xref: /openbmc/u-boot/arch/x86/cpu/coreboot/sdram.c (revision 68fbc0e6)
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/sections.h>
32 #include <asm/arch/sysinfo.h>
33 #include <asm/arch/tables.h>
34 
35 DECLARE_GLOBAL_DATA_PTR;
36 
37 unsigned install_e820_map(unsigned max_entries, struct e820entry *entries)
38 {
39 	int i;
40 
41 	unsigned num_entries = min(lib_sysinfo.n_memranges, max_entries);
42 	if (num_entries < lib_sysinfo.n_memranges) {
43 		printf("Warning: Limiting e820 map to %d entries.\n",
44 			num_entries);
45 	}
46 	for (i = 0; i < num_entries; i++) {
47 		struct memrange *memrange = &lib_sysinfo.memrange[i];
48 
49 		entries[i].addr = memrange->base;
50 		entries[i].size = memrange->size;
51 		entries[i].type = memrange->type;
52 	}
53 	return num_entries;
54 }
55 
56 /*
57  * This function looks for the highest region of memory lower than 4GB which
58  * has enough space for U-Boot where U-Boot is aligned on a page boundary. It
59  * overrides the default implementation found elsewhere which simply picks the
60  * end of ram, wherever that may be. The location of the stack, the relocation
61  * address, and how far U-Boot is moved by relocation are set in the global
62  * data structure.
63  */
64 ulong board_get_usable_ram_top(ulong total_size)
65 {
66 	uintptr_t dest_addr = 0;
67 	int i;
68 
69 	for (i = 0; i < lib_sysinfo.n_memranges; i++) {
70 		struct memrange *memrange = &lib_sysinfo.memrange[i];
71 		/* Force U-Boot to relocate to a page aligned address. */
72 		uint64_t start = roundup(memrange->base, 1 << 12);
73 		uint64_t end = memrange->base + memrange->size;
74 
75 		/* Ignore non-memory regions. */
76 		if (memrange->type != CB_MEM_RAM)
77 			continue;
78 
79 		/* Filter memory over 4GB. */
80 		if (end > 0xffffffffULL)
81 			end = 0x100000000ULL;
82 		/* Skip this region if it's too small. */
83 		if (end - start < total_size)
84 			continue;
85 
86 		/* Use this address if it's the largest so far. */
87 		if (end > dest_addr)
88 			dest_addr = end;
89 	}
90 
91 	/* If no suitable area was found, return an error. */
92 	if (!dest_addr)
93 		panic("No available memory found for relocation");
94 
95 	return (ulong)dest_addr;
96 }
97 
98 int dram_init_f(void)
99 {
100 	int i;
101 	phys_size_t ram_size = 0;
102 
103 	for (i = 0; i < lib_sysinfo.n_memranges; i++) {
104 		struct memrange *memrange = &lib_sysinfo.memrange[i];
105 		unsigned long long end = memrange->base + memrange->size;
106 
107 		if (memrange->type == CB_MEM_RAM && end > ram_size)
108 			ram_size = end;
109 	}
110 	gd->ram_size = ram_size;
111 	if (ram_size == 0)
112 		return -1;
113 	return 0;
114 }
115 
116 int dram_init(void)
117 {
118 	int i, j;
119 
120 	if (CONFIG_NR_DRAM_BANKS) {
121 		for (i = 0, j = 0; i < lib_sysinfo.n_memranges; i++) {
122 			struct memrange *memrange = &lib_sysinfo.memrange[i];
123 
124 			if (memrange->type == CB_MEM_RAM) {
125 				gd->bd->bi_dram[j].start = memrange->base;
126 				gd->bd->bi_dram[j].size = memrange->size;
127 				j++;
128 				if (j >= CONFIG_NR_DRAM_BANKS)
129 					break;
130 			}
131 		}
132 	}
133 	return 0;
134 }
135