16 changed files with 225 additions and 231 deletions
--- a/experiments/Cargo.toml
+++ b/experiments/Cargo.toml
@ -18,5 +18,5 @@ embedded-hal = "0.2"
 libregister = { path = "../libregister" }
 libcortex_a9 = { path = "../libcortex_a9" }
 libboard_zynq = { path = "../libboard_zynq" }
-libsupport_zynq = { path = "../libsupport_zynq", default-features = false, features = ["panic_handler", "dummy_fiq_handler"]}
+libsupport_zynq = { path = "../libsupport_zynq", default-features = false, features = ["panic_handler"]}
 libasync = { path = "../libasync" }
--- a/experiments/src/main.rs
+++ b/experiments/src/main.rs
@ -39,7 +39,7 @@ use libcortex_a9::{
 };
 use libregister::{RegisterR, RegisterW};
 use libsupport_zynq::{
-    boot, exception_vectors, ram,
+    boot, ram,
 };
 use log::{info, warn};
 use core::sync::atomic::{AtomicBool, Ordering};
@ -56,29 +56,19 @@ extern "C" {
 static CORE1_RESTART: AtomicBool = AtomicBool::new(false);

 interrupt_handler!(IRQ, irq, __irq_stack0_start, __irq_stack1_start, {
-    let mpcore = mpcore::RegisterBlock::mpcore();
-    let mut gic = gic::InterruptController::gic(mpcore);
-    let id = gic.get_interrupt_id();
-    match MPIDR.read().cpu_id(){
-        0 => {
-            if id.0 == 0 {
-                println!("Interrupting core0...");
-                gic.end_interrupt(id);
-                return;
-            }
-        },
-        1 => {
-            if id.0 == 0 {
-                gic.end_interrupt(id);
-                asm::exit_irq();
-                SP.write(&mut __stack1_start as *mut _ as u32);
-                asm::enable_irq();
-                CORE1_RESTART.store(false, Ordering::Relaxed);
-                notify_spin_lock();
-                main_core1();
-            }
-        },
-        _ => {}
+    if MPIDR.read().cpu_id() == 1{
+        let mpcore = mpcore::RegisterBlock::mpcore();
+        let mut gic = gic::InterruptController::gic(mpcore);
+        let id = gic.get_interrupt_id();
+        if id.0 == 0 {
+            gic.end_interrupt(id);
+            asm::exit_irq();
+            SP.write(&mut __stack1_start as *mut _ as u32);
+            asm::enable_irq();
+            CORE1_RESTART.store(false, Ordering::Relaxed);
+            notify_spin_lock();
+            main_core1();
+        }
    }
    stdio::drop_uart();
    println!("IRQ");
@ -96,7 +86,6 @@ pub fn restart_core1() {

 #[no_mangle]
 pub fn main_core0() {
-    exception_vectors::set_vector_table(0x0);
    // zynq::clocks::CpuClocks::enable_io(1_250_000_000);
    enable_l2_cache(0x8);
    println!("\nZynq experiments");
@ -145,10 +134,6 @@ pub fn main_core0() {
    ddr.memtest();
    ram::init_alloc_ddr(&mut ddr);

-    info!("Send software interrupt to core0");
-    interrupt_controller.send_sgi(gic::InterruptId(0), gic::CPUCore::Core0.into());
-    info!("Core0 returned from interrupt");
-
    boot::Core1::start(false);

    let core1_req = unsafe { &mut CORE1_REQ.0 };
--- a/flake.lock
+++ b/flake.lock
@ -3,11 +3,11 @@
    "mozilla-overlay": {
      "flake": false,
      "locked": {
-        "lastModified": 1695805681,
-        "narHash": "sha256-1ElPLD8eFfnuIk0G52HGGpRtQZ4QPCjChRlEOfkZ5ro=",
+        "lastModified": 1650459918,
+        "narHash": "sha256-sroCK+QJTmoXtcRkwZyKOP9iAYOPID2Bwdxn4GkG16w=",
        "owner": "mozilla",
        "repo": "nixpkgs-mozilla",
-        "rev": "6eabade97bc28d707a8b9d82ad13ef143836736e",
+        "rev": "e1f7540fc0a8b989fb8cf701dc4fd7fc76bcf168",
        "type": "github"
      },
      "original": {
@ -18,16 +18,16 @@
    },
    "nixpkgs": {
      "locked": {
-        "lastModified": 1701389149,
-        "narHash": "sha256-rU1suTIEd5DGCaAXKW6yHoCfR1mnYjOXQFOaH7M23js=",
+        "lastModified": 1653920503,
+        "narHash": "sha256-BBeCZwZImtjP3oYy4WogkQYy5OxNyfNciVSc1AfZgLQ=",
        "owner": "NixOS",
        "repo": "nixpkgs",
-        "rev": "5de0b32be6e85dc1a9404c75131316e4ffbc634c",
+        "rev": "a634c8f6c1fbf9b9730e01764999666f3436f10a",
        "type": "github"
      },
      "original": {
        "owner": "NixOS",
-        "ref": "nixos-23.11",
+        "ref": "nixos-22.05",
        "repo": "nixpkgs",
        "type": "github"
      }
--- a/flake.nix
+++ b/flake.nix
@ -1,12 +1,12 @@
 {
  description = "Bare-metal Rust on Zynq-7000";

-  inputs.nixpkgs.url = github:NixOS/nixpkgs/nixos-23.11;
+  inputs.nixpkgs.url = github:NixOS/nixpkgs/nixos-22.05;
  inputs.mozilla-overlay = { url = github:mozilla/nixpkgs-mozilla; flake = false; };

  outputs = { self, nixpkgs, mozilla-overlay }:
    let
-      pkgs = import nixpkgs { system = "x86_64-linux"; overlays = [ (import mozilla-overlay) crosspkgs-overlay ]; };
+      pkgs = import nixpkgs { system = "x86_64-linux"; overlays = [ (import mozilla-overlay) ]; };
      
      rustManifest = pkgs.fetchurl {
        url = "https://static.rust-lang.org/dist/2021-01-29/channel-rust-nightly.toml";
@ -26,29 +26,148 @@
        cargo = rust;
      });

-      crosspkgs-overlay = (self: super: {
-        pkgsCross = super.pkgsCross // {
-          zynq-baremetal = import super.path {
-            system = "x86_64-linux";
-            crossSystem = {
-              config = "arm-none-eabihf";
-              libc = "newlib";
-              gcc.cpu = "cortex-a9";
-              gcc.fpu = "vfpv3";
-            };
-          };
+      gnu-platform = "arm-none-eabi";
+
+      binutils-pkg = { zlib, extraConfigureFlags ? [] }: pkgs.stdenv.mkDerivation rec {
+        basename = "binutils";
+        version = "2.30";
+        name = "${basename}-${gnu-platform}-${version}";
+        src = pkgs.fetchurl {
+          url = "https://ftp.gnu.org/gnu/binutils/binutils-${version}.tar.bz2";
+          sha256 = "028cklfqaab24glva1ks2aqa1zxa6w6xmc8q34zs1sb7h22dxspg";
        };
-      });
+        configureFlags = [
+          "--enable-deterministic-archives"
+          "--target=${gnu-platform}"
+          "--with-cpu=cortex-a9"
+          "--with-fpu=vfpv3"
+          "--with-float=hard"
+          "--with-mode=thumb"
+        ] ++ extraConfigureFlags;
+        outputs = [ "out" "info" "man" ];
+        depsBuildBuild = [ pkgs.buildPackages.stdenv.cc ];
+        buildInputs = [ zlib ];
+        enableParallelBuilding = true;
+        meta = {
+          description = "Tools for manipulating binaries (linker, assembler, etc.)";
+          longDescription = ''
+            The GNU Binutils are a collection of binary tools.  The main
+            ones are `ld' (the GNU linker) and `as' (the GNU assembler).
+            They also include the BFD (Binary File Descriptor) library,
+            `gprof', `nm', `strip', etc.
+          '';
+          homepage = http://www.gnu.org/software/binutils/;
+          license = pkgs.lib.licenses.gpl3Plus;
+          /* Give binutils a lower priority than gcc-wrapper to prevent a
+            collision due to the ld/as wrappers/symlinks in the latter. */
+          priority = "10";
+        };
+      };
+
+      gcc-pkg = { gmp, mpfr, libmpc, platform-binutils, extraConfigureFlags ? [] }: pkgs.stdenv.mkDerivation rec {
+        basename = "gcc";
+        version = "9.1.0";
+        name = "${basename}-${gnu-platform}-${version}";
+        src = pkgs.fetchurl {
+          url = "https://ftp.gnu.org/gnu/gcc/gcc-${version}/gcc-${version}.tar.xz";
+          sha256 = "1817nc2bqdc251k0lpc51cimna7v68xjrnvqzvc50q3ax4s6i9kr";
+        };
+        preConfigure = ''
+          mkdir build
+          cd build
+        '';
+        configureScript = "../configure";
+        configureFlags = [ 
+          "--target=${gnu-platform}"
+          "--with-arch=armv7-a"
+          "--with-tune=cortex-a9"
+          "--with-fpu=vfpv3"
+          "--with-float=hard"
+          "--disable-libssp"
+          "--enable-languages=c"
+          "--with-as=${platform-binutils}/bin/${gnu-platform}-as"
+          "--with-ld=${platform-binutils}/bin/${gnu-platform}-ld" ] ++ extraConfigureFlags;
+        outputs = [ "out" "info" "man" ];
+        hardeningDisable = [ "format" "pie" ];
+        propagatedBuildInputs = [ gmp mpfr libmpc platform-binutils ];
+        enableParallelBuilding = true;
+        dontFixup = true;
+      };
+
+      newlib-pkg = { platform-binutils, platform-gcc }: pkgs.stdenv.mkDerivation rec {
+        pname = "newlib";
+        version = "3.1.0";
+        src = pkgs.fetchurl {
+          url = "ftp://sourceware.org/pub/newlib/newlib-${version}.tar.gz";
+          sha256 = "0ahh3n079zjp7d9wynggwrnrs27440aac04340chf1p9476a2kzv";
+        };
+        nativeBuildInputs = [ platform-binutils platform-gcc ];
+        configureFlags = [
+          "--target=${gnu-platform}"
+
+          "--with-cpu=cortex-a9"
+          "--with-fpu=vfpv3"
+          "--with-float=hard"
+          "--with-mode=thumb"
+          "--enable-interwork"
+          "--disable-multilib"
+
+          "--disable-newlib-supplied-syscalls"
+          "--with-gnu-ld"
+          "--with-gnu-as"
+          "--disable-newlib-io-float"
+          "--disable-werror"
+        ];
+        dontFixup = true;
+      };
+      gnutoolchain = rec {
+        binutils-bootstrap = pkgs.callPackage binutils-pkg { };
+        gcc-bootstrap = pkgs.callPackage gcc-pkg {
+          platform-binutils = binutils-bootstrap;
+          extraConfigureFlags = [ "--disable-libgcc" ];
+        };
+        newlib = pkgs.callPackage newlib-pkg {
+          platform-binutils = binutils-bootstrap;
+          platform-gcc = gcc-bootstrap;
+        };
+        binutils = pkgs.callPackage binutils-pkg {
+          extraConfigureFlags = [ "--with-lib-path=${newlib}/arm-none-eabi/lib" ];
+        };
+        gcc = pkgs.callPackage gcc-pkg {
+          platform-binutils = binutils;
+          extraConfigureFlags = [ "--enable-newlib" "--with-headers=${newlib}/arm-none-eabi/include" ];
+        };
+      };
+
+      cargo-xbuild = rustPlatform.buildRustPackage rec {
+        pname = "cargo-xbuild";
+        version = "0.6.5";
+
+        src = pkgs.fetchFromGitHub {
+          owner = "rust-osdev";
+          repo = pname;
+          rev = "v${version}";
+          sha256 = "18djvygq9v8rmfchvi2hfj0i6fhn36m716vqndqnj56fiqviwxvf";
+        };
+        cargoSha256 = "13sj9j9kl6js75h9xq0yidxy63vixxm9q3f8jil6ymarml5wkhx8";
+
+        meta = with pkgs.lib; {
+          description = "Automatically cross-compiles the sysroot crates core, compiler_builtins, and alloc";
+          homepage = "https://github.com/rust-osdev/cargo-xbuild";
+          license = with licenses; [ mit asl20 ];
+          maintainers = with maintainers; [ johntitor xrelkd ];
+        };
+      };

      mkbootimage = pkgs.stdenv.mkDerivation {
        pname = "mkbootimage";
-        version = "2.3dev";
+        version = "2.2";

        src = pkgs.fetchFromGitHub {
          owner = "antmicro";
          repo = "zynq-mkbootimage";
-          rev = "872363ce32c249f8278cf107bc6d3bdeb38d849f";
-          sha256 = "sha256-5FPyAhUWZDwHbqmp9J2ZXTmjaXPz+dzrJMolaNwADHs=";
+          rev = "4ee42d782a9ba65725ed165a4916853224a8edf7";
+          sha256 = "1k1mbsngqadqihzjgvwvsrkvryxy5ladpxd9yh9iqn2s7fxqwqa9";
        };

        propagatedBuildInputs = [ pkgs.libelf pkgs.pcre ];
@ -61,7 +180,6 @@
          mkdir -p $out/bin
          cp mkbootimage $out/bin
        '';
-        hardeningDisable = [ "fortify" ];
      };

      fsbl = { board ? "zc706" }: pkgs.stdenv.mkDerivation {
@ -69,20 +187,19 @@
        src = pkgs.fetchFromGitHub {
          owner = "Xilinx";
          repo = "embeddedsw";
-          rev = "xilinx_v2022.2";
-          sha256 = "sha256-UDz9KK/Hw3qM1BAeKif30rE8Bi6C2uvuZlvyvtJCMfw=";
+          rev = "65c849ed46c88c67457e1fc742744f96db968ff1";
+          sha256 = "1rvl06ha40dzd6s9aa4sylmksh4xb9dqaxq462lffv1fdk342pda";
        };
+        patches = [ ./fsbl.patch ];
        nativeBuildInputs = [
-          pkgs.pkgsCross.zynq-baremetal.buildPackages.binutils
-          pkgs.pkgsCross.zynq-baremetal.buildPackages.gcc
+          pkgs.gnumake
+          gnutoolchain.binutils
+          gnutoolchain.gcc
        ];
        patchPhase = ''
+          patch -p1 -i ${./fsbl.patch}
          patchShebangs lib/sw_apps/zynq_fsbl/misc/copy_bsp.sh
-
-          for x in lib/sw_apps/zynq_fsbl/src/Makefile lib/sw_apps/zynq_fsbl/misc/copy_bsp.sh lib/bsp/standalone/src/arm/cortexa9/gcc/Makefile; do
-            substituteInPlace $x \
-              --replace "arm-none-eabi-" "arm-none-eabihf-"
-          done
+          echo 'SEARCH_DIR("${gnutoolchain.newlib}/arm-none-eabi/lib");' >> lib/sw_apps/zynq_fsbl/src/lscript.ld
        '';
        buildPhase = ''
          cd lib/sw_apps/zynq_fsbl/src
@ -96,10 +213,6 @@
        dontFixup = true;
      };

-      cargo-xbuild = pkgs.cargo-xbuild.overrideAttrs(oa: {
-        postPatch = "substituteInPlace src/sysroot.rs --replace 2021 2018";
-      });
-
      build-crate = name: crate: features: rustPlatform.buildRustPackage rec {
        name = "${crate}";

@ -108,9 +221,9 @@
        ) ./.;
        cargoLock = { lockFile = ./Cargo.lock; };

-        nativeBuildInputs = [ cargo-xbuild pkgs.llvmPackages_14.clang-unwrapped ];
+        nativeBuildInputs = [ cargo-xbuild pkgs.llvmPackages_9.clang-unwrapped ];
        buildPhase = ''
-          export XARGO_RUST_SRC="${rust}/lib/rustlib/src/rust/library"
+          export XARGO_RUST_SRC="${rustPlatform.rust.rustc}/lib/rustlib/src/rust/library"
          export CARGO_HOME=$(mktemp -d cargo-home.XXX)
          pushd ${crate}
          cargo xbuild --release --frozen \
@ -127,7 +240,6 @@

        doCheck = false;
        dontFixup = true;
-        auditable = false;
      };

      targetCrates = target: {
@ -153,20 +265,21 @@

      hydraJobs = packages.x86_64-linux;

-      inherit rust rustPlatform;
+      inherit rustPlatform;

      devShell.x86_64-linux = pkgs.mkShell {
        name = "zynq-rs-dev-shell";
-        buildInputs = [
-          rust
+        buildInputs = with pkgs; [
+          rustPlatform.rust.rustc
+          rustPlatform.rust.cargo
+          cacert
          cargo-xbuild
-          mkbootimage

-          pkgs.openocd pkgs.gdb
-          pkgs.openssh pkgs.rsync
-          pkgs.llvmPackages_14.clang-unwrapped
-          (pkgs.python3.withPackages(ps: [ ps.pyftdi ]))
-        ];
-      };
+          openocd gdb
+          openssh rsync
+          llvmPackages_9.clang-unwrapped
+          (python3.withPackages(ps: [ ps.pyftdi ]))
+          mkbootimage ];
+        };
    };
-}
+}
--- a/fsbl.patch
+++ b/fsbl.patch
@ -0,0 +1,31 @@
+diff --git a/lib/sw_apps/zynq_fsbl/src/Makefile b/lib/sw_apps/zynq_fsbl/src/Makefile
+index 0e3ccdf1c5..a5b02f386e 100644
+--- a/lib/sw_apps/zynq_fsbl/src/Makefile
+++ b/lib/sw_apps/zynq_fsbl/src/Makefile
+@@ -71,11 +71,14 @@ endif
+ all: $(EXEC)
+ 
+ $(EXEC): $(LIBS) $(OBJS) $(INCLUDES)
+-	cp $(BSP_DIR)/$(BOARD)/ps7_init.* .
+ 	$(LINKER) $(LD1FLAGS)  -o $@ $(OBJS) $(LDFLAGS)
+ 	rm -rf $(OBJS)
+-	
+-	
+
+.PHONY: ps7_init
+
+ps7_init:
+	cp $(BSP_DIR)/$(BOARD)/ps7_init.* .
+
+ $(LIBS): 
+ 	echo "Copying BSP files"
+ 	$(BSP_DIR)/copy_bsp.sh $(BOARD) $(CC)
+@@ -86,7 +89,7 @@ $(LIBS):
+         make -C $(BSP_DIR) -k all "CC=armcc" "AR=armar" "C_FLAGS= -O2 -c" "EC_FLAGS=--debug --wchar32"; \
+ 	fi;
+ 
+-%.o:%.c
+%.o:%.c ps7_init
+ 	$(CC) $(CC_FLAGS) $(CFLAGS) $(ECFLAGS) -c $< -o $@ $(INCLUDEPATH)
+ 
+ %.o:%.S
--- a/libboard_zynq/src/error_led.rs
+++ b/libboard_zynq/src/error_led.rs
@ -18,6 +18,8 @@ impl ErrorLED {
                    .pullup(true)
                    .disable_rcvr(true)
            );
+            // reset
+            slcr.gpio_rst_ctrl.reset_gpio();
        });

        Self::error_led_common(0xFFFF - 0x0080)
--- a/libboard_zynq/src/eth/mod.rs
+++ b/libboard_zynq/src/eth/mod.rs
@ -13,9 +13,6 @@ mod regs;
 pub mod rx;
 pub mod tx;

-use super::time::Milliseconds;
-use embedded_hal::timer::CountDown;
-
 /// Size of all the buffers
 pub const MTU: usize = 1536;
 /// Maximum MDC clock
@ -303,18 +300,11 @@ impl<GEM: Gem> Eth<GEM, (), ()> {
    fn gem_common(macaddr: [u8; 6]) -> Self {
        GEM::setup_clock(TX_1000);

-        #[cfg(feature="target_kasli_soc")]
-        {
-            let mut eth_reset_pin = PhyRst::rst_pin();
-            eth_reset_pin.reset();
-        }
-
        let mut inner = EthInner {
            gem: PhantomData,
            link: None,
        };
        inner.init();
-
        inner.configure(macaddr);

        let phy = Phy::find(&mut inner).expect("phy");
@ -492,69 +482,6 @@ impl<'a, GEM: Gem> smoltcp::phy::Device<'a> for &mut Eth<GEM, rx::DescList, tx::
    }
 }

-pub struct PhyRst {
-    regs: regs::GpioRegisterBlock,
-    count_down: super::timer::global::CountDown<Milliseconds>,
-}
-
-impl PhyRst {
-    pub fn rst_pin() -> Self {
-        slcr::RegisterBlock::unlocked(|slcr| {
-            // Hardware Reset for PHY
-            slcr.mio_pin_47.write(
-                slcr::MioPin47::zeroed()
-                    .l3_sel(0b000)
-                    .io_type(slcr::IoBufferType::Lvcmos18)
-                    .pullup(true)
-                    .disable_rcvr(true)
-            );
-        });
-        Self::eth_reset_common(0xFFFF - 0x8000)
-    }
-    
-    fn delay_ms(&mut self, ms: u64) {
-        self.count_down.start(Milliseconds(ms));
-        nb::block!(self.count_down.wait()).unwrap();
-    }
-
-    fn eth_reset_common(gpio_output_mask: u16) -> Self {
-        let self_ = Self {
-            regs: regs::GpioRegisterBlock::regs(),
-            count_down: unsafe { super::timer::GlobalTimer::get() }.countdown(),
-        };
-
-        // Setup GPIO output mask
-        self_.regs.gpio_output_mask.modify(|_, w| {
-            w.mask(gpio_output_mask)
-        });
-
-        self_.regs.gpio_direction.modify(|_, w| {
-            w.phy_rst(true)
-        });
-        
-        self_
-    }
-
-    fn oe(&mut self, oe: bool) {
-        self.regs.gpio_output_enable.modify(|_, w| {
-            w.phy_rst(oe)
-        })
-    }
-
-    fn toggle(&mut self, o: bool) {
-        self.regs.gpio_output_mask.modify(|_, w| {
-            w.phy_rst(o)
-        })
-    }
-
-    pub fn reset(&mut self) {
-        self.toggle(false); // drive phy_rst (active LOW) pin low
-        self.oe(true);         // enable pin's output
-        self.delay_ms(10);
-        self.toggle(true);
-    }
-}
-

 struct EthInner<GEM: Gem> {
    gem: PhantomData<GEM>,
--- a/libboard_zynq/src/eth/regs.rs
+++ b/libboard_zynq/src/eth/regs.rs
@ -110,49 +110,6 @@ pub struct RegisterBlock {
    pub design_cfg5: RO<u32>,
 }

-pub struct GpioRegisterBlock {
-    pub gpio_output_mask: &'static mut OutputMask,
-    pub gpio_direction: &'static mut Direction,
-    pub gpio_output_enable: &'static mut OutputEnable,
-}
-
-impl GpioRegisterBlock {
-    pub fn regs() -> Self {
-        Self {
-            gpio_output_mask: OutputMask::new(),
-            gpio_direction: Direction::new(),
-            gpio_output_enable: OutputEnable::new(),
-        }
-    }
-}
-
-register!(gpio_output_mask, 
-            /// MASK_DATA_1_SW:
-            /// Maskable output data for MIO[47:32]
-            OutputMask, RW, u32);
-register_at!(OutputMask, 0xE000A008, new);
-register_bit!(gpio_output_mask, 
-            /// Output for PHY_RST (MIO[47])
-            phy_rst, 15);
-register_bits!(gpio_output_mask,
-            mask, u16, 16, 31);
-register!(gpio_direction, 
-            /// DIRM_1:
-            /// Direction mode for MIO[53:32]; 0/1 = in/out
-            Direction, RW, u32);
-register_at!(Direction, 0xE000A244, new);
-register_bit!(gpio_direction,
-            /// Direction for PHY_RST
-            phy_rst, 15);
-register!(gpio_output_enable,
-            /// OEN_1:
-            /// Output enable for MIO[53:32]
-            OutputEnable, RW, u32);
-register_at!(OutputEnable, 0xE000A248, new);
-register_bit!(gpio_output_enable,
-            /// Output enable for PHY_RST
-            phy_rst, 15);
-    
 register_at!(RegisterBlock, 0xE000B000, gem0);
 register_at!(RegisterBlock, 0xE000C000, gem1);

--- a/libboard_zynq/src/gic.rs
+++ b/libboard_zynq/src/gic.rs
@ -115,7 +115,7 @@ impl InterruptController {
        let m = (id.0 >> 2) as usize;
        let n = (8 * (id.0 & 3)) as usize;
        unsafe {
-            self.mpcore.icdiptr[m].modify(|mut icdiptr| *icdiptr.set_bits(n..=n+1, target_cpu as u32));
+            self.mpcore.icdiptr[m].modify(|mut icdiptr| *icdiptr.set_bits(n..=n+1, target_cpu as u32 + 1));
        }

        // sensitivity
--- a/libboard_zynq/src/i2c/mod.rs
+++ b/libboard_zynq/src/i2c/mod.rs
@ -53,6 +53,8 @@ impl I2c {
                    .pullup(false)
                    .disable_rcvr(true)
            );
+            // Reset
+            slcr.gpio_rst_ctrl.reset_gpio();
        });

        Self::i2c_common(0xFFFF - 0x000C, 0xFFFF - 0x0002)
--- a/libcortex_a9/src/asm.rs
+++ b/libcortex_a9/src/asm.rs
@ -34,12 +34,6 @@ pub fn isb() {
    unsafe { llvm_asm!("isb" :::: "volatile") }
 }

-/// Enable FIQ
-#[inline]
-pub unsafe fn enable_fiq() {
-    llvm_asm!("cpsie f":::: "volatile");
-}
-
 /// Enable IRQ
 #[inline]
 pub unsafe fn enable_irq() {
--- a/libcortex_a9/src/lib.rs
+++ b/libcortex_a9/src/lib.rs
@ -36,9 +36,7 @@ pub fn notify_spin_lock() {
 }

 #[macro_export]
-/// Interrupt handler, which setup the stack and preserve registers before jumping to actual interrupt handler.
-/// Registers r0-r12, PC, SP and CPSR are restored after the actual handler.
-/// 
+/// Interrupt handler, which setup the stack and jump to actual interrupt handler.
 /// - `name` is the name of the interrupt, should be the same as the one defined in vector table.
 /// - `name2` is the name for the actual handler, should be different from name.
 /// - `stack0` is the stack for the interrupt handler when called from core0.
@ -46,7 +44,8 @@ pub fn notify_spin_lock() {
 /// - `body` is the body of the actual interrupt handler, should be a normal unsafe rust function
 /// body.
 ///
-/// Note that the interrupt handler would use the same stack as normal programs by default.
+/// Note that the interrupt handler would use the same stack as normal programs by default, so
+/// interrupt handlers should not return to normal program or it may corrupt the stack.
 macro_rules! interrupt_handler {
    ($name:ident, $name2:ident, $stack0:ident, $stack1:ident, $body:block) => {
        #[link_section = ".text.boot"]
@ -55,27 +54,19 @@ macro_rules! interrupt_handler {
        pub unsafe extern "C" fn $name() -> ! {
            asm!(
                // setup SP, depending on CPU 0 or 1
-                // and preserve registers
-                "sub lr, lr, #4",
-                "stmfd sp!, {{r0-r12, lr}}",
                "mrc p15, #0, r0, c0, c0, #5",
                concat!("movw r1, :lower16:", stringify!($stack0)),
                concat!("movt r1, :upper16:", stringify!($stack0)),
                "tst r0, #3",
                concat!("movwne r1, :lower16:", stringify!($stack1)),
                concat!("movtne r1, :upper16:", stringify!($stack1)),
-                "mov r0, sp",
                "mov sp, r1",
-                "push {{r0, r1}}",                                      // 2 registers are pushed to maintain 8 byte stack alignment 
                concat!("bl ", stringify!($name2)),
-                "pop {{r0, r1}}",
-                "mov sp, r0",
-                "ldmfd sp!, {{r0-r12, pc}}^",                           // caret ^ : copy SPSR to the CPSR  
                options(noreturn)
            );
        }

        #[no_mangle]
-        pub unsafe extern "C" fn $name2() $body
+        pub unsafe extern "C" fn $name2() -> ! $body
    };
 }
--- a/libsupport_zynq/Cargo.toml
+++ b/libsupport_zynq/Cargo.toml
@ -12,10 +12,9 @@ target_redpitaya = ["libboard_zynq/target_redpitaya"]
 target_kasli_soc = ["libboard_zynq/target_kasli_soc"]
 panic_handler = []
 dummy_irq_handler = []
-dummy_fiq_handler = []
 alloc_core = []

-default = ["panic_handler", "dummy_irq_handler", "dummy_fiq_handler"]
+default = ["panic_handler", "dummy_irq_handler"]

 [dependencies]
 r0 = "1"
--- a/libsupport_zynq/src/exception_vectors.rs
+++ b/libsupport_zynq/src/exception_vectors.rs
@ -1,10 +1,6 @@
-use libregister::{RegisterR, RegisterW};
-use libcortex_a9::{regs::{DFSR, MPIDR, VBAR}, interrupt_handler};
-use libboard_zynq::{println, stdio}; 
-
-pub fn set_vector_table(base_addr: u32){
-    VBAR.write(base_addr);
-}
+use libregister::RegisterR;
+use libcortex_a9::{regs::{DFSR, MPIDR}, interrupt_handler};
+use libboard_zynq::{println, stdio};

 interrupt_handler!(UndefinedInstruction, undefined_instruction, __irq_stack0_start, __irq_stack1_start, {
    stdio::drop_uart();
@ -46,7 +42,6 @@ interrupt_handler!(IRQ, irq, __irq_stack0_start, __irq_stack1_start, {
    loop {}
 });

-#[cfg(feature = "dummy_fiq_handler")]
 interrupt_handler!(FIQ, fiq, __irq_stack0_start, __irq_stack1_start, {
    stdio::drop_uart();
    println!("FIQ");
--- a/libsupport_zynq/src/boot.rs
+++ b/libsupport_zynq/src/boot.rs
@ -54,7 +54,6 @@ unsafe extern "C" fn boot_core0() -> ! {
        asm::dmb();
        asm::dsb();

-        asm::enable_fiq();
        asm::enable_irq();
        main_core0();
        panic!("return from main");
@ -76,7 +75,6 @@ unsafe extern "C" fn boot_core1() -> ! {
        asm::dmb();
        asm::dsb();

-        asm::enable_fiq();
        asm::enable_irq();
        main_core1();
        panic!("return from main_core1");
--- a/libsupport_zynq/src/lib.rs
+++ b/libsupport_zynq/src/lib.rs
@ -9,7 +9,7 @@ pub extern crate alloc;
 pub extern crate compiler_builtins;

 pub mod boot;
-pub mod exception_vectors;
+mod abort;
 #[cfg(feature = "panic_handler")]
 mod panic;
 pub mod ram;