qemu-e2k/bsd-user/arm/target_arch_thread.h
Warner Losh f1f22450e2 bsd-user/arm/target_arch_thread.h: Assume a FreeBSD target
Since we can't run on anything else, assume for the moment that this is
a FreeBSD target. In the future, we'll need to handle this properly
via some include file in bsd-user/*bsd/arm/mumble.h. There's a number
of other diffs that would be needed to make things work on OtherBSD,
so it doesn't make sense to preseve this one detail today.

Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Kyle Evans <kevans@FreeBSD.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2022-02-26 10:01:38 -07:00

81 lines
2.9 KiB
C

/*
* arm thread support
*
* Copyright (c) 2013 Stacey D. Son
*
* 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_THREAD_H_
#define _TARGET_ARCH_THREAD_H_
/* Compare to arm/arm/vm_machdep.c cpu_set_upcall_kse() */
static inline void target_thread_set_upcall(CPUARMState *env, abi_ulong entry,
abi_ulong arg, abi_ulong stack_base, abi_ulong stack_size)
{
abi_ulong sp;
/*
* Make sure the stack is properly aligned.
* arm/include/param.h (STACKLIGN() macro)
*/
sp = (u_int)(stack_base + stack_size) & ~0x7;
/* sp = stack base */
env->regs[13] = sp;
/* pc = start function entry */
env->regs[15] = entry & 0xfffffffe;
/* r0 = arg */
env->regs[0] = arg;
env->spsr = ARM_CPU_MODE_USR;
/*
* Thumb mode is encoded by the low bit in the entry point (since ARM can't
* execute at odd addresses). When it's set, set the Thumb bit (T) in the
* CPSR.
*/
cpsr_write(env, (entry & 1) * CPSR_T, CPSR_T, CPSRWriteByInstr);
}
static inline void target_thread_init(struct target_pt_regs *regs,
struct image_info *infop)
{
abi_long stack = infop->start_stack;
memset(regs, 0, sizeof(*regs));
regs->ARM_cpsr = ARM_CPU_MODE_USR;
/*
* Thumb mode is encoded by the low bit in the entry point (since ARM can't
* execute at odd addresses). When it's set, set the Thumb bit (T) in the
* CPSR.
*/
if (infop->entry & 1) {
regs->ARM_cpsr |= CPSR_T;
}
regs->ARM_pc = infop->entry & 0xfffffffe;
regs->ARM_sp = stack;
regs->ARM_lr = infop->entry & 0xfffffffe;
/*
* FreeBSD kernel passes the ps_strings pointer in r0. This is used by some
* programs to set status messages that we see in ps. bsd-user doesn't
* support that functionality, so it's ignored. When set to 0, FreeBSD's csu
* code ignores it. For the static case, r1 and r2 are effectively ignored
* by the csu __startup() routine. For the dynamic case, rtld saves r0 but
* generates r1 and r2 and passes them into the csu _startup.
*
* r0 ps_strings 0 passed since ps arg setting not supported
* r1 obj_main ignored by _start(), so 0 passed
* r2 cleanup generated by rtld or ignored by _start(), so 0 passed
*/
}
#endif /* !_TARGET_ARCH_THREAD_H_ */