AArch32: Common changes needed for BL1/BL2

This patch adds common changes to support AArch32 state in
BL1 and BL2. Following are the changes:

* Added functions for disabling MMU from Secure state.
* Added AArch32 specific SMC function.
* Added semihosting support.
* Added reporting of unhandled exceptions.
* Added uniprocessor stack support.
* Added `el3_entrypoint_common` macro that can be
  shared by BL1 and BL32 (SP_MIN) BL stages. The
  `el3_entrypoint_common` is similar to the AArch64
  counterpart with the main difference in the assembly
  instructions and the registers that are relevant to
  AArch32 execution state.
* Enabled `LOAD_IMAGE_V2` flag in Makefile for
  `ARCH=aarch32` and added check to make sure that
  platform has not overridden to disable it.

Change-Id: I33c6d8dfefb2e5d142fdfd06a0f4a7332962e1a3

2 files changed, 81 insertions, 0 deletions

diff --git a/plat/common/aarch32/platform_helpers.S b/plat/common/aarch32/platform_helpers.S
index 481dd68d..069d96d0 100644
--- a/plat/common/aarch32/platform_helpers.S
+++ b/plat/common/aarch32/platform_helpers.S
@@ -33,6 +33,7 @@
 
 	.weak	plat_my_core_pos
 	.weak	plat_reset_handler
+	.weak	plat_disable_acp
 	.weak	platform_mem_init
 	.weak	plat_panic_handler
 
@@ -59,6 +60,15 @@ func plat_reset_handler
 	bx	lr
 endfunc plat_reset_handler
 
+	/* -----------------------------------------------------
+	 * Placeholder function which should be redefined by
+	 * each platform.
+	 * -----------------------------------------------------
+	 */
+func plat_disable_acp
+	bx	lr
+endfunc plat_disable_acp
+
 	/* ---------------------------------------------------------------------
 	 * Placeholder function which should be redefined by
 	 * each platform.
diff --git a/plat/common/aarch32/platform_up_stack.S b/plat/common/aarch32/platform_up_stack.S
new file mode 100644
index 00000000..8275aec8
--- /dev/null
+++ b/plat/common/aarch32/platform_up_stack.S
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <arch.h>
+#include <asm_macros.S>
+#include <platform_def.h>
+
+	.globl	plat_get_my_stack
+	.globl	plat_set_my_stack
+
+	/* -----------------------------------------------------
+	 * unsigned long plat_get_my_stack ()
+	 *
+	 * For cold-boot BL images, only the primary CPU needs
+	 * a stack. This function returns the stack pointer for
+	 * a stack allocated in normal memory.
+	 * -----------------------------------------------------
+	 */
+func plat_get_my_stack
+	get_up_stack platform_normal_stacks, PLATFORM_STACK_SIZE
+	bx	lr
+endfunc	plat_get_my_stack
+
+	/* -----------------------------------------------------
+	 * void plat_set_my_stack ()
+	 *
+	 * For cold-boot BL images, only the primary CPU needs
+	 * a stack. This function sets the stack pointer to a
+	 * stack allocated in normal memory.
+	 * -----------------------------------------------------
+	 */
+func plat_set_my_stack
+	get_up_stack platform_normal_stacks, PLATFORM_STACK_SIZE
+	mov	sp, r0
+	bx	lr
+endfunc plat_set_my_stack
+
+	/* -----------------------------------------------------
+	 * Per-cpu stacks in normal memory. Each cpu gets a
+	 * stack of PLATFORM_STACK_SIZE bytes.
+	 * -----------------------------------------------------
+	 */
+declare_stack platform_normal_stacks, tzfw_normal_stacks, \
+		PLATFORM_STACK_SIZE, 1, CACHE_WRITEBACK_GRANULE