xref: /openbmc/u-boot/arch/x86/cpu/qemu/dram.c (revision e246b728)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
4  */
5 
6 #include <common.h>
7 #include <asm/post.h>
8 #include <asm/arch/qemu.h>
9 
10 DECLARE_GLOBAL_DATA_PTR;
11 
12 int dram_init(void)
13 {
14 	u32 ram;
15 
16 	outb(HIGH_RAM_ADDR, CMOS_ADDR_PORT);
17 	ram = ((u32)inb(CMOS_DATA_PORT)) << 14;
18 	outb(LOW_RAM_ADDR, CMOS_ADDR_PORT);
19 	ram |= ((u32)inb(CMOS_DATA_PORT)) << 6;
20 	ram += 16 * 1024;
21 
22 	gd->ram_size = ram * 1024;
23 	post_code(POST_DRAM);
24 
25 	return 0;
26 }
27 
28 int dram_init_banksize(void)
29 {
30 	gd->bd->bi_dram[0].start = 0;
31 	gd->bd->bi_dram[0].size = gd->ram_size;
32 
33 	return 0;
34 }
35 
36 /*
37  * This function looks for the highest region of memory lower than 4GB which
38  * has enough space for U-Boot where U-Boot is aligned on a page boundary.
39  * It overrides the default implementation found elsewhere which simply
40  * picks the end of ram, wherever that may be. The location of the stack,
41  * the relocation address, and how far U-Boot is moved by relocation are
42  * set in the global data structure.
43  */
44 ulong board_get_usable_ram_top(ulong total_size)
45 {
46 	return gd->ram_size;
47 }
48