[PATCH 05/23] Managing CPU register for BSD-USER

[Ajeet Singh <itachis6234@gmail.com>]

From: Stacey Son <sson@FreeBSD.org>

Added structure for storing register states

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Ajeet Singh <itachis@FreeBSD.org>
Co-authored-by: Sean Bruno <sbruno@freebsd.org>
---
 bsd-user/aarch64/target_syscall.h | 51 +++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 bsd-user/aarch64/target_syscall.h

diff --git a/bsd-user/aarch64/target_syscall.h b/bsd-user/aarch64/target_syscall.h
new file mode 100644
index 0000000000..08ae913c42
--- /dev/null
+++ b/bsd-user/aarch64/target_syscall.h
@@ -0,0 +1,51 @@
+/*
+ * ARM AArch64 specific CPU for bsd-user
+ *
+ * Copyright (c) 2015 Stacey D. Son <sson at Freebsd>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef BSD_USER_AARCH64_TARGET_SYSCALL_H
+#define BSD_USER_AARCH64_TARGET_SYSCALL_H
+
+/*
+ * The aarch64 registers are named:
+ *
+ * x0 through x30 - for 64-bit-wide access (same registers)
+ * Register '31' is one of two registers depending on the instruction context:
+ *  For instructions dealing with the stack, it is the stack pointer, named rsp
+ *  For all other instructions, it is a "zero" register, which returns 0 when
+ *  read and discards data when written - named rzr (xzr, wzr)
+ *
+ * Usage during syscall/function call:
+ * r0-r7 are used for arguments and return values
+ * For syscalls, the syscall number is in r8
+ * r9-r15 are for temporary values (may get trampled)
+ * r16-r18 are used for intra-procedure-call and platform values (avoid)
+ * The called routine is expected to preserve r19-r28
+ * r29 and r30 are used as the frame register and link register (avoid)
+ * See the ARM Procedure Call Reference for details.
+ */
+struct target_pt_regs {
+    uint64_t    regs[31];
+    uint64_t    sp;
+    uint64_t    pc;
+    uint64_t    pstate;
+};
+
+#define TARGET_HW_MACHINE       "arm64"
+#define TARGET_HW_MACHINE_ARCH  "aarch64"
+
+#endif /* BSD_USER_AARCH64_TARGET_SYSCALL_H */
-- 
2.34.1