video-vesa.c 6.6 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279
  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /* -*- linux-c -*- ------------------------------------------------------- *
  3. *
  4. * Copyright (C) 1991, 1992 Linus Torvalds
  5. * Copyright 2007 rPath, Inc. - All Rights Reserved
  6. * Copyright 2009 Intel Corporation; author H. Peter Anvin
  7. *
  8. * ----------------------------------------------------------------------- */
  9. /*
  10. * VESA text modes
  11. */
  12. #include "boot.h"
  13. #include "video.h"
  14. #include "vesa.h"
  15. #include "string.h"
  16. /* VESA information */
  17. static struct vesa_general_info vginfo;
  18. static struct vesa_mode_info vminfo;
  19. static __videocard video_vesa;
  20. #ifndef _WAKEUP
  21. static void vesa_store_mode_params_graphics(void);
  22. #else /* _WAKEUP */
  23. static inline void vesa_store_mode_params_graphics(void) {}
  24. #endif /* _WAKEUP */
  25. static int vesa_probe(void)
  26. {
  27. struct biosregs ireg, oreg;
  28. u16 mode;
  29. addr_t mode_ptr;
  30. struct mode_info *mi;
  31. int nmodes = 0;
  32. video_vesa.modes = GET_HEAP(struct mode_info, 0);
  33. initregs(&ireg);
  34. ireg.ax = 0x4f00;
  35. ireg.di = (size_t)&vginfo;
  36. intcall(0x10, &ireg, &oreg);
  37. if (oreg.ax != 0x004f ||
  38. vginfo.signature != VESA_MAGIC ||
  39. vginfo.version < 0x0102)
  40. return 0; /* Not present */
  41. set_fs(vginfo.video_mode_ptr.seg);
  42. mode_ptr = vginfo.video_mode_ptr.off;
  43. while ((mode = rdfs16(mode_ptr)) != 0xffff) {
  44. mode_ptr += 2;
  45. if (!heap_free(sizeof(struct mode_info)))
  46. break; /* Heap full, can't save mode info */
  47. if (mode & ~0x1ff)
  48. continue;
  49. memset(&vminfo, 0, sizeof(vminfo)); /* Just in case... */
  50. ireg.ax = 0x4f01;
  51. ireg.cx = mode;
  52. ireg.di = (size_t)&vminfo;
  53. intcall(0x10, &ireg, &oreg);
  54. if (oreg.ax != 0x004f)
  55. continue;
  56. if ((vminfo.mode_attr & 0x15) == 0x05) {
  57. /* Text Mode, TTY BIOS supported,
  58. supported by hardware */
  59. mi = GET_HEAP(struct mode_info, 1);
  60. mi->mode = mode + VIDEO_FIRST_VESA;
  61. mi->depth = 0; /* text */
  62. mi->x = vminfo.h_res;
  63. mi->y = vminfo.v_res;
  64. nmodes++;
  65. } else if ((vminfo.mode_attr & 0x99) == 0x99 &&
  66. (vminfo.memory_layout == 4 ||
  67. vminfo.memory_layout == 6) &&
  68. vminfo.memory_planes == 1) {
  69. #ifdef CONFIG_BOOT_VESA_SUPPORT
  70. /* Graphics mode, color, linear frame buffer
  71. supported. Only register the mode if
  72. if framebuffer is configured, however,
  73. otherwise the user will be left without a screen. */
  74. mi = GET_HEAP(struct mode_info, 1);
  75. mi->mode = mode + VIDEO_FIRST_VESA;
  76. mi->depth = vminfo.bpp;
  77. mi->x = vminfo.h_res;
  78. mi->y = vminfo.v_res;
  79. nmodes++;
  80. #endif
  81. }
  82. }
  83. return nmodes;
  84. }
  85. static int vesa_set_mode(struct mode_info *mode)
  86. {
  87. struct biosregs ireg, oreg;
  88. int is_graphic;
  89. u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
  90. memset(&vminfo, 0, sizeof(vminfo)); /* Just in case... */
  91. initregs(&ireg);
  92. ireg.ax = 0x4f01;
  93. ireg.cx = vesa_mode;
  94. ireg.di = (size_t)&vminfo;
  95. intcall(0x10, &ireg, &oreg);
  96. if (oreg.ax != 0x004f)
  97. return -1;
  98. if ((vminfo.mode_attr & 0x15) == 0x05) {
  99. /* It's a supported text mode */
  100. is_graphic = 0;
  101. #ifdef CONFIG_BOOT_VESA_SUPPORT
  102. } else if ((vminfo.mode_attr & 0x99) == 0x99) {
  103. /* It's a graphics mode with linear frame buffer */
  104. is_graphic = 1;
  105. vesa_mode |= 0x4000; /* Request linear frame buffer */
  106. #endif
  107. } else {
  108. return -1; /* Invalid mode */
  109. }
  110. initregs(&ireg);
  111. ireg.ax = 0x4f02;
  112. ireg.bx = vesa_mode;
  113. intcall(0x10, &ireg, &oreg);
  114. if (oreg.ax != 0x004f)
  115. return -1;
  116. graphic_mode = is_graphic;
  117. if (!is_graphic) {
  118. /* Text mode */
  119. force_x = mode->x;
  120. force_y = mode->y;
  121. do_restore = 1;
  122. } else {
  123. /* Graphics mode */
  124. vesa_store_mode_params_graphics();
  125. }
  126. return 0;
  127. }
  128. #ifndef _WAKEUP
  129. /* Switch DAC to 8-bit mode */
  130. static void vesa_dac_set_8bits(void)
  131. {
  132. struct biosregs ireg, oreg;
  133. u8 dac_size = 6;
  134. /* If possible, switch the DAC to 8-bit mode */
  135. if (vginfo.capabilities & 1) {
  136. initregs(&ireg);
  137. ireg.ax = 0x4f08;
  138. ireg.bh = 0x08;
  139. intcall(0x10, &ireg, &oreg);
  140. if (oreg.ax == 0x004f)
  141. dac_size = oreg.bh;
  142. }
  143. /* Set the color sizes to the DAC size, and offsets to 0 */
  144. boot_params.screen_info.red_size = dac_size;
  145. boot_params.screen_info.green_size = dac_size;
  146. boot_params.screen_info.blue_size = dac_size;
  147. boot_params.screen_info.rsvd_size = dac_size;
  148. boot_params.screen_info.red_pos = 0;
  149. boot_params.screen_info.green_pos = 0;
  150. boot_params.screen_info.blue_pos = 0;
  151. boot_params.screen_info.rsvd_pos = 0;
  152. }
  153. /* Save the VESA protected mode info */
  154. static void vesa_store_pm_info(void)
  155. {
  156. struct biosregs ireg, oreg;
  157. initregs(&ireg);
  158. ireg.ax = 0x4f0a;
  159. intcall(0x10, &ireg, &oreg);
  160. if (oreg.ax != 0x004f)
  161. return;
  162. boot_params.screen_info.vesapm_seg = oreg.es;
  163. boot_params.screen_info.vesapm_off = oreg.di;
  164. }
  165. /*
  166. * Save video mode parameters for graphics mode
  167. */
  168. static void vesa_store_mode_params_graphics(void)
  169. {
  170. /* Tell the kernel we're in VESA graphics mode */
  171. boot_params.screen_info.orig_video_isVGA = VIDEO_TYPE_VLFB;
  172. /* Mode parameters */
  173. boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
  174. boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
  175. boot_params.screen_info.lfb_width = vminfo.h_res;
  176. boot_params.screen_info.lfb_height = vminfo.v_res;
  177. boot_params.screen_info.lfb_depth = vminfo.bpp;
  178. boot_params.screen_info.pages = vminfo.image_planes;
  179. boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
  180. memcpy(&boot_params.screen_info.red_size,
  181. &vminfo.rmask, 8);
  182. /* General parameters */
  183. boot_params.screen_info.lfb_size = vginfo.total_memory;
  184. if (vminfo.bpp <= 8)
  185. vesa_dac_set_8bits();
  186. vesa_store_pm_info();
  187. }
  188. /*
  189. * Save EDID information for the kernel; this is invoked, separately,
  190. * after mode-setting.
  191. */
  192. void vesa_store_edid(void)
  193. {
  194. #ifdef CONFIG_FIRMWARE_EDID
  195. struct biosregs ireg, oreg;
  196. /* Apparently used as a nonsense token... */
  197. memset(&boot_params.edid_info, 0x13, sizeof(boot_params.edid_info));
  198. if (vginfo.version < 0x0200)
  199. return; /* EDID requires VBE 2.0+ */
  200. initregs(&ireg);
  201. ireg.ax = 0x4f15; /* VBE DDC */
  202. /* ireg.bx = 0x0000; */ /* Report DDC capabilities */
  203. /* ireg.cx = 0; */ /* Controller 0 */
  204. ireg.es = 0; /* ES:DI must be 0 by spec */
  205. intcall(0x10, &ireg, &oreg);
  206. if (oreg.ax != 0x004f)
  207. return; /* No EDID */
  208. /* BH = time in seconds to transfer EDD information */
  209. /* BL = DDC level supported */
  210. ireg.ax = 0x4f15; /* VBE DDC */
  211. ireg.bx = 0x0001; /* Read EDID */
  212. /* ireg.cx = 0; */ /* Controller 0 */
  213. /* ireg.dx = 0; */ /* EDID block number */
  214. ireg.es = ds();
  215. ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
  216. intcall(0x10, &ireg, &oreg);
  217. #endif /* CONFIG_FIRMWARE_EDID */
  218. }
  219. #endif /* not _WAKEUP */
  220. static __videocard video_vesa =
  221. {
  222. .card_name = "VESA",
  223. .probe = vesa_probe,
  224. .set_mode = vesa_set_mode,
  225. .xmode_first = VIDEO_FIRST_VESA,
  226. .xmode_n = 0x200,
  227. };