cpu.c 2.1 KB

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  1. /*
  2. * (C) Copyright 2002
  3. * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
  4. * Marius Groeger <mgroeger@sysgo.de>
  5. *
  6. * (C) Copyright 2002
  7. * Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
  8. *
  9. * See file CREDITS for list of people who contributed to this
  10. * project.
  11. *
  12. * This program is free software; you can redistribute it and/or
  13. * modify it under the terms of the GNU General Public License as
  14. * published by the Free Software Foundation; either version 2 of
  15. * the License, or (at your option) any later version.
  16. *
  17. * This program is distributed in the hope that it will be useful,
  18. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  20. * GNU General Public License for more details.
  21. *
  22. * You should have received a copy of the GNU General Public License
  23. * along with this program; if not, write to the Free Software
  24. * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  25. * MA 02111-1307 USA
  26. */
  27. /*
  28. * CPU specific code
  29. */
  30. #include <common.h>
  31. #include <command.h>
  32. #include <arm946es.h>
  33. #include <asm/system.h>
  34. #ifdef CONFIG_USE_IRQ
  35. DECLARE_GLOBAL_DATA_PTR;
  36. #endif
  37. static void cache_flush(void);
  38. int cpu_init (void)
  39. {
  40. /*
  41. * setup up stacks if necessary
  42. */
  43. #ifdef CONFIG_USE_IRQ
  44. IRQ_STACK_START = _armboot_start - CONFIG_SYS_MALLOC_LEN - CONFIG_SYS_GBL_DATA_SIZE - 4;
  45. FIQ_STACK_START = IRQ_STACK_START - CONFIG_STACKSIZE_IRQ;
  46. #endif
  47. return 0;
  48. }
  49. int cleanup_before_linux (void)
  50. {
  51. /*
  52. * this function is called just before we call linux
  53. * it prepares the processor for linux
  54. *
  55. * we turn off caches etc ...
  56. */
  57. disable_interrupts ();
  58. /* ARM926E-S needs the protection unit enabled for the icache to have
  59. * been enabled - left for possible later use
  60. * should turn off the protection unit as well....
  61. */
  62. /* turn off I/D-cache */
  63. icache_disable();
  64. dcache_disable();
  65. /* flush I/D-cache */
  66. cache_flush();
  67. return 0;
  68. }
  69. /* flush I/D-cache */
  70. static void cache_flush (void)
  71. {
  72. unsigned long i = 0;
  73. asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
  74. asm ("mcr p15, 0, %0, c7, c6, 0": :"r" (i));
  75. }