v4.19.13 snapshot.
diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
new file mode 100644
index 0000000..1b4d465
--- /dev/null
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -0,0 +1,159 @@
+/*
+ * 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>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+/*
+ * To prevent the compiler from emitting GOT-indirected (and thus absolute)
+ * references to the section markers, override their visibility as 'hidden'
+ */
+#pragma GCC visibility push(hidden)
+#include <asm/sections.h>
+#pragma GCC visibility pop
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+#include <asm/memory.h>
+#include <asm/sysreg.h>
+
+#include "efistub.h"
+
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
+{
+ u64 tg;
+
+ /* 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_TGRAN_SHIFT) & 0xf;
+ if (tg != ID_AA64MMFR0_TGRAN_SUPPORTED) {
+ if (IS_ENABLED(CONFIG_ARM64_64K_PAGES))
+ pr_efi_err(sys_table_arg, "This 64 KB granular kernel is not supported by your CPU\n");
+ else
+ pr_efi_err(sys_table_arg, "This 16 KB granular kernel is not supported by your CPU\n");
+ return EFI_UNSUPPORTED;
+ }
+ return EFI_SUCCESS;
+}
+
+efi_status_t handle_kernel_image(efi_system_table_t *sys_table_arg,
+ unsigned long *image_addr,
+ unsigned long *image_size,
+ unsigned long *reserve_addr,
+ unsigned long *reserve_size,
+ unsigned long dram_base,
+ efi_loaded_image_t *image)
+{
+ efi_status_t status;
+ unsigned long kernel_size, kernel_memsize = 0;
+ void *old_image_addr = (void *)*image_addr;
+ unsigned long preferred_offset;
+ u64 phys_seed = 0;
+
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+ if (!nokaslr()) {
+ status = efi_get_random_bytes(sys_table_arg,
+ sizeof(phys_seed),
+ (u8 *)&phys_seed);
+ if (status == EFI_NOT_FOUND) {
+ pr_efi(sys_table_arg, "EFI_RNG_PROTOCOL unavailable, no randomness supplied\n");
+ } else if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table_arg, "efi_get_random_bytes() failed\n");
+ return status;
+ }
+ } else {
+ pr_efi(sys_table_arg, "KASLR disabled on kernel command line\n");
+ }
+ }
+
+ /*
+ * The preferred offset of the kernel Image is TEXT_OFFSET bytes beyond
+ * a 2 MB aligned base, which itself may be lower than dram_base, as
+ * long as the resulting offset equals or exceeds it.
+ */
+ preferred_offset = round_down(dram_base, MIN_KIMG_ALIGN) + TEXT_OFFSET;
+ if (preferred_offset < dram_base)
+ preferred_offset += MIN_KIMG_ALIGN;
+
+ kernel_size = _edata - _text;
+ kernel_memsize = kernel_size + (_end - _edata);
+
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && phys_seed != 0) {
+ /*
+ * If CONFIG_DEBUG_ALIGN_RODATA is not set, produce a
+ * displacement in the interval [0, MIN_KIMG_ALIGN) that
+ * doesn't violate this kernel's de-facto alignment
+ * constraints.
+ */
+ u32 mask = (MIN_KIMG_ALIGN - 1) & ~(EFI_KIMG_ALIGN - 1);
+ u32 offset = !IS_ENABLED(CONFIG_DEBUG_ALIGN_RODATA) ?
+ (phys_seed >> 32) & mask : TEXT_OFFSET;
+
+ /*
+ * With CONFIG_RANDOMIZE_TEXT_OFFSET=y, TEXT_OFFSET may not
+ * be a multiple of EFI_KIMG_ALIGN, and we must ensure that
+ * we preserve the misalignment of 'offset' relative to
+ * EFI_KIMG_ALIGN so that statically allocated objects whose
+ * alignment exceeds PAGE_SIZE appear correctly aligned in
+ * memory.
+ */
+ offset |= TEXT_OFFSET % EFI_KIMG_ALIGN;
+
+ /*
+ * If KASLR is enabled, and we have some randomness available,
+ * locate the kernel at a randomized offset in physical memory.
+ */
+ *reserve_size = kernel_memsize + offset;
+ status = efi_random_alloc(sys_table_arg, *reserve_size,
+ MIN_KIMG_ALIGN, reserve_addr,
+ (u32)phys_seed);
+
+ *image_addr = *reserve_addr + offset;
+ } else {
+ /*
+ * Else, try a straight allocation at the preferred offset.
+ * This will work around the issue where, if dram_base == 0x0,
+ * efi_low_alloc() refuses to allocate at 0x0 (to prevent the
+ * address of the allocation to be mistaken for a FAIL return
+ * value or a NULL pointer). It will also ensure that, on
+ * platforms where the [dram_base, dram_base + TEXT_OFFSET)
+ * interval is partially occupied by the firmware (like on APM
+ * Mustang), we can still place the kernel at the address
+ * 'dram_base + TEXT_OFFSET'.
+ */
+ if (*image_addr == preferred_offset)
+ return EFI_SUCCESS;
+
+ *image_addr = *reserve_addr = preferred_offset;
+ *reserve_size = round_up(kernel_memsize, EFI_ALLOC_ALIGN);
+
+ status = efi_call_early(allocate_pages, EFI_ALLOCATE_ADDRESS,
+ EFI_LOADER_DATA,
+ *reserve_size / EFI_PAGE_SIZE,
+ (efi_physical_addr_t *)reserve_addr);
+ }
+
+ if (status != EFI_SUCCESS) {
+ *reserve_size = kernel_memsize + TEXT_OFFSET;
+ status = efi_low_alloc(sys_table_arg, *reserve_size,
+ MIN_KIMG_ALIGN, reserve_addr);
+
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table_arg, "Failed to relocate kernel\n");
+ *reserve_size = 0;
+ return status;
+ }
+ *image_addr = *reserve_addr + TEXT_OFFSET;
+ }
+ memcpy((void *)*image_addr, old_image_addr, kernel_size);
+
+ return EFI_SUCCESS;
+}