xref: /openbmc/linux/drivers/video/fbdev/core/fbcon.h (revision c059ee9d)
1 /*
2  *  linux/drivers/video/console/fbcon.h -- Low level frame buffer based console driver
3  *
4  *	Copyright (C) 1997 Geert Uytterhoeven
5  *
6  *  This file is subject to the terms and conditions of the GNU General Public
7  *  License.  See the file COPYING in the main directory of this archive
8  *  for more details.
9  */
10 
11 #ifndef _VIDEO_FBCON_H
12 #define _VIDEO_FBCON_H
13 
14 #include <linux/types.h>
15 #include <linux/vt_buffer.h>
16 #include <linux/vt_kern.h>
17 #include <linux/workqueue.h>
18 
19 #include <asm/io.h>
20 
21    /*
22     *    This is the interface between the low-level console driver and the
23     *    low-level frame buffer device
24     */
25 
26 struct fbcon_display {
27     /* Filled in by the low-level console driver */
28     const u_char *fontdata;
29     int userfont;                   /* != 0 if fontdata kmalloc()ed */
30 #ifdef CONFIG_FRAMEBUFFER_CONSOLE_LEGACY_ACCELERATION
31     u_short scrollmode;             /* Scroll Method, use fb_scrollmode() */
32 #endif
33     u_short inverse;                /* != 0 text black on white as default */
34     short yscroll;                  /* Hardware scrolling */
35     int vrows;                      /* number of virtual rows */
36     int cursor_shape;
37     int con_rotate;
38     u32 xres_virtual;
39     u32 yres_virtual;
40     u32 height;
41     u32 width;
42     u32 bits_per_pixel;
43     u32 grayscale;
44     u32 nonstd;
45     u32 accel_flags;
46     u32 rotate;
47     struct fb_bitfield red;
48     struct fb_bitfield green;
49     struct fb_bitfield blue;
50     struct fb_bitfield transp;
51     const struct fb_videomode *mode;
52 };
53 
54 struct fbcon_ops {
55 	void (*bmove)(struct vc_data *vc, struct fb_info *info, int sy,
56 		      int sx, int dy, int dx, int height, int width);
57 	void (*clear)(struct vc_data *vc, struct fb_info *info, int sy,
58 		      int sx, int height, int width);
59 	void (*putcs)(struct vc_data *vc, struct fb_info *info,
60 		      const unsigned short *s, int count, int yy, int xx,
61 		      int fg, int bg);
62 	void (*clear_margins)(struct vc_data *vc, struct fb_info *info,
63 			      int color, int bottom_only);
64 	void (*cursor)(struct vc_data *vc, struct fb_info *info, int mode,
65 		       int fg, int bg);
66 	int  (*update_start)(struct fb_info *info);
67 	int  (*rotate_font)(struct fb_info *info, struct vc_data *vc);
68 	struct fb_var_screeninfo var;  /* copy of the current fb_var_screeninfo */
69 	struct delayed_work cursor_work; /* Cursor timer */
70 	struct fb_cursor cursor_state;
71 	struct fbcon_display *p;
72 	struct fb_info *info;
73         int    currcon;	                /* Current VC. */
74 	int    cur_blink_jiffies;
75 	int    cursor_flash;
76 	int    cursor_reset;
77 	int    blank_state;
78 	int    graphics;
79 	int    save_graphics; /* for debug enter/leave */
80 	bool   initialized;
81 	int    rotate;
82 	int    cur_rotate;
83 	char  *cursor_data;
84 	u8    *fontbuffer;
85 	u8    *fontdata;
86 	u8    *cursor_src;
87 	u32    cursor_size;
88 	u32    fd_size;
89 };
90     /*
91      *  Attribute Decoding
92      */
93 
94 /* Color */
95 #define attr_fgcol(fgshift,s)    \
96 	(((s) >> (fgshift)) & 0x0f)
97 #define attr_bgcol(bgshift,s)    \
98 	(((s) >> (bgshift)) & 0x0f)
99 
100 /* Monochrome */
101 #define attr_bold(s) \
102 	((s) & 0x200)
103 #define attr_reverse(s) \
104 	((s) & 0x800)
105 #define attr_underline(s) \
106 	((s) & 0x400)
107 #define attr_blink(s) \
108 	((s) & 0x8000)
109 
110 
111 static inline int mono_col(const struct fb_info *info)
112 {
113 	__u32 max_len;
114 	max_len = max(info->var.green.length, info->var.red.length);
115 	max_len = max(info->var.blue.length, max_len);
116 	return (~(0xfff << max_len)) & 0xff;
117 }
118 
119 static inline int attr_col_ec(int shift, struct vc_data *vc,
120 			      struct fb_info *info, int is_fg)
121 {
122 	int is_mono01;
123 	int col;
124 	int fg;
125 	int bg;
126 
127 	if (!vc)
128 		return 0;
129 
130 	if (vc->vc_can_do_color)
131 		return is_fg ? attr_fgcol(shift,vc->vc_video_erase_char)
132 			: attr_bgcol(shift,vc->vc_video_erase_char);
133 
134 	if (!info)
135 		return 0;
136 
137 	col = mono_col(info);
138 	is_mono01 = info->fix.visual == FB_VISUAL_MONO01;
139 
140 	if (attr_reverse(vc->vc_video_erase_char)) {
141 		fg = is_mono01 ? col : 0;
142 		bg = is_mono01 ? 0 : col;
143 	}
144 	else {
145 		fg = is_mono01 ? 0 : col;
146 		bg = is_mono01 ? col : 0;
147 	}
148 
149 	return is_fg ? fg : bg;
150 }
151 
152 #define attr_bgcol_ec(bgshift, vc, info) attr_col_ec(bgshift, vc, info, 0)
153 #define attr_fgcol_ec(fgshift, vc, info) attr_col_ec(fgshift, vc, info, 1)
154 
155     /*
156      *  Scroll Method
157      */
158 
159 /* There are several methods fbcon can use to move text around the screen:
160  *
161  *                     Operation   Pan    Wrap
162  *---------------------------------------------
163  * SCROLL_MOVE         copyarea    No     No
164  * SCROLL_PAN_MOVE     copyarea    Yes    No
165  * SCROLL_WRAP_MOVE    copyarea    No     Yes
166  * SCROLL_REDRAW       imageblit   No     No
167  * SCROLL_PAN_REDRAW   imageblit   Yes    No
168  * SCROLL_WRAP_REDRAW  imageblit   No     Yes
169  *
170  * (SCROLL_WRAP_REDRAW is not implemented yet)
171  *
172  * In general, fbcon will choose the best scrolling
173  * method based on the rule below:
174  *
175  * Pan/Wrap > accel imageblit > accel copyarea >
176  * soft imageblit > (soft copyarea)
177  *
178  * Exception to the rule: Pan + accel copyarea is
179  * preferred over Pan + accel imageblit.
180  *
181  * The above is typical for PCI/AGP cards. Unless
182  * overridden, fbcon will never use soft copyarea.
183  *
184  * If you need to override the above rule, set the
185  * appropriate flags in fb_info->flags.  For example,
186  * to prefer copyarea over imageblit, set
187  * FBINFO_READS_FAST.
188  *
189  * Other notes:
190  * + use the hardware engine to move the text
191  *    (hw-accelerated copyarea() and fillrect())
192  * + use hardware-supported panning on a large virtual screen
193  * + amifb can not only pan, but also wrap the display by N lines
194  *    (i.e. visible line i = physical line (i+N) % yres).
195  * + read what's already rendered on the screen and
196  *     write it in a different place (this is cfb_copyarea())
197  * + re-render the text to the screen
198  *
199  * Whether to use wrapping or panning can only be figured out at
200  * runtime (when we know whether our font height is a multiple
201  * of the pan/wrap step)
202  *
203  */
204 
205 #define SCROLL_MOVE	   0x001
206 #define SCROLL_PAN_MOVE	   0x002
207 #define SCROLL_WRAP_MOVE   0x003
208 #define SCROLL_REDRAW	   0x004
209 #define SCROLL_PAN_REDRAW  0x005
210 
211 static inline u_short fb_scrollmode(struct fbcon_display *fb)
212 {
213 #ifdef CONFIG_FRAMEBUFFER_CONSOLE_LEGACY_ACCELERATION
214 	return fb->scrollmode;
215 #else
216 	/* hardcoded to SCROLL_REDRAW if acceleration was disabled. */
217 	return SCROLL_REDRAW;
218 #endif
219 }
220 
221 
222 #ifdef CONFIG_FB_TILEBLITTING
223 extern void fbcon_set_tileops(struct vc_data *vc, struct fb_info *info);
224 #endif
225 extern void fbcon_set_bitops(struct fbcon_ops *ops);
226 extern int  soft_cursor(struct fb_info *info, struct fb_cursor *cursor);
227 
228 #define FBCON_ATTRIBUTE_UNDERLINE 1
229 #define FBCON_ATTRIBUTE_REVERSE   2
230 #define FBCON_ATTRIBUTE_BOLD      4
231 
232 static inline int real_y(struct fbcon_display *p, int ypos)
233 {
234 	int rows = p->vrows;
235 
236 	ypos += p->yscroll;
237 	return ypos < rows ? ypos : ypos - rows;
238 }
239 
240 
241 static inline int get_attribute(struct fb_info *info, u16 c)
242 {
243 	int attribute = 0;
244 
245 	if (fb_get_color_depth(&info->var, &info->fix) == 1) {
246 		if (attr_underline(c))
247 			attribute |= FBCON_ATTRIBUTE_UNDERLINE;
248 		if (attr_reverse(c))
249 			attribute |= FBCON_ATTRIBUTE_REVERSE;
250 		if (attr_bold(c))
251 			attribute |= FBCON_ATTRIBUTE_BOLD;
252 	}
253 
254 	return attribute;
255 }
256 
257 #define FBCON_SWAP(i,r,v) ({ \
258         typeof(r) _r = (r);  \
259         typeof(v) _v = (v);  \
260         (void) (&_r == &_v); \
261         (i == FB_ROTATE_UR || i == FB_ROTATE_UD) ? _r : _v; })
262 
263 #ifdef CONFIG_FRAMEBUFFER_CONSOLE_ROTATION
264 extern void fbcon_set_rotate(struct fbcon_ops *ops);
265 #else
266 #define fbcon_set_rotate(x) do {} while(0)
267 #endif /* CONFIG_FRAMEBUFFER_CONSOLE_ROTATION */
268 
269 #endif /* _VIDEO_FBCON_H */
270