diff --git a/.cargo/config.toml b/.cargo/config.toml
index a249dee7760fa57e76ea6ae3481949363b460d81..1f583ac657521bf7c98c1500a0ca30b20878413f 100644
--- a/.cargo/config.toml
+++ b/.cargo/config.toml
@@ -8,7 +8,8 @@
 # runner = "arm-none-eabi-gdb -q -x openocd.gdb"
 # runner = "gdb-multiarch -q -x openocd.gdb"
 # runner = "gdb -q -x openocd.gdb"
-  runner = "qemu-system-gnuarmeclipse --verbose --verbose --board STM32F4-Discovery --mcu STM32F407VG -d unimp,guest_errors    --nographic --semihosting-config enable=on,target=native --image "
+  # runner = "qemu-system-gnuarmeclipse --verbose --verbose --board STM32F4-Discovery --mcu STM32F407VG -d unimp,guest_errors    --nographic --semihosting-config enable=on,target=native --image "
+runner = "qemu-system-arm -M raspi2 -serial stdio -chardev socket,id=monitor,path=monitor.sock,server,nowait -monitor chardev:monitor  -D ./qemu.log  -d in_asm -d cpu_reset -d in_asm,int,mmu   -kernel "
 
 rustflags = [
   # This is needed if your flash or ram addresses are not aligned to 0x10000 in memory.x
@@ -16,7 +17,8 @@ rustflags = [
   #"-C", "link-arg=--nmagic",
 
   # LLD (shipped with the Rust toolchain) is used as the default linker
-  "-C", "link-arg=-Tboards/stm32f4xx/link.x",
+  # "-C", "link-arg=-Tboards/stm32f4xx/link.x",
+  "-C", "link-arg=-Tboards/raspberrypi/link.x",
 
   # if you run into problems with LLD switch to the GNU linker by commenting out
   # this line
@@ -34,8 +36,9 @@ rustflags = [
 # Pick ONE of these compilation targets
 # target = "thumbv6m-none-eabi"        # Cortex-M0 and Cortex-M0+
 #target = "thumbv7m-none-eabi"        # Cortex-M3
-target = "thumbv7em-none-eabi"       # Cortex-M4 and Cortex-M7 (no FPU)
+# target = "thumbv7em-none-eabi"       # Cortex-M4 and Cortex-M7 (no FPU)
 # target = "thumbv7em-none-eabihf"     # Cortex-M4F and Cortex-M7F (with FPU)
 # target = "thumbv8m.base-none-eabi"   # Cortex-M23
 # target = "thumbv8m.main-none-eabi"   # Cortex-M33 (no FPU)
 # target = "thumbv8m.main-none-eabihf" # Cortex-M33 (with FPU)
+target = "armv7a-none-eabi"
diff --git a/Cargo.lock b/Cargo.lock
index 0e915a71a65ee4586825e705cfb64923544329fd..483ee6da345eb4aba099e9dbcd7f3145d9e4c09c 100755
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -52,6 +52,10 @@ checksum = "46afbd2983a5d5a7bd740ccb198caf5b82f45c40c09c0eed36052d91cb92e719"
 name = "cmsis"
 version = "0.1.0"
 
+[[package]]
+name = "cortex-a7"
+version = "0.1.0"
+
 [[package]]
 name = "cortex-m"
 version = "0.6.7"
@@ -220,6 +224,15 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e2a38df5b15c8d5c7e8654189744d8e396bddc18ad48041a500ce52d6948941f"
 
+[[package]]
+name = "raspberrypi"
+version = "0.1.0"
+dependencies = [
+ "kernel",
+ "panic-halt",
+ "utils",
+]
+
 [[package]]
 name = "riscv"
 version = "0.1.0"
diff --git a/Cargo.toml b/Cargo.toml
index 2e49d115c6ed627a59406458065b53e70c323421..55a52e1db2cf33c0ecd449a293f5f52cbce6832e 100755
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,11 +4,14 @@ members = [
     "kal/posix",
     "kernel/source",
     "kernel/arch/arm/cortex-m4",
+    "kernel/arch/arm/cortex-a7",
     "kernel/arch/riscv",
     "boards/stm32f4xx",
+    "boards/raspberrypi",
     "components/exchook",
     "utils",
 ]
+
 exclude = [
 
 ]
@@ -19,6 +22,7 @@ lto = false
 opt-level = "z"
 debug = true
 
+
 [profile.release]
 panic = "abort"
 lto = true
diff --git a/README.md b/README.md
index f36b86fea863b2a6b8484761211dc1d7093210e5..d092095756a104d91582363001993eaca38ea5f2 100755
--- a/README.md
+++ b/README.md
@@ -22,7 +22,7 @@ rust stable安装
 rust nightly安装(使用嵌入式汇编时，需切换到nightly版本)
 1.  rustup install nightly
 2.  rustup default nightly
-3.  rustup target add thumbv7em-none-eabi
+3.  rustup target add thumbv7em-none-eabi armv7a-none-eabi
 
 #### 使用说明
 
diff --git a/boards/raspberrypi/Cargo.toml b/boards/raspberrypi/Cargo.toml
new file mode 100755
index 0000000000000000000000000000000000000000..43440b01ce808f1ebe4ce961a57f0fe4991d2d5b
--- /dev/null
+++ b/boards/raspberrypi/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+edition = "2018"
+readme = "README.md"
+name = "raspberrypi"
+version = "0.1.0"
+authors = ["evilbinary <rootntsd@gmail.com>"]
+
+[dependencies]
+panic-halt = "0.2.0"
+# utils = {path = "../../utils/"}
+# kernel = {path = "../../kernel/source"}
+
diff --git a/boards/raspberrypi/link.x b/boards/raspberrypi/link.x
new file mode 100644
index 0000000000000000000000000000000000000000..abc9ed25695f2505b79302c9bed0cb7eb255f57b
--- /dev/null
+++ b/boards/raspberrypi/link.x
@@ -0,0 +1,37 @@
+ENTRY(_start)
+K_VIR_ADDR = 0x00000;
+K_PHY_ADDR = 0x00000;
+PAGE_SIZE    = 0x100;
+SECTIONS
+{
+        /* Code. */
+        .text K_VIR_ADDR : AT(K_PHY_ADDR)
+        {
+		. = ALIGN(PAGE_SIZE);
+                *(.text._start)
+        }
+        
+        /* Read-only data. */
+        .rodata  : ALIGN(4K)
+        {
+                *(.rodata)
+        }
+
+        /* Read-write data (initialized) */
+        .data  : ALIGN(4K)
+        {
+                *(.data )
+                _stack_top = . ; 
+        }
+        
+        /* Read-write data (uninitialized) and stack */
+        .bss  : ALIGN(4K)
+        {
+                *(COMMON)
+                *(.bss)
+        }
+        .ARM.exidx :{
+                *(.ARM)
+        }
+       _end = .;
+}
diff --git a/boards/raspberrypi/src/main.rs b/boards/raspberrypi/src/main.rs
new file mode 100644
index 0000000000000000000000000000000000000000..17c2251d6d4f903697dc33c1761ad90f5cabea38
--- /dev/null
+++ b/boards/raspberrypi/src/main.rs
@@ -0,0 +1,112 @@
+#![no_main]
+#![no_std]
+#![feature(asm)]
+use panic_halt as _;
+
+
+extern "C" {
+	static mut _stack_top: u32;
+}
+
+
+fn io_write(reg: u32, val: u32) {
+    unsafe { *(reg as *mut u32)= val; }
+}
+
+fn io_read(reg: u32) -> u32 {
+    unsafe { *(reg as *const u32) }
+}
+
+pub fn uart_init(){
+    unsafe {
+        const BASE:u32=0x3F000000;
+        // turn off
+        *((BASE+0x00201030) as *mut u32) |= 0 as u32;
+
+        //clear int
+        *((BASE+0x00201044) as *mut u32) = 0x7FF as u32;
+        //115200
+        *((BASE+0x00201024) as *mut u32) = 0x7FF as u32;
+
+        //fbrd
+        *((BASE+0x00201028) as *mut u32) = 0xB as u32;
+        //8n1
+        *((BASE+0x0020102C) as *mut u32) = 0b11 << 5 as u32;
+
+        //enable tx rx
+        *((BASE+0x00201030) as *mut u32) = 0x301 as u32;
+    }
+}
+
+
+pub fn uart_send(byte: u8) {
+    unsafe {
+        const BASE:u32 = 0x3F000000;
+        while (*((BASE+0x00201018) as *mut u32) & 0x20!=0) {
+        }
+        *((BASE +0x00201000) as *mut u32)= byte as u32;
+    }
+}
+
+fn write_string(msg: &str) {
+    for c in msg.chars() {
+        uart_send(c as u8)
+    }
+}
+
+
+#[no_mangle]
+pub unsafe fn _start() {
+    asm!("
+    mrc p15, #0, r1, c0, c0, #5
+    and r1, r1, #3
+    cmp r1, #0
+    bne halt 
+
+    mrs r0, cpsr
+    ldr sp, = _stack_top
+    ldr fp, = _stack_top
+    
+    // set sp in abt mode.
+    bic r1, r0, #0x1F
+    orr r1, r1, #0x17
+    msr cpsr_c,r1
+    mov sp, #0x1000
+    
+    // set sp in undf mode.
+    bic r1, r0, #0x1F
+    orr r1, r1, #0x1B
+    msr cpsr_c,r1
+    mov sp, #0x1000
+    
+    // set sp in irq mode.
+    bic r1, r0, #0x1F
+    orr r1, r1, #0x12
+    msr cpsr_c,r1
+    mov sp, #0x2000
+    //ldr sp,= stack_irq
+    
+    // set sp in svc mode.
+    bic r1, r0, #0x1F
+    orr r1, r1, #0x13
+    msr cpsr_c, r0
+    mov sp, #0x3000
+    //ldr sp,= stack_svc
+    bl main
+
+    halt:
+    wfe
+    b halt
+    "
+);
+    main();
+}
+
+#[no_mangle]
+fn main() {
+    uart_init();
+    write_string("Hello,liteos cortex-a7!\n");
+
+    loop{
+    }
+}
diff --git a/boards/stm32f4xx/Cargo.toml b/boards/stm32f4xx/Cargo.toml
index 68c6374daef51ecd00b5dbce744a5bb49392c0ce..76b689a5afd29dd4cc2b72b9cb269408f6d0a6b7 100755
--- a/boards/stm32f4xx/Cargo.toml
+++ b/boards/stm32f4xx/Cargo.toml
@@ -4,6 +4,7 @@ edition = "2018"
 readme = "README.md"
 name = "stm32f4xx"
 version = "0.1.0"
+default-run ="stm32f4xx"
 
 [dependencies]
 cortex-m = "0.6.0"
diff --git a/kernel/arch/arm/cortex-a7/Cargo.toml b/kernel/arch/arm/cortex-a7/Cargo.toml
new file mode 100644
index 0000000000000000000000000000000000000000..45f22cec913fabad16c675fb950e304349df504b
--- /dev/null
+++ b/kernel/arch/arm/cortex-a7/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "cortex-a7"
+version = "0.1.0"
+edition = "2018"
+authors = ["evilbinary <rootntsd@gmail.com>"]
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/kernel/arch/arm/cortex-a7/src/lib.rs b/kernel/arch/arm/cortex-a7/src/lib.rs
new file mode 100644
index 0000000000000000000000000000000000000000..2e67b25f743b271db154fe7e6bf09153ad0363f4
--- /dev/null
+++ b/kernel/arch/arm/cortex-a7/src/lib.rs
@@ -0,0 +1,8 @@
+#![no_std]
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn it_works() {
+        assert_eq!(2 + 2, 4);
+    }
+}