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Kevin O'Connor59a23bb2008-06-08 23:09:42 -04001// Support for building memory maps suitable for int 15 e820 calls.
2//
3// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
4//
Kevin O'Connorb1b7c2a2009-01-15 20:52:58 -05005// This file may be distributed under the terms of the GNU LGPLv3 license.
Kevin O'Connor59a23bb2008-06-08 23:09:42 -04006
7#include "memmap.h" // struct e820entry
8#include "util.h" // dprintf.h
Kevin O'Connor9521e262008-07-04 13:04:29 -04009#include "biosvar.h" // SET_EBDA
Kevin O'Connor59a23bb2008-06-08 23:09:42 -040010
Kevin O'Connor59a23bb2008-06-08 23:09:42 -040011// Remove an entry from the e820_list.
12static void
13remove_e820(int i)
14{
15 e820_count--;
16 memmove(&e820_list[i], &e820_list[i+1]
17 , sizeof(e820_list[0]) * (e820_count - i));
18}
19
20// Insert an entry in the e820_list at the given position.
21static void
22insert_e820(int i, u64 start, u64 size, u32 type)
23{
Kevin O'Connord995b3d2008-11-08 13:05:27 -050024 if (e820_count >= CONFIG_MAX_E820) {
Kevin O'Connor59a23bb2008-06-08 23:09:42 -040025 dprintf(1, "Overflowed e820 list!\n");
26 return;
27 }
28
29 memmove(&e820_list[i+1], &e820_list[i]
30 , sizeof(e820_list[0]) * (e820_count - i));
31 e820_count++;
32 struct e820entry *e = &e820_list[i];
33 e->start = start;
34 e->size = size;
35 e->type = type;
36}
37
38// Show the current e820_list.
39static void
40dump_map()
41{
42 dprintf(1, "e820 map has %d items:\n", e820_count);
43 int i;
44 for (i=0; i<e820_count; i++) {
45 struct e820entry *e = &e820_list[i];
46 u64 e_end = e->start + e->size;
47 dprintf(1, " %d: %x%x - %x%x = %d\n", i
48 , (u32)(e->start >> 32), (u32)e->start
49 , (u32)(e_end >> 32), (u32)e_end
50 , e->type);
51 }
52}
53
54// Add a new entry to the list. This scans for overlaps and keeps the
55// list sorted.
56void
57add_e820(u64 start, u64 size, u32 type)
58{
59 dprintf(8, "Add to e820 map: %x %x %d\n", (u32)start, (u32)size, type);
60
61 if (! size)
62 // Huh? Nothing to do.
63 return;
64
Kevin O'Connor5d8ec3e2009-02-27 20:19:27 -050065 // Find position of new item (splitting existing item if needed).
Kevin O'Connor59a23bb2008-06-08 23:09:42 -040066 u64 end = start + size;
67 int i;
68 for (i=0; i<e820_count; i++) {
69 struct e820entry *e = &e820_list[i];
Kevin O'Connor59a23bb2008-06-08 23:09:42 -040070 u64 e_end = e->start + e->size;
Kevin O'Connoraa0c66d2008-06-11 21:23:24 -040071 if (start > e_end)
Kevin O'Connor59a23bb2008-06-08 23:09:42 -040072 continue;
Kevin O'Connor5d8ec3e2009-02-27 20:19:27 -050073 // Found position - check if an existing item needs to be split.
Kevin O'Connor59a23bb2008-06-08 23:09:42 -040074 if (start > e->start) {
Kevin O'Connoraa0c66d2008-06-11 21:23:24 -040075 if (type == e->type) {
76 // Same type - merge them.
77 size += start - e->start;
78 start = e->start;
Kevin O'Connor1bedcc02009-04-26 21:25:53 -040079 } else {
80 // Split existing item.
81 e->size = start - e->start;
82 i++;
83 if (e_end > end)
84 insert_e820(i, end, e_end - end, e->type);
Kevin O'Connoraa0c66d2008-06-11 21:23:24 -040085 }
Kevin O'Connor59a23bb2008-06-08 23:09:42 -040086 }
Kevin O'Connor5d8ec3e2009-02-27 20:19:27 -050087 break;
Kevin O'Connor59a23bb2008-06-08 23:09:42 -040088 }
Kevin O'Connor5d8ec3e2009-02-27 20:19:27 -050089 // Remove/adjust existing items that are overlapping.
90 while (i<e820_count) {
91 struct e820entry *e = &e820_list[i];
92 if (end < e->start)
93 // No overlap - done.
94 break;
95 u64 e_end = e->start + e->size;
96 if (end >= e_end) {
97 // Existing item completely overlapped - remove it.
98 remove_e820(i);
99 continue;
100 }
101 // Not completely overlapped - adjust its start.
102 e->start = end;
Kevin O'Connor1bedcc02009-04-26 21:25:53 -0400103 e->size = e_end - end;
Kevin O'Connor5d8ec3e2009-02-27 20:19:27 -0500104 if (type == e->type) {
105 // Same type - merge them.
Kevin O'Connor1bedcc02009-04-26 21:25:53 -0400106 size += e->size;
Kevin O'Connor5d8ec3e2009-02-27 20:19:27 -0500107 remove_e820(i);
108 }
109 break;
110 }
Kevin O'Connor1bedcc02009-04-26 21:25:53 -0400111 // Insert new item.
112 if (type != E820_HOLE)
113 insert_e820(i, start, size, type);
Kevin O'Connor59a23bb2008-06-08 23:09:42 -0400114 //dump_map();
115}
116
Kevin O'Connor59a23bb2008-06-08 23:09:42 -0400117// Prep for memmap stuff - init bios table locations.
118void
119memmap_setup()
120{
Kevin O'Connor07633812009-02-17 22:36:49 -0500121 memset(BiosTableSpace, 0, CONFIG_MAX_BIOSTABLE);
Kevin O'Connordf2c19a2009-01-17 20:07:09 -0500122 bios_table_cur_addr = (u32)BiosTableSpace;
123 bios_table_end_addr = bios_table_cur_addr + CONFIG_MAX_BIOSTABLE;
Kevin O'Connor59a23bb2008-06-08 23:09:42 -0400124 dprintf(1, "bios_table_addr: 0x%08x end=0x%08x\n",
125 bios_table_cur_addr, bios_table_end_addr);
Kevin O'Connord995b3d2008-11-08 13:05:27 -0500126
Kevin O'Connoracf13742008-11-29 11:19:19 -0500127 e820_count = 0;
Kevin O'Connor59a23bb2008-06-08 23:09:42 -0400128}
129
Kevin O'Connor9649a962008-12-10 20:53:35 -0500130// Report on final memory locations.
Kevin O'Connor59a23bb2008-06-08 23:09:42 -0400131void
132memmap_finalize()
133{
134 dump_map();
135
Kevin O'Connor15b31652008-08-29 21:21:09 -0400136 dprintf(1, "final bios_table_addr: 0x%08x (used %d%%)\n"
137 , bios_table_cur_addr
Kevin O'Connordf2c19a2009-01-17 20:07:09 -0500138 , (100 * (bios_table_cur_addr - (u32)&BiosTableSpace)
139 / CONFIG_MAX_BIOSTABLE));
Kevin O'Connor0525d292008-07-04 06:18:30 -0400140 if (bios_table_cur_addr > bios_table_end_addr)
Kevin O'Connore07e18e2009-02-08 17:07:29 -0500141 panic("bios_table_end_addr overflow!\n");
Kevin O'Connor59a23bb2008-06-08 23:09:42 -0400142}