arch/loongarch/kernel/efi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * EFI initialization
   4  *
   5  * Author: Jianmin Lv <[email protected]>
   6  *         Huacai Chen <[email protected]>
   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 bool efi_poweroff_required(void)
  70 {
  71         return efi_enabled(EFI_RUNTIME_SERVICES) &&
  72                 (acpi_gbl_reduced_hardware || acpi_no_s5);
  73 }
  74
  75 unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR;
  76
  77 #if defined(CONFIG_SYSFB) || defined(CONFIG_EFI_EARLYCON)
  78 struct screen_info screen_info __section(".data");
  79 EXPORT_SYMBOL_GPL(screen_info);
  80 #endif
  81
  82 static void __init init_screen_info(void)
  83 {
  84         struct screen_info *si;
  85
  86         if (screen_info_table == EFI_INVALID_TABLE_ADDR)
  87                 return;
  88
  89         si = early_memremap(screen_info_table, sizeof(*si));
  90         if (!si) {
  91                 pr_err("Could not map screen_info config table\n");
  92                 return;
  93         }
  94         screen_info = *si;
  95         memset(si, 0, sizeof(*si));
  96         early_memunmap(si, sizeof(*si));
  97
  98         memblock_reserve(__screen_info_lfb_base(&screen_info), screen_info.lfb_size);
  99 }
 100
 101 void __init efi_init(void)
 102 {
 103         int size;
 104         void *config_tables;
 105         struct efi_boot_memmap *tbl;
 106
 107         if (!efi_system_table)
 108                 return;
 109
 110         efi_systab = (efi_system_table_t *)early_memremap_ro(efi_system_table, sizeof(*efi_systab));
 111         if (!efi_systab) {
 112                 pr_err("Can't find EFI system table.\n");
 113                 return;
 114         }
 115
 116         efi_systab_report_header(&efi_systab->hdr, efi_systab->fw_vendor);
 117
 118         set_bit(EFI_64BIT, &efi.flags);
 119         efi_nr_tables    = efi_systab->nr_tables;
 120         efi_config_table = (unsigned long)efi_systab->tables;
 121
 122         size = sizeof(efi_config_table_t);
 123         config_tables = early_memremap(efi_config_table, efi_nr_tables * size);
 124         efi_config_parse_tables(config_tables, efi_systab->nr_tables, arch_tables);
 125         early_memunmap(config_tables, efi_nr_tables * size);
 126
 127         set_bit(EFI_CONFIG_TABLES, &efi.flags);
 128
 129         if (IS_ENABLED(CONFIG_EFI_EARLYCON) || IS_ENABLED(CONFIG_SYSFB))
 130                 init_screen_info();
 131
 132         if (boot_memmap == EFI_INVALID_TABLE_ADDR)
 133                 return;
 134
 135         tbl = early_memremap_ro(boot_memmap, sizeof(*tbl));
 136         if (tbl) {
 137                 struct efi_memory_map_data data;
 138
 139                 data.phys_map           = boot_memmap + sizeof(*tbl);
 140                 data.size               = tbl->map_size;
 141                 data.desc_size          = tbl->desc_size;
 142                 data.desc_version       = tbl->desc_ver;
 143
 144                 if (efi_memmap_init_early(&data) < 0)
 145                         panic("Unable to map EFI memory map.\n");
 146
 147                 early_memunmap(tbl, sizeof(*tbl));
 148         }
 149
 150         efi_esrt_init();
 151 }