@@ -280,6 +280,20 @@ config CMDLINE_FORCE
This is useful if you cannot or don't want to change the
command-line options your boot loader passes to the kernel.
+config EFI
+ bool "UEFI firmware support"
+ depends on OF
+ select LIBFDT
+ default y
+ help
+ This option permits an Image to be loaded directly
+ by EFI firmware without the use of a bootloader.
+ See Documentation/efi-stub.txt for more information.
+
+ This is only useful on systems that have UEFI firmware.
+ However, even with this option, the resultant kernel should
+ continue to boot on existing non-UEFI platforms.
+
endmenu
menu "Userspace binary formats"
@@ -4,6 +4,8 @@
CPPFLAGS_vmlinux.lds := -DTEXT_OFFSET=$(TEXT_OFFSET)
AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
+CFLAGS_efi-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) \
+ -I$(src)/../../../scripts/dtc/libfdt
# Object file lists.
arm64-obj-y := cputable.o debug-monitors.o entry.o irq.o fpsimd.o \
@@ -22,6 +24,7 @@ arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o
arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o
arm64-obj-$(CONFIG_KGDB) += kgdb.o
+arm64-obj-$(CONFIG_EFI) += efi-stub.o efi-entry.o
obj-y += $(arm64-obj-y) vdso/
obj-m += $(arm64-obj-m)
new file mode 100644
@@ -0,0 +1,100 @@
+/*
+ * EFI entry point.
+ *
+ * Copyright (C) 2013, 2014 Red Hat, Inc.
+ * Author: 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.
+ *
+ */
+#include <linux/linkage.h>
+#include <linux/init.h>
+
+#include <asm/assembler.h>
+
+#define EFI_LOAD_ERROR 0x8000000000000001
+
+ __INIT
+
+ /*
+ * We arrive here from the EFI boot manager with:
+ *
+ * * MMU on with identity-mapped RAM.
+ * * Icache and Dcache on
+ *
+ * We will most likely be running from some place other than where
+ * we want to be. The kernel image wants to be placed at TEXT_OFFSET
+ * from start of RAM.
+ */
+ENTRY(efi_stub_entry)
+ stp x29, x30, [sp, #-32]!
+
+ /*
+ * Call efi_entry to do the real work.
+ * x0 and x1 are already set up by firmware. Current runtime
+ * address of image is calculated and passed via *image_addr.
+ *
+ * unsigned long efi_entry(void *handle,
+ * efi_system_table_t *sys_table,
+ * unsigned long *image_addr) ;
+ */
+ adrp x8, _text
+ add x8, x8, #:lo12:_text
+ add x2, sp, 16
+ str x8, [x2]
+ bl efi_entry
+ cmn x0, #1
+ b.eq efi_load_fail
+
+ /*
+ * efi_entry() will have relocated the kernel image if necessary
+ * and we return here with device tree address in x0 and the kernel
+ * entry point stored at *image_addr. Save those values in registers
+ * which are callee preserved.
+ */
+ mov x20, x0 // DTB address
+ ldr x0, [sp, #16] // relocated _text address
+ mov x21, x0
+
+ adrp x1, _text
+ add x1, x1, #:lo12:_text
+ adrp x2, _edata
+ add x2, x2, #:lo12:_edata
+ sub x1, x2, x1
+
+ bl __flush_dcache_area
+ ic ialluis
+
+ /* Turn off Dcache and MMU */
+ mrs x0, CurrentEL
+ cmp x0, #PSR_MODE_EL2t
+ ccmp x0, #PSR_MODE_EL2h, #0x4, ne
+ b.ne 1f
+ mrs x0, sctlr_el2
+ bic x0, x0, #1 << 0 // clear SCTLR.M
+ bic x0, x0, #1 << 2 // clear SCTLR.C
+ msr sctlr_el2, x0
+ isb
+ b 2f
+1:
+ mrs x0, sctlr_el1
+ bic x0, x0, #1 << 0 // clear SCTLR.M
+ bic x0, x0, #1 << 2 // clear SCTLR.C
+ msr sctlr_el1, x0
+ isb
+2:
+ /* Jump to real entry point */
+ mov x0, x20
+ mov x1, xzr
+ mov x2, xzr
+ mov x3, xzr
+ br x21
+
+efi_load_fail:
+ mov x0, #EFI_LOAD_ERROR
+ ldp x29, x30, [sp], #32
+ ret
+
+ENDPROC(efi_stub_entry)
new file mode 100644
@@ -0,0 +1,97 @@
+/*
+ * 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.
+ *
+ */
+#include <linux/efi.h>
+#include <linux/libfdt.h>
+#include <asm/sections.h>
+#include <generated/compile.h>
+#include <generated/utsrelease.h>
+
+/*
+ * EFI function call wrappers. These are not required for arm/arm64, but
+ * wrappers are required for X86 to convert between ABIs. These wrappers are
+ * provided to allow code sharing between X86 and other architectures. Since
+ * these wrappers directly invoke the EFI function pointer, the function
+ * pointer type must be properly defined, which is not the case for X86. One
+ * advantage of this is it allows for type checking of arguments, which is not
+ * possible with the X86 wrappers.
+ */
+#define efi_call_phys0(f) f()
+#define efi_call_phys1(f, a1) f(a1)
+#define efi_call_phys2(f, a1, a2) f(a1, a2)
+#define efi_call_phys3(f, a1, a2, a3) f(a1, a2, a3)
+#define efi_call_phys4(f, a1, a2, a3, a4) f(a1, a2, a3, a4)
+#define efi_call_phys5(f, a1, a2, a3, a4, a5) f(a1, a2, a3, a4, a5)
+
+/*
+ * AArch64 requires the DTB to be 8-byte aligned in the first 512MiB from
+ * start of kernel and may not cross a 2MiB boundary. We set alignment to
+ * 2MiB so we know it won't cross a 2MiB boundary.
+ */
+#define EFI_FDT_ALIGN SZ_2M /* used by allocate_new_fdt_and_exit_boot() */
+#define MAX_FDT_OFFSET SZ_512M
+
+#define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__)
+
+static void efi_char16_printk(efi_system_table_t *sys_table_arg,
+ efi_char16_t *str);
+
+static efi_status_t efi_open_volume(efi_system_table_t *sys_table,
+ void *__image, void **__fh);
+static efi_status_t efi_file_close(void *__fh, void *handle);
+
+static efi_status_t
+efi_file_read(void *__fh, void *handle, unsigned long *size, void *addr);
+
+static efi_status_t
+efi_file_size(efi_system_table_t *sys_table, void *__fh,
+ efi_char16_t *filename_16, void **handle, u64 *file_sz);
+
+/* Include shared EFI stub code */
+#include "../../../drivers/firmware/efi/efi-stub-helper.c"
+#include "../../../drivers/firmware/efi/fdt.c"
+#include "../../../drivers/firmware/efi/arm-stub.c"
+
+
+static efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
+ 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;
+
+ /* Relocate the image, if required. */
+ kernel_size = _edata - _text;
+ if (*image_addr != (dram_base + TEXT_OFFSET)) {
+ kernel_memsize = kernel_size + (_end - _edata);
+ status = efi_relocate_kernel(sys_table, image_addr,
+ kernel_size, kernel_memsize,
+ dram_base + TEXT_OFFSET,
+ PAGE_SIZE);
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table, "Failed to relocate kernel\n");
+ return status;
+ }
+ if (*image_addr != (dram_base + TEXT_OFFSET)) {
+ pr_efi_err(sys_table, "Failed to alloc kernel memory\n");
+ efi_free(sys_table, kernel_memsize, *image_addr);
+ return EFI_ERROR;
+ }
+ *image_size = kernel_memsize;
+ }
+
+
+ return EFI_SUCCESS;
+}
@@ -107,8 +107,18 @@
/*
* DO NOT MODIFY. Image header expected by Linux boot-loaders.
*/
+#ifdef CONFIG_EFI
+ /*
+ * Magic "MZ" signature for PE/COFF
+ * Little Endian: add x13, x18, #0x16
+ */
+efi_head:
+ .long 0x91005a4d
+ b stext
+#else
b stext // branch to kernel start, magic
.long 0 // reserved
+#endif
.quad TEXT_OFFSET // Image load offset from start of RAM
.quad 0 // reserved
.quad 0 // reserved
@@ -119,7 +129,109 @@
.byte 0x52
.byte 0x4d
.byte 0x64
+#ifdef CONFIG_EFI
+ .long pe_header - efi_head // Offset to the PE header.
+#else
.word 0 // reserved
+#endif
+
+#ifdef CONFIG_EFI
+ .align 3
+pe_header:
+ .ascii "PE"
+ .short 0
+coff_header:
+ .short 0xaa64 // AArch64
+ .short 2 // nr_sections
+ .long 0 // TimeDateStamp
+ .long 0 // PointerToSymbolTable
+ .long 1 // NumberOfSymbols
+ .short section_table - optional_header // SizeOfOptionalHeader
+ .short 0x206 // Characteristics.
+ // IMAGE_FILE_DEBUG_STRIPPED |
+ // IMAGE_FILE_EXECUTABLE_IMAGE |
+ // IMAGE_FILE_LINE_NUMS_STRIPPED
+optional_header:
+ .short 0x20b // PE32+ format
+ .byte 0x02 // MajorLinkerVersion
+ .byte 0x14 // MinorLinkerVersion
+ .long _edata - stext // SizeOfCode
+ .long 0 // SizeOfInitializedData
+ .long 0 // SizeOfUninitializedData
+ .long efi_stub_entry - efi_head // AddressOfEntryPoint
+ .long stext - efi_head // BaseOfCode
+
+extra_header_fields:
+ .quad 0 // ImageBase
+ .long 0x20 // SectionAlignment
+ .long 0x8 // FileAlignment
+ .short 0 // MajorOperatingSystemVersion
+ .short 0 // MinorOperatingSystemVersion
+ .short 0 // MajorImageVersion
+ .short 0 // MinorImageVersion
+ .short 0 // MajorSubsystemVersion
+ .short 0 // MinorSubsystemVersion
+ .long 0 // Win32VersionValue
+
+ .long _edata - efi_head // SizeOfImage
+
+ // Everything before the kernel image is considered part of the header
+ .long stext - efi_head // SizeOfHeaders
+ .long 0 // CheckSum
+ .short 0xa // Subsystem (EFI application)
+ .short 0 // DllCharacteristics
+ .quad 0 // SizeOfStackReserve
+ .quad 0 // SizeOfStackCommit
+ .quad 0 // SizeOfHeapReserve
+ .quad 0 // SizeOfHeapCommit
+ .long 0 // LoaderFlags
+ .long 0x6 // NumberOfRvaAndSizes
+
+ .quad 0 // ExportTable
+ .quad 0 // ImportTable
+ .quad 0 // ResourceTable
+ .quad 0 // ExceptionTable
+ .quad 0 // CertificationTable
+ .quad 0 // BaseRelocationTable
+
+ // Section table
+section_table:
+
+ /*
+ * The EFI application loader requires a relocation section
+ * because EFI applications must be relocatable. This is a
+ * dummy section as far as we are concerned.
+ */
+ .ascii ".reloc"
+ .byte 0
+ .byte 0 // end of 0 padding of section name
+ .long 0
+ .long 0
+ .long 0 // SizeOfRawData
+ .long 0 // PointerToRawData
+ .long 0 // PointerToRelocations
+ .long 0 // PointerToLineNumbers
+ .short 0 // NumberOfRelocations
+ .short 0 // NumberOfLineNumbers
+ .long 0x42100040 // Characteristics (section flags)
+
+
+ .ascii ".text"
+ .byte 0
+ .byte 0
+ .byte 0 // end of 0 padding of section name
+ .long _edata - stext // VirtualSize
+ .long stext - efi_head // VirtualAddress
+ .long _edata - stext // SizeOfRawData
+ .long stext - efi_head // PointerToRawData
+
+ .long 0 // PointerToRelocations (0 for executables)
+ .long 0 // PointerToLineNumbers (0 for executables)
+ .short 0 // NumberOfRelocations (0 for executables)
+ .short 0 // NumberOfLineNumbers (0 for executables)
+ .long 0xe0500020 // Characteristics (section flags)
+ .align 5
+#endif
ENTRY(stext)
mov x21, x0 // x21=FDT
new file mode 100644
@@ -0,0 +1,248 @@
+/*
+ * EFI stub implementation that is shared by arm and arm64 architectures.
+ * This should be #included by the EFI stub implementation files.
+ *
+ * Copyright (C) 2013,2014 Linaro Limited
+ * Roy Franz <roy.franz@linaro.org
+ * Copyright (C) 2013 Red Hat, Inc.
+ * Mark Salter <msalter@redhat.com>
+ *
+ * This file is part of the Linux kernel, and is made available under the
+ * terms of the GNU General Public License version 2.
+ *
+ */
+
+
+static efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg,
+ void *__image, void **__fh)
+{
+ efi_file_io_interface_t *io;
+ efi_loaded_image_t *image = __image;
+ efi_file_handle_t *fh;
+ efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+ efi_status_t status;
+ void *handle = (void *)(unsigned long)image->device_handle;
+
+ status = sys_table_arg->boottime->handle_protocol(handle,
+ &fs_proto, (void **)&io);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to handle fs_proto\n");
+ return status;
+ }
+
+ status = io->open_volume(io, &fh);
+ if (status != EFI_SUCCESS)
+ efi_printk(sys_table_arg, "Failed to open volume\n");
+
+ *__fh = fh;
+ return status;
+}
+static efi_status_t efi_file_close(void *__fh, void *handle)
+{
+ efi_file_handle_t *fh = __fh;
+
+ return fh->close(handle);
+}
+
+static efi_status_t
+efi_file_read(void *__fh, void *handle, unsigned long *size, void *addr)
+{
+ efi_file_handle_t *fh = __fh;
+
+ return fh->read(handle, size, addr);
+}
+
+
+static efi_status_t
+efi_file_size(efi_system_table_t *sys_table_arg, void *__fh,
+ efi_char16_t *filename_16, void **handle, u64 *file_sz)
+{
+ efi_file_handle_t *h, *fh = __fh;
+ efi_file_info_t *info;
+ efi_status_t status;
+ efi_guid_t info_guid = EFI_FILE_INFO_ID;
+ unsigned long info_sz;
+
+ status = fh->open(fh, &h, filename_16, EFI_FILE_MODE_READ, (u64)0);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to open file: ");
+ efi_char16_printk(sys_table_arg, filename_16);
+ efi_printk(sys_table_arg, "\n");
+ return status;
+ }
+
+ *handle = h;
+
+ info_sz = 0;
+ status = h->get_info(h, &info_guid, &info_sz, NULL);
+ if (status != EFI_BUFFER_TOO_SMALL) {
+ efi_printk(sys_table_arg, "Failed to get file info size\n");
+ return status;
+ }
+
+grow:
+ status = sys_table_arg->boottime->allocate_pool(EFI_LOADER_DATA,
+ info_sz, (void **)&info);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to alloc mem for file info\n");
+ return status;
+ }
+
+ status = h->get_info(h, &info_guid, &info_sz,
+ info);
+ if (status == EFI_BUFFER_TOO_SMALL) {
+ sys_table_arg->boottime->free_pool(info);
+ goto grow;
+ }
+
+ *file_sz = info->file_size;
+ sys_table_arg->boottime->free_pool(info);
+
+ if (status != EFI_SUCCESS)
+ efi_printk(sys_table_arg, "Failed to get initrd info\n");
+
+ return status;
+}
+
+
+
+static void efi_char16_printk(efi_system_table_t *sys_table_arg,
+ efi_char16_t *str)
+{
+ struct efi_simple_text_output_protocol *out;
+
+ out = (struct efi_simple_text_output_protocol *)sys_table_arg->con_out;
+ efi_call_phys2(out->output_string, out, str);
+}
+
+
+/*
+ * This function handles the architcture specific differences between arm and
+ * arm64 regarding where the kernel image must be loaded and any memory that
+ * must be reserved. On failure it is required to free all
+ * all allocations it has made.
+ */
+static efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
+ 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 entry point for the arm/arm64 EFI stubs. This is the entrypoint
+ * that is described in the PE/COFF header. Most of the code is the same
+ * for both archictectures, with the arch-specific code provided in the
+ * handle_kernel_image() function.
+ */
+unsigned long __init efi_entry(void *handle, efi_system_table_t *sys_table,
+ unsigned long *image_addr)
+{
+ efi_loaded_image_t *image;
+ efi_status_t status;
+ unsigned long image_size = 0;
+ unsigned long dram_base;
+ /* addr/point and size pairs for memory management*/
+ unsigned long initrd_addr;
+ u64 initrd_size = 0;
+ unsigned long fdt_addr; /* Original DTB */
+ u64 fdt_size = 0; /* We don't get size from configuration table */
+ char *cmdline_ptr = NULL;
+ int cmdline_size = 0;
+ unsigned long new_fdt_addr;
+ efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
+ unsigned long reserve_addr = 0;
+ unsigned long reserve_size = 0;
+
+ /* Check if we were booted by the EFI firmware */
+ if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
+ goto fail;
+
+ pr_efi(sys_table, "Booting Linux Kernel...\n");
+
+ /*
+ * Get a handle to the loaded image protocol. This is used to get
+ * information about the running image, such as size and the command
+ * line.
+ */
+ status = efi_call_phys3(sys_table->boottime->handle_protocol,
+ handle, &loaded_image_proto, (void *)&image);
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table, "Failed to get loaded image protocol\n");
+ goto fail;
+ }
+
+ dram_base = get_dram_base(sys_table);
+ if (dram_base == EFI_ERROR) {
+ pr_efi_err(sys_table, "Failed to find DRAM base\n");
+ goto fail;
+ }
+ status = handle_kernel_image(sys_table, image_addr, &image_size,
+ &reserve_addr,
+ &reserve_size,
+ dram_base, image);
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table, "Failed to relocate kernel\n");
+ goto fail;
+ }
+
+ /*
+ * Get the command line from EFI, using the LOADED_IMAGE
+ * protocol. We are going to copy the command line into the
+ * device tree, so this can be allocated anywhere.
+ */
+ cmdline_ptr = efi_convert_cmdline(sys_table, image, &cmdline_size);
+ if (!cmdline_ptr) {
+ pr_efi_err(sys_table, "getting command line via LOADED_IMAGE_PROTOCOL\n");
+ goto fail_free_image;
+ }
+
+ /* Load a device tree from the configuration table, if present. */
+ fdt_addr = (uintptr_t)get_fdt(sys_table);
+ if (!fdt_addr) {
+ status = handle_cmdline_files(sys_table, image, cmdline_ptr,
+ "dtb=",
+ ~0UL, (unsigned long *)&fdt_addr,
+ (unsigned long *)&fdt_size);
+
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table, "Failed to load device tree!\n");
+ goto fail_free_cmdline;
+ }
+ }
+
+ status = handle_cmdline_files(sys_table, image, cmdline_ptr,
+ "initrd=", dram_base + SZ_512M,
+ (unsigned long *)&initrd_addr,
+ (unsigned long *)&initrd_size);
+ if (status != EFI_SUCCESS)
+ pr_efi_err(sys_table, "Failed initrd from command line!\n");
+
+ new_fdt_addr = fdt_addr;
+ status = allocate_new_fdt_and_exit_boot(sys_table, handle,
+ &new_fdt_addr, dram_base + MAX_FDT_OFFSET,
+ initrd_addr, initrd_size, cmdline_ptr,
+ fdt_addr, fdt_size);
+
+ /*
+ * If all went well, we need to return the FDT address to the
+ * calling function so it can be passed to kernel as part of
+ * the kernel boot protocol.
+ */
+ if (status == EFI_SUCCESS)
+ return new_fdt_addr;
+
+ pr_efi_err(sys_table, "Failed to update FDT and exit boot services\n");
+
+ efi_free(sys_table, initrd_size, initrd_addr);
+ efi_free(sys_table, fdt_size, fdt_addr);
+
+fail_free_cmdline:
+ efi_free(sys_table, cmdline_size, (unsigned long)cmdline_ptr);
+
+fail_free_image:
+ efi_free(sys_table, image_size, *image_addr);
+ efi_free(sys_table, reserve_size, reserve_addr);
+fail:
+ return EFI_ERROR;
+}