arch/xtensa/src/esp32/esp32_allocateheap.c: Fix the memory regions with

regards to the data used by the ROM.
Static alloaction sections should end at the begining of the ROM data.
The rest of memory (End of ROM data --> End of DRAM) is added to the
heap.

Signed-off-by: Abdelatif Guettouche <abdelatif.guettouche@espressif.com>

arch/xtensa/src/esp32/esp32_allocateheap.c

@@ -53,6 +53,26 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
+/* Region 1 of the heap is the area from the end of the .data section to the
+ * begining of the ROM data.  The start address is defined from the linker
+ * script as "_sheap".  Then end is defined here, as follows:
+ */
+
+#define HEAP_REGION1_END 0x3ffe0000
+
+/* Region 2 of the heap is the area from the end of the ROM data to the end
+ * of DRAM.  The linker script has already set "_eheap" as the end of DRAM,
+ * the following defines the start of region2.
+ * N.B: That ROM data consists of 2 regions, one per CPU.  If SMP is not
+ * enabled include APP's region with the heap.
+ */
+
+#ifdef CONFIG_SMP
+#  define HEAP_REGION2_START 0x3ffe4350
+#else
+#  define HEAP_REGION2_START 0x3ffe0400
+#endif
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -77,10 +97,10 @@ void up_allocate_heap(FAR void **heap_start, size_t *heap_size)
   board_autoled_on(LED_HEAPALLOCATE);
 #ifdef CONFIG_XTENSA_USE_SEPARATE_IMEM
   *heap_start = (FAR void *)&_sheap + CONFIG_XTENSA_IMEM_REGION_SIZE;
-  *heap_size = (size_t)((uintptr_t)&_eheap - (uintptr_t)*heap_start);
+  *heap_size = (size_t)(HEAP_REGION1_END - (uintptr_t)*heap_start);
 #else
   *heap_start = (FAR void *)&_sheap;
-  *heap_size = (size_t)((uintptr_t)&_eheap - (uintptr_t)&_sheap);
+  *heap_size = (size_t)(HEAP_REGION1_END - (uintptr_t)&_sheap);
 #endif
 }
 
@@ -96,6 +116,9 @@ void up_allocate_heap(FAR void **heap_start, size_t *heap_size)
 #if CONFIG_MM_REGIONS > 1
 void xtensa_add_region(void)
 {
+  umm_addregion((FAR void *)HEAP_REGION2_START,
+                (size_t)(uintptr_t)&_eheap - HEAP_REGION2_START);
+
 #if defined(CONFIG_ESP32_SPIRAM)
   /* Check for any additional memory regions */
 
@@ -105,3 +128,4 @@ void xtensa_add_region(void)
 #endif
 }
 #endif
+

boards/xtensa/esp32/esp32-core/scripts/esp32.template.ld

@@ -43,10 +43,15 @@ MEMORY
   /* Shared data RAM, excluding memory reserved for ROM bss/data/stack.
    * Enabling Bluetooth & Trace Memory features in menuconfig will decrease
    * the amount of RAM available.
+   *
+   * Note: The length of this section should be 0x50000, and this extra
+   * DRAM is available in heap at runtime. However due to static ROM memory
+   * usage at this 176KB mark, the additional static memory temporarily cannot
+   * be used.
    */
 
   dram0_0_seg (RW) :     org = 0x3ffb0000 + CONFIG_ESP32_BT_RESERVE_DRAM,
-                         len = 0x50000 - CONFIG_ESP32_TRACEMEM_RESERVE_DRAM - CONFIG_ESP32_BT_RESERVE_DRAM
+                         len = 0x2c200 - CONFIG_ESP32_TRACEMEM_RESERVE_DRAM - CONFIG_ESP32_BT_RESERVE_DRAM
 
   /* Flash mapped constant data */