1d9ffe524SArd Biesheuvel // SPDX-License-Identifier: GPL-2.0
2d9ffe524SArd Biesheuvel /*
3d9ffe524SArd Biesheuvel * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org>
4d9ffe524SArd Biesheuvel *
5d9ffe524SArd Biesheuvel * This file implements the EFI boot stub for the arm64 kernel.
6d9ffe524SArd Biesheuvel * Adapted from ARM version by Mark Salter <msalter@redhat.com>
7d9ffe524SArd Biesheuvel */
8d9ffe524SArd Biesheuvel
9d9ffe524SArd Biesheuvel
10d9ffe524SArd Biesheuvel #include <linux/efi.h>
11d9ffe524SArd Biesheuvel #include <asm/efi.h>
12*026b8579SArd Biesheuvel #include <asm/image.h>
13d9ffe524SArd Biesheuvel #include <asm/memory.h>
14d9ffe524SArd Biesheuvel #include <asm/sysreg.h>
15d9ffe524SArd Biesheuvel
16d9ffe524SArd Biesheuvel #include "efistub.h"
17d9ffe524SArd Biesheuvel
system_needs_vamap(void)1897712289SArd Biesheuvel static bool system_needs_vamap(void)
1997712289SArd Biesheuvel {
20eb684408SArd Biesheuvel const struct efi_smbios_type4_record *record;
21eb684408SArd Biesheuvel const u32 __aligned(1) *socid;
22eb684408SArd Biesheuvel const u8 *version;
2397712289SArd Biesheuvel
2497712289SArd Biesheuvel /*
2519023316SDarren Hart * Ampere eMAG, Altra, and Altra Max machines crash in SetTime() if
26eb684408SArd Biesheuvel * SetVirtualAddressMap() has not been called prior. Most Altra systems
27eb684408SArd Biesheuvel * can be identified by the SMCCC soc ID, which is conveniently exposed
28eb684408SArd Biesheuvel * via the type 4 SMBIOS records. Otherwise, test the processor version
29eb684408SArd Biesheuvel * field. eMAG systems all appear to have the processor version field
30eb684408SArd Biesheuvel * set to "eMAG".
3197712289SArd Biesheuvel */
32eb684408SArd Biesheuvel record = (struct efi_smbios_type4_record *)efi_get_smbios_record(4);
33eb684408SArd Biesheuvel if (!record)
3497712289SArd Biesheuvel return false;
3597712289SArd Biesheuvel
36eb684408SArd Biesheuvel socid = (u32 *)record->processor_id;
37eb684408SArd Biesheuvel switch (*socid & 0xffff000f) {
38eb684408SArd Biesheuvel static char const altra[] = "Ampere(TM) Altra(TM) Processor";
39eb684408SArd Biesheuvel static char const emag[] = "eMAG";
40eb684408SArd Biesheuvel
41eb684408SArd Biesheuvel default:
42eb684408SArd Biesheuvel version = efi_get_smbios_string(&record->header, 4,
43eb684408SArd Biesheuvel processor_version);
44eb684408SArd Biesheuvel if (!version || (strncmp(version, altra, sizeof(altra) - 1) &&
45eb684408SArd Biesheuvel strncmp(version, emag, sizeof(emag) - 1)))
46eb684408SArd Biesheuvel break;
47eb684408SArd Biesheuvel
48eb684408SArd Biesheuvel fallthrough;
49eb684408SArd Biesheuvel
50eb684408SArd Biesheuvel case 0x0a160001: // Altra
51eb684408SArd Biesheuvel case 0x0a160002: // Altra Max
5297712289SArd Biesheuvel efi_warn("Working around broken SetVirtualAddressMap()\n");
5397712289SArd Biesheuvel return true;
5497712289SArd Biesheuvel }
5597712289SArd Biesheuvel
56eb684408SArd Biesheuvel return false;
57eb684408SArd Biesheuvel }
58eb684408SArd Biesheuvel
check_platform_features(void)59d9ffe524SArd Biesheuvel efi_status_t check_platform_features(void)
60d9ffe524SArd Biesheuvel {
61d9ffe524SArd Biesheuvel u64 tg;
62d9ffe524SArd Biesheuvel
63d9ffe524SArd Biesheuvel /*
64d9ffe524SArd Biesheuvel * If we have 48 bits of VA space for TTBR0 mappings, we can map the
65d9ffe524SArd Biesheuvel * UEFI runtime regions 1:1 and so calling SetVirtualAddressMap() is
66d9ffe524SArd Biesheuvel * unnecessary.
67d9ffe524SArd Biesheuvel */
6897712289SArd Biesheuvel if (VA_BITS_MIN >= 48 && !system_needs_vamap())
69d9ffe524SArd Biesheuvel efi_novamap = true;
70d9ffe524SArd Biesheuvel
71d9ffe524SArd Biesheuvel /* UEFI mandates support for 4 KB granularity, no need to check */
72d9ffe524SArd Biesheuvel if (IS_ENABLED(CONFIG_ARM64_4K_PAGES))
73d9ffe524SArd Biesheuvel return EFI_SUCCESS;
74d9ffe524SArd Biesheuvel
75d9ffe524SArd Biesheuvel tg = (read_cpuid(ID_AA64MMFR0_EL1) >> ID_AA64MMFR0_EL1_TGRAN_SHIFT) & 0xf;
76d9ffe524SArd Biesheuvel if (tg < ID_AA64MMFR0_EL1_TGRAN_SUPPORTED_MIN || tg > ID_AA64MMFR0_EL1_TGRAN_SUPPORTED_MAX) {
77d9ffe524SArd Biesheuvel if (IS_ENABLED(CONFIG_ARM64_64K_PAGES))
78d9ffe524SArd Biesheuvel efi_err("This 64 KB granular kernel is not supported by your CPU\n");
79d9ffe524SArd Biesheuvel else
80d9ffe524SArd Biesheuvel efi_err("This 16 KB granular kernel is not supported by your CPU\n");
81d9ffe524SArd Biesheuvel return EFI_UNSUPPORTED;
82d9ffe524SArd Biesheuvel }
83d9ffe524SArd Biesheuvel return EFI_SUCCESS;
84d9ffe524SArd Biesheuvel }
85d9ffe524SArd Biesheuvel
8661786170SArd Biesheuvel #ifdef CONFIG_ARM64_WORKAROUND_CLEAN_CACHE
8761786170SArd Biesheuvel #define DCTYPE "civac"
8861786170SArd Biesheuvel #else
8961786170SArd Biesheuvel #define DCTYPE "cvau"
9061786170SArd Biesheuvel #endif
9161786170SArd Biesheuvel
92*026b8579SArd Biesheuvel u32 __weak code_size;
93*026b8579SArd Biesheuvel
efi_cache_sync_image(unsigned long image_base,unsigned long alloc_size)94d9ffe524SArd Biesheuvel void efi_cache_sync_image(unsigned long image_base,
95*026b8579SArd Biesheuvel unsigned long alloc_size)
96d9ffe524SArd Biesheuvel {
97d9ffe524SArd Biesheuvel u32 ctr = read_cpuid_effective_cachetype();
98d9ffe524SArd Biesheuvel u64 lsize = 4 << cpuid_feature_extract_unsigned_field(ctr,
99d9ffe524SArd Biesheuvel CTR_EL0_DminLine_SHIFT);
100d9ffe524SArd Biesheuvel
10161786170SArd Biesheuvel /* only perform the cache maintenance if needed for I/D coherency */
10261786170SArd Biesheuvel if (!(ctr & BIT(CTR_EL0_IDC_SHIFT))) {
103*026b8579SArd Biesheuvel unsigned long base = image_base;
104*026b8579SArd Biesheuvel unsigned long size = code_size;
105*026b8579SArd Biesheuvel
106d9ffe524SArd Biesheuvel do {
107*026b8579SArd Biesheuvel asm("dc " DCTYPE ", %0" :: "r"(base));
108*026b8579SArd Biesheuvel base += lsize;
109*026b8579SArd Biesheuvel size -= lsize;
110*026b8579SArd Biesheuvel } while (size >= lsize);
11161786170SArd Biesheuvel }
112d9ffe524SArd Biesheuvel
113d9ffe524SArd Biesheuvel asm("ic ialluis");
114d9ffe524SArd Biesheuvel dsb(ish);
115d9ffe524SArd Biesheuvel isb();
116*026b8579SArd Biesheuvel
117*026b8579SArd Biesheuvel efi_remap_image(image_base, alloc_size, code_size);
118d9ffe524SArd Biesheuvel }
11961786170SArd Biesheuvel
primary_entry_offset(void)12061786170SArd Biesheuvel unsigned long __weak primary_entry_offset(void)
12161786170SArd Biesheuvel {
12261786170SArd Biesheuvel /*
12361786170SArd Biesheuvel * By default, we can invoke the kernel via the branch instruction in
12461786170SArd Biesheuvel * the image header, so offset #0. This will be overridden by the EFI
12561786170SArd Biesheuvel * stub build that is linked into the core kernel, as in that case, the
12661786170SArd Biesheuvel * image header may not have been loaded into memory, or may be mapped
12761786170SArd Biesheuvel * with non-executable permissions.
12861786170SArd Biesheuvel */
12961786170SArd Biesheuvel return 0;
13061786170SArd Biesheuvel }
13161786170SArd Biesheuvel
efi_enter_kernel(unsigned long entrypoint,unsigned long fdt_addr,unsigned long fdt_size)13261786170SArd Biesheuvel void __noreturn efi_enter_kernel(unsigned long entrypoint,
13361786170SArd Biesheuvel unsigned long fdt_addr,
13461786170SArd Biesheuvel unsigned long fdt_size)
13561786170SArd Biesheuvel {
13661786170SArd Biesheuvel void (* __noreturn enter_kernel)(u64, u64, u64, u64);
13761786170SArd Biesheuvel
13861786170SArd Biesheuvel enter_kernel = (void *)entrypoint + primary_entry_offset();
13961786170SArd Biesheuvel enter_kernel(fdt_addr, 0, 0, 0);
14061786170SArd Biesheuvel }
141