bsd-user: Add RISC-V ELF definitions and hardware capability detection

Introduced RISC-V specific ELF definitions and hardware capability
detection.
Additionally, a function to retrieve hardware capabilities
('get_elf_hwcap') is implemented, which returns the common bits set in
each CPU's ISA strings.

Signed-off-by: Mark Corbin <mark@dibsco.co.uk>
Signed-off-by: Ajeet Singh <itachis@FreeBSD.org>
Co-authored-by: Kyle Evans <kevans@FreeBSD.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20240916155119.14610-6-itachis@FreeBSD.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

bsd-user/riscv/target_arch_elf.h

@@ -0,0 +1,42 @@
+/*
+ *  RISC-V ELF definitions
+ *
+ *  Copyright (c) 2019 Mark Corbin
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TARGET_ARCH_ELF_H
+#define TARGET_ARCH_ELF_H
+
+#define elf_check_arch(x) ((x) == EM_RISCV)
+#define ELF_START_MMAP 0x80000000
+#define ELF_ET_DYN_LOAD_ADDR    0x100000
+#define ELF_CLASS   ELFCLASS64
+
+#define ELF_DATA    ELFDATA2LSB
+#define ELF_ARCH    EM_RISCV
+
+#define ELF_HWCAP get_elf_hwcap()
+static uint32_t get_elf_hwcap(void)
+{
+    RISCVCPU *cpu = RISCV_CPU(thread_cpu);
+
+    return cpu->env.misa_ext_mask;
+}
+
+#define USE_ELF_CORE_DUMP
+#define ELF_EXEC_PAGESIZE        4096
+
+#endif /* TARGET_ARCH_ELF_H */