board.c 16 KB

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  1. /*
  2. * (C) Copyright 2003
  3. * Josef Baumgartner <josef.baumgartner@telex.de>
  4. *
  5. * (C) Copyright 2000-2002
  6. * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  7. *
  8. * See file CREDITS for list of people who contributed to this
  9. * project.
  10. *
  11. * This program is free software; you can redistribute it and/or
  12. * modify it under the terms of the GNU General Public License as
  13. * published by the Free Software Foundation; either version 2 of
  14. * the License, or (at your option) any later version.
  15. *
  16. * This program is distributed in the hope that it will be useful,
  17. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19. * GNU General Public License for more details.
  20. *
  21. * You should have received a copy of the GNU General Public License
  22. * along with this program; if not, write to the Free Software
  23. * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  24. * MA 02111-1307 USA
  25. */
  26. #include <common.h>
  27. #include <watchdog.h>
  28. #include <command.h>
  29. #include <malloc.h>
  30. #include <stdio_dev.h>
  31. #include <linux/compiler.h>
  32. #include <asm/immap.h>
  33. #if defined(CONFIG_CMD_IDE)
  34. #include <ide.h>
  35. #endif
  36. #if defined(CONFIG_CMD_SCSI)
  37. #include <scsi.h>
  38. #endif
  39. #if defined(CONFIG_CMD_KGDB)
  40. #include <kgdb.h>
  41. #endif
  42. #ifdef CONFIG_STATUS_LED
  43. #include <status_led.h>
  44. #endif
  45. #include <net.h>
  46. #include <serial.h>
  47. #if defined(CONFIG_CMD_BEDBUG)
  48. #include <cmd_bedbug.h>
  49. #endif
  50. #ifdef CONFIG_SYS_ALLOC_DPRAM
  51. #include <commproc.h>
  52. #endif
  53. #include <version.h>
  54. #if defined(CONFIG_HARD_I2C) || \
  55. defined(CONFIG_SOFT_I2C)
  56. #include <i2c.h>
  57. #endif
  58. #ifdef CONFIG_CMD_SPI
  59. #include <spi.h>
  60. #endif
  61. #ifdef CONFIG_BITBANGMII
  62. #include <miiphy.h>
  63. #endif
  64. #include <nand.h>
  65. DECLARE_GLOBAL_DATA_PTR;
  66. static char *failed = "*** failed ***\n";
  67. #include <environment.h>
  68. extern ulong __init_end;
  69. extern ulong __bss_end__;
  70. #if defined(CONFIG_WATCHDOG)
  71. # define INIT_FUNC_WATCHDOG_INIT watchdog_init,
  72. # define WATCHDOG_DISABLE watchdog_disable
  73. extern int watchdog_init(void);
  74. extern int watchdog_disable(void);
  75. #else
  76. # define INIT_FUNC_WATCHDOG_INIT /* undef */
  77. # define WATCHDOG_DISABLE /* undef */
  78. #endif /* CONFIG_WATCHDOG */
  79. ulong monitor_flash_len;
  80. /************************************************************************
  81. * Utilities *
  82. ************************************************************************
  83. */
  84. /*
  85. * All attempts to come up with a "common" initialization sequence
  86. * that works for all boards and architectures failed: some of the
  87. * requirements are just _too_ different. To get rid of the resulting
  88. * mess of board dependend #ifdef'ed code we now make the whole
  89. * initialization sequence configurable to the user.
  90. *
  91. * The requirements for any new initalization function is simple: it
  92. * receives a pointer to the "global data" structure as it's only
  93. * argument, and returns an integer return code, where 0 means
  94. * "continue" and != 0 means "fatal error, hang the system".
  95. */
  96. typedef int (init_fnc_t) (void);
  97. /************************************************************************
  98. * Init Utilities
  99. ************************************************************************
  100. * Some of this code should be moved into the core functions,
  101. * but let's get it working (again) first...
  102. */
  103. static int init_baudrate (void)
  104. {
  105. gd->baudrate = getenv_ulong("baudrate", 10, CONFIG_BAUDRATE);
  106. return 0;
  107. }
  108. /***********************************************************************/
  109. static int init_func_ram (void)
  110. {
  111. int board_type = 0; /* use dummy arg */
  112. puts ("DRAM: ");
  113. if ((gd->ram_size = initdram (board_type)) > 0) {
  114. print_size (gd->ram_size, "\n");
  115. return (0);
  116. }
  117. puts (failed);
  118. return (1);
  119. }
  120. /***********************************************************************/
  121. #if defined(CONFIG_HARD_I2C) || defined(CONFIG_SOFT_I2C)
  122. static int init_func_i2c (void)
  123. {
  124. puts ("I2C: ");
  125. i2c_init (CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
  126. puts ("ready\n");
  127. return (0);
  128. }
  129. #endif
  130. #if defined(CONFIG_HARD_SPI)
  131. static int init_func_spi (void)
  132. {
  133. puts ("SPI: ");
  134. spi_init ();
  135. puts ("ready\n");
  136. return (0);
  137. }
  138. #endif
  139. /***********************************************************************/
  140. /************************************************************************
  141. * Initialization sequence *
  142. ************************************************************************
  143. */
  144. init_fnc_t *init_sequence[] = {
  145. get_clocks,
  146. env_init,
  147. init_baudrate,
  148. serial_init,
  149. console_init_f,
  150. display_options,
  151. checkcpu,
  152. checkboard,
  153. #if defined(CONFIG_HARD_I2C) || defined(CONFIG_SOFT_I2C)
  154. init_func_i2c,
  155. #endif
  156. #if defined(CONFIG_HARD_SPI)
  157. init_func_spi,
  158. #endif
  159. init_func_ram,
  160. #if defined(CONFIG_SYS_DRAM_TEST)
  161. testdram,
  162. #endif /* CONFIG_SYS_DRAM_TEST */
  163. INIT_FUNC_WATCHDOG_INIT
  164. NULL, /* Terminate this list */
  165. };
  166. /************************************************************************
  167. *
  168. * This is the first part of the initialization sequence that is
  169. * implemented in C, but still running from ROM.
  170. *
  171. * The main purpose is to provide a (serial) console interface as
  172. * soon as possible (so we can see any error messages), and to
  173. * initialize the RAM so that we can relocate the monitor code to
  174. * RAM.
  175. *
  176. * Be aware of the restrictions: global data is read-only, BSS is not
  177. * initialized, and stack space is limited to a few kB.
  178. *
  179. ************************************************************************
  180. */
  181. void
  182. board_init_f (ulong bootflag)
  183. {
  184. bd_t *bd;
  185. ulong len, addr, addr_sp;
  186. ulong *paddr;
  187. gd_t *id;
  188. init_fnc_t **init_fnc_ptr;
  189. #ifdef CONFIG_PRAM
  190. ulong reg;
  191. #endif
  192. /* Pointer is writable since we allocated a register for it */
  193. gd = (gd_t *) (CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_GBL_DATA_OFFSET);
  194. /* compiler optimization barrier needed for GCC >= 3.4 */
  195. __asm__ __volatile__("": : :"memory");
  196. /* Clear initial global data */
  197. memset ((void *) gd, 0, sizeof (gd_t));
  198. for (init_fnc_ptr = init_sequence; *init_fnc_ptr; ++init_fnc_ptr) {
  199. if ((*init_fnc_ptr)() != 0) {
  200. hang ();
  201. }
  202. }
  203. /*
  204. * Now that we have DRAM mapped and working, we can
  205. * relocate the code and continue running from DRAM.
  206. *
  207. * Reserve memory at end of RAM for (top down in that order):
  208. * - protected RAM
  209. * - LCD framebuffer
  210. * - monitor code
  211. * - board info struct
  212. */
  213. len = (ulong)&__bss_end__ - CONFIG_SYS_MONITOR_BASE;
  214. addr = CONFIG_SYS_SDRAM_BASE + gd->ram_size;
  215. #ifdef CONFIG_LOGBUFFER
  216. /* reserve kernel log buffer */
  217. addr -= (LOGBUFF_RESERVE);
  218. debug ("Reserving %dk for kernel logbuffer at %08lx\n", LOGBUFF_LEN, addr);
  219. #endif
  220. #ifdef CONFIG_PRAM
  221. /*
  222. * reserve protected RAM
  223. */
  224. reg = getenv_ulong("pram", 10, CONFIG_PRAM);
  225. addr -= (reg << 10); /* size is in kB */
  226. debug ("Reserving %ldk for protected RAM at %08lx\n", reg, addr);
  227. #endif /* CONFIG_PRAM */
  228. /* round down to next 4 kB limit */
  229. addr &= ~(4096 - 1);
  230. debug ("Top of RAM usable for U-Boot at: %08lx\n", addr);
  231. #ifdef CONFIG_LCD
  232. #ifdef CONFIG_FB_ADDR
  233. gd->fb_base = CONFIG_FB_ADDR;
  234. #else
  235. /* reserve memory for LCD display (always full pages) */
  236. addr = lcd_setmem (addr);
  237. gd->fb_base = addr;
  238. #endif /* CONFIG_FB_ADDR */
  239. #endif /* CONFIG_LCD */
  240. /*
  241. * reserve memory for U-Boot code, data & bss
  242. * round down to next 4 kB limit
  243. */
  244. addr -= len;
  245. addr &= ~(4096 - 1);
  246. debug ("Reserving %ldk for U-Boot at: %08lx\n", len >> 10, addr);
  247. /*
  248. * reserve memory for malloc() arena
  249. */
  250. addr_sp = addr - TOTAL_MALLOC_LEN;
  251. debug ("Reserving %dk for malloc() at: %08lx\n",
  252. TOTAL_MALLOC_LEN >> 10, addr_sp);
  253. /*
  254. * (permanently) allocate a Board Info struct
  255. * and a permanent copy of the "global" data
  256. */
  257. addr_sp -= sizeof (bd_t);
  258. bd = (bd_t *) addr_sp;
  259. gd->bd = bd;
  260. debug ("Reserving %zu Bytes for Board Info at: %08lx\n",
  261. sizeof (bd_t), addr_sp);
  262. addr_sp -= sizeof (gd_t);
  263. id = (gd_t *) addr_sp;
  264. debug ("Reserving %zu Bytes for Global Data at: %08lx\n",
  265. sizeof (gd_t), addr_sp);
  266. /* Reserve memory for boot params. */
  267. addr_sp -= CONFIG_SYS_BOOTPARAMS_LEN;
  268. bd->bi_boot_params = addr_sp;
  269. debug ("Reserving %dk for boot parameters at: %08lx\n",
  270. CONFIG_SYS_BOOTPARAMS_LEN >> 10, addr_sp);
  271. /*
  272. * Finally, we set up a new (bigger) stack.
  273. *
  274. * Leave some safety gap for SP, force alignment on 16 byte boundary
  275. * Clear initial stack frame
  276. */
  277. addr_sp -= 16;
  278. addr_sp &= ~0xF;
  279. paddr = (ulong *)addr_sp;
  280. *paddr-- = 0;
  281. *paddr-- = 0;
  282. addr_sp = (ulong)paddr;
  283. debug ("Stack Pointer at: %08lx\n", addr_sp);
  284. /*
  285. * Save local variables to board info struct
  286. */
  287. bd->bi_memstart = CONFIG_SYS_SDRAM_BASE; /* start of DRAM memory */
  288. bd->bi_memsize = gd->ram_size; /* size of DRAM memory in bytes */
  289. #ifdef CONFIG_SYS_INIT_RAM_ADDR
  290. bd->bi_sramstart = CONFIG_SYS_INIT_RAM_ADDR; /* start of SRAM memory */
  291. bd->bi_sramsize = CONFIG_SYS_INIT_RAM_SIZE; /* size of SRAM memory */
  292. #endif
  293. bd->bi_mbar_base = CONFIG_SYS_MBAR; /* base of internal registers */
  294. bd->bi_bootflags = bootflag; /* boot / reboot flag (for LynxOS) */
  295. WATCHDOG_RESET ();
  296. bd->bi_intfreq = gd->cpu_clk; /* Internal Freq, in Hz */
  297. bd->bi_busfreq = gd->bus_clk; /* Bus Freq, in Hz */
  298. #ifdef CONFIG_PCI
  299. bd->bi_pcifreq = gd->pci_clk; /* PCI Freq in Hz */
  300. #endif
  301. #ifdef CONFIG_EXTRA_CLOCK
  302. bd->bi_inpfreq = gd->inp_clk; /* input Freq in Hz */
  303. bd->bi_vcofreq = gd->vco_clk; /* vco Freq in Hz */
  304. bd->bi_flbfreq = gd->flb_clk; /* flexbus Freq in Hz */
  305. #endif
  306. bd->bi_baudrate = gd->baudrate; /* Console Baudrate */
  307. #ifdef CONFIG_SYS_EXTBDINFO
  308. strncpy (bd->bi_s_version, "1.2", sizeof (bd->bi_s_version));
  309. strncpy (bd->bi_r_version, U_BOOT_VERSION, sizeof (bd->bi_r_version));
  310. #endif
  311. WATCHDOG_RESET ();
  312. #ifdef CONFIG_POST
  313. post_bootmode_init();
  314. post_run (NULL, POST_ROM | post_bootmode_get(0));
  315. #endif
  316. WATCHDOG_RESET();
  317. memcpy (id, (void *)gd, sizeof (gd_t));
  318. debug ("Start relocate of code from %08x to %08lx\n", CONFIG_SYS_MONITOR_BASE, addr);
  319. relocate_code (addr_sp, id, addr);
  320. /* NOTREACHED - jump_to_ram() does not return */
  321. }
  322. /************************************************************************
  323. *
  324. * This is the next part if the initialization sequence: we are now
  325. * running from RAM and have a "normal" C environment, i. e. global
  326. * data can be written, BSS has been cleared, the stack size in not
  327. * that critical any more, etc.
  328. *
  329. ************************************************************************
  330. */
  331. void board_init_r (gd_t *id, ulong dest_addr)
  332. {
  333. char *s __maybe_unused;
  334. bd_t *bd;
  335. #ifndef CONFIG_ENV_IS_NOWHERE
  336. extern char * env_name_spec;
  337. #endif
  338. #ifndef CONFIG_SYS_NO_FLASH
  339. ulong flash_size;
  340. #endif
  341. gd = id; /* initialize RAM version of global data */
  342. bd = gd->bd;
  343. gd->flags |= GD_FLG_RELOC; /* tell others: relocation done */
  344. serial_initialize();
  345. debug ("Now running in RAM - U-Boot at: %08lx\n", dest_addr);
  346. WATCHDOG_RESET ();
  347. gd->reloc_off = dest_addr - CONFIG_SYS_MONITOR_BASE;
  348. monitor_flash_len = (ulong)&__init_end - dest_addr;
  349. #if defined(CONFIG_NEEDS_MANUAL_RELOC)
  350. /*
  351. * We have to relocate the command table manually
  352. */
  353. fixup_cmdtable(ll_entry_start(cmd_tbl_t, cmd),
  354. ll_entry_count(cmd_tbl_t, cmd));
  355. #endif /* defined(CONFIG_NEEDS_MANUAL_RELOC) */
  356. /* there are some other pointer constants we must deal with */
  357. #ifndef CONFIG_ENV_IS_NOWHERE
  358. env_name_spec += gd->reloc_off;
  359. #endif
  360. WATCHDOG_RESET ();
  361. #ifdef CONFIG_LOGBUFFER
  362. logbuff_init_ptrs ();
  363. #endif
  364. #ifdef CONFIG_POST
  365. post_output_backlog ();
  366. post_reloc ();
  367. #endif
  368. WATCHDOG_RESET();
  369. #if 0
  370. /* instruction cache enabled in cpu_init_f() for faster relocation */
  371. icache_enable (); /* it's time to enable the instruction cache */
  372. #endif
  373. /*
  374. * Setup trap handlers
  375. */
  376. trap_init (CONFIG_SYS_SDRAM_BASE);
  377. /* The Malloc area is immediately below the monitor copy in DRAM */
  378. mem_malloc_init (CONFIG_SYS_MONITOR_BASE + gd->reloc_off -
  379. TOTAL_MALLOC_LEN, TOTAL_MALLOC_LEN);
  380. malloc_bin_reloc ();
  381. #if !defined(CONFIG_SYS_NO_FLASH)
  382. puts ("Flash: ");
  383. if ((flash_size = flash_init ()) > 0) {
  384. # ifdef CONFIG_SYS_FLASH_CHECKSUM
  385. print_size (flash_size, "");
  386. /*
  387. * Compute and print flash CRC if flashchecksum is set to 'y'
  388. *
  389. * NOTE: Maybe we should add some WATCHDOG_RESET()? XXX
  390. */
  391. if (getenv_yesno("flashchecksum") == 1) {
  392. printf (" CRC: %08X",
  393. crc32 (0,
  394. (const unsigned char *) CONFIG_SYS_FLASH_BASE,
  395. flash_size)
  396. );
  397. }
  398. putc ('\n');
  399. # else /* !CONFIG_SYS_FLASH_CHECKSUM */
  400. print_size (flash_size, "\n");
  401. # endif /* CONFIG_SYS_FLASH_CHECKSUM */
  402. } else {
  403. puts (failed);
  404. hang ();
  405. }
  406. bd->bi_flashstart = CONFIG_SYS_FLASH_BASE; /* update start of FLASH memory */
  407. bd->bi_flashsize = flash_size; /* size of FLASH memory (final value) */
  408. bd->bi_flashoffset = 0;
  409. #else /* CONFIG_SYS_NO_FLASH */
  410. bd->bi_flashsize = 0;
  411. bd->bi_flashstart = 0;
  412. bd->bi_flashoffset = 0;
  413. #endif /* !CONFIG_SYS_NO_FLASH */
  414. WATCHDOG_RESET ();
  415. /* initialize higher level parts of CPU like time base and timers */
  416. cpu_init_r ();
  417. WATCHDOG_RESET ();
  418. #ifdef CONFIG_SPI
  419. # if !defined(CONFIG_ENV_IS_IN_EEPROM)
  420. spi_init_f ();
  421. # endif
  422. spi_init_r ();
  423. #endif
  424. /* relocate environment function pointers etc. */
  425. env_relocate ();
  426. WATCHDOG_RESET ();
  427. #if defined(CONFIG_PCI)
  428. /*
  429. * Do pci configuration
  430. */
  431. pci_init ();
  432. #endif
  433. /** leave this here (after malloc(), environment and PCI are working) **/
  434. /* Initialize stdio devices */
  435. stdio_init ();
  436. /* Initialize the jump table for applications */
  437. jumptable_init ();
  438. /* Initialize the console (after the relocation and devices init) */
  439. console_init_r ();
  440. #if defined(CONFIG_MISC_INIT_R)
  441. /* miscellaneous platform dependent initialisations */
  442. misc_init_r ();
  443. #endif
  444. #if defined(CONFIG_CMD_KGDB)
  445. WATCHDOG_RESET ();
  446. puts ("KGDB: ");
  447. kgdb_init ();
  448. #endif
  449. debug ("U-Boot relocated to %08lx\n", dest_addr);
  450. /*
  451. * Enable Interrupts
  452. */
  453. interrupt_init ();
  454. /* Must happen after interrupts are initialized since
  455. * an irq handler gets installed
  456. */
  457. timer_init();
  458. #ifdef CONFIG_STATUS_LED
  459. status_led_set (STATUS_LED_BOOT, STATUS_LED_BLINKING);
  460. #endif
  461. udelay (20);
  462. /* Insert function pointers now that we have relocated the code */
  463. /* Initialize from environment */
  464. load_addr = getenv_ulong("loadaddr", 16, load_addr);
  465. WATCHDOG_RESET ();
  466. #if defined(CONFIG_CMD_DOC)
  467. WATCHDOG_RESET ();
  468. puts ("DOC: ");
  469. doc_init ();
  470. #endif
  471. #if defined(CONFIG_CMD_NAND)
  472. WATCHDOG_RESET ();
  473. puts ("NAND: ");
  474. nand_init(); /* go init the NAND */
  475. #endif
  476. #ifdef CONFIG_BITBANGMII
  477. bb_miiphy_init();
  478. #endif
  479. #if defined(CONFIG_CMD_NET)
  480. WATCHDOG_RESET();
  481. #if defined(FEC_ENET)
  482. eth_init(bd);
  483. #endif
  484. puts ("Net: ");
  485. eth_initialize (bd);
  486. #endif
  487. #ifdef CONFIG_POST
  488. post_run (NULL, POST_RAM | post_bootmode_get(0));
  489. #endif
  490. #if defined(CONFIG_CMD_PCMCIA) \
  491. && !defined(CONFIG_CMD_IDE)
  492. WATCHDOG_RESET ();
  493. puts ("PCMCIA:");
  494. pcmcia_init ();
  495. #endif
  496. #if defined(CONFIG_CMD_IDE)
  497. WATCHDOG_RESET ();
  498. puts ("IDE: ");
  499. ide_init ();
  500. #endif
  501. #ifdef CONFIG_LAST_STAGE_INIT
  502. WATCHDOG_RESET ();
  503. /*
  504. * Some parts can be only initialized if all others (like
  505. * Interrupts) are up and running (i.e. the PC-style ISA
  506. * keyboard).
  507. */
  508. last_stage_init ();
  509. #endif
  510. #if defined(CONFIG_CMD_BEDBUG)
  511. WATCHDOG_RESET ();
  512. bedbug_init ();
  513. #endif
  514. #if defined(CONFIG_PRAM) || defined(CONFIG_LOGBUFFER)
  515. /*
  516. * Export available size of memory for Linux,
  517. * taking into account the protected RAM at top of memory
  518. */
  519. {
  520. ulong pram = 0;
  521. char memsz[32];
  522. #ifdef CONFIG_PRAM
  523. pram = getenv_ulong("pram", 10, CONFIG_PRAM);
  524. #endif
  525. #ifdef CONFIG_LOGBUFFER
  526. /* Also take the logbuffer into account (pram is in kB) */
  527. pram += (LOGBUFF_LEN+LOGBUFF_OVERHEAD)/1024;
  528. #endif
  529. sprintf (memsz, "%ldk", (bd->bi_memsize / 1024) - pram);
  530. setenv ("mem", memsz);
  531. }
  532. #endif
  533. #ifdef CONFIG_MODEM_SUPPORT
  534. {
  535. extern int do_mdm_init;
  536. do_mdm_init = gd->do_mdm_init;
  537. }
  538. #endif
  539. #ifdef CONFIG_WATCHDOG
  540. /* disable watchdog if environment is set */
  541. if ((s = getenv ("watchdog")) != NULL) {
  542. if (strncmp (s, "off", 3) == 0) {
  543. WATCHDOG_DISABLE ();
  544. }
  545. }
  546. #endif /* CONFIG_WATCHDOG*/
  547. /* Initialization complete - start the monitor */
  548. /* main_loop() can return to retry autoboot, if so just run it again. */
  549. for (;;) {
  550. WATCHDOG_RESET ();
  551. main_loop ();
  552. }
  553. /* NOTREACHED - no way out of command loop except booting */
  554. }
  555. void hang(void)
  556. {
  557. puts ("### ERROR ### Please RESET the board ###\n");
  558. for (;;);
  559. }