riscv: Add EFI application infrastructure
The hello world binary and a few selftests require to build EFI target
binaries, not just the EFI host environment.
This patch adds all required files to generate an EFI binary for
RISC-V.
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/riscv/lib/crt0_riscv_efi.S b/arch/riscv/lib/crt0_riscv_efi.S
new file mode 100644
index 0000000..498870e
--- /dev/null
+++ b/arch/riscv/lib/crt0_riscv_efi.S
@@ -0,0 +1,152 @@
+/*
+ * crt0-efi-riscv.S - PE/COFF header for RISC-V EFI applications
+ *
+ * Copright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ * Copright (C) 2018 Alexander Graf <agraf@suse.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+ BSD-2-Clause
+ *
+ * This file is inspired by arch/arm/lib/crt0_aarch64_efi.S
+ */
+
+#include <asm-generic/pe.h>
+
+#if __riscv_xlen == 64
+#define SIZE_LONG 8
+#define SAVE_LONG(reg, idx) sd reg, (idx*SIZE_LONG)(sp)
+#define LOAD_LONG(reg, idx) ld reg, (idx*SIZE_LONG)(sp)
+#define PE_MACHINE 0x5064
+#else
+#define SIZE_LONG 4
+#define SAVE_LONG(reg, idx) sw reg, (idx*SIZE_LONG)(sp)
+#define LOAD_LONG(reg, idx) lw reg, (idx*SIZE_LONG)(sp)
+#define PE_MACHINE 0x5032
+#endif
+
+
+ .section .text.head
+
+ /*
+ * Magic "MZ" signature for PE/COFF
+ */
+ .globl ImageBase
+ImageBase:
+ .ascii "MZ"
+ .skip 58 /* 'MZ' + pad + offset == 64 */
+ .long pe_header - ImageBase /* Offset to the PE header */
+pe_header:
+ .ascii "PE"
+ .short 0
+coff_header:
+ .short PE_MACHINE /* RISC-V 64/32-bit */
+ .short 2 /* nr_sections */
+ .long 0 /* TimeDateStamp */
+ .long 0 /* PointerToSymbolTable */
+ .long 1 /* NumberOfSymbols */
+ .short section_table - optional_header /* SizeOfOptionalHeader */
+ /*
+ * Characteristics: IMAGE_FILE_DEBUG_STRIPPED |
+ * IMAGE_FILE_EXECUTABLE_IMAGE | IMAGE_FILE_LINE_NUMS_STRIPPED
+ */
+ .short 0x206
+optional_header:
+ .short 0x20b /* PE32+ format */
+ .byte 0x02 /* MajorLinkerVersion */
+ .byte 0x14 /* MinorLinkerVersion */
+ .long _edata - _start /* SizeOfCode */
+ .long 0 /* SizeOfInitializedData */
+ .long 0 /* SizeOfUninitializedData */
+ .long _start - ImageBase /* AddressOfEntryPoint */
+ .long _start - ImageBase /* 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 - ImageBase /* SizeOfImage */
+
+ /*
+ * Everything before the kernel image is considered part of the header
+ */
+ .long _start - ImageBase /* SizeOfHeaders */
+ .long 0 /* CheckSum */
+ .short IMAGE_SUBSYSTEM_EFI_APPLICATION /* Subsystem */
+ .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 - _start /* VirtualSize */
+ .long _start - ImageBase /* VirtualAddress */
+ .long _edata - _start /* SizeOfRawData */
+ .long _start - ImageBase /* 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) */
+
+_start:
+ addi sp, sp, -(SIZE_LONG * 3)
+ SAVE_LONG(a0, 0)
+ SAVE_LONG(a1, 1)
+ SAVE_LONG(ra, 2)
+
+ lla a0, ImageBase
+ lla a1, _DYNAMIC
+ call _relocate
+ bne a0, zero, 0f
+
+ LOAD_LONG(a1, 1)
+ LOAD_LONG(a0, 0)
+ call efi_main
+
+ LOAD_LONG(ra, 2)
+
+0: addi sp, sp, (SIZE_LONG * 3)
+ ret