Content originally posted in LPCWare by gregUR on Wed Oct 10 01:38:21 MST 2012
Hi
I can build a simple code by GCC for ARM, and I am trying to run it on MCB4300 with gdbserver and arm-none-eabi.gdb. The linker script and startup code are taken from CMSIS v3 (Device/ARM/ARMCM4/Source/GCC/startup_ARMCM4.S and Device/ARM/ARMCM4/Source/GCC/gcc_arm.ld) without modifications, but I also tried to modify flash and RAM addresses in .ld file.
It builds without problems with this command:
./arm-none-eabi-gcc -g -mthumb -mcpu=cortex-m4 -march=armv7e-m -T Device/ARM/ARMCM4/Source/GCC/gcc_arm.ld Device/ARM/ARMCM4/Source/GCC/startup_ARMCM4.S main.c -o out.elf
I have to ctrl+c because it never gets to the breakpoint. Instead, it goes to 0x1c000206, but breakpoint is at 0x200. What are memory addresses that should be put into linker script ? Should anything else be changed in CMSIS's .ld and .s files ?
Output of arm-none-eabi-gbd:
(gdb) target remote :2331
Remote debugging using :2331
0x00000000 in __isr_vector ()
(gdb) load
Loading section .text, size 0x50c lma 0x0
Loading section .ARM.exidx, size 0x8 lma 0x50c
Loading section .data, size 0x440 lma 0x514
Loading section .jcr, size 0x4 lma 0x954
Start address 0x17d, load size 2392
Transfer rate: 395 bytes/sec, 598 bytes/write.
(gdb) break main
Breakpoint 1 at 0x200: file main.c, line 37.
(gdb) c
Continuing.
^C
Program received signal SIGTRAP, Trace/breakpoint trap.
0x1c000206 in ?? ()
(gdb)
and from gdbserver:
SEGGER J-Link GDB Server V4.50i
JLinkARM.dll V4.50i (DLL compiled Jun 22 2012 19:00:36)
The server has been started with the following settings:
---Server related settings---
GDBInit file: none
Listening port: 2331
SWO thread listening port: 2332
Accept remote connection: yes
Logfile: off
Verify download: off
Init regs on start: on
Silent mode: off
Single run mode: off
---J-Link related settings---
J-Link script: none
Target interface: JTAG
Host interface: USB
Target endian: little
Target interface speed: 5kHz
Waiting for J-Link connection...
J-Link is connected.
Firmware: J-Link ARM V8 compiled Aug 1 2012 13:40:47
Hardware: V8.00
S/N: 158007019
OEM: IAR
Checking target voltage...
Listening on TCP/IP port 2331
Connecting to target...
J-Link found 2 JTAG devices, Total IRLen = 8
JTAG ID: 0x4BA00477 (Cortex-M4)
Connected to target
Waiting for GDB connection...Connected to 127.0.0.1
Reading all registers
Read 4 bytes @ address 0x00000000 (Data = 0x1000BEC8)
Downloading 1292 bytes @ address 0x00000000
Downloading 8 bytes @ address 0x0000050C
Downloading 1088 bytes @ address 0x00000514
Downloading 4 bytes @ address 0x00000954
Writing register (PC = 0x0000017d)
Read 4 bytes @ address 0x0000017C (Data = 0x4B01F810)
Read 2 bytes @ address 0x00000200 (Data = 0x4809)
Read 2 bytes @ address 0x00000200 (Data = 0x4809)
Read 2 bytes @ address 0x00000200 (Data = 0x4809)
Setting breakpoint @ address 0x00000200, Size = 2, BPHandle = 0x0001
Starting target CPU...
Debugger requested to halt target...
...Target halted (PC = 0x1C000206)
Reading all registers
Removing breakpoint @ address 0x00000200, Size = 2
Read 4 bytes @ address 0x1C000206 (Data = 0xE7FEE7FE)
main.c:
int globalVar = 0;
void SystemInit (void) {
#if 0
uint32_t SystemCoreClock = __IRC;
#ifdef __CODE_RED
// CodeRed startup code will modify VTOR register to match
// when code has been linked to run from.
// Check whether we are running from external flash
if (SCB->VTOR == 0x1C000000)
/*Enable Buffer for External Flash*/
LPC_EMC->STATICCONFIG0 |= 1<<19;
// Call clock initialisation code
CGU_Init();
#else
#if defined(CORE_M4) || defined(CORE_M3)
// Enable VTOR register to point to vector table
SCB->VTOR = getPC() & 0xFFF00000;
#endif
/*Enable Buffer for External Flash*/
LPC_EMC->STATICCONFIG0 |= 1<<19;
#endif
#endif
}
int main(void)
{
int i;
while(1)
globalVar++;
return 0;
}
startup_ARMCM4.S:
/* File: startup_ARMCM4.S
* Purpose: startup file for Cortex-M4 devices. Should use with
* GCC for ARM Embedded Processors
* Version: V1.3
* Date: 08 Feb 2012
*
* Copyright (c) 2012, ARM Limited
* All rights reserved.
*
* 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 ARM Limited 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 ARM LIMITED 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.
*/
.syntax unified
.arch armv7-m
.section .stack
.align 3
#ifdef __STACK_SIZE
.equ Stack_Size, __STACK_SIZE
#else
.equ Stack_Size, 0x400
#endif
.globl __StackTop
.globl __StackLimit
__StackLimit:
.space Stack_Size
.size __StackLimit, . - __StackLimit
__StackTop:
.size __StackTop, . - __StackTop
.section .heap
.align 3
#ifdef __HEAP_SIZE
.equ Heap_Size, __HEAP_SIZE
#else
.equ Heap_Size, 0xC00
#endif
.globl __HeapBase
.globl __HeapLimit
__HeapBase:
.if Heap_Size
.space Heap_Size
.endif
.size __HeapBase, . - __HeapBase
__HeapLimit:
.size __HeapLimit, . - __HeapLimit
.section .isr_vector
.align 2
.globl __isr_vector
__isr_vector:
.long __StackTop /* Top of Stack */
.long Reset_Handler /* Reset Handler */
.long NMI_Handler /* NMI Handler */
.long HardFault_Handler /* Hard Fault Handler */
.long MemManage_Handler /* MPU Fault Handler */
.long BusFault_Handler /* Bus Fault Handler */
.long UsageFault_Handler /* Usage Fault Handler */
.long 0 /* Reserved */
.long 0 /* Reserved */
.long 0 /* Reserved */
.long 0 /* Reserved */
.long SVC_Handler /* SVCall Handler */
.long DebugMon_Handler /* Debug Monitor Handler */
.long 0 /* Reserved */
.long PendSV_Handler /* PendSV Handler */
.long SysTick_Handler /* SysTick Handler */
/* External interrupts */
.long WDT_IRQHandler /* 0: Watchdog Timer */
.long RTC_IRQHandler /* 1: Real Time Clock */
.long TIM0_IRQHandler /* 2: Timer0 / Timer1 */
.long TIM2_IRQHandler /* 3: Timer2 / Timer3 */
.long MCIA_IRQHandler /* 4: MCIa */
.long MCIB_IRQHandler /* 5: MCIb */
.long UART0_IRQHandler /* 6: UART0 - DUT FPGA */
.long UART1_IRQHandler /* 7: UART1 - DUT FPGA */
.long UART2_IRQHandler /* 8: UART2 - DUT FPGA */
.long UART4_IRQHandler /* 9: UART4 - not connected */
.long AACI_IRQHandler /* 10: AACI / AC97 */
.long CLCD_IRQHandler /* 11: CLCD Combined Interrupt */
.long ENET_IRQHandler /* 12: Ethernet */
.long USBDC_IRQHandler /* 13: USB Device */
.long USBHC_IRQHandler /* 14: USB Host Controller */
.long CHLCD_IRQHandler /* 15: Character LCD */
.long FLEXRAY_IRQHandler /* 16: Flexray */
.long CAN_IRQHandler /* 17: CAN */
.long LIN_IRQHandler /* 18: LIN */
.long I2C_IRQHandler /* 19: I2C ADC/DAC */
.long 0 /* 20: Reserved */
.long 0 /* 21: Reserved */
.long 0 /* 22: Reserved */
.long 0 /* 23: Reserved */
.long 0 /* 24: Reserved */
.long 0 /* 25: Reserved */
.long 0 /* 26: Reserved */
.long 0 /* 27: Reserved */
.long CPU_CLCD_IRQHandler /* 28: Reserved - CPU FPGA CLCD */
.long 0 /* 29: Reserved - CPU FPGA */
.long UART3_IRQHandler /* 30: UART3 - CPU FPGA */
.long SPI_IRQHandler /* 31: SPI Touchscreen - CPU FPGA */
.size __isr_vector, . - __isr_vector
.text
.thumb
.thumb_func
.align 2
.globl Reset_Handler
.type Reset_Handler, %function
Reset_Handler:
/* Loop to copy data from read only memory to RAM. The ranges
* of copy from/to are specified by following symbols evaluated in
* linker script.
* __etext: End of code section, i.e., begin of data sections to copy from.
* __data_start__/__data_end__: RAM address range that data should be
* copied to. Both must be aligned to 4 bytes boundary. */
ldr r1, =__etext
ldr r2, =__data_start__
ldr r3, =__data_end__
#if 1
/* Here are two copies of loop implemenations. First one favors code size
* and the second one favors performance. Default uses the first one.
* Change to "#if 0" to use the second one */
.flash_to_ram_loop:
cmp r2, r3
ittt lt
ldrlt r0, [r1], #4
strlt r0, [r2], #4
blt .flash_to_ram_loop
#else
subs r3, r2
ble .flash_to_ram_loop_end
.flash_to_ram_loop:
subs r3, #4
ldr r0, [r1, r3]
str r0, [r2, r3]
bgt .flash_to_ram_loop
.flash_to_ram_loop_end:
#endif
#ifndef __NO_SYSTEM_INIT
ldr r0, =SystemInit
blx r0
#endif
ldr r0, =_start
bx r0
.pool
.size Reset_Handler, . - Reset_Handler
/* Macro to define default handlers. Default handler
* will be weak symbol and just dead loops. They can be
* overwritten by other handlers */
.macro def_irq_handler handler_name
.align 1
.thumb_func
.weak \handler_name
.type \handler_name, %function
\handler_name :
b .
.size \handler_name, . - \handler_name
.endm
def_irq_handler NMI_Handler
def_irq_handler HardFault_Handler
def_irq_handler MemManage_Handler
def_irq_handler BusFault_Handler
def_irq_handler UsageFault_Handler
def_irq_handler SVC_Handler
def_irq_handler DebugMon_Handler
def_irq_handler PendSV_Handler
def_irq_handler SysTick_Handler
def_irq_handler Default_Handler
def_irq_handler WDT_IRQHandler
def_irq_handler RTC_IRQHandler
def_irq_handler TIM0_IRQHandler
def_irq_handler TIM2_IRQHandler
def_irq_handler MCIA_IRQHandler
def_irq_handler MCIB_IRQHandler
def_irq_handler UART0_IRQHandler
def_irq_handler UART1_IRQHandler
def_irq_handler UART2_IRQHandler
def_irq_handler UART3_IRQHandler
def_irq_handler UART4_IRQHandler
def_irq_handler AACI_IRQHandler
def_irq_handler CLCD_IRQHandler
def_irq_handler ENET_IRQHandler
def_irq_handler USBDC_IRQHandler
def_irq_handler USBHC_IRQHandler
def_irq_handler CHLCD_IRQHandler
def_irq_handler FLEXRAY_IRQHandler
def_irq_handler CAN_IRQHandler
def_irq_handler LIN_IRQHandler
def_irq_handler I2C_IRQHandler
def_irq_handler CPU_CLCD_IRQHandler
def_irq_handler SPI_IRQHandler
.end
gcc_arm.ld:
/* Linker script to configure memory regions. */
MEMORY
{
FLASH (rx) : ORIGIN = 0x00000000, LENGTH = 0x40000 /* 256k */
RAM (rwx) : ORIGIN = 0x20000000, LENGTH = 0x08000 /* 32k */
}
/* Library configurations */
GROUP(libgcc.a libc.a libm.a libnosys.a)
/* Linker script to place sections and symbol values. Should be used together
* with other linker script that defines memory regions FLASH and RAM.
* It references following symbols, which must be defined in code:
* Reset_Handler : Entry of reset handler
*
* It defines following symbols, which code can use without definition:
* __exidx_start
* __exidx_end
* __etext
* __data_start__
* __preinit_array_start
* __preinit_array_end
* __init_array_start
* __init_array_end
* __fini_array_start
* __fini_array_end
* __data_end__
* __bss_start__
* __bss_end__
* __end__
* end
* __HeapLimit
* __StackLimit
* __StackTop
* __stack
*/
ENTRY(Reset_Handler)
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*)
KEEP(*(.eh_frame*))
} > FLASH
.ARM.extab :
{
*(.ARM.extab* .gnu.linkonce.armextab.*)
} > FLASH
__exidx_start = .;
.ARM.exidx :
{
*(.ARM.exidx* .gnu.linkonce.armexidx.*)
} > FLASH
__exidx_end = .;
__etext = .;
.data : AT (__etext)
{
__data_start__ = .;
*(vtable)
*(.data*)
. = ALIGN(4);
/* preinit data */
PROVIDE_HIDDEN (__preinit_array_start = .);
KEEP(*(.preinit_array))
PROVIDE_HIDDEN (__preinit_array_end = .);
. = ALIGN(4);
/* init data */
PROVIDE_HIDDEN (__init_array_start = .);
KEEP(*(SORT(.init_array.*)))
KEEP(*(.init_array))
PROVIDE_HIDDEN (__init_array_end = .);
. = ALIGN(4);
/* finit data */
PROVIDE_HIDDEN (__fini_array_start = .);
KEEP(*(SORT(.fini_array.*)))
KEEP(*(.fini_array))
PROVIDE_HIDDEN (__fini_array_end = .);
. = ALIGN(4);
/* All data end */
__data_end__ = .;
} > RAM
.bss :
{
__bss_start__ = .;
*(.bss*)
*(COMMON)
__bss_end__ = .;
} > RAM
.heap :
{
__end__ = .;
end = __end__;
*(.heap*)
__HeapLimit = .;
} > RAM
/* .stack_dummy section doesn't contains any symbols. It is only
* used for linker to calculate size of stack sections, and assign
* values to stack symbols later */
.stack_dummy :
{
*(.stack)
} > RAM
/* Set stack top to end of RAM, and stack limit move down by
* size of stack_dummy section */
__StackTop = ORIGIN(RAM) + LENGTH(RAM);
__StackLimit = __StackTop - SIZEOF(.stack_dummy);
PROVIDE(__stack = __StackTop);
/* Check if data + heap + stack exceeds RAM limit */
ASSERT(__StackLimit >= __HeapLimit, "region RAM overflowed with stack")
}