setup.c 1.5 KB

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  1. /*
  2. * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
  3. * Copyright (C) 2011, Maarten ter Huurne <maarten@treewalker.org>
  4. * JZ4740 setup code
  5. *
  6. * This program is free software; you can redistribute it and/or modify it
  7. * under the terms of the GNU General Public License as published by the
  8. * Free Software Foundation; either version 2 of the License, or (at your
  9. * option) any later version.
  10. *
  11. * You should have received a copy of the GNU General Public License along
  12. * with this program; if not, write to the Free Software Foundation, Inc.,
  13. * 675 Mass Ave, Cambridge, MA 02139, USA.
  14. *
  15. */
  16. #include <linux/init.h>
  17. #include <linux/io.h>
  18. #include <linux/kernel.h>
  19. #include <asm/bootinfo.h>
  20. #include <asm/mach-jz4740/base.h>
  21. #include "reset.h"
  22. #define JZ4740_EMC_SDRAM_CTRL 0x80
  23. static void __init jz4740_detect_mem(void)
  24. {
  25. void __iomem *jz_emc_base;
  26. u32 ctrl, bus, bank, rows, cols;
  27. phys_t size;
  28. jz_emc_base = ioremap(JZ4740_EMC_BASE_ADDR, 0x100);
  29. ctrl = readl(jz_emc_base + JZ4740_EMC_SDRAM_CTRL);
  30. bus = 2 - ((ctrl >> 31) & 1);
  31. bank = 1 + ((ctrl >> 19) & 1);
  32. cols = 8 + ((ctrl >> 26) & 7);
  33. rows = 11 + ((ctrl >> 20) & 3);
  34. printk(KERN_DEBUG
  35. "SDRAM preconfigured: bus:%u bank:%u rows:%u cols:%u\n",
  36. bus, bank, rows, cols);
  37. iounmap(jz_emc_base);
  38. size = 1 << (bus + bank + cols + rows);
  39. add_memory_region(0, size, BOOT_MEM_RAM);
  40. }
  41. void __init plat_mem_setup(void)
  42. {
  43. jz4740_reset_init();
  44. jz4740_detect_mem();
  45. }
  46. const char *get_system_type(void)
  47. {
  48. return "JZ4740";
  49. }