arch/x86/cpu/qemu/e820.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * QEMU x86 specific E820 table generation
   4  *
   5  * (C) Copyright 2015 Miao Yan <[email protected]>
   6  * (C) Copyright 2019 Bin Meng <[email protected]>
   7  */
   8
   9 #include <env_internal.h>
  10 #include <malloc.h>
  11 #include <asm/e820.h>
  12 #include <asm/arch/qemu.h>
  13 #include <asm/global_data.h>
  14 #include <linux/sizes.h>
  15
  16 DECLARE_GLOBAL_DATA_PTR;
  17
  18 unsigned int install_e820_map(unsigned int max_entries,
  19                               struct e820_entry *entries)
  20 {
  21         u64 high_mem_size;
  22         int n = 0;
  23
  24         entries[n].addr = 0;
  25         entries[n].size = ISA_START_ADDRESS;
  26         entries[n].type = E820_RAM;
  27         n++;
  28
  29         entries[n].addr = ISA_START_ADDRESS;
  30         entries[n].size = ISA_END_ADDRESS - ISA_START_ADDRESS;
  31         entries[n].type = E820_RESERVED;
  32         n++;
  33
  34         /*
  35          * since we use memalign(malloc) to allocate high memory for
  36          * storing ACPI tables, we need to reserve them in e820 tables,
  37          * otherwise kernel will reclaim them and data will be corrupted
  38          */
  39         entries[n].addr = ISA_END_ADDRESS;
  40         entries[n].size = gd->relocaddr - TOTAL_MALLOC_LEN - ISA_END_ADDRESS;
  41         entries[n].type = E820_RAM;
  42         n++;
  43
  44         /* for simplicity, reserve entire malloc space */
  45         entries[n].addr = gd->relocaddr - TOTAL_MALLOC_LEN;
  46         entries[n].size = TOTAL_MALLOC_LEN;
  47         entries[n].type = E820_RESERVED;
  48         n++;
  49
  50         entries[n].addr = gd->relocaddr;
  51         entries[n].size = qemu_get_low_memory_size() - gd->relocaddr;
  52         entries[n].type = E820_RESERVED;
  53         n++;
  54
  55         entries[n].addr = CONFIG_PCIE_ECAM_BASE;
  56         entries[n].size = CONFIG_PCIE_ECAM_SIZE;
  57         entries[n].type = E820_RESERVED;
  58         n++;
  59
  60         high_mem_size = qemu_get_high_memory_size();
  61         if (high_mem_size) {
  62                 entries[n].addr = SZ_4G;
  63                 entries[n].size = high_mem_size;
  64                 entries[n].type = E820_RAM;
  65                 n++;
  66         }
  67
  68         return n;
  69 }