arch: k210: Fix stack coloring for the idle thread stack

Summary:
- I noticed that stack coloring for the idle thread stacks does
  not work due to the recent changes
- This commit fixes this issue

Impact:
- k210 only

Testing:
- Tested with both maix-bit (dev board) and QEMU

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

arch/risc-v/src/k210/Make.defs

@@ -29,7 +29,7 @@ CMN_ASRCS  += riscv_testset.S
 
 # Specify C code within the common directory to be included
 CMN_CSRCS  += riscv_initialize.c riscv_swint.c
-CMN_CSRCS  += riscv_allocateheap.c riscv_createstack.c riscv_exit.c riscv_fault.c
+CMN_CSRCS  += riscv_createstack.c riscv_exit.c riscv_fault.c
 CMN_CSRCS  += riscv_assert.c riscv_blocktask.c riscv_copystate.c riscv_initialstate.c
 CMN_CSRCS  += riscv_interruptcontext.c riscv_modifyreg32.c riscv_puts.c
 CMN_CSRCS  += riscv_releasepending.c riscv_reprioritizertr.c

arch/risc-v/src/k210/k210_allocateheap.c

@@ -30,6 +30,7 @@
 #include <nuttx/userspace.h>
 
 #include <nuttx/arch.h>
+#include <nuttx/board.h>
 #include <arch/board/board.h>
 
 #include "k210.h"
@@ -44,6 +45,28 @@
  * Public Functions
  ****************************************************************************/
 
+/****************************************************************************
+ * Name: up_allocate_heap
+ *
+ * Description:
+ *   This function will be called to dynamically set aside the heap region.
+ *
+ *   For the kernel build (CONFIG_BUILD_PROTECTED=y) with both kernel- and
+ *   user-space heaps (CONFIG_MM_KERNEL_HEAP=y), this function provides the
+ *   size of the unprotected, user-space heap.
+ *
+ *   If a protected kernel-space heap is provided, the kernel heap must be
+ *   allocated (and protected) by an analogous up_allocate_kheap().
+ *
+ ****************************************************************************/
+
+void up_allocate_heap(FAR void **heap_start, size_t *heap_size)
+{
+  board_autoled_on(LED_HEAPALLOCATE);
+  *heap_start = (FAR void *)K210_HEAP_START;
+  *heap_size = CONFIG_RAM_END - K210_HEAP_START;
+}
+
 /****************************************************************************
  * Name: up_allocate_kheap
  *

arch/risc-v/src/k210/k210_cpustart.c

@@ -112,6 +112,17 @@ void k210_cpu_boot(int cpu)
   showprogress('b');
   DPRINTF("CPU%d Started\n", this_cpu());
 
+#ifdef CONFIG_STACK_COLORATION
+  FAR struct tcb_s *tcb = this_task();
+
+  /* If stack debug is enabled, then fill the stack with a
+   * recognizable value that we can use later to test for high
+   * water marks.
+   */
+
+  riscv_stack_color(tcb->stack_alloc_ptr, tcb->adj_stack_size);
+#endif
+
   /* TODO: Setup FPU */
 
   /* Clear machine software interrupt for CPU(cpu) */

arch/risc-v/src/k210/k210_memorymap.h

@@ -51,9 +51,9 @@ extern uintptr_t *_default_stack_limit;
 #define K210_IDLESTACK1_TOP  (K210_IDLESTACK1_BASE + CONFIG_IDLETHREAD_STACKSIZE)
 
 #if defined(CONFIG_SMP) && (CONFIG_SMP_NCPUS > 1)
-#define K210_IDLESTACK_TOP   (K210_IDLESTACK1_TOP)
+#define K210_HEAP_START   (K210_IDLESTACK1_TOP)
 #else
-#define K210_IDLESTACK_TOP   (K210_IDLESTACK0_TOP)
+#define K210_HEAP_START   (K210_IDLESTACK0_TOP)
 #endif
 
 #endif /* _ARCH_RISCV_SRC_K210_K210_MEMORYMAP_H */

arch/risc-v/src/k210/k210_start.c

@@ -48,17 +48,11 @@
  * Public Data
  ****************************************************************************/
 
-/* g_idle_topstack: _sbss is the start of the BSS region as defined by the
- * linker script. _ebss lies at the end of the BSS region. The idle task
- * stack starts at the end of BSS and is of size CONFIG_IDLETHREAD_STACKSIZE.
- * The IDLE thread is the thread that the system boots on and, eventually,
- * becomes the IDLE, do nothing task that runs only when there is nothing
- * else to run.  The heap continues from there until the end of memory.
- * g_idle_topstack is a read-only variable the provides this computed
- * address.
+/* NOTE: g_idle_topstack needs to point the top of the idle stack
+ * for CPU0 and this value is used in up_initial_state()
  */
 
-uintptr_t g_idle_topstack = K210_IDLESTACK_TOP;
+uintptr_t g_idle_topstack = K210_IDLESTACK0_TOP;
 volatile bool g_serial_ok = false;
 
 extern void k210_cpu_boot(uint32_t);