aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorWarner Losh <imp@bsdimp.com>2021-09-23 09:16:15 -0600
committerWarner Losh <imp@bsdimp.com>2022-01-07 22:58:51 -0700
commitf10521cc22aec74ad259bee03ca15ae5ee561c6c (patch)
treea6a2ac85d2f61bf42e046e3dea46223a9c316650
parenteacb50b8d92452251d890f6bfb4ac8eb22acb8d2 (diff)
bsd-user/arm/target_arch_thread.h: Routines to create and switch to a thread
Implement target_thread_init (to create a thread) and target_set_upcall (to switch to a thread) for arm. Signed-off-by: Stacey Son <sson@FreeBSD.org> Signed-off-by: Kyle Evans <kevans@FreeBSD.org> Signed-off-by: Warner Losh <imp@bsdimp.com> Reviewed-by: Kyle Evans <kevans@FreeBSD.org>
-rw-r--r--bsd-user/arm/target_arch_thread.h82
1 files changed, 82 insertions, 0 deletions
diff --git a/bsd-user/arm/target_arch_thread.h b/bsd-user/arm/target_arch_thread.h
new file mode 100644
index 0000000000..11c7f76583
--- /dev/null
+++ b/bsd-user/arm/target_arch_thread.h
@@ -0,0 +1,82 @@
+/*
+ * 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;
+ if (bsd_type == target_freebsd) {
+ 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_ */