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/screen_info.h>
  22 #include <linux/uaccess.h>
  23
  24 #include <asm/early_ioremap.h>
  25 #include <asm/efi.h>
  26 #include <asm/loongson.h>
  27
  28 static unsigned long efi_nr_tables;
  29 static unsigned long efi_config_table;
  30
  31 static unsigned long __initdata boot_memmap = EFI_INVALID_TABLE_ADDR;
  32 static unsigned long __initdata fdt_pointer = EFI_INVALID_TABLE_ADDR;
  33
  34 static efi_system_table_t *efi_systab;
  35 static efi_config_table_type_t arch_tables[] __initdata = {
  36         {LINUX_EFI_BOOT_MEMMAP_GUID,    &boot_memmap,   "MEMMAP" },
  37         {DEVICE_TREE_GUID,              &fdt_pointer,   "FDTPTR" },
  38         {},
  39 };
  40
  41 void __init *efi_fdt_pointer(void)
  42 {
  43         if (!efi_systab)
  44                 return NULL;
  45
  46         if (fdt_pointer == EFI_INVALID_TABLE_ADDR)
  47                 return NULL;
  48
  49         return early_memremap_ro(fdt_pointer, SZ_64K);
  50 }
  51
  52 void __init efi_runtime_init(void)
  53 {
  54         if (!efi_enabled(EFI_BOOT) || !efi_systab->runtime)
  55                 return;
  56
  57         if (efi_runtime_disabled()) {
  58                 pr_info("EFI runtime services will be disabled.\n");
  59                 return;
  60         }
  61
  62         efi.runtime = (efi_runtime_services_t *)efi_systab->runtime;
  63         efi.runtime_version = (unsigned int)efi.runtime->hdr.revision;
  64
  65         efi_native_runtime_setup();
  66         set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
  67 }
  68
  69 unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR;
  70
  71 #if defined(CONFIG_SYSFB) || defined(CONFIG_EFI_EARLYCON)
  72 struct screen_info screen_info __section(".data");
  73 EXPORT_SYMBOL_GPL(screen_info);
  74 #endif
  75
  76 static void __init init_screen_info(void)
  77 {
  78         struct screen_info *si;
  79
  80         if (screen_info_table == EFI_INVALID_TABLE_ADDR)
  81                 return;
  82
  83         si = early_memremap(screen_info_table, sizeof(*si));
  84         if (!si) {
  85                 pr_err("Could not map screen_info config table\n");
  86                 return;
  87         }
  88         screen_info = *si;
  89         memset(si, 0, sizeof(*si));
  90         early_memunmap(si, sizeof(*si));
  91
  92         memblock_reserve(screen_info.lfb_base, screen_info.lfb_size);
  93 }
  94
  95 void __init efi_init(void)
  96 {
  97         int size;
  98         void *config_tables;
  99         struct efi_boot_memmap *tbl;
 100
 101         if (!efi_system_table)
 102                 return;
 103
 104         efi_systab = (efi_system_table_t *)early_memremap_ro(efi_system_table, sizeof(*efi_systab));
 105         if (!efi_systab) {
 106                 pr_err("Can't find EFI system table.\n");
 107                 return;
 108         }
 109
 110         efi_systab_report_header(&efi_systab->hdr, efi_systab->fw_vendor);
 111
 112         set_bit(EFI_64BIT, &efi.flags);
 113         efi_nr_tables    = efi_systab->nr_tables;
 114         efi_config_table = (unsigned long)efi_systab->tables;
 115
 116         size = sizeof(efi_config_table_t);
 117         config_tables = early_memremap(efi_config_table, efi_nr_tables * size);
 118         efi_config_parse_tables(config_tables, efi_systab->nr_tables, arch_tables);
 119         early_memunmap(config_tables, efi_nr_tables * size);
 120
 121         set_bit(EFI_CONFIG_TABLES, &efi.flags);
 122
 123         if (IS_ENABLED(CONFIG_EFI_EARLYCON) || IS_ENABLED(CONFIG_SYSFB))
 124                 init_screen_info();
 125
 126         if (boot_memmap == EFI_INVALID_TABLE_ADDR)
 127                 return;
 128
 129         tbl = early_memremap_ro(boot_memmap, sizeof(*tbl));
 130         if (tbl) {
 131                 struct efi_memory_map_data data;
 132
 133                 data.phys_map           = boot_memmap + sizeof(*tbl);
 134                 data.size               = tbl->map_size;
 135                 data.desc_size          = tbl->desc_size;
 136                 data.desc_version       = tbl->desc_ver;
 137
 138                 if (efi_memmap_init_early(&data) < 0)
 139                         panic("Unable to map EFI memory map.\n");
 140
 141                 early_memunmap(tbl, sizeof(*tbl));
 142         }
 143 }