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
check_platform_features(void)16 efi_status_t check_platform_features(void)
17 {
18 return EFI_SUCCESS;
19 }
20
efi_cache_sync_image(unsigned long image_base,unsigned long alloc_size)21 void efi_cache_sync_image(unsigned long image_base, unsigned long alloc_size)
22 {
23 asm volatile ("ibar 0" ::: "memory");
24 }
25
efi_get_kimg_kaslr_address(void)26 unsigned long efi_get_kimg_kaslr_address(void)
27 {
28 unsigned int random_offset = 0;
29
30 #ifdef CONFIG_RANDOMIZE_BASE
31 if (!efi_nokaslr) {
32 efi_get_random_bytes(sizeof(random_offset), (u8 *)&random_offset);
33 random_offset ^= (random_get_entropy() << 16);
34 random_offset &= (CONFIG_RANDOMIZE_BASE_MAX_OFFSET - 1);
35 random_offset = ALIGN(random_offset + SZ_64K, SZ_64K);
36 }
37 #endif
38
39 return PHYSADDR(VMLINUX_LOAD_ADDRESS) + random_offset;
40 }
41
42 struct exit_boot_struct {
43 efi_memory_desc_t *runtime_map;
44 int runtime_entry_count;
45 };
46
exit_boot_func(struct efi_boot_memmap * map,void * priv)47 static efi_status_t exit_boot_func(struct efi_boot_memmap *map, void *priv)
48 {
49 struct exit_boot_struct *p = priv;
50
51 /*
52 * Update the memory map with virtual addresses. The function will also
53 * populate @runtime_map with copies of just the EFI_MEMORY_RUNTIME
54 * entries so that we can pass it straight to SetVirtualAddressMap()
55 */
56 efi_get_virtmap(map->map, map->map_size, map->desc_size,
57 p->runtime_map, &p->runtime_entry_count);
58
59 return EFI_SUCCESS;
60 }
61
kernel_entry_address(unsigned long kernel_addr,efi_loaded_image_t * image)62 unsigned long __weak kernel_entry_address(unsigned long kernel_addr,
63 efi_loaded_image_t *image)
64 {
65 return *(unsigned long *)(kernel_addr + 8) - PHYSADDR(VMLINUX_LOAD_ADDRESS) + kernel_addr;
66 }
67
efi_boot_kernel(void * handle,efi_loaded_image_t * image,unsigned long kernel_addr,char * cmdline_ptr)68 efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image,
69 unsigned long kernel_addr, char *cmdline_ptr)
70 {
71 kernel_entry_t real_kernel_entry;
72 struct exit_boot_struct priv;
73 unsigned long desc_size;
74 efi_status_t status;
75 u32 desc_ver;
76
77 status = efi_alloc_virtmap(&priv.runtime_map, &desc_size, &desc_ver);
78 if (status != EFI_SUCCESS) {
79 efi_err("Unable to retrieve UEFI memory map.\n");
80 return status;
81 }
82
83 efi_info("Exiting boot services\n");
84
85 efi_novamap = false;
86 status = efi_exit_boot_services(handle, &priv, exit_boot_func);
87 if (status != EFI_SUCCESS)
88 return status;
89
90 /* Install the new virtual address map */
91 efi_rt_call(set_virtual_address_map,
92 priv.runtime_entry_count * desc_size, desc_size,
93 desc_ver, priv.runtime_map);
94
95 /* Config Direct Mapping */
96 csr_write(CSR_DMW0_INIT, LOONGARCH_CSR_DMWIN0);
97 csr_write(CSR_DMW1_INIT, LOONGARCH_CSR_DMWIN1);
98 csr_write(CSR_DMW2_INIT, LOONGARCH_CSR_DMWIN2);
99 csr_write(CSR_DMW3_INIT, LOONGARCH_CSR_DMWIN3);
100
101 real_kernel_entry = (void *)kernel_entry_address(kernel_addr, image);
102
103 real_kernel_entry(true, (unsigned long)cmdline_ptr,
104 (unsigned long)efi_system_table);
105 }
106