fix heap memory error : start from _bss_end and conflict with stack segment

Ubiquitous/XiZi_IIoT/board/hc32f4a0/.defconfig

@@ -75,7 +75,7 @@ CONFIG_KERNEL_SEMAPHORE=y
 CONFIG_KERNEL_MUTEX=y
 CONFIG_KERNEL_EVENT=y
 CONFIG_KERNEL_MESSAGEQUEUE=y
-CONFIG_KERNEL_SOFTTIMER=n
+CONFIG_KERNEL_SOFTTIMER=y
 CONFIG_SCHED_POLICY_RR_REMAINSLICE=y
 # CONFIG_SCHED_POLICY_RR is not set
 # CONFIG_SCHED_POLICY_FIFO is not set
@@ -134,7 +134,7 @@ CONFIG_SHELL_HELP_LIST_VAR=y
 # Kernel data structure Manage
 #
 CONFIG_KERNEL_QUEUEMANAGE=y
-CONFIG_KERNEL_WORKQUEUE=n
+CONFIG_KERNEL_WORKQUEUE=y
 CONFIG_WORKQUEUE_KTASK_STACKSIZE=2048
 CONFIG_WORKQUEUE_KTASK_PRIORITY=23
 CONFIG_QUEUE_MAX=16

Ubiquitous/XiZi_IIoT/board/hc32f4a0/board.h

@@ -35,11 +35,11 @@ Modification:
 
 #include <stdint.h>
 
-extern int __bss_end;
+extern int __heap_start;
 extern unsigned int g_service_table_start;
 extern unsigned int g_service_table_end;
 
-#define MEMORY_START_ADDRESS    (&__bss_end)
+#define MEMORY_START_ADDRESS    (&__heap_start)
 #define HC32F4_SRAM_SIZE         512
 #define MEMORY_END_ADDRESS      (0x1FFE0000 + HC32F4_SRAM_SIZE * 1024)
 

Ubiquitous/XiZi_IIoT/board/hc32f4a0/link.lds

@@ -216,20 +216,18 @@ SECTIONS
         __end__ = .;
         PROVIDE(end = .);
         PROVIDE(_end = .);
-        *(.heap*)
-        . = ALIGN(8);
-        __HeapLimit = .;
 
         __StackLimit = .;
         *(.stack*)
         . = ALIGN(8);
         __StackTop = .;
+
+        __heap_start = .;
     } >RAM
 
     .ARM.attributes 0 : { *(.ARM.attributes) }
 
     PROVIDE(_stack = __StackTop);
-    PROVIDE(_Min_Heap_Size = __HeapLimit - __HeapBase);
     PROVIDE(_Min_Stack_Size = __StackTop - __StackLimit);
 
     __RamEnd = ORIGIN(RAM) + LENGTH(RAM);