "Advanced low level driver options"
|
|
and make sure that 16 and 32 bpp packed pixel support are enabled.
|
|
|
|
When you are finished, chose exit and save.
|
|
|
|
\i Compile the kernel
|
|
|
|
First do:
|
|
\code
|
|
make dep
|
|
\endcode
|
|
then:
|
|
\code
|
|
make bzImage
|
|
\endcode
|
|
|
|
The new kernel should now be in arch/i386/boot/bzImage.
|
|
|
|
\i Copy the kernel to the boot directory:
|
|
\code
|
|
cp arch/i386/boot/bzImage /boot/linux.vesafb
|
|
\endcode
|
|
|
|
\i Edit /etc/lilo.conf.
|
|
|
|
\warning Keep a backup of \l file:/etc/lilo.conf, and have a rescue disk
|
|
available. If you make a mistake, the machine may not boot.
|
|
|
|
The file \l file:/etc/lilo.conf specifies how the system boots. The
|
|
precise contents of the file varies from system to system. Here is
|
|
an example:
|
|
\code
|
|
# LILO configuration file
|
|
boot = /dev/hda3
|
|
delay = 30
|
|
image = /boot/vmlinuz
|
|
root = /dev/hda3
|
|
label = Linux
|
|
read-only # Non-UMSDOS filesystems should be mounted read-only for checking
|
|
other=/dev/hda1
|
|
label=nt
|
|
table=/dev/hda
|
|
\endcode
|
|
|
|
Make a new "image" section that is a copy of the first one, but with
|
|
\code
|
|
image = /boot/linux.vesafb
|
|
\endcode
|
|
and
|
|
\code
|
|
label = Linux-vesafb
|
|
\endcode
|
|
Place it just above the first image section.
|
|
|
|
Add a line before the image section saying \c{vga = 791}. (Meaning
|
|
1024x768, 16 bpp.)
|
|
|
|
With the above example, lilo.conf would now be:
|
|
\code
|
|
# LILO configuration file
|
|
boot = /dev/hda3
|
|
delay = 30
|
|
vga = 791
|
|
image = /boot/linux.vesafb
|
|
root = /dev/hda3
|
|
label = Linux-vesafb
|
|
read-only # Non-UMSDOS filesystems should be mounted read-only for checking
|
|
image = /boot/vmlinuz
|
|
root = /dev/hda3
|
|
label = Linux
|
|
read-only # Non-UMSDOS filesystems should be mounted read-only for checking
|
|
other=/dev/hda1
|
|
label=nt
|
|
table=/dev/hda
|
|
\endcode
|
|
|
|
Do not change any existing lines in the file; just add new ones.
|
|
|
|
\i To make the new changes take effect, run the lilo program:
|
|
\code
|
|
lilo
|
|
\endcode
|
|
|
|
\i Reboot the system. You should now see a penguin logo while the
|
|
system is booting.
|
|
(Or more than one on a multi-processor machine.)
|
|
|
|
\i If it does not boot properly with the new kernel, you can boot with
|
|
the old kernel by entering the label of the old image section at
|
|
the LILO prompt. (with the example lilo.conf file, the old label is
|
|
Linux.)
|
|
|
|
If that does not work (probably because of an error in lilo.conf),
|
|
boot the machine using your rescue disk, restore \l
|
|
file:/etc/lilo.conf from backup and re-run lilo.
|
|
|
|
\i Testing: Here's a short program that opens the frame buffer and draws a
|
|
gradient-filled red square.
|
|
|
|
\code
|
|
#include <unistd.h>
|
|
#include <stdio.h>
|
|
#include <fcntl.h>
|
|
#include <linux/fb.h>
|
|
#include <sys/mman.h>
|
|
|
|
int main()
|
|
{
|
|
int fbfd = 0;
|
|
struct fb_var_screeninfo vinfo;
|
|
struct fb_fix_screeninfo finfo;
|
|
long int screensize = 0;
|
|
char *fbp = 0;
|
|
int x = 0, y = 0;
|
|
long int location = 0;
|
|
|
|
// Open the file for reading and writing
|
|
fbfd = open("/dev/fb0", O_RDWR);
|
|
if (!fbfd) {
|
|
printf("Error: cannot open framebuffer device.\n");
|
|
exit(1);
|
|
}
|
|
printf("The framebuffer device was opened successfully.\n");
|
|
|
|
// Get fixed screen information
|
|
if (ioctl(fbfd, FBIOGET_FSCREENINFO, &finfo)) {
|
|
printf("Error reading fixed information.\n");
|
|
exit(2);
|
|
}
|
|
|
|
// Get variable screen information
|
|
if (ioctl(fbfd, FBIOGET_VSCREENINFO, &vinfo)) {
|
|
printf("Error reading variable information.\n");
|
|
exit(3);
|
|
}
|
|
|
|
printf("%dx%d, %dbpp\n", vinfo.xres, vinfo.yres, vinfo.bits_per_pixel );
|
|
|
|
// Figure out the size of the screen in bytes
|
|
screensize = vinfo.xres * vinfo.yres * vinfo.bits_per_pixel / 8;
|
|
|
|
// Map the device to memory
|
|
fbp = (char *)mmap(0, screensize, PROT_READ | PROT_WRITE, MAP_SHARED,
|
|
fbfd, 0);
|
|
if ((int)fbp == -1) {
|
|
printf("Error: failed to map framebuffer device to memory.\n");
|
|
exit(4);
|
|
}
|
|
printf("The framebuffer device was mapped to memory successfully.\n");
|
|
|
|
x = 100; y = 100; // Where we are going to put the pixel
|
|
|
|
// Figure out where in memory to put the pixel
|
|
for ( y = 100; y < 300; y++ )
|
|
for ( x = 100; x < 300; x++ ) {
|
|
|
|
location = (x+vinfo.xoffset) * (vinfo.bits_per_pixel/8) +
|
|
(y+vinfo.yoffset) * finfo.line_length;
|
|
|
|
if ( vinfo.bits_per_pixel == 32 ) {
|
|
*(fbp + location) = 100; // Some blue
|
|
*(fbp + location + 1) = 15+(x-100)/2; // A little green
|
|
*(fbp + location + 2) = 200-(y-100)/5; // A lot of red
|
|
*(fbp + location + 3) = 0; // No transparency
|
|
} else { //assume 16bpp
|
|
int b = 10;
|
|
int g = (x-100)/6; // A little green
|
|
int r = 31-(y-100)/16; // A lot of red
|
|
unsigned short int t = r<<11 | g << 5 | b;
|
|
*((unsigned short int*)(fbp + location)) = t;
|
|
}
|
|
|
|
}
|
|
munmap(fbp, screensize);
|
|
close(fbfd);
|
|
return 0;
|
|
}
|
|
\endcode
|
|
\endlist
|
|
|
|
*/
|