1 files changed, 98 insertions, 0 deletions

diff --git a/src/kernel/trap/trampoline.S b/src/kernel/trap/trampoline.S
new file mode 100644
index 0000000..478d345
--- /dev/null
+++ b/src/kernel/trap/trampoline.S
@@ -0,0 +1,98 @@
+.section .text
+.globl trampoline
+.globl uservec
+.globl userret
+
+.align 12
+trampoline:
+.align 4
+uservec:    
+    
+    csrrw a0, sscratch, a0
+
+    sd ra, 40(a0)
+    sd sp, 48(a0)
+    sd gp, 56(a0)
+    sd tp, 64(a0)
+    sd t0, 72(a0)
+    sd t1, 80(a0)
+    sd t2, 88(a0)
+    sd s0, 96(a0)
+    sd s1, 104(a0)
+    sd a1, 120(a0)
+    sd a2, 128(a0)
+    sd a3, 136(a0)
+    sd a4, 144(a0)
+    sd a5, 152(a0)
+    sd a6, 160(a0)
+    sd a7, 168(a0)
+    sd s2, 176(a0)
+    sd s3, 184(a0)
+    sd s4, 192(a0)
+    sd s5, 200(a0)
+    sd s6, 208(a0)
+    sd s7, 216(a0)
+    sd s8, 224(a0)
+    sd s9, 232(a0)
+    sd s10, 240(a0)
+    sd s11, 248(a0)
+    sd t3, 256(a0)
+    sd t4, 264(a0)
+    sd t5, 272(a0)
+    sd t6, 280(a0)
+
+    csrr t0, sscratch
+    sd t0, 112(a0)
+
+    ld sp, 8(a0)
+    ld tp, 32(a0)
+    ld t0, 16(a0)
+    ld t1, 0(a0)
+
+    csrw satp, t1
+    sfence.vma zero, zero
+
+    jr t0
+
+.align 4
+userret:
+    
+    csrw satp, a1
+    sfence.vma zero, zero
+
+    csrw sscratch, a0
+
+    ld ra, 40(a0)
+    ld sp, 48(a0)
+    ld gp, 56(a0)
+    ld tp, 64(a0)
+    ld t0, 72(a0)
+    ld t1, 80(a0)
+    ld t2, 88(a0)
+    ld s0, 96(a0)
+    ld s1, 104(a0)
+    ld a1, 120(a0)
+    ld a2, 128(a0)
+    ld a3, 136(a0)
+    ld a4, 144(a0)
+    ld a5, 152(a0)
+    ld a6, 160(a0)
+    ld a7, 168(a0)
+    ld s2, 176(a0)
+    ld s3, 184(a0)
+    ld s4, 192(a0)
+    ld s5, 200(a0)
+    ld s6, 208(a0)
+    ld s7, 216(a0)
+    ld s8, 224(a0)
+    ld s9, 232(a0)
+    ld s10, 240(a0)
+    ld s11, 248(a0)
+    ld t3, 256(a0)
+    ld t4, 264(a0)
+    ld t5, 272(a0)
+    ld t6, 280(a0)
+    
+    ld a0, 112(a0)
+    
+    sret
\ No newline at end of file