blob: 37dd8d43348ad46cc93e24bf88ed3561a4ecaca1 [file] [log] [blame]
Stephen Warrenc5f510f2016-07-18 17:01:51 -06001/*
2 * Copyright (c) 2016, NVIDIA CORPORATION.
3 *
4 * SPDX-License-Identifier: GPL-2.0+
5 */
6
7#include <common.h>
8#include <fdt_support.h>
9#include <fdtdec.h>
10#include <asm/arch/tegra.h>
11
12DECLARE_GLOBAL_DATA_PTR;
13
14extern unsigned long nvtboot_boot_x0;
15
16/*
17 * A parsed version of /memory/reg from the DTB that is passed to U-Boot in x0.
18 *
19 * We only support up to two banks since that's all the binary bootloader
20 * ever sets. We assume bank 0 is RAM below 4G and bank 1 is RAM above 4G.
21 * This is all a fairly safe assumption, since the L4T kernel makes the same
22 * assumptions, so the bootloader is unlikely to change.
23 *
24 * This is written to before relocation, and hence cannot be in .bss, since
25 * .bss overlaps the DTB that's appended to the U-Boot binary. The initializer
26 * forces this into .data and avoids this issue. This also has the nice side-
27 * effect of the content being valid after relocation.
28 */
29static struct {
30 u64 start;
31 u64 size;
32} ram_banks[2] = {{1}};
33
34int dram_init(void)
35{
36 unsigned int na, ns;
37 const void *nvtboot_blob = (void *)nvtboot_boot_x0;
38 int node, len, i;
39 const u32 *prop;
40
41 memset(ram_banks, 0, sizeof(ram_banks));
42
43 na = fdtdec_get_uint(nvtboot_blob, 0, "#address-cells", 2);
44 ns = fdtdec_get_uint(nvtboot_blob, 0, "#size-cells", 2);
45
46 node = fdt_path_offset(nvtboot_blob, "/memory");
47 if (node < 0) {
48 error("Can't find /memory node in nvtboot DTB");
49 hang();
50 }
51 prop = fdt_getprop(nvtboot_blob, node, "reg", &len);
52 if (!prop) {
53 error("Can't find /memory/reg property in nvtboot DTB");
54 hang();
55 }
56
57 len /= (na + ns);
58 if (len > ARRAY_SIZE(ram_banks))
59 len = ARRAY_SIZE(ram_banks);
60
61 gd->ram_size = 0;
62 for (i = 0; i < len; i++) {
63 ram_banks[i].start = of_read_number(prop, na);
64 prop += na;
65 ram_banks[i].size = of_read_number(prop, ns);
66 prop += ns;
67 gd->ram_size += ram_banks[i].size;
68 }
69
70 return 0;
71}
72
73extern unsigned long nvtboot_boot_x0;
74
75void dram_init_banksize(void)
76{
77 int i;
78
79 for (i = 0; i < 2; i++) {
80 gd->bd->bi_dram[i].start = ram_banks[i].start;
81 gd->bd->bi_dram[i].size = ram_banks[i].size;
82 }
83}
84
85ulong board_get_usable_ram_top(ulong total_size)
86{
87 return ram_banks[0].start + ram_banks[0].size;
88}