12e0eb483SAtish Patra // SPDX-License-Identifier: GPL-2.0-only
22e0eb483SAtish Patra /*
32e0eb483SAtish Patra * EFI stub implementation that is shared by arm and arm64 architectures.
42e0eb483SAtish Patra * This should be #included by the EFI stub implementation files.
52e0eb483SAtish Patra *
62e0eb483SAtish Patra * Copyright (C) 2013,2014 Linaro Limited
72e0eb483SAtish Patra * Roy Franz <roy.franz@linaro.org
82e0eb483SAtish Patra * Copyright (C) 2013 Red Hat, Inc.
92e0eb483SAtish Patra * Mark Salter <msalter@redhat.com>
102e0eb483SAtish Patra */
112e0eb483SAtish Patra
122e0eb483SAtish Patra #include <linux/efi.h>
132e0eb483SAtish Patra #include <asm/efi.h>
142e0eb483SAtish Patra
152e0eb483SAtish Patra #include "efistub.h"
162e0eb483SAtish Patra
172e0eb483SAtish Patra /*
182e0eb483SAtish Patra * This is the base address at which to start allocating virtual memory ranges
19b91540d5SAtish Patra * for UEFI Runtime Services.
20b91540d5SAtish Patra *
21b91540d5SAtish Patra * For ARM/ARM64:
22b91540d5SAtish Patra * This is in the low TTBR0 range so that we can use
232e0eb483SAtish Patra * any allocation we choose, and eliminate the risk of a conflict after kexec.
242e0eb483SAtish Patra * The value chosen is the largest non-zero power of 2 suitable for this purpose
252e0eb483SAtish Patra * both on 32-bit and 64-bit ARM CPUs, to maximize the likelihood that it can
262e0eb483SAtish Patra * be mapped efficiently.
272e0eb483SAtish Patra * Since 32-bit ARM could potentially execute with a 1G/3G user/kernel split,
282e0eb483SAtish Patra * map everything below 1 GB. (512 MB is a reasonable upper bound for the
292e0eb483SAtish Patra * entire footprint of the UEFI runtime services memory regions)
30b91540d5SAtish Patra *
31b91540d5SAtish Patra * For RISC-V:
32b91540d5SAtish Patra * There is no specific reason for which, this address (512MB) can't be used
33b91540d5SAtish Patra * EFI runtime virtual address for RISC-V. It also helps to use EFI runtime
34b91540d5SAtish Patra * services on both RV32/RV64. Keep the same runtime virtual address for RISC-V
35b91540d5SAtish Patra * as well to minimize the code churn.
362e0eb483SAtish Patra */
372e0eb483SAtish Patra #define EFI_RT_VIRTUAL_BASE SZ_512M
382e0eb483SAtish Patra
39ead384d9SHuacai Chen /*
40ead384d9SHuacai Chen * Some architectures map the EFI regions into the kernel's linear map using a
41ead384d9SHuacai Chen * fixed offset.
42ead384d9SHuacai Chen */
43ead384d9SHuacai Chen #ifndef EFI_RT_VIRTUAL_OFFSET
44ead384d9SHuacai Chen #define EFI_RT_VIRTUAL_OFFSET 0
45ead384d9SHuacai Chen #endif
46ead384d9SHuacai Chen
472e0eb483SAtish Patra static u64 virtmap_base = EFI_RT_VIRTUAL_BASE;
48ead384d9SHuacai Chen static bool flat_va_mapping = (EFI_RT_VIRTUAL_OFFSET != 0);
492e0eb483SAtish Patra
free_screen_info(struct screen_info * si)50732ea9dbSArd Biesheuvel void __weak free_screen_info(struct screen_info *si)
51732ea9dbSArd Biesheuvel {
52732ea9dbSArd Biesheuvel }
53732ea9dbSArd Biesheuvel
setup_graphics(void)542e0eb483SAtish Patra static struct screen_info *setup_graphics(void)
552e0eb483SAtish Patra {
562e0eb483SAtish Patra efi_guid_t gop_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
572e0eb483SAtish Patra efi_status_t status;
582e0eb483SAtish Patra unsigned long size;
592e0eb483SAtish Patra void **gop_handle = NULL;
602e0eb483SAtish Patra struct screen_info *si = NULL;
612e0eb483SAtish Patra
622e0eb483SAtish Patra size = 0;
632e0eb483SAtish Patra status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
642e0eb483SAtish Patra &gop_proto, NULL, &size, gop_handle);
652e0eb483SAtish Patra if (status == EFI_BUFFER_TOO_SMALL) {
662e0eb483SAtish Patra si = alloc_screen_info();
672e0eb483SAtish Patra if (!si)
682e0eb483SAtish Patra return NULL;
69a5d8e55bSIngo Molnar status = efi_setup_gop(si, &gop_proto, size);
70a5d8e55bSIngo Molnar if (status != EFI_SUCCESS) {
71a5d8e55bSIngo Molnar free_screen_info(si);
72a5d8e55bSIngo Molnar return NULL;
73a5d8e55bSIngo Molnar }
742e0eb483SAtish Patra }
752e0eb483SAtish Patra return si;
762e0eb483SAtish Patra }
772e0eb483SAtish Patra
install_memreserve_table(void)7887cd6378SZou Wei static void install_memreserve_table(void)
792e0eb483SAtish Patra {
802e0eb483SAtish Patra struct linux_efi_memreserve *rsv;
812e0eb483SAtish Patra efi_guid_t memreserve_table_guid = LINUX_EFI_MEMRESERVE_TABLE_GUID;
822e0eb483SAtish Patra efi_status_t status;
832e0eb483SAtish Patra
842e0eb483SAtish Patra status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, sizeof(*rsv),
852e0eb483SAtish Patra (void **)&rsv);
862e0eb483SAtish Patra if (status != EFI_SUCCESS) {
87793473c2SArvind Sankar efi_err("Failed to allocate memreserve entry!\n");
882e0eb483SAtish Patra return;
892e0eb483SAtish Patra }
902e0eb483SAtish Patra
912e0eb483SAtish Patra rsv->next = 0;
922e0eb483SAtish Patra rsv->size = 0;
932e0eb483SAtish Patra atomic_set(&rsv->count, 0);
942e0eb483SAtish Patra
952e0eb483SAtish Patra status = efi_bs_call(install_configuration_table,
962e0eb483SAtish Patra &memreserve_table_guid, rsv);
972e0eb483SAtish Patra if (status != EFI_SUCCESS)
98793473c2SArvind Sankar efi_err("Failed to install memreserve config table!\n");
992e0eb483SAtish Patra }
1002e0eb483SAtish Patra
get_supported_rt_services(void)1019e9888a0SArd Biesheuvel static u32 get_supported_rt_services(void)
1029e9888a0SArd Biesheuvel {
1039e9888a0SArd Biesheuvel const efi_rt_properties_table_t *rt_prop_table;
1049e9888a0SArd Biesheuvel u32 supported = EFI_RT_SUPPORTED_ALL;
1059e9888a0SArd Biesheuvel
1069e9888a0SArd Biesheuvel rt_prop_table = get_efi_config_table(EFI_RT_PROPERTIES_TABLE_GUID);
1079e9888a0SArd Biesheuvel if (rt_prop_table)
1089e9888a0SArd Biesheuvel supported &= rt_prop_table->runtime_services_supported;
1099e9888a0SArd Biesheuvel
1109e9888a0SArd Biesheuvel return supported;
1119e9888a0SArd Biesheuvel }
1129e9888a0SArd Biesheuvel
efi_handle_cmdline(efi_loaded_image_t * image,char ** cmdline_ptr)113*42c8ea3dSArd Biesheuvel efi_status_t efi_handle_cmdline(efi_loaded_image_t *image, char **cmdline_ptr)
1142e0eb483SAtish Patra {
1152e0eb483SAtish Patra int cmdline_size = 0;
116*42c8ea3dSArd Biesheuvel efi_status_t status;
117*42c8ea3dSArd Biesheuvel char *cmdline;
1182e0eb483SAtish Patra
1192e0eb483SAtish Patra /*
1202e0eb483SAtish Patra * Get the command line from EFI, using the LOADED_IMAGE
1212e0eb483SAtish Patra * protocol. We are going to copy the command line into the
1222e0eb483SAtish Patra * device tree, so this can be allocated anywhere.
1232e0eb483SAtish Patra */
124*42c8ea3dSArd Biesheuvel cmdline = efi_convert_cmdline(image, &cmdline_size);
125*42c8ea3dSArd Biesheuvel if (!cmdline) {
126793473c2SArvind Sankar efi_err("getting command line via LOADED_IMAGE_PROTOCOL\n");
127*42c8ea3dSArd Biesheuvel return EFI_OUT_OF_RESOURCES;
1282e0eb483SAtish Patra }
1292e0eb483SAtish Patra
1302e0eb483SAtish Patra if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) ||
1312e0eb483SAtish Patra IS_ENABLED(CONFIG_CMDLINE_FORCE) ||
132055042beSArvind Sankar cmdline_size == 0) {
133055042beSArvind Sankar status = efi_parse_options(CONFIG_CMDLINE);
134055042beSArvind Sankar if (status != EFI_SUCCESS) {
135055042beSArvind Sankar efi_err("Failed to parse options\n");
136055042beSArvind Sankar goto fail_free_cmdline;
137055042beSArvind Sankar }
138055042beSArvind Sankar }
1392e0eb483SAtish Patra
140055042beSArvind Sankar if (!IS_ENABLED(CONFIG_CMDLINE_FORCE) && cmdline_size > 0) {
141*42c8ea3dSArd Biesheuvel status = efi_parse_options(cmdline);
142055042beSArvind Sankar if (status != EFI_SUCCESS) {
143055042beSArvind Sankar efi_err("Failed to parse options\n");
144055042beSArvind Sankar goto fail_free_cmdline;
145055042beSArvind Sankar }
146055042beSArvind Sankar }
1472e0eb483SAtish Patra
148*42c8ea3dSArd Biesheuvel *cmdline_ptr = cmdline;
149*42c8ea3dSArd Biesheuvel return EFI_SUCCESS;
150*42c8ea3dSArd Biesheuvel
151*42c8ea3dSArd Biesheuvel fail_free_cmdline:
152*42c8ea3dSArd Biesheuvel efi_bs_call(free_pool, cmdline_ptr);
153*42c8ea3dSArd Biesheuvel return status;
154*42c8ea3dSArd Biesheuvel }
155*42c8ea3dSArd Biesheuvel
efi_stub_common(efi_handle_t handle,efi_loaded_image_t * image,unsigned long image_addr,char * cmdline_ptr)156*42c8ea3dSArd Biesheuvel efi_status_t efi_stub_common(efi_handle_t handle,
157*42c8ea3dSArd Biesheuvel efi_loaded_image_t *image,
158*42c8ea3dSArd Biesheuvel unsigned long image_addr,
159*42c8ea3dSArd Biesheuvel char *cmdline_ptr)
160*42c8ea3dSArd Biesheuvel {
161*42c8ea3dSArd Biesheuvel struct screen_info *si;
162*42c8ea3dSArd Biesheuvel efi_status_t status;
163*42c8ea3dSArd Biesheuvel
164*42c8ea3dSArd Biesheuvel status = check_platform_features();
165*42c8ea3dSArd Biesheuvel if (status != EFI_SUCCESS)
166*42c8ea3dSArd Biesheuvel return status;
1672e0eb483SAtish Patra
1682e0eb483SAtish Patra si = setup_graphics();
1692e0eb483SAtish Patra
1702e0eb483SAtish Patra efi_retrieve_tpm2_eventlog();
1712e0eb483SAtish Patra
1722e0eb483SAtish Patra /* Ask the firmware to clear memory on unclean shutdown */
1732e0eb483SAtish Patra efi_enable_reset_attack_mitigation();
1742e0eb483SAtish Patra
175f4dc7fffSArd Biesheuvel efi_load_initrd(image, ULONG_MAX, efi_get_max_initrd_addr(image_addr),
176f4dc7fffSArd Biesheuvel NULL);
1772e0eb483SAtish Patra
1782e0eb483SAtish Patra efi_random_get_seed();
1792e0eb483SAtish Patra
1809e9888a0SArd Biesheuvel /* force efi_novamap if SetVirtualAddressMap() is unsupported */
1819e9888a0SArd Biesheuvel efi_novamap |= !(get_supported_rt_services() &
1829e9888a0SArd Biesheuvel EFI_RT_SUPPORTED_SET_VIRTUAL_ADDRESS_MAP);
1839e9888a0SArd Biesheuvel
1842e0eb483SAtish Patra install_memreserve_table();
1852e0eb483SAtish Patra
1864fc8e738SArd Biesheuvel status = efi_boot_kernel(handle, image, image_addr, cmdline_ptr);
1872e0eb483SAtish Patra
1882e0eb483SAtish Patra free_screen_info(si);
1892e0eb483SAtish Patra return status;
1902e0eb483SAtish Patra }
1912e0eb483SAtish Patra
1922e0eb483SAtish Patra /*
193f80d2604SArd Biesheuvel * efi_allocate_virtmap() - create a pool allocation for the virtmap
194f80d2604SArd Biesheuvel *
195f80d2604SArd Biesheuvel * Create an allocation that is of sufficient size to hold all the memory
196f80d2604SArd Biesheuvel * descriptors that will be passed to SetVirtualAddressMap() to inform the
197f80d2604SArd Biesheuvel * firmware about the virtual mapping that will be used under the OS to call
198f80d2604SArd Biesheuvel * into the firmware.
199f80d2604SArd Biesheuvel */
efi_alloc_virtmap(efi_memory_desc_t ** virtmap,unsigned long * desc_size,u32 * desc_ver)200f80d2604SArd Biesheuvel efi_status_t efi_alloc_virtmap(efi_memory_desc_t **virtmap,
201f80d2604SArd Biesheuvel unsigned long *desc_size, u32 *desc_ver)
202f80d2604SArd Biesheuvel {
203f80d2604SArd Biesheuvel unsigned long size, mmap_key;
204f80d2604SArd Biesheuvel efi_status_t status;
205f80d2604SArd Biesheuvel
206f80d2604SArd Biesheuvel /*
207f80d2604SArd Biesheuvel * Use the size of the current memory map as an upper bound for the
208f80d2604SArd Biesheuvel * size of the buffer we need to pass to SetVirtualAddressMap() to
209f80d2604SArd Biesheuvel * cover all EFI_MEMORY_RUNTIME regions.
210f80d2604SArd Biesheuvel */
211f80d2604SArd Biesheuvel size = 0;
212f80d2604SArd Biesheuvel status = efi_bs_call(get_memory_map, &size, NULL, &mmap_key, desc_size,
213f80d2604SArd Biesheuvel desc_ver);
214f80d2604SArd Biesheuvel if (status != EFI_BUFFER_TOO_SMALL)
215f80d2604SArd Biesheuvel return EFI_LOAD_ERROR;
216f80d2604SArd Biesheuvel
217f80d2604SArd Biesheuvel return efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
218f80d2604SArd Biesheuvel (void **)virtmap);
219f80d2604SArd Biesheuvel }
220f80d2604SArd Biesheuvel
221f80d2604SArd Biesheuvel /*
2222e0eb483SAtish Patra * efi_get_virtmap() - create a virtual mapping for the EFI memory map
2232e0eb483SAtish Patra *
2242e0eb483SAtish Patra * This function populates the virt_addr fields of all memory region descriptors
2252e0eb483SAtish Patra * in @memory_map whose EFI_MEMORY_RUNTIME attribute is set. Those descriptors
2262e0eb483SAtish Patra * are also copied to @runtime_map, and their total count is returned in @count.
2272e0eb483SAtish Patra */
efi_get_virtmap(efi_memory_desc_t * memory_map,unsigned long map_size,unsigned long desc_size,efi_memory_desc_t * runtime_map,int * count)2282e0eb483SAtish Patra void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
2292e0eb483SAtish Patra unsigned long desc_size, efi_memory_desc_t *runtime_map,
2302e0eb483SAtish Patra int *count)
2312e0eb483SAtish Patra {
2322e0eb483SAtish Patra u64 efi_virt_base = virtmap_base;
2332e0eb483SAtish Patra efi_memory_desc_t *in, *out = runtime_map;
2342e0eb483SAtish Patra int l;
2352e0eb483SAtish Patra
236f80d2604SArd Biesheuvel *count = 0;
237f80d2604SArd Biesheuvel
2382e0eb483SAtish Patra for (l = 0; l < map_size; l += desc_size) {
2392e0eb483SAtish Patra u64 paddr, size;
2402e0eb483SAtish Patra
2412e0eb483SAtish Patra in = (void *)memory_map + l;
2422e0eb483SAtish Patra if (!(in->attribute & EFI_MEMORY_RUNTIME))
2432e0eb483SAtish Patra continue;
2442e0eb483SAtish Patra
2452e0eb483SAtish Patra paddr = in->phys_addr;
2462e0eb483SAtish Patra size = in->num_pages * EFI_PAGE_SIZE;
2472e0eb483SAtish Patra
248ead384d9SHuacai Chen in->virt_addr = in->phys_addr + EFI_RT_VIRTUAL_OFFSET;
249980771f6SArd Biesheuvel if (efi_novamap) {
2502e0eb483SAtish Patra continue;
2512e0eb483SAtish Patra }
2522e0eb483SAtish Patra
2532e0eb483SAtish Patra /*
2542e0eb483SAtish Patra * Make the mapping compatible with 64k pages: this allows
2552e0eb483SAtish Patra * a 4k page size kernel to kexec a 64k page size kernel and
2562e0eb483SAtish Patra * vice versa.
2572e0eb483SAtish Patra */
2582e0eb483SAtish Patra if (!flat_va_mapping) {
2592e0eb483SAtish Patra
2602e0eb483SAtish Patra paddr = round_down(in->phys_addr, SZ_64K);
2612e0eb483SAtish Patra size += in->phys_addr - paddr;
2622e0eb483SAtish Patra
2632e0eb483SAtish Patra /*
2642e0eb483SAtish Patra * Avoid wasting memory on PTEs by choosing a virtual
2652e0eb483SAtish Patra * base that is compatible with section mappings if this
2662e0eb483SAtish Patra * region has the appropriate size and physical
2672e0eb483SAtish Patra * alignment. (Sections are 2 MB on 4k granule kernels)
2682e0eb483SAtish Patra */
2692e0eb483SAtish Patra if (IS_ALIGNED(in->phys_addr, SZ_2M) && size >= SZ_2M)
2702e0eb483SAtish Patra efi_virt_base = round_up(efi_virt_base, SZ_2M);
2712e0eb483SAtish Patra else
2722e0eb483SAtish Patra efi_virt_base = round_up(efi_virt_base, SZ_64K);
2732e0eb483SAtish Patra
2742e0eb483SAtish Patra in->virt_addr += efi_virt_base - paddr;
2752e0eb483SAtish Patra efi_virt_base += size;
2762e0eb483SAtish Patra }
2772e0eb483SAtish Patra
2782e0eb483SAtish Patra memcpy(out, in, desc_size);
2792e0eb483SAtish Patra out = (void *)out + desc_size;
2802e0eb483SAtish Patra ++*count;
2812e0eb483SAtish Patra }
2822e0eb483SAtish Patra }
283