added openMZ

openMZ/.clang-format

+---
+Language:        Cpp
+# BasedOnStyle:  WebKit
+AccessModifierOffset: -4
+AlignAfterOpenBracket: DontAlign
+AlignConsecutiveMacros: false
+AlignConsecutiveAssignments: false
+AlignConsecutiveDeclarations: false
+AlignEscapedNewlines: Right
+AlignOperands:   false
+AlignTrailingComments: false
+AllowAllArgumentsOnNextLine: true
+AllowAllConstructorInitializersOnNextLine: true
+AllowAllParametersOfDeclarationOnNextLine: true
+AllowShortBlocksOnASingleLine: false
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: None 
+AllowShortLambdasOnASingleLine: All
+AllowShortIfStatementsOnASingleLine: Never
+AllowShortLoopsOnASingleLine: false
+AlwaysBreakAfterDefinitionReturnType: None
+AlwaysBreakAfterReturnType: None
+AlwaysBreakBeforeMultilineStrings: false
+AlwaysBreakTemplateDeclarations: MultiLine
+BinPackArguments: true
+BinPackParameters: true
+BraceWrapping:
+  AfterCaseLabel:  false
+  AfterClass:      false
+  AfterControlStatement: false
+  AfterEnum:       false
+  AfterFunction:   true
+  AfterNamespace:  false
+  AfterObjCDeclaration: false
+  AfterStruct:     false
+  AfterUnion:      false
+  AfterExternBlock: false
+  BeforeCatch:     false
+  BeforeElse:      false
+  IndentBraces:    false
+  SplitEmptyFunction: true
+  SplitEmptyRecord: true
+  SplitEmptyNamespace: true
+BreakBeforeBinaryOperators: All
+BreakBeforeBraces: WebKit
+BreakBeforeInheritanceComma: false
+BreakInheritanceList: BeforeColon
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializersBeforeComma: false
+BreakConstructorInitializers: BeforeComma
+BreakAfterJavaFieldAnnotations: false
+BreakStringLiterals: true
+ColumnLimit:     0
+CommentPragmas:  '^ IWYU pragma:'
+CompactNamespaces: false
+ConstructorInitializerAllOnOneLineOrOnePerLine: false
+ConstructorInitializerIndentWidth: 4
+ContinuationIndentWidth: 4
+Cpp11BracedListStyle: false
+DerivePointerAlignment: false
+DisableFormat:   false
+ExperimentalAutoDetectBinPacking: false
+FixNamespaceComments: false
+ForEachMacros:
+  - foreach
+  - Q_FOREACH
+  - BOOST_FOREACH
+IncludeBlocks:   Preserve
+IncludeCategories:
+  - Regex:           '^"(llvm|llvm-c|clang|clang-c)/'
+    Priority:        2
+  - Regex:           '^(<|"(gtest|gmock|isl|json)/)'
+    Priority:        3
+  - Regex:           '.*'
+    Priority:        1
+IncludeIsMainRegex: '(Test)?$'
+IndentCaseLabels: false
+IndentPPDirectives: None
+IndentWidth:     4
+IndentWrappedFunctionNames: false
+JavaScriptQuotes: Leave
+JavaScriptWrapImports: true
+KeepEmptyLinesAtTheStartOfBlocks: true
+MacroBlockBegin: ''
+MacroBlockEnd:   ''
+MaxEmptyLinesToKeep: 1
+NamespaceIndentation: Inner
+ObjCBinPackProtocolList: Auto
+ObjCBlockIndentWidth: 4
+ObjCSpaceAfterProperty: true
+ObjCSpaceBeforeProtocolList: true
+PenaltyBreakAssignment: 2
+PenaltyBreakBeforeFirstCallParameter: 19
+PenaltyBreakComment: 300
+PenaltyBreakFirstLessLess: 120
+PenaltyBreakString: 1000
+PenaltyBreakTemplateDeclaration: 10
+PenaltyExcessCharacter: 1000000
+PenaltyReturnTypeOnItsOwnLine: 60
+PointerAlignment: Left
+ReflowComments:  true
+SortIncludes:    true
+SortUsingDeclarations: true
+SpaceAfterCStyleCast: false
+SpaceAfterLogicalNot: false
+SpaceAfterTemplateKeyword: true
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeCpp11BracedList: true
+SpaceBeforeCtorInitializerColon: true
+SpaceBeforeInheritanceColon: true
+SpaceBeforeParens: ControlStatements
+SpaceBeforeRangeBasedForLoopColon: true
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 1
+SpacesInAngles:  false
+SpacesInContainerLiterals: true
+SpacesInCStyleCastParentheses: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+Standard:        Cpp11
+StatementMacros:
+  - Q_UNUSED
+  - QT_REQUIRE_VERSION
+TabWidth:        4
+UseTab:          Never
+...
+

openMZ/.gitignore

+# Compile results
+*.elf
+*.map
+*.hex
+
+# Eclipse project
+.cproject
+.project
+.settings
+
+# ctags database
+tags

openMZ/LICENSE

+This project is under three different copyright licenses:
+
+ - HexFive's license (LICENSE.HEXFIVE) for the MultiZone API (libhexfive.h).
+ - GPLv2 (LICENSE.GPLv2) for the kernel and drivers. 
+ - MIT (LICENSE.MIT) for the kernel configuration. 
+
+The owner of the copyright of the source files are on the top of each file.

openMZ/LICENSE.GPLv2

+Files described as being under the "GNU General Public License version 2"
+or simply the "GPLv2" fall under the license below.
+
+The copyrights of the GPLv2 licensed files of the project are held by the
+respective owners indicated at the top of the file.
+
+The Free Software Foundation owns the copyright to the license below.
+
+---------------------------------------------------------------------
+
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
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+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
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+  1. You may copy and distribute verbatim copies of the Program's
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+  2. You may modify your copy or copies of the Program or any portion
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+                            NO WARRANTY
+
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+                     END OF TERMS AND CONDITIONS
+
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+    it under the terms of the GNU General Public License as published by
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+
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+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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+    This is free software, and you are welcome to redistribute it
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+
+The hypothetical commands `show w' and `show c' should show the appropriate
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+
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+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.

openMZ/LICENSE.HEXFIVE

+The file "libhexfive.h" falls under the following license.
+
+-------------------------------------------------------------------------------------------------------
+
+                                Copyright (c) 2018, Hex Five Security, Inc.
+
+Permission to use, copy, modify, and/or distribute this software for any purpose with or without 
+fee is hereby granted, provided that the above copyright notice and this permission notice appear 
+in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
+INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE 
+FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 
+LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, 
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

openMZ/LICENSE.MIT

+Files described as being under the "MIT License"
+or simply the "MIT" fall under the license below.
+
+The copyrights of the MIT licensed files of the project are held by the
+respective owners indicated at the top of the file.
+
+---------------------------------------------------------------------
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

openMZ/Makefile

+#  
+# Copyright 2020, Saab AB
+#  
+# This software may be distributed and modified according to
+# the terms of the MIT License.
+# Note that NO WARRANTY is provided.
+# See "LICENSE.MIT" for details.
+#  
+
+PROGRAMS = openmz zone1 zone2
+
+BOARD ?= fe310
+BSP_DIR = $(abspath bsp/$(BOARD))
+include $(BSP_DIR)/settings.mk
+
+HEXFIVE_DIR = $(abspath libhexfive)
+
+ELF_DIR = $(abspath elf)
+HEX_DIR = $(abspath hex)
+
+export CC=riscv64-unknown-elf-gcc
+export SIZE=riscv64-unknown-elf-size
+export OBJCOPY=riscv64-unknown-elf-objcopy
+export OBJDUMP=riscv64-unknown-elf-objdump
+
+.PHONY: all
+all: compile 
+
+.PHONY: compile
+.PHONY: clean
+.PHONY: upload
+ifeq ($(PROGRAM),)
+compile:
+	for file in $(PROGRAMS) ; do \
+	    $(MAKE) -C . compile PROGRAM=$$file ; \
+	done
+clean:
+	for file in $(PROGRAMS) ; do \
+	    $(MAKE) -C . clean PROGRAM=$$file ; \
+	done
+upload:
+	for file in $(PROGRAMS) ; do \
+	    $(MAKE) -C . upload PROGRAM=$$file ; \
+	done
+else
+
+PROGRAM_ELF = $(ELF_DIR)/$(PROGRAM).elf
+PROGRAM_HEX = $(HEX_DIR)/$(PROGRAM).hex
+
+compile: $(PROGRAM_ELF) $(PROGRAM_HEX)
+
+.PHONY: $(PROGRAM_ELF)
+$(PROGRAM_ELF):
+	mkdir -p $(ELF_DIR)
+	$(MAKE) -C src/$(PROGRAM) compile \
+	    PROGRAM_ELF=$(PROGRAM_ELF) \
+	    BSP_DIR=$(BSP_DIR) \
+	    HEXFIVE_DIR=$(HEXFIVE_DIR)
+
+$(PROGRAM_HEX): $(PROGRAM_ELF)
+	mkdir -p $(HEX_DIR)
+	$(OBJCOPY) -O ihex $(PROGRAM_ELF) $(PROGRAM_HEX)
+
+upload: $(PROGRAM_HEX)
+	echo "loadfile $(PROGRAM_HEX)\nexit" \
+	    | JLinkExe -device fe310 -if JTAG -speed 4000 -jtagconf -1,-1 -autoconnect 1
+
+clean:
+	rm -f $(PROGRAM_ELF)
+endif
+
+

openMZ/README.md

+# OpenMZ 
+OpenMZ is an open-source implementation of [HexFive's MultiZone API](https://github.com/hex-five/multizone-api). 
+
+OpenMZ is a security kernel for RISC-V processors with machine-mode and user-mode. OpenMZ partitions a system into an unlimited number of zones. Each zone has full access to eight regions of memory-mapped I/O (e.g., RAM, UART, GPIO), protected using RISC-V's physical memory protection (PMP) mechanism.
+
+## Features
+- Preemptive round-robin scheduler with a configurable time slices.
+- Self-contained and open-source, written in C and assembly.
+- Theoretically unlimited number of *spatially* isolated zones.
+- Up to eight memory-mapped I/O regions per zone with protections defined by you.
+- Support for user-mode platform-level and core-local interrupts.
+- Support for user-mode exception handling.
+- A secure user-mode timer interrupts emulation.
+- Fast register-based inter-zone communication.
+
+## Attacker model
+- **Data attack.** A zone tries to access or modify the memory in an unauthorized manner.
+- **Timing attack.** A zone tries to infer information from another zone or the kernel using timing side-channel attacks.
+- **Cache attack.** A zone tries to infer information from another zone or the kernel using cache side-channel attacks.
+
+## Kernel configuration
+The kernel's configurations is in [config.h](openmz/config.h). The PMP fields `pmpcfg0` and `pmpaddr[0-8]` are configured as in RISC-V's PMP registers `pmpcfg0` and `pmpaddr0-7`. The initial program counter is stored in `regs[0]`. Interrupt mappings are stored in the `irq_handlers` field. All of these configurations options are set in `config.h`.
+```C
+/* ... */
+/* number of zone */
+#define N_ZONES 3 
+
+/* max trap code */
+#define N_TRAPS 12
+
+/* max interrupt code */
+#define N_INTERRUPTS 12
+
+/* time slice in timer cycles */
+#define QUANTUM (32768 / 100)
+
+/* Zone configuration */
+/* ZONE(program counter, pmpcfg0, {pmpaddr0, ..., pmpaddr7}) */
+#define ZONE_CONFIG             \
+    ZONE(0x20020000, ..., ...) \
+    ZONE(0x20030000, ..., ...) \
+    ZONE(0x20040000, ..., ...)
+
+/* Mapping interrupts to zones */
+/* IRQ(zone id, interrupt exception code) */
+#define IRQ_CONFIG IRQ(1, 11) IRQ(2, 18)
+/* ... */
+```
+
+## (Potential) Future Work
+- Complete formal verification - from the hardware level to source code.
+- Implement `ECALL_WFI`.
+- `YIELD_TO` call - allowing zones to yield their remaining time slice to a specific zone.
+- An optional *temporal* isolation of zones by disabling `YIELD/WFI` calls, and immediate context switch for interrupts.
+- More advanced round-robin scheduling with more configurable zone order and time slices.
+- Compatibility with a secure bootloader, or a new secure bootloader.
+- System call for supporting remote attestation.
+- RISC-V user-interrupt extension (N extension) compatibility.
+- Multicore support.
+- Supervisor support.
+- More memory-mapped I/O regions per zone.
+- Inter-processor communication (IPC) - allowing communication with a Linux companion on a different core.
+
+*The above list is mostly sorted by priority.*
+## Example zone implementation
+
+## Attribution
+
+## Copyright
+
+This project is under three different copyright licenses. HexFive's license for the MultiZone API (`libhexfive.h`), GPLv2 for the kernel and drivers, and MIT for the kernel configuration. The owner of the copyright of a source file is on the top.

openMZ/bsp/fe310/machine.h

+/**
+ * Copyright 2020, Saab AB
+ *
+ * This software may be distributed and modified according to 
+ * the terms of the GNU General Public License version 2. 
+ * Note that NO WARRANTY is provided.
+ * See "LICENSE.GPLv2" for details.
+ */
+#ifndef MACHINE_H
+#define MACHINE_H
+#include "csr.h"
+#include <platform.h>
+
+static inline uint64_t read_mtime(void)
+{
+    register uint32_t lo, hi1, hi2;
+    do {
+        hi1 = CLIC.mtimeh;
+        lo = CLIC.mtime;
+        hi2 = CLIC.mtimeh;
+    } while (hi1 != hi2);
+    return (uint64_t)hi1 << 32 | lo;
+}
+
+static inline void write_mtimecmp(uint64_t val)
+{
+    CLIC.mtimecmp = -1;
+    CLIC.mtimecmph = val >> 32;
+    CLIC.mtimecmp = val;
+}
+
+static inline void clear_cache(void)
+{
+    // no cache clearing
+}
+
+static inline void init_hardware(void)
+{
+    // Sets core clock frequency to 16 MHz
+    uint32_t pllr = 0x1;
+    uint32_t pllf = 0x2F;
+    uint32_t pllq = 0x2;
+    uint32_t pllsel = 0x1;
+    uint32_t pllrefsel = 0x1;
+    uint32_t pllbypass = 0x0;
+    PRCI.pllcfg = pllr | (pllf << 4) | (pllq << 10) | (pllsel << 16) | (pllrefsel << 17) | (pllbypass << 18);
+    while (!(PRCI.pllcfg >> 31))
+        ; // wait until configuration is locked
+
+    CSRW(mcounteren, 0x1F);
+    CSRW(mhpmevent3, 0x0102);
+}
+
+#endif // MACHINE_H

openMZ/bsp/fe310/memory.lds

+/**
+ * Copyright 2020, Saab AB
+ *
+ * This software may be distributed and modified according to 
+ * the terms of the GNU General Public License version 2. 
+ * Note that NO WARRANTY is provided.
+ * See "LICENSE.GPLv2" for details.
+ */
+rom = 0x20000000;
+ram = 0x80000000;
+itim = 0x8000000;
+
+CLIC  = 0x02000000;
+PLIC  = 0x0C000000;
+PRCI  = 0x10008000;
+GPIO  = 0x10012000;
+UART0 = 0x10013000;
+UART1 = 0x10023000;

openMZ/bsp/fe310/platform.h

+/**
+ * Copyright 2020, Saab AB
+ *
+ * This software may be distributed and modified according to 
+ * the terms of the GNU General Public License version 2. 
+ * Note that NO WARRANTY is provided.
+ * See "LICENSE.GPLv2" for details.
+ */
+#ifndef PLATFORM_H
+#define PLATFORM_H
+#include <stdint.h>
+
+#define RTCK_FREQ 32768
+#define CORECLK_FREQ 192000000
+
+// Padding so struct fields align correctly to memory map
+#define _PAD(name, start, end) char name[end - start]
+
+typedef volatile struct clic {
+    uint32_t msip;
+    _PAD(pad1, 0x4, 0x4000);
+    uint32_t mtimecmp;
+    uint32_t mtimecmph;
+    _PAD(pad2, 0x4008, 0xbff8);
+    uint32_t mtime;
+    uint32_t mtimeh;
+} clic_t;
+
+typedef volatile struct plic {
+    _PAD(pad1, 0x0, 0x4);
+    uint32_t source_prio[52];
+    _PAD(pad2, 0xD4, 0x1000);
+    uint32_t pending[2];
+    _PAD(pad3, 0x1008, 0x2000);
+    uint32_t ie[2];
+    _PAD(pad4, 0x2008, 0x200000);
+    uint32_t prio_thres;
+    uint32_t claim_complete;
+} plic_t;
+
+typedef volatile struct gpio {
+    uint32_t input_val;
+    uint32_t input_en;
+    uint32_t output_val;
+    uint32_t output_en;
+    uint32_t pue;
+    uint32_t ds;
+    uint32_t rise_ie;
+    uint32_t rise_ip;
+    uint32_t fall_ie;
+    uint32_t fall_ip;
+    uint32_t high_ie;
+    uint32_t high_ip;
+    uint32_t low_ie;
+    uint32_t low_ip;
+    uint32_t iof_en;
+    uint32_t iof_sel;
+    uint32_t out_xor;
+} gpio_t;
+
+typedef volatile struct uart {
+    int32_t txdata;
+    int32_t rxdata;
+    uint32_t txctrl;
+    uint32_t rxctrl;
+    uint32_t ie;
+    uint32_t ip;
+    uint32_t div;
+} uart_t;
+
+typedef volatile struct prci {
+    uint32_t hfrosccfg;
+    uint32_t hfxosccfg;
+    uint32_t pllcfg;
+    uint32_t plloutdiv;
+    uint32_t procmoncfg;
+} prci_t;
+
+extern clic_t CLIC;
+extern plic_t PLIC;
+extern prci_t PRCI;
+extern gpio_t GPIO;
+extern uart_t UART0;
+extern uart_t UART1;
+#endif // PLATFORM_H

openMZ/bsp/fe310/settings.mk

+export ARCH = rv32imac
+export ABI = ilp32
+export CMODEL = medlow

openMZ/libhexfive/libhexfive.S

+/**
+ * Copyright 2020, Saab AB
+ *
+ * This software may be distributed and modified according to 
+ * the terms of the GNU General Public License version 2. 
+ * Note that NO WARRANTY is provided.
+ * See "LICENSE.GPLv2" for details.
+ */
+
+#define ENTRY(x) \
+.globl x; \
+x:
+
+.section .text.libhexfive
+ENTRY(ECALL_YIELD)
+        li      a7, 0           # sys call #0
+        ecall
+        ret
+
+ENTRY(ECALL_WFI)
+        li      a7, 1           # sys call #1
+        ecall
+        ret
+
+ENTRY(ECALL_SEND)
+#if __riscv_xlen == 32 
+        lw      a4, 12(a1)      # load msg[3]
+        lw      a3, 8(a1)       # load msg[2]
+        lw      a2, 4(a1)       # load msg[1]
+        lw      a1, 0(a1)       # load msg[0]
+#else
+        ld      a2, 8(a1)       # load msg[2-3]
+        ld      a1, 0(a1)       # load msg[0-1]
+#endif
+        li      a7, 2           # sys call #2
+        ecall
+        ret
+
+ENTRY(ECALL_RECV)
+        mv      a6, a1          # save pointer
+        li      a7, 3           # sys call #3
+        ecall
+        beqz    a0, 1f          # status == 0, go to ret
+#if __riscv_xlen == 32 
+        sw      a4, 12(a6)      # save msg[3]
+        sw      a3, 8(a6)       # save msg[2]
+        sw      a2, 4(a6)       # save msg[1]
+        sw      a1, 0(a6)       # save msg[0]
+#else
+        sd      a2, 8(a6)       # save msg[2-3]
+        sd      a1, 0(a6)       # save msg[0-1]
+#endif
+1:      ret
+
+ENTRY(ECALL_TRP_VECT)
+        li      a7, 4           # sys call #4
+        ecall
+        ret
+
+ENTRY(ECALL_IRQ_VECT)
+        li      a7, 5           # sys call #5
+        ecall
+        ret
+
+ENTRY(ECALL_CSRS_MIE)
+        li      a7, 6           # sys call #6
+        ecall
+        ret
+
+ENTRY(ECALL_CSRC_MIE)
+        li      a7, 7           # sys call #7
+        ecall
+        ret
+
+ENTRY(ECALL_CSRW_MTIMECMP)
+        li      a7, 8           # sys call #8
+        ecall
+        ret
+
+ENTRY(ECALL_CSRR_MTIME)
+        li      a7, 9           # sys call #9
+        ecall
+        ret
+
+ENTRY(ECALL_CSRR_MCYCLE)
+        li      a7, 10          # sys call #10
+        ecall
+        ret
+
+ENTRY(ECALL_CSRR_MINSTR)
+        li      a7, 11          # sys call #11
+        ecall
+        ret
+
+ENTRY(ECALL_CSRR_MHPMC3)
+        li      a7, 12          # sys call #12
+        ecall
+        ret
+
+ENTRY(ECALL_CSRR_MHPMC4)
+        li      a7, 13          # sys call #13
+        ecall
+        ret
+
+
+ENTRY(ECALL_CSRR_MISA)
+        li      a7, 14          # sys call #14
+        ecall
+        ret
+
+ENTRY(ECALL_CSRR_MVENDID)
+        li      a7, 15          # sys call #15
+        ecall
+        ret
+
+ENTRY(ECALL_CSRR_MARCHID)
+        li      a7, 16          # sys call #16
+        ecall
+        ret
+
+ENTRY(ECALL_CSRR_MIMPID)
+        li      a7, 17          # sys call #17
+        ecall
+        ret
+
+ENTRY(ECALL_CSRR_MHARTID)
+        li      a7, 18          # sys call #18
+        ecall
+        ret

openMZ/libhexfive/libhexfive.h

+/* Copyright(C) 2018 Hex Five Security, Inc. - All Rights Reserved */
+
+
+#ifndef LIBHEXFIVE_H_
+#define LIBHEXFIVE_H_
+#include <unistd.h>
+
+void ECALL_YIELD();
+void ECALL_WFI();
+
+int ECALL_SEND(int, void *);
+int ECALL_RECV(int, void *);
+
+void ECALL_TRP_VECT(int, void *);
+void ECALL_IRQ_VECT(int, void *);
+
+void ECALL_CSRS_MIE();
+void ECALL_CSRC_MIE();
+
+void ECALL_CSRW_MTIMECMP(uint64_t);
+
+uint64_t ECALL_CSRR_MTIME();
+uint64_t ECALL_CSRR_MCYCLE();
+uint64_t ECALL_CSRR_MINSTR();
+uint64_t ECALL_CSRR_MHPMC3();
+uint64_t ECALL_CSRR_MHPMC4();
+
+uint64_t ECALL_CSRR_MISA();
+uint64_t ECALL_CSRR_MVENDID();
+uint64_t ECALL_CSRR_MARCHID();
+uint64_t ECALL_CSRR_MIMPID();
+uint64_t ECALL_CSRR_MHARTID();
+
+#endif /* LIBHEXFIVE_H_ */

openMZ/scripts/COPYING

+This license applies to "git-pre-commit-format" and "apply-format."
+----
+Copyright 2017-2018 Marco Barisione <marco@barisione.org>
+Copyright 2018      Undo Ltd.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

openMZ/scripts/apply-format

+#! /bin/bash
+#
+# Copyright 2018 Undo Ltd.
+#
+# https://github.com/barisione/clang-format-hooks
+
+# Force variable declaration before access.
+set -u
+# Make any failure in piped commands be reflected in the exit code.
+set -o pipefail
+
+readonly bash_source="${BASH_SOURCE[0]:-$0}"
+
+##################
+# Misc functions #
+##################
+
+function error_exit() {
+    for str in "$@"; do
+        echo -n "$str" >&2
+    done
+    echo >&2
+
+    exit 1
+}
+
+
+########################
+# Command line parsing #
+########################
+
+function show_help() {
+    if [ -t 1 ] && hash tput 2> /dev/null; then
+        local -r b=$(tput bold)
+        local -r i=$(tput sitm)
+        local -r n=$(tput sgr0)
+    else
+        local -r b=
+        local -r i=
+        local -r n=
+    fi
+
+    cat << EOF
+${b}SYNOPSIS${n}
+
+    To reformat git diffs:
+
+        ${i}$bash_source [OPTIONS] [FILES-OR-GIT-DIFF-OPTIONS]${n}
+
+    To reformat whole files, including unchanged parts:
+
+        ${i}$bash_source [-f | --whole-file] FILES${n}
+
+${b}DESCRIPTION${n}
+
+    Reformat C or C++ code to match a specified formatting style.
+
+    This command can either work on diffs, to reformat only changed parts of
+    the code, or on whole files (if -f or --whole-file is used).
+
+    ${b}FILES-OR-GIT-DIFF-OPTIONS${n}
+        List of files to consider when applying clang-format to a diff. This is
+        passed to "git diff" as is, so it can also include extra git options or
+        revisions.
+        For example, to apply clang-format on the changes made in the last few
+        revisions you could use:
+            ${i}\$ $bash_source HEAD~3${n}
+
+    ${b}FILES${n}
+        List of files to completely reformat.
+
+    ${b}-f, --whole-file${n}
+        Reformat the specified files completely (including parts you didn't
+        change).
+        The fix is printed on stdout by default. Use -i if you want to modify
+        the files on disk.
+
+    ${b}--staged, --cached${n}
+        Reformat only code which is staged for commit.
+        The fix is printed on stdout by default. Use -i if you want to modify
+        the files on disk.
+
+    ${b}-i${n}
+        Reformat the code and apply the changes to the files on disk (instead
+        of just printing the fix on stdout).
+
+    ${b}--apply-to-staged${n}
+        This is like specifying both --staged and -i, but the formatting
+        changes are also staged for commit (so you can just use "git commit"
+        to commit what you planned to, but formatted correctly).
+
+    ${b}--style STYLE${n}
+        The style to use for reformatting code.
+        If no style is specified, then it's assumed there's a .clang-format
+        file in the current directory or one of its parents.
+
+    ${b}--help, -h, -?${n}
+        Show this help.
+EOF
+}
+
+# getopts doesn't support long options.
+# getopt mangles stuff.
+# So we parse manually...
+declare positionals=()
+declare has_positionals=false
+declare whole_file=false
+declare apply_to_staged=false
+declare staged=false
+declare in_place=false
+declare style=file
+declare ignored=()
+while [ $# -gt 0 ]; do
+    declare arg="$1"
+    shift # Past option.
+    case "$arg" in
+        -h | -\? | --help )
+            show_help
+            exit 0
+            ;;
+        -f | --whole-file )
+            whole_file=true
+            ;;
+        --apply-to-staged )
+            apply_to_staged=true
+            ;;
+        --cached | --staged )
+            staged=true
+            ;;
+        -i )
+            in_place=true
+            ;;
+        --style=* )
+            style="${arg//--style=/}"
+            ;;
+        --style )
+            [ $# -gt 0 ] || \
+                error_exit "No argument for --style option."
+            style="$1"
+            shift
+            ;;
+        --internal-opt-ignore-regex=* )
+            ignored+=("${arg//--internal-opt-ignore-regex=/}")
+            ;;
+        --internal-opt-ignore-regex )
+            ignored+=("${arg//--internal-opt-ignore-regex=/}")
+            [ $# -gt 0 ] || \
+                error_exit "No argument for --internal-opt-ignore-regex option."
+            ignored+=("$1")
+            shift
+            ;;
+        -- )
+            # Stop processing further arguments.
+            if [ $# -gt 0 ]; then
+                positionals+=("$@")
+                has_positionals=true
+            fi
+            break
+            ;;
+        -* )
+            error_exit "Unknown argument: $arg"
+            ;;
+        *)
+            positionals+=("$arg")
+            ;;
+    esac
+done
+
+# Restore positional arguments, access them from "$@".
+if [ ${#positionals[@]} -gt 0 ]; then
+    set -- "${positionals[@]}"
+    has_positionals=true
+fi
+
+[ -n "$style" ] || \
+    error_exit "If you use --style you need to specify a valid style."
+
+#######################################
+# Detection of clang-format & friends #
+#######################################
+
+# clang-format.
+declare format="${CLANG_FORMAT:-}"
+if [ -z "$format" ]; then
+    format=$(type -p clang-format)
+fi
+
+if [ -z "$format" ]; then
+    error_exit \
+        $'You need to install clang-format.\n' \
+        $'\n' \
+        $'On Ubuntu/Debian this is available in the clang-format package or, in\n' \
+        $'older distro versions, clang-format-VERSION.\n' \
+        $'On Fedora it\'s available in the clang package.\n' \
+        $'You can also specify your own path for clang-format by setting the\n' \
+        $'$CLANG_FORMAT environment variable.'
+fi
+
+# clang-format-diff.
+if [ "$whole_file" = false ]; then
+    invalid="/dev/null/invalid/path"
+    if [ "${OSTYPE:-}" = "linux-gnu" ]; then
+        readonly sort_version=-V
+    else
+        # On macOS, sort doesn't have -V.
+        readonly sort_version=-n
+    fi
+    declare paths_to_try=()
+    # .deb packages directly from upstream.
+    # We try these first as they are probably newer than the system ones.
+    while read -r f; do
+        paths_to_try+=("$f")
+    done < <(compgen -G "/usr/share/clang/clang-format-*/clang-format-diff.py" | sort "$sort_version" -r)
+    # LLVM official releases (just untarred in /usr/local).
+    while read -r f; do
+        paths_to_try+=("$f")
+    done < <(compgen -G "/usr/local/clang+llvm*/share/clang/clang-format-diff.py" | sort "$sort_version" -r)
+    # Maybe it's in the $PATH already? This is true for Ubuntu and Debian.
+    paths_to_try+=( \
+        "$(type -p clang-format-diff 2> /dev/null || echo "$invalid")" \
+        "$(type -p clang-format-diff.py 2> /dev/null || echo "$invalid")" \
+        )
+    # Fedora.
+    paths_to_try+=( \
+        /usr/share/clang/clang-format-diff.py \
+        )
+    # Gentoo.
+    while read -r f; do
+        paths_to_try+=("$f")
+    done < <(compgen -G "/usr/lib/llvm/*/share/clang/clang-format-diff.py" | sort -n -r)
+    # Homebrew.
+    while read -r f; do
+        paths_to_try+=("$f")
+    done < <(compgen -G "/usr/local/Cellar/clang-format/*/share/clang/clang-format-diff.py" | sort -n -r)
+
+    declare format_diff=
+
+    # Did the user specify a path?
+    if [ -n "${CLANG_FORMAT_DIFF:-}" ]; then
+        format_diff="$CLANG_FORMAT_DIFF"
+    else
+        for path in "${paths_to_try[@]}"; do
+            if [ -e "$path" ]; then
+                # Found!
+                format_diff="$path"
+                if [ ! -x "$format_diff" ]; then
+                    format_diff="python $format_diff"
+                fi
+                break
+            fi
+        done
+    fi
+
+    if [ -z "$format_diff" ]; then
+        error_exit \
+            $'Cannot find clang-format-diff which should be shipped as part of the same\n' \
+            $'package where clang-format is.\n' \
+            $'\n' \
+            $'Please find out where clang-format-diff is in your distro and report an issue\n' \
+            $'at https://github.com/barisione/clang-format-hooks/issues with details about\n' \
+            $'your operating system and setup.\n' \
+            $'\n' \
+            $'You can also specify your own path for clang-format-diff by setting the\n' \
+            $'$CLANG_FORMAT_DIFF environment variable, for instance:\n' \
+            $'\n' \
+            $'    CLANG_FORMAT_DIFF="python /.../clang-format-diff.py" \\\n' \
+            $'        ' "$bash_source"
+    fi
+
+    readonly format_diff
+fi
+
+
+############################
+# Actually run the command #
+############################
+
+if [ "$whole_file" = true ]; then
+
+    [ "$has_positionals" = true ] || \
+        error_exit "No files to reformat specified."
+    [ "$staged" = false ] || \
+        error_exit "--staged/--cached only make sense when applying to a diff."
+
+    read -r -a format_args <<< "$format"
+    format_args+=("-style=file")
+    [ "$in_place" = true ] && format_args+=("-i")
+
+    "${format_args[@]}" "$@"
+
+else # Diff-only.
+
+    if [ "$apply_to_staged" = true ]; then
+        [ "$staged" = false ] || \
+            error_exit "You don't need --staged/--cached with --apply-to-staged."
+        [ "$in_place" = false ] || \
+            error_exit "You don't need -i with --apply-to-staged."
+        staged=true
+        readonly patch_dest=$(mktemp)
+        trap '{ rm -f "$patch_dest"; }' EXIT
+    else
+        readonly patch_dest=/dev/stdout
+    fi
+
+    declare git_args=(git diff -U0 --no-color)
+    [ "$staged" = true ] && git_args+=("--staged")
+
+    # $format_diff may contain a command ("python") and the script to excute, so we
+    # need to split it.
+    read -r -a format_diff_args <<< "$format_diff"
+    [ "$in_place" = true ] && format_diff_args+=("-i")
+
+    # Build the regex for paths to consider or ignore.
+    # We use negative lookahead assertions which preceed the list of allowed patterns
+    # (that is, the extensions we want).
+    exclusions_regex=
+    if [ "${#ignored[@]}" -gt 0 ]; then
+        for pattern in "${ignored[@]}"; do
+            exclusions_regex="$exclusions_regex(?!$pattern)"
+        done
+    fi
+
+    "${git_args[@]}" "$@" \
+        | "${format_diff_args[@]}" \
+            -p1 \
+            -style="$style" \
+            -iregex="$exclusions_regex"'.*\.(c|cpp|cxx|cc|h|hpp|m|mm|js|java)' \
+            > "$patch_dest" \
+        || exit 1
+
+    if [ "$apply_to_staged" = true ]; then
+        if [ ! -s "$patch_dest" ]; then
+            echo "No formatting changes to apply."
+            exit 0
+        fi
+        patch -p0 < "$patch_dest" || \
+            error_exit "Cannot apply fix to local files."
+        git apply -p0 --cached < "$patch_dest" || \
+            error_exit "Cannot apply fix to git staged changes."
+    fi
+
+fi

openMZ/scripts/git-pre-commit-format

+#! /bin/bash
+#
+# Copyright 2018 Undo Ltd.
+#
+# https://github.com/barisione/clang-format-hooks
+
+# Force variable declaration before access.
+set -u
+# Make any failure in piped commands be reflected in the exit code.
+set -o pipefail
+
+readonly bash_source="${BASH_SOURCE[0]:-$0}"
+
+if [ -t 1 ] && hash tput 2> /dev/null; then
+    readonly b=$(tput bold)
+    readonly i=$(tput sitm)
+    readonly n=$(tput sgr0)
+else
+    readonly b=
+    readonly i=
+    readonly n=
+fi
+
+function error_exit() {
+    for str in "$@"; do
+        echo -n "$b$str$n" >&2
+    done
+    echo >&2
+
+    exit 1
+}
+
+# realpath is not available everywhere.
+function realpath() {
+    if [ "${OSTYPE:-}" = "linux-gnu" ]; then
+        readlink -m "$@"
+    else
+        # Python should always be available on macOS.
+        # We use sys.stdout.write instead of print so it's compatible with both Python 2 and 3.
+        python -c "import sys; import os.path; sys.stdout.write(os.path.realpath('''$1''') + '\\n')"
+    fi
+}
+
+# realpath --relative-to is only available on recent Linux distros.
+# This function behaves identical to Python's os.path.relpath() and doesn't need files to exist.
+function rel_realpath() {
+    local -r path=$(realpath "$1")
+    local -r rel_to=$(realpath "${2:-$PWD}")
+
+    # Split the paths into components.
+    IFS='/' read -r -a path_parts <<< "$path"
+    IFS='/' read -r -a rel_to_parts <<< "$rel_to"
+
+    # Search for the first different component.
+    for ((idx=1; idx<${#path_parts[@]}; idx++)); do
+        if [ "${path_parts[idx]}" != "${rel_to_parts[idx]:-}" ]; then
+            break
+        fi
+    done
+
+    result=()
+    # Add the required ".." to the $result array.
+    local -r first_different_idx="$idx"
+    for ((idx=first_different_idx; idx<${#rel_to_parts[@]}; idx++)); do
+        result+=("..")
+    done
+    # Add the required components from $path.
+    for ((idx=first_different_idx; idx<${#path_parts[@]}; idx++)); do
+        result+=("${path_parts[idx]}")
+    done
+
+    if [ "${#result[@]}" -gt 0 ]; then
+        # Join the array with a "/" as separator.
+        echo "$(export IFS='/'; echo "${result[*]}")"
+    else
+        echo .
+    fi
+}
+
+# Find the top-level git directory (taking into account we could be in a submodule).
+declare git_test_dir=.
+declare top_dir
+
+while true; do
+    top_dir=$(git -C "$git_test_dir" rev-parse --show-toplevel) || \
+        error_exit "You need to be in the git repository to run this script."
+
+    # Try to handle git worktree.
+    # The best way to deal both with git submodules and worktrees would be to
+    # use --show-superproject-working-tree, but it's not supported in git 2.7.4
+    # which is shipped in Ubuntu 16.04.
+    declare git_common_dir
+    if git_common_dir=$(git -C "$git_test_dir" rev-parse --git-common-dir 2>/dev/null); then
+        # The common dir could be relative, so we make it absolute.
+        git_common_dir=$(cd "$git_test_dir" && realpath "$git_common_dir")
+        declare maybe_top_dir
+        maybe_top_dir=$(realpath "$git_common_dir/..")
+        if [ -e "$maybe_top_dir/.git" ]; then
+            # We are not in a submodules, otherwise common dir would have been
+            # something like PROJ/.git/modules/SUBMODULE and there would not be
+            # a .git directory in PROJ/.git/modules/.
+            top_dir="$maybe_top_dir"
+        fi
+    fi
+
+    [ -e "$top_dir/.git" ] || \
+        error_exit "No .git directory in $top_dir."
+
+    if [ -d "$top_dir/.git" ]; then
+        # We are done! top_dir is the root git directory.
+        break
+    elif [ -f "$top_dir/.git" ]; then
+        # We are in a submodule.
+        git_test_dir="$git_test_dir/.."
+    fi
+done
+
+readonly top_dir
+
+hook_path="$top_dir/.git/hooks/pre-commit"
+readonly hook_path
+
+me=$(realpath "$bash_source") || exit 1
+readonly me
+
+me_relative_to_hook=$(rel_realpath "$me" "$(dirname "$hook_path")") || exit 1
+readonly me_relative_to_hook
+
+my_dir=$(dirname "$me") || exit 1
+readonly my_dir
+
+apply_format="$my_dir/apply-format"
+readonly apply_format
+
+apply_format_relative_to_top_dir=$(rel_realpath "$apply_format" "$top_dir") || exit 1
+readonly apply_format_relative_to_top_dir
+
+function is_installed() {
+    if [ ! -e "$hook_path" ]; then
+        echo nothing
+    else
+        existing_hook_target=$(realpath "$hook_path") || exit 1
+        readonly existing_hook_target
+
+        if [ "$existing_hook_target" = "$me" ]; then
+            # Already installed.
+            echo installed
+        else
+            # There's a hook, but it's not us.
+            echo different
+        fi
+    fi
+}
+
+function install() {
+    if ln -s "$me_relative_to_hook" "$hook_path" 2> /dev/null; then
+        echo "Pre-commit hook installed."
+    else
+        local -r res=$(is_installed)
+        if [ "$res" = installed ]; then
+            error_exit "The hook is already installed."
+        elif [ "$res" = different ]; then
+            error_exit "There's already an existing pre-commit hook, but for something else."
+        elif [ "$res" = nothing ]; then
+            error_exit "There's no pre-commit hook, but we couldn't create a symlink."
+        else
+            error_exit "Unexpected failure."
+        fi
+    fi
+}
+
+function uninstall() {
+    local -r res=$(is_installed)
+    if [ "$res" = installed ]; then
+        rm "$hook_path" || \
+            error_exit "Couldn't remove the pre-commit hook."
+    elif [ "$res" = different ]; then
+        error_exit "There's a pre-commit hook installed, but for something else. Not removing."
+    elif [ "$res" = nothing ]; then
+        error_exit "There's no pre-commit hook, nothing to uninstall."
+    else
+        error_exit "Unexpected failure detecting the pre-commit hook status."
+    fi
+}
+
+function show_help() {
+    cat << EOF
+${b}SYNOPSIS${n}
+
+    $bash_source [install|uninstall]
+
+${b}DESCRIPTION${n}
+
+    Git hook to verify and fix formatting before committing.
+
+    The script is invoked automatically when you commit, so you need to call it
+    directly only to set up the hook or remove it.
+
+    To setup the hook run this script passing "install" on the command line.
+    To remove the hook run passing "uninstall".
+
+${b}CONFIGURATION${n}
+
+    You can configure the hook using the "git config" command.
+
+    ${b}hooks.clangFormatDiffInteractive${n} (default: true)
+        By default, the hook requires user input. If you don't run git from a
+        terminal, you can disable the interactive prompt with:
+            ${i}\$ git config hooks.clangFormatDiffInteractive false${n}
+
+    ${b}hooks.clangFormatDiffStyle${n} (default: file)
+        Unless a different style is specified, the hook expects a file named
+        .clang-format to exist in the repository. This file should contain the
+        configuration for clang-format.
+        You can specify a different style (in this example, the WebKit one)
+        with:
+            ${i}\$ git config hooks.clangFormatDiffStyle WebKit${n}
+EOF
+}
+
+if [ $# = 1 ]; then
+    case "$1" in
+        -h | -\? | --help )
+            show_help
+            exit 0
+            ;;
+        install )
+            install
+            exit 0
+            ;;
+        uninstall )
+            uninstall
+            exit 0
+            ;;
+    esac
+fi
+
+[ $# = 0 ] || error_exit "Invalid arguments: $*"
+
+
+# This is a real run of the hook, not a install/uninstall run.
+
+if [ -z "${GIT_DIR:-}" ] && [ -z "${GIT_INDEX_FILE:-}" ]; then
+    error_exit \
+        $'It looks like you invoked this script directly, but it\'s supposed to be used\n' \
+        $'as a pre-commit git hook.\n' \
+        $'\n' \
+        $'To install the hook try:\n' \
+        $'    ' "$bash_source" $' install\n' \
+        $'\n' \
+        $'For more details on this script try:\n' \
+        $'    ' "$bash_source" $' --help\n'
+fi
+
+[ -x "$apply_format" ] || \
+    error_exit \
+    $'Cannot find the apply-format script.\n' \
+    $'I expected it here:\n' \
+    $'    ' "$apply_format"
+
+readonly style=$(cd "$top_dir" && git config hooks.clangFormatDiffStyle || echo file)
+
+apply_format_opts=(
+    "--style=$style"
+    --cached
+    )
+
+readonly exclusions_file="$top_dir/.clang-format-hook-exclude"
+if [ -e "$exclusions_file" ]; then
+    while IFS= read -r line; do
+        if [[ "$line" && "$line" != "#"* ]]; then
+            apply_format_opts+=("--internal-opt-ignore-regex=$line")
+        fi
+    done < "$exclusions_file"
+fi
+
+readonly patch=$(mktemp)
+trap '{ rm -f "$patch"; }' EXIT
+"$apply_format" --style="$style" --cached "${apply_format_opts[@]}" > "$patch" || \
+    error_exit $'\nThe apply-format script failed.'
+
+if [ "$(wc -l < "$patch")" -eq 0 ]; then
+    echo "The staged content is formatted correctly."
+    exit 0
+fi
+
+
+# The code is not formatted correctly.
+
+interactive=$(cd "$top_dir" && git config --bool hooks.clangFormatDiffInteractive)
+if [ "$interactive" != false ]; then
+    # Interactive is the default, so anything that is not false is converted to
+    # true, including possibly invalid values.
+    interactive=true
+fi
+readonly interactive
+
+if [ "$interactive" = false ]; then
+    echo "${b}The staged content is not formatted correctly.${n}"
+    echo "You can fix the formatting with:"
+    echo "    ${i}\$ ./$apply_format_relative_to_top_dir --apply-to-staged${n}"
+    echo
+    echo "You can also make this script interactive (if you use git from a terminal) with:"
+    echo "    ${i}\$ git config hooks.clangFormatDiffInteractive true${n}"
+    exit 1
+fi
+
+if hash colordiff 2> /dev/null; then
+    colordiff < "$patch"
+else
+    echo "${b}(Install colordiff to see this diff in color!)${n}"
+    echo
+    cat "$patch"
+fi
+
+# We don't want to suggest applying clang-format after merge resolution
+if git rev-parse MERGE_HEAD >/dev/null 2>&1; then
+    readonly this_is_a_merge=true
+else
+    readonly this_is_a_merge=false
+fi
+
+echo
+echo "${b}The staged content is not formatted correctly.${n}"
+echo "The fix shown above can be applied automatically to the commit."
+echo
+
+if $this_is_a_merge; then
+    echo "${b}You appear to be committing the result of a merge. It is not${n}"
+    echo "${b}recommended to apply the fix if it will reformat any code you${n}"
+    echo "${b}did not modify in your branch.${n}"
+    echo
+    readonly recommend_apply=" (not recommended for merge!)"
+    readonly recommend_force=""
+    readonly bold_apply=""
+    readonly bold_force="${b}"
+else
+    readonly recommend_apply=""
+    readonly recommend_force=" (not recommended!)"
+    readonly bold_apply="${b}"
+    readonly bold_force=""
+fi
+
+echo "You can:"
+echo " ${bold_apply}[a]: Apply the fix${recommend_apply}${n}"
+echo " ${bold_force}[f]: Force and commit anyway${recommend_force}${n}"
+echo " [c]: Cancel the commit"
+echo " [?]: Show help"
+echo
+
+readonly tty=${PRE_COMMIT_HOOK_TTY:-/dev/tty}
+
+while true; do
+    echo -n "What would you like to do? [a/f/c/?] "
+    read -r answer < "$tty"
+    case "$answer" in
+
+        [aA] )
+            patch -p0 < "$patch" || \
+                error_exit \
+                $'\n' \
+                $'Cannot apply fix to local files.\n' \
+                $'Have you modified the file locally after starting the commit?'
+            git apply -p0 --cached < "$patch" || \
+                error_exit \
+                $'\n' \
+                $'Cannot apply fix to git staged changes.\n' \
+                $'This may happen if you have some overlapping unstaged changes. To solve\n' \
+                $'you need to stage or reset changes manually.'
+
+            if $this_is_a_merge; then
+                echo
+                echo "Applied the fix to reformat the merge commit."
+                echo "You can always abort by quitting your editor with no commit message."
+                echo
+                echo -n "Press return to continue."
+                read -r < "$tty"
+            fi
+            ;;
+
+        [fF] )
+            echo
+            if ! $this_is_a_merge; then
+                echo "Will commit anyway!"
+                echo "You can always abort by quitting your editor with no commit message."
+                echo
+                echo -n "Press return to continue."
+                read -r < "$tty"
+            fi
+            exit 0
+            ;;
+
+        [cC] )
+            error_exit "Commit aborted as requested."
+            ;;
+
+        \? )
+            echo
+            show_help
+            echo
+            continue
+            ;;
+
+        * )
+            echo 'Invalid answer. Type "a", "f" or "c".'
+            echo
+            continue
+
+    esac
+    break
+done

openMZ/src/openmz/Makefile

+#  
+# Copyright 2020, Saab AB
+#  
+# This software may be distributed and modified according to
+# the terms of the MIT License.
+# Note that NO WARRANTY is provided.
+# See "LICENSE.MIT" for details.
+#  
+
+INCLUDES = include $(BSP_DIR)
+
+SOURCES = $(wildcard *.c *.S)
+HEADERS = $(wildcard *.h $(addsuffix /*.h, $(INCLUDES)))
+
+#CC = ccomp
+#CFLAGS = -finline-asm -fno-fpu -g
+
+CFLAGS = -march=$(ARCH) -mabi=$(ABI) -mcmodel=$(CMODEL)
+CFLAGS += -g -O2
+
+CFLAGS += $(addprefix -I, $(INCLUDES)) -nostdlib -static
+CFLAGS += -T $(BSP_DIR)/memory.lds -T default.lds
+
+.PHONY: compile 
+compile: $(PROGRAM_ELF)
+
+$(PROGRAM_ELF): $(SOURCES) $(HEADERS)
+	$(CC) $(CFLAGS) -o $@ $(SOURCES) 
+	$(SIZE) $@

openMZ/src/openmz/default.lds

+/**
+ * Copyright 2020, Saab AB
+ *
+ * This software may be distributed and modified according to 
+ * the terms of the GNU General Public License version 2. 
+ * Note that NO WARRANTY is provided.
+ * See "LICENSE.GPLv2" for details.
+ */
+OUTPUT_ARCH("riscv")
+
+ENTRY(_start)
+
+MEMORY
+{
+        /* 64 KiB rom */
+        rom (rxai!w) : ORIGIN = rom + 0x10000, LENGTH = 0x2000
+        itim (wx!rai) : ORIGIN = itim, LENGTH = 0x2000
+        /* 4 KiB ram */
+        ram (wxa!ri) : ORIGIN = ram, LENGTH = 0x1000 
+}
+
+SECTIONS
+{
+        /* 1 KiB stack */
+        __stack_size = DEFINED(__stack_size) ? __stack_size : 0x200;
+        PROVIDE(__stack_size = __stack_size);
+
+        .text : {
+                KEEP(*(.text.init))
+                . = ALIGN(8); 
+        } >rom AT>rom
+
+        .data : ALIGN(8) {
+                *(.data)
+                *(.data.*)
+                *(.sdata)
+                *(.sdata.*)
+                *(.rodata .rodata.*)
+                *(.rdata .rdata.*)
+                . = ALIGN(8); 
+        } >ram AT>rom
+
+        PROVIDE(__global_pointer$ = ADDR(.data)); 
+        PROVIDE(_data_lma = LOADADDR(.data)); 
+        PROVIDE(_data = ADDR(.data)); 
+        PROVIDE(_edata = ADDR(.data) + SIZEOF(.data)); 
+        
+        .itim : ALIGN(8) {
+                *(.text)
+                *(.text.*)
+        		*(.itim .itim.*)
+                . = ALIGN(8); 
+        } >ram AT>rom
+        
+        PROVIDE(_itim_lma = LOADADDR(.itim));
+        PROVIDE(_itim = ADDR(.itim));
+        PROVIDE(_eitim = ADDR(.itim) + SIZEOF(.itim));
+
+        .bss : ALIGN(8) {
+                *(.bss)
+                *(.bss.*)
+                *(.sbss*)
+                *(COMMON)
+                . = ALIGN(8); 
+        } >ram AT>ram
+        PROVIDE(_bss = ADDR(.bss)); 
+        PROVIDE(_ebss = ADDR(.bss) + SIZEOF(.bss)); 
+        PROVIDE(_heap = _ebss); 
+
+        .stack ORIGIN(ram) + LENGTH(ram) - __stack_size : {
+            . += __stack_size;
+        } >ram AT>ram
+        PROVIDE(_eheap = ADDR(.stack));
+        PROVIDE(_sp = ADDR(.stack) + SIZEOF(.stack));
+}

openMZ/src/openmz/ecall.c

+/**
+ * Copyright 2020, Saab AB
+ *
+ * This software may be distributed and modified according to
+ * the terms of the GNU General Public License version 2.
+ * Note that NO WARRANTY is provided.
+ * See "LICENSE.GPLv2" for details.
+ */
+
+#include "machine.h"
+#include "sched.h"
+
+#include "const.h"
+#include "csr.h"
+#include "kernel.h"
+#include "macro.h"
+#include "traps.h"
+
+/* handler takes a caller and its argument registers a0-a7 */
+typedef void (*handler_t)(zone_t* caller, uintptr_t args[8]);
+
+/* ECALL numbers */
+#define ECALL_YIELD 0
+#define ECALL_WFI 1
+#define ECALL_SEND 2
+#define ECALL_RECV 3
+#define ECALL_TRP_VECT 4
+#define ECALL_IRQ_VECT 5
+#define ECALL_CSRS_MIE 6
+#define ECALL_CSRC_MIE 7
+#define ECALL_CSRW_MTIMECMP 8
+#define ECALL_CSRR_MTIME 9
+#define ECALL_CSRR_MCYCLE 10
+#define ECALL_CSRR_MINSTR 11
+#define ECALL_CSRR_MHPMC3 12
+#define ECALL_CSRR_MHPMC4 13
+#define ECALL_CSRR_MISA 14
+#define ECALL_CSRR_MVENDID 15
+#define ECALL_CSRR_MARCHID 16
+#define ECALL_CSRR_MIMPID 17
+#define ECALL_CSRR_MHARTID 18
+
+void ecall_yield(zone_t* caller, uintptr_t args[8])
+{
+    KERNEL.deadline = read_mtime();
+    sched_yield();
+}
+
+static void ecall_send(zone_t* caller, uintptr_t args[8])
+{
+    uintptr_t receiver = args[0] - 1;
+    args[0] = 0;
+    if (receiver >= N_ZONES)
+        return;
+    inbox_t* inbox = &INBOXES[receiver][caller->id - 1];
+    if (inbox->full)
+        return;
+    inbox->full = 1;
+    for (int i = 0; i < N_MSGS; ++i)
+        inbox->msgs[i] = args[1 + i];
+    args[0] = 1;
+}
+
+static void ecall_recv(zone_t* caller, uintptr_t args[8])
+{
+    uintptr_t sender = args[0] - 1;
+    args[0] = 0;
+    if (sender >= N_ZONES)
+        return;
+    inbox_t* inbox = &INBOXES[caller->id - 1][sender];
+    if (!inbox->full)
+        return;
+    inbox->full = 0;
+    for (int i = 0; i < N_MSGS; ++i)
+        args[i + 1] = inbox->msgs[i];
+    args[0] = 1;
+}
+
+static void ecall_trp_vect(zone_t* caller, uintptr_t args[8])
+{
+    uintptr_t code = args[0];
+    uintptr_t handler = args[1];
+    if (code >= N_TRAPS)
+        return;
+    caller->trap_handlers[code] = handler;
+    if (code == UMODE_SOFT_TIMER)
+        caller->deadline = 0;
+}
+
+static void ecall_irq_vect(zone_t* caller, uintptr_t args[8])
+{
+    uintptr_t code = args[0];
+    uintptr_t handler = args[1];
+    if ((code >= N_INTERRUPTS) || (INTRP_HANDLERS[code].zone != caller))
+        return;
+    INTRP_HANDLERS[code].handler = handler;
+    if (handler) {
+        caller->uie |= (1 << code);
+        if (caller->ustatus & USTATUS_IE) {
+            KERNEL.mie |= (1 << code);
+        }
+    } else {
+        caller->uie &= ~(1 << code);
+        if (caller->ustatus & USTATUS_IE) {
+            KERNEL.mie &= ~(1 << code);
+        }
+    }
+}
+
+static void ecall_csrs_mie(zone_t* caller, uintptr_t UNUSED(args[8]))
+{
+    caller->ustatus |= USTATUS_IE;
+    KERNEL.mie |= caller->uie;
+}
+
+static void ecall_csrc_mie(zone_t* caller, uintptr_t UNUSED(args[8]))
+{
+    caller->ustatus &= ~USTATUS_IE;
+    KERNEL.mie &= ~caller->uie;
+}
+
+static void ecall_csrw_mtimecmp(zone_t* caller, uintptr_t args[8])
+{
+    caller->deadline = *((uint64_t*)args);
+}
+
+static void ecall_csrr_mtime(zone_t* caller, uintptr_t args[8])
+{
+    *((uint64_t*)args) = read_mtime();
+}
+
+static void ecall_csrr_mcycle(zone_t* caller, uintptr_t args[8])
+{
+    CSRR_COUNTER(args[0], mcycle);
+}
+
+static void ecall_csrr_minstr(zone_t* caller, uintptr_t args[8])
+{
+    CSRR_COUNTER(args[0], minstret);
+}
+
+static void ecall_csrr_mhpmc3(zone_t* caller, uintptr_t args[8])
+{
+    CSRR_COUNTER(args[0], mhpmcounter3);
+}
+
+static void ecall_csrr_mhpmc4(zone_t* caller, uintptr_t args[8])
+{
+    CSRR_COUNTER(args[0], mhpmcounter4);
+}
+
+static void ecall_csrr_misa(zone_t* caller, uintptr_t args[8])
+{
+    CSRR64(args[0], misa);
+}
+
+static void ecall_csrr_mvendid(zone_t* caller, uintptr_t args[8])
+{
+    CSRR64(args[0], mvendorid);
+}
+
+static void ecall_csrr_marchid(zone_t* caller, uintptr_t args[8])
+{
+    CSRR64(args[0], marchid);
+}
+
+static void ecall_csrr_mimpid(zone_t* caller, uintptr_t args[8])
+{
+    CSRR64(args[0], mimpid);
+}
+
+static void ecall_csrr_mhartid(zone_t* caller, uintptr_t args[8])
+{
+    CSRR64(args[0], mhartid);
+}
+
+static const handler_t ecall_handlers[] = {
+    [ECALL_YIELD] = ecall_yield,
+    [ECALL_WFI] = ecall_yield,
+    [ECALL_SEND] = ecall_send,
+    [ECALL_RECV] = ecall_recv,
+    [ECALL_TRP_VECT] = ecall_trp_vect,
+    [ECALL_IRQ_VECT] = ecall_irq_vect,
+    [ECALL_CSRS_MIE] = ecall_csrs_mie,
+    [ECALL_CSRC_MIE] = ecall_csrc_mie,
+    [ECALL_CSRW_MTIMECMP] = ecall_csrw_mtimecmp,
+    [ECALL_CSRR_MTIME] = ecall_csrr_mtime,
+    [ECALL_CSRR_MCYCLE] = ecall_csrr_mcycle,
+    [ECALL_CSRR_MINSTR] = ecall_csrr_minstr,
+    [ECALL_CSRR_MHPMC3] = ecall_csrr_mhpmc3,
+    [ECALL_CSRR_MHPMC4] = ecall_csrr_mhpmc4,
+    [ECALL_CSRR_MISA] = ecall_csrr_misa,
+    [ECALL_CSRR_MVENDID] = ecall_csrr_mvendid,
+    [ECALL_CSRR_MARCHID] = ecall_csrr_marchid,
+    [ECALL_CSRR_MIMPID] = ecall_csrr_mimpid,
+    [ECALL_CSRR_MHARTID] = ecall_csrr_mhartid,
+};
+
+void handle_ecall(uintptr_t mcause, uintptr_t mtval)
+{
+    /* ecall table */
+
+    zone_t* caller = &CURRENT;
+    /* always advance PC! */
+    caller->regs[PC] += 4;
+    uintptr_t ecall = caller->regs[A7];
+    if (ecall < ARRAY_LEN(ecall_handlers))
+        ecall_handlers[ecall](caller, caller->regs + A0);
+}