drivers/firmware/efi/libstub/loongarch.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Author: Yun Liu <liuyun@loongson.cn>
   4  *         Huacai Chen <chenhuacai@loongson.cn>
   5  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
   6  */
   7
   8 #include <asm/efi.h>
   9 #include <asm/addrspace.h>
  10 #include "efistub.h"
  11
  12 typedef void __noreturn (*kernel_entry_t)(bool efi, unsigned long cmdline,
  13                                           unsigned long systab);
  14
  15 efi_status_t check_platform_features(void)
  16 {
  17         return EFI_SUCCESS;
  18 }
  19
  20 struct exit_boot_struct {
  21         efi_memory_desc_t       *runtime_map;
  22         int                     runtime_entry_count;
  23 };
  24
  25 static efi_status_t exit_boot_func(struct efi_boot_memmap *map, void *priv)
  26 {
  27         struct exit_boot_struct *p = priv;
  28
  29         /*
  30          * Update the memory map with virtual addresses. The function will also
  31          * populate @runtime_map with copies of just the EFI_MEMORY_RUNTIME
  32          * entries so that we can pass it straight to SetVirtualAddressMap()
  33          */
  34         efi_get_virtmap(map->map, map->map_size, map->desc_size,
  35                         p->runtime_map, &p->runtime_entry_count);
  36
  37         return EFI_SUCCESS;
  38 }
  39
  40 unsigned long __weak kernel_entry_address(void)
  41 {
  42         return *(unsigned long *)(PHYSADDR(VMLINUX_LOAD_ADDRESS) + 8);
  43 }
  44
  45 efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image,
  46                              unsigned long kernel_addr, char *cmdline_ptr)
  47 {
  48         kernel_entry_t real_kernel_entry;
  49         struct exit_boot_struct priv;
  50         unsigned long desc_size;
  51         efi_status_t status;
  52         u32 desc_ver;
  53
  54         status = efi_alloc_virtmap(&priv.runtime_map, &desc_size, &desc_ver);
  55         if (status != EFI_SUCCESS) {
  56                 efi_err("Unable to retrieve UEFI memory map.\n");
  57                 return status;
  58         }
  59
  60         efi_info("Exiting boot services\n");
  61
  62         efi_novamap = false;
  63         status = efi_exit_boot_services(handle, &priv, exit_boot_func);
  64         if (status != EFI_SUCCESS)
  65                 return status;
  66
  67         /* Install the new virtual address map */
  68         efi_rt_call(set_virtual_address_map,
  69                     priv.runtime_entry_count * desc_size, desc_size,
  70                     desc_ver, priv.runtime_map);
  71
  72         /* Config Direct Mapping */
  73         csr_write64(CSR_DMW0_INIT, LOONGARCH_CSR_DMWIN0);
  74         csr_write64(CSR_DMW1_INIT, LOONGARCH_CSR_DMWIN1);
  75
  76         real_kernel_entry = (void *)kernel_entry_address();
  77
  78         real_kernel_entry(true, (unsigned long)cmdline_ptr,
  79                           (unsigned long)efi_system_table);
  80 }