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-rw-r--r--qemu/roms/seabios/src/memmap.c144
1 files changed, 144 insertions, 0 deletions
diff --git a/qemu/roms/seabios/src/memmap.c b/qemu/roms/seabios/src/memmap.c
new file mode 100644
index 000000000..e03f8d0bf
--- /dev/null
+++ b/qemu/roms/seabios/src/memmap.c
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+// Support for building memory maps suitable for int 15 e820 calls.
+//
+// Copyright (C) 2008,2009 Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#include "config.h" // BUILD_MAX_E820
+#include "memmap.h" // struct e820entry
+#include "output.h" // dprintf
+#include "string.h" // memmove
+
+
+/****************************************************************
+ * e820 memory map
+ ****************************************************************/
+
+// Info on e820 map location and size.
+struct e820entry e820_list[BUILD_MAX_E820] VARFSEG;
+int e820_count VARFSEG;
+
+// Remove an entry from the e820_list.
+static void
+remove_e820(int i)
+{
+ e820_count--;
+ memmove(&e820_list[i], &e820_list[i+1]
+ , sizeof(e820_list[0]) * (e820_count - i));
+}
+
+// Insert an entry in the e820_list at the given position.
+static void
+insert_e820(int i, u64 start, u64 size, u32 type)
+{
+ if (e820_count >= BUILD_MAX_E820) {
+ warn_noalloc();
+ return;
+ }
+
+ memmove(&e820_list[i+1], &e820_list[i]
+ , sizeof(e820_list[0]) * (e820_count - i));
+ e820_count++;
+ struct e820entry *e = &e820_list[i];
+ e->start = start;
+ e->size = size;
+ e->type = type;
+}
+
+static const char *
+e820_type_name(u32 type)
+{
+ switch (type) {
+ case E820_RAM: return "RAM";
+ case E820_RESERVED: return "RESERVED";
+ case E820_ACPI: return "ACPI";
+ case E820_NVS: return "NVS";
+ case E820_UNUSABLE: return "UNUSABLE";
+ case E820_HOLE: return "HOLE";
+ default: return "UNKNOWN";
+ }
+}
+
+// Show the current e820_list.
+static void
+dump_map(void)
+{
+ dprintf(1, "e820 map has %d items:\n", e820_count);
+ int i;
+ for (i=0; i<e820_count; i++) {
+ struct e820entry *e = &e820_list[i];
+ u64 e_end = e->start + e->size;
+ dprintf(1, " %d: %016llx - %016llx = %d %s\n", i
+ , e->start, e_end, e->type, e820_type_name(e->type));
+ }
+}
+
+// Add a new entry to the list. This scans for overlaps and keeps the
+// list sorted.
+void
+add_e820(u64 start, u64 size, u32 type)
+{
+ dprintf(8, "Add to e820 map: %08x %08x %d\n", (u32)start, (u32)size, type);
+
+ if (! size)
+ // Huh? Nothing to do.
+ return;
+
+ // Find position of new item (splitting existing item if needed).
+ u64 end = start + size;
+ int i;
+ for (i=0; i<e820_count; i++) {
+ struct e820entry *e = &e820_list[i];
+ u64 e_end = e->start + e->size;
+ if (start > e_end)
+ continue;
+ // Found position - check if an existing item needs to be split.
+ if (start > e->start) {
+ if (type == e->type) {
+ // Same type - merge them.
+ size += start - e->start;
+ start = e->start;
+ } else {
+ // Split existing item.
+ e->size = start - e->start;
+ i++;
+ if (e_end > end)
+ insert_e820(i, end, e_end - end, e->type);
+ }
+ }
+ break;
+ }
+ // Remove/adjust existing items that are overlapping.
+ while (i<e820_count) {
+ struct e820entry *e = &e820_list[i];
+ if (end < e->start)
+ // No overlap - done.
+ break;
+ u64 e_end = e->start + e->size;
+ if (end >= e_end) {
+ // Existing item completely overlapped - remove it.
+ remove_e820(i);
+ continue;
+ }
+ // Not completely overlapped - adjust its start.
+ e->start = end;
+ e->size = e_end - end;
+ if (type == e->type) {
+ // Same type - merge them.
+ size += e->size;
+ remove_e820(i);
+ }
+ break;
+ }
+ // Insert new item.
+ if (type != E820_HOLE)
+ insert_e820(i, start, size, type);
+ //dump_map();
+}
+
+// Report on final memory locations.
+void
+memmap_prepboot(void)
+{
+ dump_map();
+}