freebsd-nq/lib/csu/riscv/crti.S
Ruslan Bukin af19cc59ca Support for v1.10 (latest) of RISC-V privilege specification.
New version is not compatible on supervisor mode with v1.9.1
(previous version).

Highlights:
    o BBL (Berkeley Boot Loader) provides no initial page tables
      anymore allowing us to choose VM, to build page tables manually
      and enable MMU in S-mode.
    o SBI interface changed.
    o GENERIC kernel.
      FDT is now chosen standard for RISC-V hardware description.
      DTB is now provided by Spike (golden model simulator). This
      allows us to introduce GENERIC kernel. However, description
      for console and timer devices is not provided in DTB, so move
      these devices temporary to nexus bus.
    o Supervisor can't access userspace by default. Solution is to
      set SUM (permit Supervisor User Memory access) bit in sstatus
      register.
    o Compressed extension is now turned on by default.
    o External GCC 7.1 compiler used.
    o _gp renamed to __global_pointer$
    o Compiler -march= string is now in use allowing us to choose
      required extensions (compressed, FPU, atomic, etc).

Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D11800
2017-08-10 14:18:09 +00:00

60 lines
2.2 KiB
ArmAsm

/*-
* Copyright (c) 2015-2017 Ruslan Bukin <br@bsdpad.com>
* All rights reserved.
*
* Portions of this software were developed by SRI International and the
* University of Cambridge Computer Laboratory under DARPA/AFRL contract
* FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme.
*
* Portions of this software were developed by the University of Cambridge
* Computer Laboratory as part of the CTSRD Project, with support from the
* UK Higher Education Innovation Fund (HEIF).
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <machine/asm.h>
__FBSDID("$FreeBSD$");
# this puts __global_pointer$ into .dynsym, so symlook_obj can now find that
# (see reloc.c)
.weak __global_pointer$
__global_pointer$:
.section .init,"ax",@progbits
.align 0
.globl _init
.type _init,@function
_init:
addi sp, sp, -16
sd ra, 0(sp)
.section .fini,"ax",@progbits
.align 0
.globl _fini
.type _fini,@function
_fini:
addi sp, sp, -16
sd ra, 0(sp)
.section .note.GNU-stack,"",%progbits