From 2ac2ce55d22e9ed6289dc7ca9ad4829f6142a6e4 Mon Sep 17 00:00:00 2001
From: Abdelatif Guettouche <abdelatif.guettouche@espressif.com>
Date: Thu, 5 Nov 2020 15:48:37 +0000
Subject: [PATCH] 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    | 28 +++++++++++++++++--
 .../esp32-core/scripts/esp32.template.ld      |  7 ++++-
 2 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/arch/xtensa/src/esp32/esp32_allocateheap.c b/arch/xtensa/src/esp32/esp32_allocateheap.c
index efb57ec06f..95effb3058 100644
--- a/arch/xtensa/src/esp32/esp32_allocateheap.c
+++ b/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
+
diff --git a/boards/xtensa/esp32/esp32-core/scripts/esp32.template.ld b/boards/xtensa/esp32/esp32-core/scripts/esp32.template.ld
index e63c7039f4..454d1e8227 100644
--- a/boards/xtensa/esp32/esp32-core/scripts/esp32.template.ld
+++ b/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 */