1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (c) 2016 Google, Inc
9 #include <video_console.h>
11 /* Functions needed by stb_truetype.h */
12 static int tt_floor(double val)
15 return (int)(val - 0.999);
20 static int tt_ceil(double val)
25 return (int)(val + 0.999);
28 static double frac(double val)
30 return val - tt_floor(val);
33 static double tt_fabs(double x)
35 return x < 0 ? -x : x;
39 * Simple square root algorithm. This is from:
40 * http://stackoverflow.com/questions/1623375/writing-your-own-square-root-function
41 * Written by Chihung Yu
42 * Creative Commons license
43 * http://creativecommons.org/licenses/by-sa/3.0/legalcode
44 * It has been modified to compile correctly, and for U-Boot style.
46 static double tt_sqrt(double value)
51 while (hi - lo > 0.00001) {
52 double mid = lo + (hi - lo) / 2;
54 if (mid * mid - value > 0.00001)
63 #define STBTT_ifloor tt_floor
64 #define STBTT_iceil tt_ceil
65 #define STBTT_fabs tt_fabs
66 #define STBTT_sqrt tt_sqrt
67 #define STBTT_malloc(size, u) ((void)(u), malloc(size))
68 #define STBTT_free(size, u) ((void)(u), free(size))
69 #define STBTT_assert(x)
70 #define STBTT_strlen(x) strlen(x)
71 #define STBTT_memcpy memcpy
72 #define STBTT_memset memset
74 #define STB_TRUETYPE_IMPLEMENTATION
75 #include "stb_truetype.h"
78 * struct pos_info - Records a cursor position
80 * @xpos_frac: Fractional X position in pixels (multiplied by VID_FRAC_DIV)
81 * @ypos: Y position (pixels from the top)
89 * Allow one for each character on the command line plus one for each newline.
90 * This is just an estimate, but it should not be exceeded.
92 #define POS_HISTORY_SIZE (CONFIG_SYS_CBSIZE * 11 / 10)
95 * struct console_tt_priv - Private data for this driver
97 * @font_size: Vertical font size in pixels
98 * @font_data: Pointer to TrueType font file contents
99 * @font: TrueType font information for the current font
100 * @pos: List of cursor positions for each character written. This is
101 * used to handle backspace. We clear the frame buffer between
102 * the last position and the current position, thus erasing the
103 * last character. We record enough characters to go back to the
104 * start of the current command line.
105 * @pos_ptr: Current position in the position history
106 * @baseline: Pixel offset of the font's baseline from the cursor position.
107 * This is the 'ascent' of the font, scaled to pixel coordinates.
108 * It measures the distance from the baseline to the top of the
110 * @scale: Scale of the font. This is calculated from the pixel height
111 * of the font. It is used by the STB library to generate images
112 * of the correct size.
114 struct console_tt_priv {
118 struct pos_info pos[POS_HISTORY_SIZE];
124 static int console_truetype_set_row(struct udevice *dev, uint row, int clr)
126 struct video_priv *vid_priv = dev_get_uclass_priv(dev->parent);
127 struct console_tt_priv *priv = dev_get_priv(dev);
129 int pixels = priv->font_size * vid_priv->line_length;
132 line = vid_priv->fb + row * priv->font_size * vid_priv->line_length;
133 switch (vid_priv->bpix) {
134 #ifdef CONFIG_VIDEO_BPP8
138 for (i = 0; i < pixels; i++)
143 #ifdef CONFIG_VIDEO_BPP16
145 uint16_t *dst = line;
147 for (i = 0; i < pixels; i++)
152 #ifdef CONFIG_VIDEO_BPP32
154 uint32_t *dst = line;
156 for (i = 0; i < pixels; i++)
168 static int console_truetype_move_rows(struct udevice *dev, uint rowdst,
169 uint rowsrc, uint count)
171 struct video_priv *vid_priv = dev_get_uclass_priv(dev->parent);
172 struct console_tt_priv *priv = dev_get_priv(dev);
177 dst = vid_priv->fb + rowdst * priv->font_size * vid_priv->line_length;
178 src = vid_priv->fb + rowsrc * priv->font_size * vid_priv->line_length;
179 memmove(dst, src, priv->font_size * vid_priv->line_length * count);
181 /* Scroll up our position history */
182 diff = (rowsrc - rowdst) * priv->font_size;
183 for (i = 0; i < priv->pos_ptr; i++)
184 priv->pos[i].ypos -= diff;
189 static int console_truetype_putc_xy(struct udevice *dev, uint x, uint y,
192 struct vidconsole_priv *vc_priv = dev_get_uclass_priv(dev);
193 struct udevice *vid = dev->parent;
194 struct video_priv *vid_priv = dev_get_uclass_priv(vid);
195 struct console_tt_priv *priv = dev_get_priv(dev);
196 stbtt_fontinfo *font = &priv->font;
197 int width, height, xoff, yoff;
198 double xpos, x_shift;
200 int width_frac, linenum;
201 struct pos_info *pos;
207 /* First get some basic metrics about this character */
208 stbtt_GetCodepointHMetrics(font, ch, &advance, &lsb);
211 * First out our current X position in fractional pixels. If we wrote
212 * a character previously, using kerning to fine-tune the position of
214 xpos = frac(VID_TO_PIXEL((double)x));
215 if (vc_priv->last_ch) {
216 xpos += priv->scale * stbtt_GetCodepointKernAdvance(font,
217 vc_priv->last_ch, ch);
221 * Figure out where the cursor will move to after this character, and
222 * abort if we are out of space on this line. Also calculate the
223 * effective width of this character, which will be our return value:
224 * it dictates how much the cursor will move forward on the line.
226 x_shift = xpos - (double)tt_floor(xpos);
227 xpos += advance * priv->scale;
228 width_frac = (int)VID_TO_POS(xpos);
229 if (x + width_frac >= vc_priv->xsize_frac)
232 /* Write the current cursor position into history */
233 if (priv->pos_ptr < POS_HISTORY_SIZE) {
234 pos = &priv->pos[priv->pos_ptr];
235 pos->xpos_frac = vc_priv->xcur_frac;
236 pos->ypos = vc_priv->ycur;
241 * Figure out how much past the start of a pixel we are, and pass this
242 * information into the render, which will return a 8-bit-per-pixel
243 * image of the character. For empty characters, like ' ', data will
246 data = stbtt_GetCodepointBitmapSubpixel(font, priv->scale, priv->scale,
247 x_shift, 0, ch, &width, &height,
252 /* Figure out where to write the character in the frame buffer */
254 line = vid_priv->fb + y * vid_priv->line_length +
255 VID_TO_PIXEL(x) * VNBYTES(vid_priv->bpix);
256 linenum = priv->baseline + yoff;
258 line += linenum * vid_priv->line_length;
261 * Write a row at a time, converting the 8bpp image into the colour
262 * depth of the display. We only expect white-on-black or the reverse
263 * so the code only handles this simple case.
265 for (row = 0; row < height; row++) {
266 switch (vid_priv->bpix) {
267 #ifdef CONFIG_VIDEO_BPP16
269 uint16_t *dst = (uint16_t *)line + xoff;
272 for (i = 0; i < width; i++) {
276 if (vid_priv->colour_bg)
281 if (vid_priv->colour_fg)
295 line += vid_priv->line_length;
303 * console_truetype_erase() - Erase a character
305 * This is used for backspace. We erase a square of the display within the
308 * @dev: Device to update
309 * @xstart: X start position in pixels from the left
310 * @ystart: Y start position in pixels from the top
311 * @xend: X end position in pixels from the left
312 * @yend: Y end position in pixels from the top
313 * @clr: Value to write
314 * @return 0 if OK, -ENOSYS if the display depth is not supported
316 static int console_truetype_erase(struct udevice *dev, int xstart, int ystart,
317 int xend, int yend, int clr)
319 struct video_priv *vid_priv = dev_get_uclass_priv(dev->parent);
321 int pixels = xend - xstart;
324 line = vid_priv->fb + ystart * vid_priv->line_length;
325 line += xstart * VNBYTES(vid_priv->bpix);
326 for (row = ystart; row < yend; row++) {
327 switch (vid_priv->bpix) {
328 #ifdef CONFIG_VIDEO_BPP8
332 for (i = 0; i < pixels; i++)
337 #ifdef CONFIG_VIDEO_BPP16
339 uint16_t *dst = line;
341 for (i = 0; i < pixels; i++)
346 #ifdef CONFIG_VIDEO_BPP32
348 uint32_t *dst = line;
350 for (i = 0; i < pixels; i++)
358 line += vid_priv->line_length;
365 * console_truetype_backspace() - Handle a backspace operation
367 * This clears the previous character so that the console looks as if it had
370 * @dev: Device to update
371 * @return 0 if OK, -ENOSYS if not supported
373 static int console_truetype_backspace(struct udevice *dev)
375 struct vidconsole_priv *vc_priv = dev_get_uclass_priv(dev);
376 struct console_tt_priv *priv = dev_get_priv(dev);
377 struct udevice *vid_dev = dev->parent;
378 struct video_priv *vid_priv = dev_get_uclass_priv(vid_dev);
379 struct pos_info *pos;
383 * This indicates a very strange error higher in the stack. The caller
384 * has sent out n character and n + 1 backspaces.
389 /* Pop the last cursor position off the stack */
390 pos = &priv->pos[--priv->pos_ptr];
393 * Figure out the end position for clearing. Normlly it is the current
394 * cursor position, but if we are clearing a character on the previous
395 * line, we clear from the end of the line.
397 if (pos->ypos == vc_priv->ycur)
398 xend = VID_TO_PIXEL(vc_priv->xcur_frac);
400 xend = vid_priv->xsize;
402 console_truetype_erase(dev, VID_TO_PIXEL(pos->xpos_frac), pos->ypos,
403 xend, pos->ypos + vc_priv->y_charsize,
404 vid_priv->colour_bg);
406 /* Move the cursor back to where it was when we pushed this record */
407 vc_priv->xcur_frac = pos->xpos_frac;
408 vc_priv->ycur = pos->ypos;
413 static int console_truetype_entry_start(struct udevice *dev)
415 struct console_tt_priv *priv = dev_get_priv(dev);
417 /* A new input line has start, so clear our history */
424 * Provides a list of fonts which can be obtained at run-time in U-Boot. These
425 * are compiled in by the Makefile.
427 * At present there is no mechanism to select a particular font - the first
428 * one found is the one that is used. But the build system and the code here
429 * supports multiple fonts, which may be useful for certain firmware screens.
437 #define FONT_DECL(_name) \
438 extern u8 __ttf_ ## _name ## _begin[]; \
439 extern u8 __ttf_ ## _name ## _end[];
441 #define FONT_ENTRY(_name) { \
443 .begin = __ttf_ ## _name ## _begin, \
444 .end = __ttf_ ## _name ## _end, \
447 FONT_DECL(nimbus_sans_l_regular);
448 FONT_DECL(ankacoder_c75_r);
449 FONT_DECL(rufscript010);
450 FONT_DECL(cantoraone_regular);
452 static struct font_info font_table[] = {
453 #ifdef CONFIG_CONSOLE_TRUETYPE_NIMBUS
454 FONT_ENTRY(nimbus_sans_l_regular),
456 #ifdef CONFIG_CONSOLE_TRUETYPE_ANKACODER
457 FONT_ENTRY(ankacoder_c75_r),
459 #ifdef CONFIG_CONSOLE_TRUETYPE_RUFSCRIPT
460 FONT_ENTRY(rufscript010),
462 #ifdef CONFIG_CONSOLE_TRUETYPE_CANTORAONE
463 FONT_ENTRY(cantoraone_regular),
468 #define FONT_BEGIN(name) __ttf_ ## name ## _begin
469 #define FONT_END(name) __ttf_ ## name ## _end
470 #define FONT_IS_VALID(name) (abs(FONT_END(name) - FONT_BEGIN) > 4)
473 * console_truetype_find_font() - Find a suitable font
475 * This searched for the first available font.
477 * @return pointer to the font, or NULL if none is found
479 static u8 *console_truetype_find_font(void)
481 struct font_info *tab;
483 for (tab = font_table; tab->begin; tab++) {
484 if (abs(tab->begin - tab->end) > 4) {
485 debug("%s: Font '%s', at %p, size %lx\n", __func__,
486 tab->name, tab->begin,
487 (ulong)(tab->end - tab->begin));
495 static int console_truetype_probe(struct udevice *dev)
497 struct vidconsole_priv *vc_priv = dev_get_uclass_priv(dev);
498 struct console_tt_priv *priv = dev_get_priv(dev);
499 struct udevice *vid_dev = dev->parent;
500 struct video_priv *vid_priv = dev_get_uclass_priv(vid_dev);
501 stbtt_fontinfo *font = &priv->font;
504 debug("%s: start\n", __func__);
505 if (vid_priv->font_size)
506 priv->font_size = vid_priv->font_size;
508 priv->font_size = CONFIG_CONSOLE_TRUETYPE_SIZE;
509 priv->font_data = console_truetype_find_font();
510 if (!priv->font_data) {
511 debug("%s: Could not find any fonts\n", __func__);
515 vc_priv->x_charsize = priv->font_size;
516 vc_priv->y_charsize = priv->font_size;
517 vc_priv->xstart_frac = VID_TO_POS(2);
518 vc_priv->cols = vid_priv->xsize / priv->font_size;
519 vc_priv->rows = vid_priv->ysize / priv->font_size;
520 vc_priv->tab_width_frac = VID_TO_POS(priv->font_size) * 8 / 2;
522 if (!stbtt_InitFont(font, priv->font_data, 0)) {
523 debug("%s: Font init failed\n", __func__);
527 /* Pre-calculate some things we will need regularly */
528 priv->scale = stbtt_ScaleForPixelHeight(font, priv->font_size);
529 stbtt_GetFontVMetrics(font, &ascent, 0, 0);
530 priv->baseline = (int)(ascent * priv->scale);
531 debug("%s: ready\n", __func__);
536 struct vidconsole_ops console_truetype_ops = {
537 .putc_xy = console_truetype_putc_xy,
538 .move_rows = console_truetype_move_rows,
539 .set_row = console_truetype_set_row,
540 .backspace = console_truetype_backspace,
541 .entry_start = console_truetype_entry_start,
544 U_BOOT_DRIVER(vidconsole_truetype) = {
545 .name = "vidconsole_tt",
546 .id = UCLASS_VIDEO_CONSOLE,
547 .ops = &console_truetype_ops,
548 .probe = console_truetype_probe,
549 .priv_auto_alloc_size = sizeof(struct console_tt_priv),