arch/loongarch/kernel/efi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * EFI initialization
   4  *
   5  * Author: Jianmin Lv <lvjianmin@loongson.cn>
   6  *         Huacai Chen <chenhuacai@loongson.cn>
   7  *
   8  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
   9  */
  10
  11 #include <linux/acpi.h>
  12 #include <linux/efi.h>
  13 #include <linux/efi-bgrt.h>
  14 #include <linux/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/export.h>
  17 #include <linux/io.h>
  18 #include <linux/kobject.h>
  19 #include <linux/memblock.h>
  20 #include <linux/reboot.h>
  21 #include <linux/uaccess.h>
  22
  23 #include <asm/early_ioremap.h>
  24 #include <asm/efi.h>
  25 #include <asm/loongson.h>
  26
  27 static unsigned long efi_nr_tables;
  28 static unsigned long efi_config_table;
  29
  30 static unsigned long __initdata boot_memmap = EFI_INVALID_TABLE_ADDR;
  31
  32 static efi_system_table_t *efi_systab;
  33 static efi_config_table_type_t arch_tables[] __initdata = {
  34         {LINUX_EFI_BOOT_MEMMAP_GUID,    &boot_memmap,   "MEMMAP" },
  35         {},
  36 };
  37
  38 void __init efi_runtime_init(void)
  39 {
  40         if (!efi_enabled(EFI_BOOT))
  41                 return;
  42
  43         if (efi_runtime_disabled()) {
  44                 pr_info("EFI runtime services will be disabled.\n");
  45                 return;
  46         }
  47
  48         efi.runtime = (efi_runtime_services_t *)efi_systab->runtime;
  49         efi.runtime_version = (unsigned int)efi.runtime->hdr.revision;
  50
  51         efi_native_runtime_setup();
  52         set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
  53 }
  54
  55 unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR;
  56
  57 static void __init init_screen_info(void)
  58 {
  59         struct screen_info *si;
  60
  61         if (screen_info_table == EFI_INVALID_TABLE_ADDR)
  62                 return;
  63
  64         si = early_memremap(screen_info_table, sizeof(*si));
  65         if (!si) {
  66                 pr_err("Could not map screen_info config table\n");
  67                 return;
  68         }
  69         screen_info = *si;
  70         memset(si, 0, sizeof(*si));
  71         early_memunmap(si, sizeof(*si));
  72
  73         memblock_reserve(screen_info.lfb_base, screen_info.lfb_size);
  74 }
  75
  76 void __init efi_init(void)
  77 {
  78         int size;
  79         void *config_tables;
  80         struct efi_boot_memmap *tbl;
  81
  82         if (!efi_system_table)
  83                 return;
  84
  85         efi_systab = (efi_system_table_t *)early_memremap_ro(efi_system_table, sizeof(*efi_systab));
  86         if (!efi_systab) {
  87                 pr_err("Can't find EFI system table.\n");
  88                 return;
  89         }
  90
  91         efi_systab_report_header(&efi_systab->hdr, efi_systab->fw_vendor);
  92
  93         set_bit(EFI_64BIT, &efi.flags);
  94         efi_nr_tables    = efi_systab->nr_tables;
  95         efi_config_table = (unsigned long)efi_systab->tables;
  96
  97         size = sizeof(efi_config_table_t);
  98         config_tables = early_memremap(efi_config_table, efi_nr_tables * size);
  99         efi_config_parse_tables(config_tables, efi_systab->nr_tables, arch_tables);
 100         early_memunmap(config_tables, efi_nr_tables * size);
 101
 102         set_bit(EFI_CONFIG_TABLES, &efi.flags);
 103
 104         init_screen_info();
 105
 106         if (boot_memmap == EFI_INVALID_TABLE_ADDR)
 107                 return;
 108
 109         tbl = early_memremap_ro(boot_memmap, sizeof(*tbl));
 110         if (tbl) {
 111                 struct efi_memory_map_data data;
 112
 113                 data.phys_map           = boot_memmap + sizeof(*tbl);
 114                 data.size               = tbl->map_size;
 115                 data.desc_size          = tbl->desc_size;
 116                 data.desc_version       = tbl->desc_ver;
 117
 118                 if (efi_memmap_init_early(&data) < 0)
 119                         panic("Unable to map EFI memory map.\n");
 120
 121                 early_memunmap(tbl, sizeof(*tbl));
 122         }
 123 }