bsd-user/aarch64/target_syscall.h

   1 /*
   2  * ARM AArch64 specific CPU for bsd-user
   3  *
   4  * Copyright (c) 2015 Stacey D. Son <sson at Freebsd>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #ifndef BSD_USER_AARCH64_TARGET_SYSCALL_H
  21 #define BSD_USER_AARCH64_TARGET_SYSCALL_H
  22
  23 /*
  24  * The aarch64 registers are named:
  25  *
  26  * x0 through x30 - for 64-bit-wide access (same registers)
  27  * Register '31' is one of two registers depending on the instruction context:
  28  *  For instructions dealing with the stack, it is the stack pointer, named rsp
  29  *  For all other instructions, it is a "zero" register, which returns 0 when
  30  *  read and discards data when written - named rzr (xzr, wzr)
  31  *
  32  * Usage during syscall/function call:
  33  * r0-r7 are used for arguments and return values
  34  * For syscalls, the syscall number is in r8
  35  * r9-r15 are for temporary values (may get trampled)
  36  * r16-r18 are used for intra-procedure-call and platform values (avoid)
  37  * The called routine is expected to preserve r19-r28
  38  * r29 and r30 are used as the frame register and link register (avoid)
  39  * See the ARM Procedure Call Reference for details.
  40  */
  41 struct target_pt_regs {
  42     uint64_t    regs[31];
  43     uint64_t    sp;
  44     uint64_t    pc;
  45     uint64_t    pstate;
  46 };
  47
  48 #define TARGET_HW_MACHINE       "arm64"
  49 #define TARGET_HW_MACHINE_ARCH  "aarch64"
  50
  51 #endif /* BSD_USER_AARCH64_TARGET_SYSCALL_H */