xref: /openbmc/u-boot/arch/x86/cpu/coreboot/sdram.c (revision bc2df1af)
1 /*
2  * Copyright (c) 2011 The Chromium OS Authors.
3  * (C) Copyright 2010,2011
4  * Graeme Russ, <graeme.russ@gmail.com>
5  *
6  * See file CREDITS for list of people who contributed to this
7  * project.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of
12  * the License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but without any warranty; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
22  * MA 02111-1307 USA
23  */
24 
25 #include <common.h>
26 #include <malloc.h>
27 #include <asm/e820.h>
28 #include <asm/u-boot-x86.h>
29 #include <asm/global_data.h>
30 #include <asm/processor.h>
31 #include <asm/arch/sysinfo.h>
32 #include <asm/arch/tables.h>
33 
34 DECLARE_GLOBAL_DATA_PTR;
35 
36 unsigned install_e820_map(unsigned max_entries, struct e820entry *entries)
37 {
38 	int i;
39 
40 	unsigned num_entries = min(lib_sysinfo.n_memranges, max_entries);
41 	if (num_entries < lib_sysinfo.n_memranges) {
42 		printf("Warning: Limiting e820 map to %d entries.\n",
43 			num_entries);
44 	}
45 	for (i = 0; i < num_entries; i++) {
46 		struct memrange *memrange = &lib_sysinfo.memrange[i];
47 
48 		entries[i].addr = memrange->base;
49 		entries[i].size = memrange->size;
50 		entries[i].type = memrange->type;
51 	}
52 	return num_entries;
53 }
54 
55 /*
56  * This function looks for the highest region of memory lower than 4GB which
57  * has enough space for U-Boot where U-Boot is aligned on a page boundary. It
58  * overrides the default implementation found elsewhere which simply picks the
59  * end of ram, wherever that may be. The location of the stack, the relocation
60  * address, and how far U-Boot is moved by relocation are set in the global
61  * data structure.
62  */
63 ulong board_get_usable_ram_top(ulong total_size)
64 {
65 	uintptr_t dest_addr = 0;
66 	int i;
67 
68 	for (i = 0; i < lib_sysinfo.n_memranges; i++) {
69 		struct memrange *memrange = &lib_sysinfo.memrange[i];
70 		/* Force U-Boot to relocate to a page aligned address. */
71 		uint64_t start = roundup(memrange->base, 1 << 12);
72 		uint64_t end = memrange->base + memrange->size;
73 
74 		/* Ignore non-memory regions. */
75 		if (memrange->type != CB_MEM_RAM)
76 			continue;
77 
78 		/* Filter memory over 4GB. */
79 		if (end > 0xffffffffULL)
80 			end = 0x100000000ULL;
81 		/* Skip this region if it's too small. */
82 		if (end - start < total_size)
83 			continue;
84 
85 		/* Use this address if it's the largest so far. */
86 		if (end > dest_addr)
87 			dest_addr = end;
88 	}
89 
90 	/* If no suitable area was found, return an error. */
91 	if (!dest_addr)
92 		panic("No available memory found for relocation");
93 
94 	return (ulong)dest_addr;
95 }
96 
97 int dram_init_f(void)
98 {
99 	int i;
100 	phys_size_t ram_size = 0;
101 
102 	for (i = 0; i < lib_sysinfo.n_memranges; i++) {
103 		struct memrange *memrange = &lib_sysinfo.memrange[i];
104 		unsigned long long end = memrange->base + memrange->size;
105 
106 		if (memrange->type == CB_MEM_RAM && end > ram_size)
107 			ram_size = end;
108 	}
109 	gd->ram_size = ram_size;
110 	if (ram_size == 0)
111 		return -1;
112 	return 0;
113 }
114 
115 int dram_init(void)
116 {
117 	int i, j;
118 
119 	if (CONFIG_NR_DRAM_BANKS) {
120 		for (i = 0, j = 0; i < lib_sysinfo.n_memranges; i++) {
121 			struct memrange *memrange = &lib_sysinfo.memrange[i];
122 
123 			if (memrange->type == CB_MEM_RAM) {
124 				gd->bd->bi_dram[j].start = memrange->base;
125 				gd->bd->bi_dram[j].size = memrange->size;
126 				j++;
127 				if (j >= CONFIG_NR_DRAM_BANKS)
128 					break;
129 			}
130 		}
131 	}
132 	return 0;
133 }
134