From fccdf292df18cb136a9c7081a790ad436010c989 Mon Sep 17 00:00:00 2001
From: Zihao Yu <yuzihao@ict.ac.cn>
Date: Mon, 10 Feb 2020 15:10:44 +0800
Subject: [PATCH] *-nemu,cte: support _kcontext() with arg

---
 am/src/mips32/nemu/cte.c  | 1 +
 am/src/riscv32/nemu/cte.c | 1 +
 am/src/x86/nemu/cte.c     | 6 +++++-
 am/src/x86/nemu/trap.S    | 5 +++++
 4 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/am/src/mips32/nemu/cte.c b/am/src/mips32/nemu/cte.c
index 31e24419..ae433380 100644
--- a/am/src/mips32/nemu/cte.c
+++ b/am/src/mips32/nemu/cte.c
@@ -61,6 +61,7 @@ int _cte_init(_Context*(*handler)(_Event, _Context*)) {
 _Context *_kcontext(_Area kstack, void (*entry)(void *), void *arg) {
   _Context *c = (_Context*)kstack.end - 1;
   c->epc = (uintptr_t)entry;
+  c->GPR2 = (uintptr_t)arg; // a0
   return c;
 }
 
diff --git a/am/src/riscv32/nemu/cte.c b/am/src/riscv32/nemu/cte.c
index 6eaa18bd..0a04e515 100644
--- a/am/src/riscv32/nemu/cte.c
+++ b/am/src/riscv32/nemu/cte.c
@@ -49,6 +49,7 @@ _Context *_kcontext(_Area kstack, void (*entry)(void *), void *arg) {
   _Context *c = (_Context*)kstack.end - 1;
 
   c->epc = (uintptr_t)entry;
+  c->GPR2 = (uintptr_t)arg;
   c->status = 0x000c0100;
   return c;
 }
diff --git a/am/src/x86/nemu/cte.c b/am/src/x86/nemu/cte.c
index 1ae228c5..62a46491 100644
--- a/am/src/x86/nemu/cte.c
+++ b/am/src/x86/nemu/cte.c
@@ -63,11 +63,15 @@ int _cte_init(_Context*(*handler)(_Event, _Context*)) {
   return 0;
 }
 
+void __am_kcontext_start();
+
 _Context* _kcontext(_Area kstack, void (*entry)(void *), void *arg) {
   _Context *c = (_Context *)kstack.end - 1;
   c->cs = 0x8;
-  c->eip = (uintptr_t)entry;
+  c->eip = (uintptr_t)__am_kcontext_start;
   c->eflags = 0x2 | FL_IF;
+  c->GPR1 = (uintptr_t)arg;
+  c->GPR2 = (uintptr_t)entry;
   return c;
 }
 
diff --git a/am/src/x86/nemu/trap.S b/am/src/x86/nemu/trap.S
index e5197d15..207dfbc7 100644
--- a/am/src/x86/nemu/trap.S
+++ b/am/src/x86/nemu/trap.S
@@ -4,6 +4,11 @@
 .globl __am_irq0;        __am_irq0:  pushl $0;  pushl   $32; jmp __am_asm_trap
 .globl __am_vecnull;  __am_vecnull:  pushl $0;  pushl   $-1; jmp __am_asm_trap
 
+.globl __am_kcontext_start
+__am_kcontext_start:
+  pushl %eax
+  call *%ebx
+
 __am_asm_trap:
   pushal