baremetal: Add GCC toolchain support to pca10040 example

Change-Id: I7a482296ecbcddc91d6ab430155d6a45e32a2cc7
Reviewed-by: Ivan Komissarov <ABBAPOH@gmail.com>
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

4 files changed, 437 insertions, 1 deletions

diff --git a/examples/baremetal/pca10040/greenblink/README.md b/examples/baremetal/pca10040/greenblink/README.md
index 84c49fff1..8b08365f8 100644
--- a/examples/baremetal/pca10040/greenblink/README.md
+++ b/examples/baremetal/pca10040/greenblink/README.md
@@ -5,4 +5,5 @@ LED on the board.
 
 The following toolchains are supported:
 
+  * GNU Arm Embedded Toolchain
   * KEIL Microcontroller Development Kit
diff --git a/examples/baremetal/pca10040/greenblink/gcc/flash.ld b/examples/baremetal/pca10040/greenblink/gcc/flash.ld
new file mode 100644
index 000000000..b998618ae
--- /dev/null
+++ b/examples/baremetal/pca10040/greenblink/gcc/flash.ld
@@ -0,0 +1,151 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 Denis Shienkov <denis.shienkov@gmail.com>
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of Qbs.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+ENTRY(reset_handler)
+
+MEMORY
+{
+  FLASH (rx) : ORIGIN = 0x00000000, LENGTH = 0x80000
+  RAM (rwx) : ORIGIN = 0x20000000, LENGTH = 0x10000
+  CODE_RAM (rwx) : ORIGIN = 0x800000, LENGTH = 0x10000
+}
+
+SECTIONS {
+    .text : {
+        KEEP(*(.isr_vector))
+        *(.text*)
+        KEEP(*(.init))
+        KEEP(*(.fini))
+        /* .ctors */
+        *crtbegin.o(.ctors)
+        *crtbegin?.o(.ctors)
+        *(EXCLUDE_FILE(*crtend?.o *crtend.o) .ctors)
+        *(SORT(.ctors.*))
+        *(.ctors)
+        /* .dtors */
+         *crtbegin.o(.dtors)
+         *crtbegin?.o(.dtors)
+         *(EXCLUDE_FILE(*crtend?.o *crtend.o) .dtors)
+         *(SORT(.dtors.*))
+         *(.dtors)
+        *(.rodata*)
+        *(.eh_frame*)
+        . = ALIGN(4);
+    } > FLASH
+
+    .ARM.extab : {
+        *(.ARM.extab* .gnu.linkonce.armextab.*)
+        . = ALIGN(4);
+    } > FLASH
+
+    _start_of_exidx_section = .;
+    .ARM.exidx : {
+        *(.ARM.exidx* .gnu.linkonce.armexidx.*)
+        . = ALIGN(4);
+    } > FLASH
+    _end_of_exidx_section = .;
+
+    _end_of_code_section = .;
+
+    .data : AT (_end_of_code_section) {
+        _start_of_data_section = .;
+        *(vtable)
+        *(.data*)
+        . = ALIGN(4);
+        /* preinit data */
+        PROVIDE_HIDDEN(__preinit_array_start = .);
+        *(.preinit_array)
+        PROVIDE_HIDDEN(__preinit_array_end = .);
+        . = ALIGN(4);
+        /* init data */
+        PROVIDE_HIDDEN(__init_array_start = .);
+        *(SORT(.init_array.*))
+        *(.init_array)
+        PROVIDE_HIDDEN(__init_array_end = .);
+        . = ALIGN(4);
+        /* finit data */
+        PROVIDE_HIDDEN(__fini_array_start = .);
+        *(SORT(.fini_array.*))
+        *(.fini_array)
+        PROVIDE_HIDDEN(__fini_array_end = .);
+        *(.jcr)
+        . = ALIGN(4);
+        /* All data end */
+        _end_of_data_section = .;
+    } > RAM
+
+    .bss : {
+        . = ALIGN(4);
+        __bss_start__ = .;
+        *(.bss*)
+        *(COMMON)
+        . = ALIGN(4);
+        __bss_end__ = .;
+    } > RAM
+
+    .heap (COPY): {
+        __end__ = .;
+        end = __end__;
+        *(.heap*)
+        _heap_limit = .;
+    } > RAM
+
+    .stack_dummy (COPY): {
+        *(.stack*)
+    } > RAM
+
+    /* Set stack top to end of RAM, and stack limit move down by size of stack_dummy section. */
+    _end_of_stack = ORIGIN(RAM) + LENGTH(RAM);
+    _stack_limit = _end_of_stack - SIZEOF(.stack_dummy);
+    PROVIDE(__stack = _end_of_stack);
+
+    /* Check if data + heap + stack exceeds RAM limit */
+    ASSERT(_stack_limit >= _heap_limit, "region RAM overflowed with stack")
+}
diff --git a/examples/baremetal/pca10040/greenblink/gcc/startup.s b/examples/baremetal/pca10040/greenblink/gcc/startup.s
new file mode 100644
index 000000000..d1fe7e9de
--- /dev/null
+++ b/examples/baremetal/pca10040/greenblink/gcc/startup.s
@@ -0,0 +1,253 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 Denis Shienkov <denis.shienkov@gmail.com>
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of Qbs.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+.syntax unified
+.arch armv7e-m
+.thumb
+
+// Define the stack.
+.section .stack
+.align 3
+.equ    _size_of_stack, 8192
+.globl _end_of_stack
+.globl _stack_limit
+_stack_limit:
+.space _size_of_stack
+.size _stack_limit, . - _stack_limit
+_end_of_stack:
+.size _end_of_stack, . - _end_of_stack
+
+// Define the heap.
+.section .heap
+.align 3
+.equ _size_of_heap, 8192
+.globl _end_of_heap
+.globl _heap_limit
+_end_of_heap:
+.space _size_of_heap
+.size _end_of_heap, . - _end_of_heap
+_heap_limit:
+.size _heap_limit, . - _heap_limit
+
+// Define the empty vectors table.
+.section .isr_vector, "ax"
+.align 2
+.globl _vectors_table
+_vectors_table:
+    // Generic interrupts offset.
+    .word    _end_of_stack  // Initial stack pointer value.
+    .word    reset_handler  // Reset.
+    .word    0              // NMI.
+    .word    0              // Hard fault.
+    .word    0              // Memory management fault.
+    .word    0              // Bus fault.
+    .word    0              // Usage fault.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // SVC.
+    .word    0              // Debug monitor.
+    .word    0              // Reserved.
+    .word    0              // PendSV.
+    .word    0              // SysTick.
+
+    // External interrupts offset.
+    .word    0              // POWER CLOCK.
+    .word    0              // RADIO.
+    .word    0              // UARTE0/UART0
+    .word    0              // SPIM0/SPIS0/TWIM0/TWIS0/SPI0/TWI0.
+    .word    0              // SPIM1/SPIS1/TWIM1/TWIS1/SPI1/TWI1.
+    .word    0              // NFCT.
+    .word    0              // GPIOTE.
+    .word    0              // SAADC.
+    .word    0              // TIMER0.
+    .word    0              // TIMER1.
+    .word    0              // TIMER2.
+    .word    0              // RTC0.
+    .word    0              // TEMP.
+    .word    0              // RNG.
+    .word    0              // ECB.
+    .word    0              // CCM_AAR.
+    .word    0              // WDT.
+    .word    0              // RTC1.
+    .word    0              // QDEC.
+    .word    0              // COMP_LPCOMP.
+    .word    0              // SWI0_EGU0.
+    .word    0              // SWI1_EGU1.
+    .word    0              // SWI2_EGU2.
+    .word    0              // SWI3_EGU3.
+    .word    0              // SWI4_EGU4.
+    .word    0              // SWI5_EGU5.
+    .word    0              // TIMER3.
+    .word    0              // TIMER4.
+    .word    0              // PWM0.
+    .word    0              // PDM.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // MWU.
+    .word    0              // PWM1.
+    .word    0              // PWM2.
+    .word    0              // SPIM2/SPIS2/SPI2.
+    .word    0              // RTC2.
+    .word    0              // I2S.
+    .word    0              // FPU.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+    .word    0              // Reserved.
+.size _vectors_table, . - _vectors_table
+
+// Define the 'reset_handler' function, which is an entry point.
+.text
+.thumb
+.thumb_func
+.align 1
+.globl reset_handler
+.type reset_handler, %function
+reset_handler:
+    // Loop to copy data from read only memory to RAM.
+    ldr     r1, =_end_of_code_section
+    ldr     r2, =_start_of_data_section
+    ldr     r3, =__bss_start__
+    subs    r3, r3, r2
+    ble    _copy_data_init_done
+_copy_data_init:
+    subs    r3, r3, #4
+    ldr     r0, [r1,r3]
+    str     r0, [r2,r3]
+    bgt     _copy_data_init
+_copy_data_init_done:
+    // Zero fill the bss segment.
+    ldr     r1, =__bss_start__
+    ldr     r2, =__bss_end__
+    movs    r0, 0
+    subs    r2, r2, r1
+    ble     _loop_fill_zero_bss_done
+
+_loop_fill_zero_bss:
+    subs    r2, r2, #4
+    str     r0, [r1, r2]
+    bgt     _loop_fill_zero_bss
+
+_loop_fill_zero_bss_done:
+    // Call the application's entry point.
+    bl      main
+    bx      lr
+.size reset_handler, . - reset_handler
diff --git a/examples/baremetal/pca10040/greenblink/greenblink.qbs b/examples/baremetal/pca10040/greenblink/greenblink.qbs
index 8f1c7650c..04a592aee 100644
--- a/examples/baremetal/pca10040/greenblink/greenblink.qbs
+++ b/examples/baremetal/pca10040/greenblink/greenblink.qbs
@@ -54,13 +54,44 @@ CppApplication {
     condition: {
         if (!qbs.architecture.startsWith("arm"))
             return false;
-        return qbs.toolchain.contains("keil")
+        return qbs.toolchain.contains("gcc")
+            || qbs.toolchain.contains("keil")
     }
     name: "pca10040-greenblink"
     cpp.cLanguageVersion: "c99"
     cpp.positionIndependentCode: false
 
     //
+    // GCC-specific properties and sources.
+    //
+
+    Properties {
+        condition: qbs.toolchain.contains("gcc")
+        cpp.driverFlags: [
+            "-mcpu=cortex-m4",
+            "-mfloat-abi=hard",
+            "-mfpu=fpv4-sp-d16",
+            "-specs=nosys.specs"
+        ]
+    }
+
+    Group {
+        condition: qbs.toolchain.contains("gcc")
+        name: "GCC"
+        prefix: "gcc/"
+        Group {
+            name: "Startup"
+            fileTags: ["asm"]
+            files: ["startup.s"]
+        }
+        Group {
+            name: "Linker Script"
+            fileTags: ["linkerscript"]
+            files: ["flash.ld"]
+        }
+    }
+
+    //
     // KEIL-specific properties and sources.
     //