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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/firmware/efi/libstub/arm64.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/firmware/efi/libstub/arm64.c')
-rw-r--r-- | drivers/firmware/efi/libstub/arm64.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/drivers/firmware/efi/libstub/arm64.c b/drivers/firmware/efi/libstub/arm64.c new file mode 100644 index 0000000000..446e35eaf3 --- /dev/null +++ b/drivers/firmware/efi/libstub/arm64.c @@ -0,0 +1,140 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org> + * + * This file implements the EFI boot stub for the arm64 kernel. + * Adapted from ARM version by Mark Salter <msalter@redhat.com> + */ + + +#include <linux/efi.h> +#include <asm/efi.h> +#include <asm/image.h> +#include <asm/memory.h> +#include <asm/sysreg.h> + +#include "efistub.h" + +static bool system_needs_vamap(void) +{ + const struct efi_smbios_type4_record *record; + const u32 __aligned(1) *socid; + const u8 *version; + + /* + * Ampere eMAG, Altra, and Altra Max machines crash in SetTime() if + * SetVirtualAddressMap() has not been called prior. Most Altra systems + * can be identified by the SMCCC soc ID, which is conveniently exposed + * via the type 4 SMBIOS records. Otherwise, test the processor version + * field. eMAG systems all appear to have the processor version field + * set to "eMAG". + */ + record = (struct efi_smbios_type4_record *)efi_get_smbios_record(4); + if (!record) + return false; + + socid = (u32 *)record->processor_id; + switch (*socid & 0xffff000f) { + static char const altra[] = "Ampere(TM) Altra(TM) Processor"; + static char const emag[] = "eMAG"; + + default: + version = efi_get_smbios_string(&record->header, 4, + processor_version); + if (!version || (strncmp(version, altra, sizeof(altra) - 1) && + strncmp(version, emag, sizeof(emag) - 1))) + break; + + fallthrough; + + case 0x0a160001: // Altra + case 0x0a160002: // Altra Max + efi_warn("Working around broken SetVirtualAddressMap()\n"); + return true; + } + + return false; +} + +efi_status_t check_platform_features(void) +{ + u64 tg; + + /* + * If we have 48 bits of VA space for TTBR0 mappings, we can map the + * UEFI runtime regions 1:1 and so calling SetVirtualAddressMap() is + * unnecessary. + */ + if (VA_BITS_MIN >= 48 && !system_needs_vamap()) + efi_novamap = true; + + /* UEFI mandates support for 4 KB granularity, no need to check */ + if (IS_ENABLED(CONFIG_ARM64_4K_PAGES)) + return EFI_SUCCESS; + + tg = (read_cpuid(ID_AA64MMFR0_EL1) >> ID_AA64MMFR0_EL1_TGRAN_SHIFT) & 0xf; + if (tg < ID_AA64MMFR0_EL1_TGRAN_SUPPORTED_MIN || tg > ID_AA64MMFR0_EL1_TGRAN_SUPPORTED_MAX) { + if (IS_ENABLED(CONFIG_ARM64_64K_PAGES)) + efi_err("This 64 KB granular kernel is not supported by your CPU\n"); + else + efi_err("This 16 KB granular kernel is not supported by your CPU\n"); + return EFI_UNSUPPORTED; + } + return EFI_SUCCESS; +} + +#ifdef CONFIG_ARM64_WORKAROUND_CLEAN_CACHE +#define DCTYPE "civac" +#else +#define DCTYPE "cvau" +#endif + +u32 __weak code_size; + +void efi_cache_sync_image(unsigned long image_base, + unsigned long alloc_size) +{ + u32 ctr = read_cpuid_effective_cachetype(); + u64 lsize = 4 << cpuid_feature_extract_unsigned_field(ctr, + CTR_EL0_DminLine_SHIFT); + + /* only perform the cache maintenance if needed for I/D coherency */ + if (!(ctr & BIT(CTR_EL0_IDC_SHIFT))) { + unsigned long base = image_base; + unsigned long size = code_size; + + do { + asm("dc " DCTYPE ", %0" :: "r"(base)); + base += lsize; + size -= lsize; + } while (size >= lsize); + } + + asm("ic ialluis"); + dsb(ish); + isb(); + + efi_remap_image(image_base, alloc_size, code_size); +} + +unsigned long __weak primary_entry_offset(void) +{ + /* + * By default, we can invoke the kernel via the branch instruction in + * the image header, so offset #0. This will be overridden by the EFI + * stub build that is linked into the core kernel, as in that case, the + * image header may not have been loaded into memory, or may be mapped + * with non-executable permissions. + */ + return 0; +} + +void __noreturn efi_enter_kernel(unsigned long entrypoint, + unsigned long fdt_addr, + unsigned long fdt_size) +{ + void (* __noreturn enter_kernel)(u64, u64, u64, u64); + + enter_kernel = (void *)entrypoint + primary_entry_offset(); + enter_kernel(fdt_addr, 0, 0, 0); +} |