+ htotal = mode->xres + mode->right_margin + mode->hsync_len
+ + mode->left_margin;
+ vtotal = mode->yres + mode->lower_margin + mode->vsync_len
+ + mode->upper_margin;
+
+ if (mode->vmode & FB_VMODE_INTERLACED)
+ vtotal /= 2;
+
+ if (mode->vmode & FB_VMODE_DOUBLE)
+ vtotal *= 2;
+
+ hscan = (pixclock + htotal / 2) / htotal;
+ hscan = (hscan + 500) / 1000 * 1000;
+ hz = (hscan + vtotal / 2) / vtotal;