historical/m0-applesillicon.git/xnu-qemu-arm64-5.1.0/hw/i386/e820_memory_layout.c
2024-01-16 11:20:27 -06:00

59 lines
1.5 KiB
C

/*
* QEMU BIOS e820 routines
*
* Copyright (c) 2003-2004 Fabrice Bellard
*
* SPDX-License-Identifier: MIT
*/
#include "qemu/osdep.h"
#include "qemu/bswap.h"
#include "e820_memory_layout.h"
static size_t e820_entries;
struct e820_table e820_reserve;
struct e820_entry *e820_table;
int e820_add_entry(uint64_t address, uint64_t length, uint32_t type)
{
int index = le32_to_cpu(e820_reserve.count);
struct e820_entry *entry;
if (type != E820_RAM) {
/* old FW_CFG_E820_TABLE entry -- reservations only */
if (index >= E820_NR_ENTRIES) {
return -EBUSY;
}
entry = &e820_reserve.entry[index++];
entry->address = cpu_to_le64(address);
entry->length = cpu_to_le64(length);
entry->type = cpu_to_le32(type);
e820_reserve.count = cpu_to_le32(index);
}
/* new "etc/e820" file -- include ram too */
e820_table = g_renew(struct e820_entry, e820_table, e820_entries + 1);
e820_table[e820_entries].address = cpu_to_le64(address);
e820_table[e820_entries].length = cpu_to_le64(length);
e820_table[e820_entries].type = cpu_to_le32(type);
e820_entries++;
return e820_entries;
}
int e820_get_num_entries(void)
{
return e820_entries;
}
bool e820_get_entry(int idx, uint32_t type, uint64_t *address, uint64_t *length)
{
if (idx < e820_entries && e820_table[idx].type == cpu_to_le32(type)) {
*address = le64_to_cpu(e820_table[idx].address);
*length = le64_to_cpu(e820_table[idx].length);
return true;
}
return false;
}