fbdev: crash on single buffering
[libpicofe.git] / linux / fbdev.c
index 6ad1d4e..afd5531 100644 (file)
@@ -1,4 +1,15 @@
+/*
+ * (C) GraÅžvydas "notaz" Ignotas, 2009-2010
+ *
+ * This work is licensed under the terms of any of these licenses
+ * (at your option):
+ *  - GNU GPL, version 2 or later.
+ *  - GNU LGPL, version 2.1 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <linux/fb.h>
 #include <linux/matroxfb.h>
 
-#include "../common/emu.h"
 #include "fbdev.h"
 
-#define FBDEV_MAX_BUFFERS 3
+struct vout_fbdev {
+       int     fd;
+       void    *mem;
+       size_t  mem_size;
+       struct  fb_var_screeninfo fbvar_old;
+       struct  fb_var_screeninfo fbvar_new;
+       int     buffer_write;
+       int     fb_size;
+       int     buffer_count;
+       int     top_border, bottom_border;
+};
+
+void *vout_fbdev_flip(struct vout_fbdev *fbdev)
+{
+       int draw_buf;
+
+       if (fbdev->buffer_count < 2)
+               return fbdev->mem;
 
-static int fbdev = -1;
-static void *fbdev_mem = MAP_FAILED;
-static int fbdev_mem_size;
-static struct fb_var_screeninfo fbvar_old;
-static struct fb_var_screeninfo fbvar_new;
-static int fbdev_buffer_write;
+       draw_buf = fbdev->buffer_write;
+       fbdev->buffer_write++;
+       if (fbdev->buffer_write >= fbdev->buffer_count)
+               fbdev->buffer_write = 0;
 
-void *fbdev_buffers[FBDEV_MAX_BUFFERS];
-int fbdev_buffer_count;
+       fbdev->fbvar_new.yoffset = 
+               (fbdev->top_border + fbdev->fbvar_new.yres + fbdev->bottom_border) * draw_buf +
+               fbdev->top_border;
+
+       ioctl(fbdev->fd, FBIOPAN_DISPLAY, &fbdev->fbvar_new);
+
+       return (char *)fbdev->mem + fbdev->fb_size * fbdev->buffer_write;
+}
 
-void plat_video_flip(void)
+void vout_fbdev_wait_vsync(struct vout_fbdev *fbdev)
 {
-       int draw_buf;
+       int arg = 0;
+       ioctl(fbdev->fd, FBIO_WAITFORVSYNC, &arg);
+}
+
+/* it is recommended to call vout_fbdev_clear() before this */
+void *vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
+                     int left_border, int right_border, int top_border, int bottom_border, int buffer_cnt)
+{
+       int w_total = left_border + w + right_border;
+       int h_total = top_border + h + bottom_border;
+       size_t mem_size;
+       int ret;
+
+       // unblank to be sure the mode is really accepted
+       ioctl(fbdev->fd, FBIOBLANK, FB_BLANK_UNBLANK);
+
+       if (fbdev->fbvar_new.bits_per_pixel != bpp ||
+                       fbdev->fbvar_new.xres != w ||
+                       fbdev->fbvar_new.yres != h ||
+                       fbdev->fbvar_new.xres_virtual != w_total||
+                       fbdev->fbvar_new.yres_virtual < h_total ||
+                       fbdev->fbvar_new.xoffset != left_border ||
+                       fbdev->buffer_count != buffer_cnt)
+       {
+               if (fbdev->fbvar_new.bits_per_pixel != bpp ||
+                               w != fbdev->fbvar_new.xres || h != fbdev->fbvar_new.yres)
+                       printf(" switching to %dx%d@%d\n", w, h, bpp);
+
+               fbdev->fbvar_new.xres = w;
+               fbdev->fbvar_new.yres = h;
+               fbdev->fbvar_new.xres_virtual = w_total;
+               fbdev->fbvar_new.yres_virtual = h_total * buffer_cnt;
+               fbdev->fbvar_new.xoffset = left_border;
+               fbdev->fbvar_new.yoffset = top_border;
+               fbdev->fbvar_new.bits_per_pixel = bpp;
+               fbdev->fbvar_new.nonstd = 0; // can set YUV here on omapfb
+               fbdev->buffer_count = buffer_cnt;
+               fbdev->buffer_write = buffer_cnt > 1 ? 1 : 0;
+
+               // seems to help a bit to avoid glitches
+               vout_fbdev_wait_vsync(fbdev);
+
+               ret = ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_new);
+               if (ret == -1) {
+                       // retry with no multibuffering
+                       fbdev->fbvar_new.yres_virtual = h_total;
+                       ret = ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_new);
+                       if (ret == -1) {
+                               perror("FBIOPUT_VSCREENINFO ioctl");
+                               return NULL;
+                       }
+                       fbdev->buffer_count = 1;
+                       fbdev->buffer_write = 0;
+                       fprintf(stderr, "Warning: failed to increase virtual resolution, "
+                                       "multibuffering disabled\n");
+               }
 
-       if (fbdev_buffer_count < 2)
-               return;
+       }
 
-       draw_buf = fbdev_buffer_write;
-       fbdev_buffer_write++;
-       if (fbdev_buffer_write >= fbdev_buffer_count)
-               fbdev_buffer_write = 0;
+       fbdev->fb_size = w_total * h_total * bpp / 8;
+       fbdev->top_border = top_border;
+       fbdev->bottom_border = bottom_border;
 
-       fbvar_new.yoffset = fbvar_old.yres * draw_buf;
-       g_screen_ptr = fbdev_buffers[fbdev_buffer_write];
+       mem_size = fbdev->fb_size * fbdev->buffer_count;
+       if (fbdev->mem_size >= mem_size)
+               goto out;
+
+       if (fbdev->mem != NULL)
+               munmap(fbdev->mem, fbdev->mem_size);
+
+       fbdev->mem = mmap(0, mem_size, PROT_WRITE|PROT_READ, MAP_SHARED, fbdev->fd, 0);
+       if (fbdev->mem == MAP_FAILED && fbdev->buffer_count > 1) {
+               fprintf(stderr, "Warning: can't map %zd bytes, doublebuffering disabled\n", mem_size);
+               fbdev->buffer_count = 1;
+               fbdev->buffer_write = 0;
+               mem_size = fbdev->fb_size;
+               fbdev->mem = mmap(0, mem_size, PROT_WRITE|PROT_READ, MAP_SHARED, fbdev->fd, 0);
+       }
+       if (fbdev->mem == MAP_FAILED) {
+               fbdev->mem = NULL;
+               fbdev->mem_size = 0;
+               perror("mmap framebuffer");
+               return NULL;
+       }
+
+       fbdev->mem_size = mem_size;
+
+out:
+       return (char *)fbdev->mem + fbdev->fb_size * fbdev->buffer_write;
 }
 
-void plat_video_wait_vsync(void)
+void vout_fbdev_clear(struct vout_fbdev *fbdev)
 {
-       int arg = 0;
-       ioctl(fbdev, FBIO_WAITFORVSYNC, &arg);
+       memset(fbdev->mem, 0, fbdev->mem_size);
 }
 
-int vout_fbdev_init(int *w, int *h)
+void vout_fbdev_clear_lines(struct vout_fbdev *fbdev, int y, int count)
 {
-       static const char *fbdev_name = "/dev/fb0";
-       int i, ret;
+       int stride = fbdev->fbvar_new.xres_virtual * fbdev->fbvar_new.bits_per_pixel / 8;
+       int i;
+
+       if (y + count > fbdev->top_border + fbdev->fbvar_new.yres)
+               count = fbdev->top_border + fbdev->fbvar_new.yres - y;
 
-       fbdev = open(fbdev_name, O_RDWR);
-       if (fbdev == -1) {
+       if (y >= 0 && count > 0)
+               for (i = 0; i < fbdev->buffer_count; i++)
+                       memset((char *)fbdev->mem + fbdev->fb_size * i + y * stride, 0, stride * count);
+}
+
+int vout_fbdev_get_fd(struct vout_fbdev *fbdev)
+{
+       return fbdev->fd;
+}
+
+struct vout_fbdev *vout_fbdev_init(const char *fbdev_name, int *w, int *h, int bpp, int buffer_cnt)
+{
+       struct vout_fbdev *fbdev;
+       int req_w, req_h;
+       void *pret;
+       int ret;
+
+       fbdev = calloc(1, sizeof(*fbdev));
+       if (fbdev == NULL)
+               return NULL;
+
+       fbdev->fd = open(fbdev_name, O_RDWR);
+       if (fbdev->fd == -1) {
                fprintf(stderr, "%s: ", fbdev_name);
                perror("open");
-               return -1;
+               goto fail_open;
        }
 
-       ret = ioctl(fbdev, FBIOGET_VSCREENINFO, &fbvar_old);
+       ret = ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->fbvar_old);
        if (ret == -1) {
                perror("FBIOGET_VSCREENINFO ioctl");
                goto fail;
        }
 
-       fbvar_new = fbvar_old;
-       printf("%s: %ix%i@%d\n", fbdev_name, fbvar_old.xres, fbvar_old.yres, fbvar_old.bits_per_pixel);
-       *w = fbvar_old.xres;
-       *h = fbvar_old.yres;
-       fbdev_buffer_count = FBDEV_MAX_BUFFERS; // be optimistic
+       fbdev->fbvar_new = fbdev->fbvar_old;
 
-       if (fbvar_new.bits_per_pixel != 16) {
-               printf(" switching to 16bpp\n");
-               fbvar_new.bits_per_pixel = 16;
-               ret = ioctl(fbdev, FBIOPUT_VSCREENINFO, &fbvar_new);
-               if (ret == -1) {
-                       perror("FBIOPUT_VSCREENINFO ioctl");
-                       goto fail;
-               }
-       }
+       req_w = fbdev->fbvar_new.xres;
+       if (*w != 0)
+               req_w = *w;
+       req_h = fbdev->fbvar_new.yres;
+       if (*h != 0)
+               req_h = *h;
 
-       if (fbvar_new.yres_virtual < fbvar_old.yres * fbdev_buffer_count) {
-               fbvar_new.yres_virtual = fbvar_old.yres * fbdev_buffer_count;
-               ret = ioctl(fbdev, FBIOPUT_VSCREENINFO, &fbvar_new);
-               if (ret == -1) {
-                       fbdev_buffer_count = 1;
-                       fprintf(stderr, "Warning: failed to increase virtual resolution, "
-                                       "doublebuffering disabled\n");
-               }
-       }
-
-       fbdev_mem_size = *w * *h * 2 * fbdev_buffer_count;
-       fbdev_mem = mmap(0, fbdev_mem_size, PROT_WRITE|PROT_READ, MAP_SHARED, fbdev, 0);
-       if (fbdev_mem == MAP_FAILED && fbdev_buffer_count > 1) {
-               fbdev_mem_size = *w * *h * 2;
-               fbdev_buffer_count = 1;
-               fprintf(stderr, "Warning: can't map %d bytes, doublebuffering disabled\n", fbdev_mem_size);
-               fbdev_mem = mmap(0, fbdev_mem_size, PROT_WRITE|PROT_READ, MAP_SHARED, fbdev, 0);
-       }
-       if (fbdev_mem == MAP_FAILED) {
-               perror("mmap framebuffer");
+       pret = vout_fbdev_resize(fbdev, req_w, req_h, bpp, 0, 0, 0, 0, buffer_cnt);
+       if (pret == NULL)
                goto fail;
-       }
-       memset(fbdev_mem, 0, fbdev_mem_size);
-       for (i = 0; i < fbdev_buffer_count; i++)
-               fbdev_buffers[i] = (char *)fbdev_mem + i * *w * *h * 2;
-       g_screen_ptr = fbdev_buffers[0];
+
+       printf("%s: %ix%i@%d\n", fbdev_name, fbdev->fbvar_new.xres, fbdev->fbvar_new.yres,
+               fbdev->fbvar_new.bits_per_pixel);
+       *w = fbdev->fbvar_new.xres;
+       *h = fbdev->fbvar_new.yres;
+
+       memset(fbdev->mem, 0, fbdev->mem_size);
 
        // some checks
        ret = 0;
-       ret = ioctl(fbdev, FBIO_WAITFORVSYNC, &ret);
+       ret = ioctl(fbdev->fd, FBIO_WAITFORVSYNC, &ret);
        if (ret != 0)
                fprintf(stderr, "Warning: vsync doesn't seem to be supported\n");
 
-       if (fbdev_buffer_count > 1) {
-               fbdev_buffer_write = 0;
-               fbvar_new.yoffset = fbvar_old.yres * (fbdev_buffer_count - 1);
-               ret = ioctl(fbdev, FBIOPAN_DISPLAY, &fbvar_new);
+       if (fbdev->buffer_count > 1) {
+               fbdev->buffer_write = 0;
+               fbdev->fbvar_new.yoffset = fbdev->fbvar_new.yres * (fbdev->buffer_count - 1);
+               ret = ioctl(fbdev->fd, FBIOPAN_DISPLAY, &fbdev->fbvar_new);
                if (ret != 0) {
-                       fbdev_buffer_count = 1;
+                       fbdev->buffer_count = 1;
                        fprintf(stderr, "Warning: can't pan display, doublebuffering disabled\n");
                }
        }
 
        printf("fbdev initialized.\n");
-       return 0;
+       return fbdev;
 
 fail:
-       close(fbdev);
-       return -1;
+       close(fbdev->fd);
+fail_open:
+       free(fbdev);
+       return NULL;
 }
 
-void vout_fbdev_finish(void)
+void vout_fbdev_finish(struct vout_fbdev *fbdev)
 {
-       ioctl(fbdev, FBIOPUT_VSCREENINFO, &fbvar_old);
-       if (fbdev_mem != MAP_FAILED)
-               munmap(fbdev_mem, fbdev_mem_size);
-       if (fbdev >= 0)
-               close(fbdev);
-       fbdev_mem = NULL;
-       fbdev = -1;
+       ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_old);
+       if (fbdev->mem != MAP_FAILED)
+               munmap(fbdev->mem, fbdev->mem_size);
+       if (fbdev->fd >= 0)
+               close(fbdev->fd);
+       fbdev->mem = NULL;
+       fbdev->fd = -1;
+       free(fbdev);
 }
 
-#if 0
-void *g_screen_ptr;
-int main()
-{
-       int w, h;
-       vout_fbdev_init(&w, &h);
-       //while (1)
-       {
-               memset(g_screen_ptr, 0xff, fbdev_mem_size / 2);
-               plat_video_wait_vsync();
-               plat_video_flip();
-               memset(g_screen_ptr, 0x00, fbdev_mem_size / 2);
-               usleep(8000);
-//             plat_video_wait_vsync();
-               plat_video_flip();
-       }
-}
-#endif