view Small_CPU/CPU2-RTE.ld @ 232:f0069f002c55 div-fixes-4-1

Bugfix: make date/time setting work over reboots Setting the time/date over the UART interface or by the menu, seems to work, but a reboot of the RTE brings back strange, seemingly random, time. The reason for this is rather simple. In the settings, a time is stored, based on some flawed logic, and that time was restored on reboot. There is no reason to store any time, when the moment of restoring it is unrelated in time. So, the fix is simple: do not set time (in the RTC) based on some time from the past. The whole idea of a RTC is that it does preserve the time for you, as long its powered. Any attempt to do things better using stored time data is futile (and nonsense). And while working on his, also kick out some useless code from the RTE. There is no reason to initialize the time on the RTC to some random time/date in the past. A zero data/time is as good and any random date. Signed-off-by: Jan Mulder <jlmulder@xs4all.nl>
author Jan Mulder <jlmulder@xs4all.nl>
date Wed, 03 Apr 2019 21:11:56 +0200
parents 321df89d5710
children aa286a4926c2
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/* ---------------------------------------------------------------------------- */
/*                  Em::Blocks embedded development Support                     */
/* ---------------------------------------------------------------------------- */
/* Copyright (c) 2014, EmBlocks                                                 */
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/* ---------------------------------------------------------------------------- */

/*------------------------------------------------------------------------------
 *      Linker script for running in internal FLASH on the STM32F401RE
 *----------------------------------------------------------------------------*/

/* Entry Point */
ENTRY(Reset_Handler)

OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm")
OUTPUT_ARCH(arm)
SEARCH_DIR(.)

/* Memory Spaces Definitions */
MEMORY
{
    ROM  (rx) : ORIGIN = 0x08000000, LENGTH = 512K /* 80000 */
    RAM (rwx) : ORIGIN = 0x20000000, LENGTH = 96K
}
/* 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
 */


SECTIONS
{
  .isr_vector 0x08000000 :
  {
  . = ALIGN(4);
    KEEP( *(.isr_vector) ) 
    KEEP(*(.init))
    KEEP(*(.fini))
  } >ROM
  
	/* Place FirmwareData at absolute address */
	.firmware_data 0x08005000:
	{
		cpu2_FirmwareData = 0; 
		KEEP( *(.firmware_data) )
	} > ROM

	.text 0x08005100 :
	{	
		. = ALIGN(4);
		*(.text)           /* .text sections (code) */
		*(.text*)
		*(.eh_frame*)
        . = ALIGN(4); 
  
	} > ROM

/********************** Constant data into ROM memory *********************/
  .rodata :
  {
    . = ALIGN(4);
    *(.rodata)         /* .rodata sections (constants, strings, etc.) */
    *(.rodata*)        /* .rodata* sections (constants, strings, etc.) */
    . = ALIGN(4);
  } >ROM
  
	.ARM.extab :
	{
		*(.ARM.extab* .gnu.linkonce.armextab.*)
	} > ROM

	__exidx_start = .;
	.ARM.exidx :
	{
		*(.ARM.exidx* .gnu.linkonce.armexidx.*)
	} > ROM
	__exidx_end = .;

  .preinit_array     :
  {
    . = ALIGN(4);
    PROVIDE_HIDDEN( __preinit_array_start = . );
    KEEP( *(.preinit_array*) )
    PROVIDE_HIDDEN( __preinit_array_end = . );
    . = ALIGN(4);
  } >ROM
  
  .init_array :
  {
    . = ALIGN(4);
    PROVIDE_HIDDEN( __init_array_start = . );
    KEEP( *(SORT(.init_array.*)) )
    KEEP( *(.init_array*) )
    PROVIDE_HIDDEN( __init_array_end = . );
    . = ALIGN(4);
  } >ROM
  
  .fini_array :
  {
    . = ALIGN(4);
    PROVIDE_HIDDEN( __fini_array_start = . );
    KEEP( *(SORT(.fini_array.*)) )
    KEEP( *(.fini_array*) )
    PROVIDE_HIDDEN( __fini_array_end = . );
    . = ALIGN(4);
    
    __etext = .;        /* define a global symbols at end of code */
  } >ROM

 /* Used by the startup to initialize data */
 	_sidata = LOADADDR(.data);

	.data : 
	{
		. = ALIGN(4);
		__data_start__ = .;
		_sdata = .;        /* create a global symbol at data start */
    	*(.data)           /* .data sections */
		*(.data*)
		*(vtable)
		. = ALIGN(4);
		/* All data end */
		__data_end__ = .;
	} >RAM AT>ROM

	.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")
}