From 85bb7a1428c0e1404b8f4c21fb3a32ab611f08a1 Mon Sep 17 00:00:00 2001
From: Sachin Parekh <sachin.parekh@espressif.com>
Date: Tue, 21 Apr 2020 02:53:49 +0530
Subject: [PATCH] esp32/mbedtls: Added in/out buffer allocation strategy

"Internal IRAM" strategy allocates in/out buffers in IRAM thus
saving memory in DRAM.
---
 .../espressif/boards/esp32/components/mbedtls/Kconfig | 11 +++++++++++
 .../boards/esp32/components/mbedtls/port/esp_mem.c    | 10 ++++++++++
 vendors/espressif/esp-idf                             |  2 +-
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/vendors/espressif/boards/esp32/components/mbedtls/Kconfig b/vendors/espressif/boards/esp32/components/mbedtls/Kconfig
index 42c5aeff162..e9d75794826 100644
--- a/vendors/espressif/boards/esp32/components/mbedtls/Kconfig
+++ b/vendors/espressif/boards/esp32/components/mbedtls/Kconfig
@@ -13,6 +13,7 @@ choice MBEDTLS_MEM_ALLOC_MODE
               behavior in ESP-IDF
             - Custom allocation mode, by overwriting calloc()/free() using
               mbedtls_platform_set_calloc_free() function
+            - Internal IRAM memory wherever applicable else internal DRAM
 
         Recommended mode here is always internal, since that is most preferred
         from security perspective. But if application requirement does not
@@ -32,6 +33,16 @@ config MBEDTLS_DEFAULT_MEM_ALLOC
 config MBEDTLS_CUSTOM_MEM_ALLOC
     bool "Custom alloc mode"
 
+config MBEDTLS_IRAM_8BIT_MEM_ALLOC
+    bool "Internal IRAM"
+    depends on ESP32_IRAM_AS_8BIT_ACCESSIBLE_MEMORY
+    help
+        Allows to use IRAM memory region as 8bit accessible region.
+
+        TLS input and output buffers will be allocated in IRAM section which is 32bit aligned
+        memory. Every unaligned (8bit or 16bit) access will result in an exception
+        and incur penalty of certain clock cycles per unaligned read/write.
+
 endchoice #MBEDTLS_MEM_ALLOC_MODE
 
 config MBEDTLS_SSL_MAX_CONTENT_LEN
diff --git a/vendors/espressif/boards/esp32/components/mbedtls/port/esp_mem.c b/vendors/espressif/boards/esp32/components/mbedtls/port/esp_mem.c
index c7b8e706f98..ef9392e25b4 100644
--- a/vendors/espressif/boards/esp32/components/mbedtls/port/esp_mem.c
+++ b/vendors/espressif/boards/esp32/components/mbedtls/port/esp_mem.c
@@ -25,6 +25,16 @@ IRAM_ATTR void *esp_mbedtls_mem_calloc(size_t n, size_t size)
     return heap_caps_calloc(n, size, MALLOC_CAP_INTERNAL|MALLOC_CAP_8BIT);
 #elif CONFIG_MBEDTLS_EXTERNAL_MEM_ALLOC
     return heap_caps_calloc(n, size, MALLOC_CAP_SPIRAM|MALLOC_CAP_8BIT);
+#elif CONFIG_MBEDTLS_IRAM_8BIT_MEM_ALLOC
+#ifdef CONFIG_MBEDTLS_ASYMMETRIC_CONTENT_LEN
+    if ((n*size) >= CONFIG_MBEDTLS_SSL_IN_CONTENT_LEN || (n*size) >= CONFIG_MBEDTLS_SSL_OUT_CONTENT_LEN) {
+#else
+    if ((n*size) >= CONFIG_MBEDTLS_SSL_MAX_CONTENT_LEN) {
+#endif
+        return heap_caps_calloc_prefer(n, size, 2, MALLOC_CAP_INTERNAL|MALLOC_CAP_IRAM_8BIT, MALLOC_CAP_INTERNAL|MALLOC_CAP_8BIT);
+    } else {
+        return heap_caps_calloc(n, size, MALLOC_CAP_INTERNAL|MALLOC_CAP_8BIT);
+    }
 #else
     return calloc(n, size);
 #endif
diff --git a/vendors/espressif/esp-idf b/vendors/espressif/esp-idf
index e7e0ead31ea..09b15376213 160000
--- a/vendors/espressif/esp-idf
+++ b/vendors/espressif/esp-idf
@@ -1 +1 @@
-Subproject commit e7e0ead31eaa6dc07d5b133fb0dacb7c9a45b355
+Subproject commit 09b1537621338bd5518dae055d40cd986a3b5084