arch/x86/cpu/qemu/dram.c

   1 /*
   2  * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <asm/post.h>
   9 #include <asm/arch/qemu.h>
  10
  11 DECLARE_GLOBAL_DATA_PTR;
  12
  13 int dram_init(void)
  14 {
  15         u32 ram;
  16
  17         outb(HIGH_RAM_ADDR, CMOS_ADDR_PORT);
  18         ram = ((u32)inb(CMOS_DATA_PORT)) << 14;
  19         outb(LOW_RAM_ADDR, CMOS_ADDR_PORT);
  20         ram |= ((u32)inb(CMOS_DATA_PORT)) << 6;
  21         ram += 16 * 1024;
  22
  23         gd->ram_size = ram * 1024;
  24         post_code(POST_DRAM);
  25
  26         return 0;
  27 }
  28
  29 int dram_init_banksize(void)
  30 {
  31         gd->bd->bi_dram[0].start = 0;
  32         gd->bd->bi_dram[0].size = gd->ram_size;
  33
  34         return 0;
  35 }
  36
  37 /*
  38  * This function looks for the highest region of memory lower than 4GB which
  39  * has enough space for U-Boot where U-Boot is aligned on a page boundary.
  40  * It overrides the default implementation found elsewhere which simply
  41  * picks the end of ram, wherever that may be. The location of the stack,
  42  * the relocation address, and how far U-Boot is moved by relocation are
  43  * set in the global data structure.
  44  */
  45 ulong board_get_usable_ram_top(ulong total_size)
  46 {
  47         return gd->ram_size;
  48 }