diff --git a/kernel/src/arch/riscv32/boot/trap.asm b/kernel/src/arch/riscv32/boot/trap.asm
index 0f3bc3d..04d206d 100644
--- a/kernel/src/arch/riscv32/boot/trap.asm
+++ b/kernel/src/arch/riscv32/boot/trap.asm
@@ -17,39 +17,39 @@ _restore_kernel_sp:
     # sscratch = previous-sp, sp = kernel-sp
 _save_context:
     # provide room for trap frame
-    addi sp, sp, -36 * 4
+    addi sp, sp, -36 * XLENB
     # save x registers except x2 (sp)
-    sw x1, 1*4(sp)
-    sw x3, 3*4(sp)
+    sw x1, 1*XLENB(sp)
+    sw x3, 3*XLENB(sp)
     # tp(x4) = hartid. DON'T change.
-    # sw x4, 4*4(sp)
-    sw x5, 5*4(sp)
-    sw x6, 6*4(sp)
-    sw x7, 7*4(sp)
-    sw x8, 8*4(sp)
-    sw x9, 9*4(sp)
-    sw x10, 10*4(sp)
-    sw x11, 11*4(sp)
-    sw x12, 12*4(sp)
-    sw x13, 13*4(sp)
-    sw x14, 14*4(sp)
-    sw x15, 15*4(sp)
-    sw x16, 16*4(sp)
-    sw x17, 17*4(sp)
-    sw x18, 18*4(sp)
-    sw x19, 19*4(sp)
-    sw x20, 20*4(sp)
-    sw x21, 21*4(sp)
-    sw x22, 22*4(sp)
-    sw x23, 23*4(sp)
-    sw x24, 24*4(sp)
-    sw x25, 25*4(sp)
-    sw x26, 26*4(sp)
-    sw x27, 27*4(sp)
-    sw x28, 28*4(sp)
-    sw x29, 29*4(sp)
-    sw x30, 30*4(sp)
-    sw x31, 31*4(sp)
+    # sw x4, 4*XLENB(sp)
+    sw x5, 5*XLENB(sp)
+    sw x6, 6*XLENB(sp)
+    sw x7, 7*XLENB(sp)
+    sw x8, 8*XLENB(sp)
+    sw x9, 9*XLENB(sp)
+    sw x10, 10*XLENB(sp)
+    sw x11, 11*XLENB(sp)
+    sw x12, 12*XLENB(sp)
+    sw x13, 13*XLENB(sp)
+    sw x14, 14*XLENB(sp)
+    sw x15, 15*XLENB(sp)
+    sw x16, 16*XLENB(sp)
+    sw x17, 17*XLENB(sp)
+    sw x18, 18*XLENB(sp)
+    sw x19, 19*XLENB(sp)
+    sw x20, 20*XLENB(sp)
+    sw x21, 21*XLENB(sp)
+    sw x22, 22*XLENB(sp)
+    sw x23, 23*XLENB(sp)
+    sw x24, 24*XLENB(sp)
+    sw x25, 25*XLENB(sp)
+    sw x26, 26*XLENB(sp)
+    sw x27, 27*XLENB(sp)
+    sw x28, 28*XLENB(sp)
+    sw x29, 29*XLENB(sp)
+    sw x30, 30*XLENB(sp)
+    sw x31, 31*XLENB(sp)
 
     # get sp, sstatus, sepc, stval, scause
     # set sscratch = 0
@@ -59,20 +59,20 @@ _save_context:
     csrr s3, (xtval)
     csrr s4, (xcause)
     # store sp, sstatus, sepc, sbadvaddr, scause
-    sw s0, 2*4(sp)
-    sw s1, 32*4(sp)
-    sw s2, 33*4(sp)
-    sw s3, 34*4(sp)
-    sw s4, 35*4(sp)
+    sw s0, 2*XLENB(sp)
+    sw s1, 32*XLENB(sp)
+    sw s2, 33*XLENB(sp)
+    sw s3, 34*XLENB(sp)
+    sw s4, 35*XLENB(sp)
 .endm
 
 .macro RESTORE_ALL
-    lw s1, 32*4(sp)             # s1 = sstatus
-    lw s2, 33*4(sp)             # s2 = sepc
+    lw s1, 32*XLENB(sp)             # s1 = sstatus
+    lw s2, 33*XLENB(sp)             # s2 = sepc
     andi s0, s1, 1 << 8
     bnez s0, _restore_context   # back to S-mode? (sstatus.SPP = 1)
 _save_kernel_sp:
-    addi s0, sp, 36*4
+    addi s0, sp, 36*XLENB
     csrw (xscratch), s0         # sscratch = kernel-sp
 _restore_context:
     # restore sstatus, sepc
@@ -80,38 +80,38 @@ _restore_context:
     csrw (xepc), s2
 
     # restore x registers except x2 (sp)
-    lw x1, 1*4(sp)
-    lw x3, 3*4(sp)
-    # lw x4, 4*4(sp)
-    lw x5, 5*4(sp)
-    lw x6, 6*4(sp)
-    lw x7, 7*4(sp)
-    lw x8, 8*4(sp)
-    lw x9, 9*4(sp)
-    lw x10, 10*4(sp)
-    lw x11, 11*4(sp)
-    lw x12, 12*4(sp)
-    lw x13, 13*4(sp)
-    lw x14, 14*4(sp)
-    lw x15, 15*4(sp)
-    lw x16, 16*4(sp)
-    lw x17, 17*4(sp)
-    lw x18, 18*4(sp)
-    lw x19, 19*4(sp)
-    lw x20, 20*4(sp)
-    lw x21, 21*4(sp)
-    lw x22, 22*4(sp)
-    lw x23, 23*4(sp)
-    lw x24, 24*4(sp)
-    lw x25, 25*4(sp)
-    lw x26, 26*4(sp)
-    lw x27, 27*4(sp)
-    lw x28, 28*4(sp)
-    lw x29, 29*4(sp)
-    lw x30, 30*4(sp)
-    lw x31, 31*4(sp)
+    lw x1, 1*XLENB(sp)
+    lw x3, 3*XLENB(sp)
+    # lw x4, 4*XLENB(sp)
+    lw x5, 5*XLENB(sp)
+    lw x6, 6*XLENB(sp)
+    lw x7, 7*XLENB(sp)
+    lw x8, 8*XLENB(sp)
+    lw x9, 9*XLENB(sp)
+    lw x10, 10*XLENB(sp)
+    lw x11, 11*XLENB(sp)
+    lw x12, 12*XLENB(sp)
+    lw x13, 13*XLENB(sp)
+    lw x14, 14*XLENB(sp)
+    lw x15, 15*XLENB(sp)
+    lw x16, 16*XLENB(sp)
+    lw x17, 17*XLENB(sp)
+    lw x18, 18*XLENB(sp)
+    lw x19, 19*XLENB(sp)
+    lw x20, 20*XLENB(sp)
+    lw x21, 21*XLENB(sp)
+    lw x22, 22*XLENB(sp)
+    lw x23, 23*XLENB(sp)
+    lw x24, 24*XLENB(sp)
+    lw x25, 25*XLENB(sp)
+    lw x26, 26*XLENB(sp)
+    lw x27, 27*XLENB(sp)
+    lw x28, 28*XLENB(sp)
+    lw x29, 29*XLENB(sp)
+    lw x30, 30*XLENB(sp)
+    lw x31, 31*XLENB(sp)
     # restore sp last
-    lw x2, 2*4(sp)
+    lw x2, 2*XLENB(sp)
 .endm
 
     .section .text
diff --git a/kernel/src/arch/riscv32/compiler_rt.c b/kernel/src/arch/riscv32/compiler_rt.c
index 8746716..930c564 100644
--- a/kernel/src/arch/riscv32/compiler_rt.c
+++ b/kernel/src/arch/riscv32/compiler_rt.c
@@ -49,6 +49,7 @@ int __atomic_fetch_sub_4(int* ptr, int val) {
     return res;
 }
 
+#ifdef TARGET_IS_64BITS
 typedef unsigned long long u64;
 
 u64 __atomic_load_8(u64 *src) {
@@ -87,3 +88,4 @@ u64 __atomic_fetch_sub_8(u64* ptr, u64 val) {
     __asm__ __volatile__("amoadd.d.rl %0, %1, (%2)" : "=r"(res) : "r"(-val), "r"(ptr) : "memory");
     return res;
 }
+#endif
diff --git a/kernel/src/arch/riscv32/mod.rs b/kernel/src/arch/riscv32/mod.rs
index 72dae42..32b7dd8 100644
--- a/kernel/src/arch/riscv32/mod.rs
+++ b/kernel/src/arch/riscv32/mod.rs
@@ -63,6 +63,18 @@ global_asm!("
     .macro XRET\n sret\n .endm
 ");
 
+#[cfg(target_pointer_width = "32")]
+global_asm!("
+    .equ XLENB,     4
+    .equ XLENb,     32
+");
+#[cfg(target_pointer_width = "64")]
+global_asm!("
+    .equ XLENB,     8
+    .equ XLENb,     64
+");
+
+
 #[cfg(feature = "board_k210")]
 global_asm!(include_str!("boot/boot_k210.asm"));
 global_asm!(include_str!("boot/entry.asm"));
@@ -84,4 +96,4 @@ static mut BBL_FUNCTIONS_PTR: *const BBLFunctions = ::core::ptr::null();
 use lazy_static::lazy_static;
 lazy_static! {
     static ref BBL: BBLFunctions = unsafe { BBL_FUNCTIONS_PTR.read() };
-}
\ No newline at end of file
+}