From b9f06dc5e31d0bc78637142f576b9339bb86ee31 Mon Sep 17 00:00:00 2001
From: Dimitry Kloper <dikloper@cisco.com>
Date: Mon, 4 Jan 2016 21:39:48 +0200
Subject: [PATCH 1/2] ATMEGA2560: Fix compilation when CONFIG_DISABLE_SIGNALS
 is undefined

---
 arch/avr/include/avr/irq.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/avr/include/avr/irq.h b/arch/avr/include/avr/irq.h
index 9e95edbec5f..9c8ec670afc 100644
--- a/arch/avr/include/avr/irq.h
+++ b/arch/avr/include/avr/irq.h
@@ -117,6 +117,9 @@ struct xcptcontext
 
   uint8_t saved_pc1;
   uint8_t saved_pc0;
+# if defined(REG_PC2)
+  uint8_t saved_pc2;
+# endif   
   uint8_t saved_sreg;
 #endif
 

From 16212f19e77ebadd0589e7d85c3c8530a8fdd00f Mon Sep 17 00:00:00 2001
From: Dimitry Kloper <dikloper@cisco.com>
Date: Mon, 4 Jan 2016 21:42:24 +0200
Subject: [PATCH 2/2] AVR: Introduce Atmel Toolchain as a configuration option

Atmel's AVR8 toolchain is similar to WinAVR, but at present moment
it has one important feature that WinAVR does not. The __flash and __memx
allow built in comiler support for transparent program memory pointers.
Functions that use such pointers will work both with RAM arrays and
flash memory arrays. The compiler generates an appropriate code automatically.
For systems with tiny memory like atmega, this is very important and
allows to move all static const strings into flash.
---
 arch/avr/src/avr/Kconfig        | 24 ++++++++++++++++++++++++
 arch/avr/src/avr/Toolchain.defs | 16 +++++++++++++++-
 2 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/arch/avr/src/avr/Kconfig b/arch/avr/src/avr/Kconfig
index 9591cb6530d..5010dc57b36 100644
--- a/arch/avr/src/avr/Kconfig
+++ b/arch/avr/src/avr/Kconfig
@@ -27,6 +27,14 @@ config AVR_WINAVR
 		correct cygwin.dll file precedes the path to the WinAVR
 		binaries!
 
+config AVR_ATMEL_AVR_TOOLCHAIN
+	bool "Atmel AVR Toolchain"
+	depends on HOST_WINDOWS
+	---help---
+                Atmel provides GNU Toolchain for AVR development. It can
+                be obtained by installing Atmel Studio 6 and later or
+                as standalone package from Atmel.
+
 config AVR_LINUXGCC
 	bool "Linux GCC"
 	depends on HOST_LINUX
@@ -59,4 +67,20 @@ config AVR_BUILDROOT
 
 endchoice
 
+menu "Atmel AVR Toolchain options"
+	depends on AVR_ATMEL_AVR_TOOLCHAIN
+
+config AVR_HAS_MEMX_PTR
+	bool "Enable in-flash static const stings"
+	depends on AVR_ATMEL_AVR_TOOLCHAIN
+	default y
+	---help---
+                Enabling this option (recommended) will place all constant
+                strings used for debugging and assertion in program memory
+                and allow the corresponding routines to get the strings
+                directly from there. This will dramatically decrease amount
+                of RAM needed to hold this static data.
+                
+endmenu
+
 endif
diff --git a/arch/avr/src/avr/Toolchain.defs b/arch/avr/src/avr/Toolchain.defs
index 38e54521d5d..7e9e74210fa 100644
--- a/arch/avr/src/avr/Toolchain.defs
+++ b/arch/avr/src/avr/Toolchain.defs
@@ -66,6 +66,12 @@ ifeq ($(filter y, \
   CONFIG_AVR_TOOLCHAIN ?= WINAVR
 endif
 
+ifeq ($(filter y, \
+      $(CONFIG_AVR_ATMEL_AVR_TOOLCHAIN) \
+    ),y)
+  CONFIG_AVR_TOOLCHAIN ?= ATMEL
+endif
+
 # Chip-specific CPU flags
 
 ifeq ($(CONFIG_ARCH_CHIP_ATMEGA128),y)
@@ -114,9 +120,17 @@ ifeq ($(CONFIG_AVR_TOOLCHAIN),LINUXGCC)
   LDFLAGS += -nostartfiles -nodefaultlibs
 endif
 
-# WinAVR toolchain under Windows/Cygwin
+# WinAVR or Atmel toolchain under Windows/Cygwin
 
+_WINAVR = 0
 ifeq ($(CONFIG_AVR_TOOLCHAIN),WINAVR)
+_WINAVR = 1
+endif
+ifeq ($(CONFIG_AVR_TOOLCHAIN),ATMEL)
+_WINAVR = 1
+endif
+
+ifeq ($(_WINAVR),1)
   CROSSDEV ?= avr-
   ifneq ($(CONFIG_WINDOWS_NATIVE),y)
     WINTOOL = y