Files
multirom_m86/lib/framebuffer_generic.c
2016-12-18 14:13:41 +03:00

152 lines
4.2 KiB
C

/*
* This file is part of MultiROM.
*
* MultiROM is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* MultiROM is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with MultiROM. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <string.h>
#include <linux/fb.h>
#include "framebuffer.h"
#include "log.h"
#include "util.h"
// only double-buffering is implemented, this define is just
// for the code to know how many buffers we use
#define NUM_BUFFERS 2
unsigned int smem_len;
struct fb_generic_data {
px_type *mapped[NUM_BUFFERS];
int active_buff;
};
static int impl_open(struct framebuffer *fb)
{
fb->vi.bits_per_pixel = 32;
INFO("Pixel format: %dx%d @ %dbpp\n", fb->vi.xres, fb->vi.yres, fb->vi.bits_per_pixel);
fb->vi.vmode = FB_VMODE_NONINTERLACED;
fb->vi.activate = FB_ACTIVATE_NOW | FB_ACTIVATE_FORCE;
ioctl(fb->fd, FBIOPUT_VSCREENINFO, &fb->vi);
ioctl(fb->fd, FBIOGET_FSCREENINFO, &fb->fi);
ioctl(fb->fd, FBIOGET_VSCREENINFO, &fb->vi);
INFO("fb0 reports (possibly inaccurate):\n"
" vi.bits_per_pixel = %d\n"
" vi.red.offset = %3d .length = %3d\n"
" vi.green.offset = %3d .length = %3d\n"
" vi.blue.offset = %3d .length = %3d\n"
" vi.xres = %3d vi.yres = %3d fi.line_length = %3d\n",
fb->vi.bits_per_pixel,
fb->vi.red.offset, fb->vi.red.length,
fb->vi.green.offset, fb->vi.green.length,
fb->vi.blue.offset, fb->vi.blue.length, fb->vi.xres, fb->vi.yres, fb->fi.line_length);
smem_len = fb->vi.yres * fb->fi.line_length;
INFO("smem_len: %d\n",smem_len);
// mmap and memset to 0 before setting the vi to prevent screen flickering during init
px_type *mapped = mmap(0, smem_len, PROT_READ | PROT_WRITE, MAP_SHARED, fb->fd, 0);
if (mapped == MAP_FAILED)
return -1;
memset(mapped, 0, smem_len);
munmap(mapped, smem_len);
if (ioctl(fb->fd, FBIOPUT_VSCREENINFO, &fb->vi) < 0)
{
ERROR("failed to set fb0 vi info");
return -1;
}
if (ioctl(fb->fd, FBIOGET_FSCREENINFO, &fb->fi) < 0)
return -1;
mapped = mmap(0, smem_len, PROT_READ | PROT_WRITE, MAP_SHARED, fb->fd, 0);
if (mapped == MAP_FAILED)
return -1;
struct fb_generic_data *data = mzalloc(sizeof(struct fb_generic_data));
data->mapped[0] = mapped;
data->mapped[1] = (px_type*) calloc(fb->vi.yres * fb->fi.line_length, 1);
fb->impl_data = data;
#ifdef TW_SCREEN_BLANK_ON_BOOT
ioctl(fb->fd, FBIOBLANK, FB_BLANK_POWERDOWN);
ioctl(fb->fd, FBIOBLANK, FB_BLANK_UNBLANK);
#endif
return 0;
}
static void impl_close(struct framebuffer *fb)
{
struct fb_generic_data *data = fb->impl_data;
__u32 dummy = 0;
if(data)
{
memset(data->mapped[0], 0, smem_len);
ioctl(fb->fd, FBIOPAN_DISPLAY, &fb->vi);
munmap(data->mapped[0], smem_len);
munmap(data->mapped[1], smem_len);
free(data);
fb->impl_data = NULL;
}
}
static int impl_update(struct framebuffer *fb)
{
struct fb_generic_data *data = fb->impl_data;
__u32 dummy = 0;
ioctl(fb->fd, FBIO_WAITFORVSYNC, &dummy);
memcpy(data->mapped[0], data->mapped[1], fb->vi.yres * fb->fi.line_length);
ioctl(fb->fd, FBIOPAN_DISPLAY, &fb->vi);
return 0;
}
static void *impl_get_frame_dest(struct framebuffer *fb)
{
struct fb_generic_data *data = fb->impl_data;
return data->mapped[1];
}
const struct fb_impl fb_impl_generic = {
.name = "Generic",
.impl_id = FB_IMPL_GENERIC,
.open = impl_open,
.close = impl_close,
.update = impl_update,
.get_frame_dest = impl_get_frame_dest,
};