diff --git "a/10225101447 \345\224\220\347\241\225 \345\256\236\351\252\214\344\270\200\345\256\236\351\252\214\346\212\245\345\221\212.docx" "b/10225101447 \345\224\220\347\241\225 \345\256\236\351\252\214\344\270\200\345\256\236\351\252\214\346\212\245\345\221\212.docx"
new file mode 100755
index 0000000000000000000000000000000000000000..c0657c76f6d3974bca4a6e956389e62edb43a29e
Binary files /dev/null and "b/10225101447 \345\224\220\347\241\225 \345\256\236\351\252\214\344\270\200\345\256\236\351\252\214\346\212\245\345\221\212.docx" differ
diff --git a/kernel/arch/aarch64/boot/raspi3/init/tools.S b/kernel/arch/aarch64/boot/raspi3/init/tools.S
index 805e03e8ae20ee17833cd42ce418ed352efb3176..7aa97208d05e8674eb5cd59c0cb872b5661d9ead 100644
--- a/kernel/arch/aarch64/boot/raspi3/init/tools.S
+++ b/kernel/arch/aarch64/boot/raspi3/init/tools.S
@@ -57,7 +57,7 @@
 
 BEGIN_FUNC(arm64_elX_to_el1)
 	/* LAB 1 TODO 1 BEGIN */
-
+	mrs x9, CurrentEL
 	/* LAB 1 TODO 1 END */
 
 	// Check the current exception level.
@@ -75,7 +75,12 @@ BEGIN_FUNC(arm64_elX_to_el1)
 
 	// Set the return address and exception level.
 	/* LAB 1 TODO 2 BEGIN */
-
+	
+	//msr sp_el1,
+	adr x9, .Ltarget
+    msr 	elr_el3,x9
+	mov x9,#(0b1111<<6|0b0101)
+	msr     spsr_el3,x9
 	/* LAB 1 TODO 2 END */
 
 .Lin_el2:
@@ -249,7 +254,10 @@ BEGIN_FUNC(el1_mmu_activate)
 	mrs     x8, sctlr_el1
 	/* Enable MMU */
 	/* LAB 1 TODO 4 BEGIN */
-
+	ORR X8, X8, #(0b11111)//MMU enable
+	ORR X8, X8, #(0b1<<12)//cache
+	//ORR X8, X8, #1
+	MSR SCTLR_EL1, X8 
 	/* LAB 1 TODO 4 END */
 	/* Disable alignment checking */
 	bic     x8, x8, #SCTLR_EL1_A
diff --git a/kernel/arch/aarch64/boot/raspi3/peripherals/uart.c b/kernel/arch/aarch64/boot/raspi3/peripherals/uart.c
index 3a9ec299f2f801cfa382c3540b3090ba4c1b3512..fab999e751ea048cfe0fa53ae21f297c17c539d6 100644
--- a/kernel/arch/aarch64/boot/raspi3/peripherals/uart.c
+++ b/kernel/arch/aarch64/boot/raspi3/peripherals/uart.c
@@ -77,6 +77,10 @@ static void early_uart_send(unsigned int c)
 void uart_send_string(char *str)
 {
         /* LAB 1 TODO 3 BEGIN */
-
+        int i=0;
+        while(str[i]!='\0'){
+                early_uart_send(str[i]);
+                i++;
+        }
         /* LAB 1 TODO 3 END */
 }