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 #include "loongarch-stub.h"
  12
  13 typedef void __noreturn (*kernel_entry_t)(bool efi, unsigned long cmdline,
  14                                           unsigned long systab);
  15
  16 efi_status_t check_platform_features(void)
  17 {
  18         return EFI_SUCCESS;
  19 }
  20
  21 struct exit_boot_struct {
  22         efi_memory_desc_t       *runtime_map;
  23         int                     runtime_entry_count;
  24 };
  25
  26 static efi_status_t exit_boot_func(struct efi_boot_memmap *map, void *priv)
  27 {
  28         struct exit_boot_struct *p = priv;
  29
  30         /*
  31          * Update the memory map with virtual addresses. The function will also
  32          * populate @runtime_map with copies of just the EFI_MEMORY_RUNTIME
  33          * entries so that we can pass it straight to SetVirtualAddressMap()
  34          */
  35         efi_get_virtmap(map->map, map->map_size, map->desc_size,
  36                         p->runtime_map, &p->runtime_entry_count);
  37
  38         return EFI_SUCCESS;
  39 }
  40
  41 unsigned long __weak kernel_entry_address(unsigned long kernel_addr,
  42                 efi_loaded_image_t *image)
  43 {
  44         return *(unsigned long *)(kernel_addr + 8) - VMLINUX_LOAD_ADDRESS + kernel_addr;
  45 }
  46
  47 efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image,
  48                              unsigned long kernel_addr, char *cmdline_ptr)
  49 {
  50         kernel_entry_t real_kernel_entry;
  51         struct exit_boot_struct priv;
  52         unsigned long desc_size;
  53         efi_status_t status;
  54         u32 desc_ver;
  55
  56         status = efi_alloc_virtmap(&priv.runtime_map, &desc_size, &desc_ver);
  57         if (status != EFI_SUCCESS) {
  58                 efi_err("Unable to retrieve UEFI memory map.\n");
  59                 return status;
  60         }
  61
  62         efi_info("Exiting boot services\n");
  63
  64         efi_novamap = false;
  65         status = efi_exit_boot_services(handle, &priv, exit_boot_func);
  66         if (status != EFI_SUCCESS)
  67                 return status;
  68
  69         /* Install the new virtual address map */
  70         efi_rt_call(set_virtual_address_map,
  71                     priv.runtime_entry_count * desc_size, desc_size,
  72                     desc_ver, priv.runtime_map);
  73
  74         /* Config Direct Mapping */
  75         csr_write64(CSR_DMW0_INIT, LOONGARCH_CSR_DMWIN0);
  76         csr_write64(CSR_DMW1_INIT, LOONGARCH_CSR_DMWIN1);
  77
  78         real_kernel_entry = (void *)kernel_entry_address(kernel_addr, image);
  79
  80         real_kernel_entry(true, (unsigned long)cmdline_ptr,
  81                           (unsigned long)efi_system_table);
  82 }