AArch32: Add generic changes in BL2

This patch adds generic changes in BL2 to support AArch32 state.
New AArch32 specific assembly/C files are introduced and
some files are moved to AArch32/64 specific folders.
BL2 for AArch64 is refactored but functionally identical.

BL2 executes in Secure SVC mode in AArch32 state.

Change-Id: Ifaacbc2a91f8640876385b953adb24744d9dbde3

4 files changed, 201 insertions, 5 deletions

diff --git a/bl2/aarch32/bl2_arch_setup.c b/bl2/aarch32/bl2_arch_setup.c
new file mode 100644
index 00000000..665c29c6
--- /dev/null
+++ b/bl2/aarch32/bl2_arch_setup.c
@@ -0,0 +1,39 @@
+/*
+ * 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.
+ */
+
+
+/*******************************************************************************
+ * Place holder function to perform any Secure SVC specific architectural
+ * setup. At the moment there is nothing to do.
+ ******************************************************************************/
+void bl2_arch_setup(void)
+{
+
+}
diff --git a/bl2/aarch32/bl2_entrypoint.S b/bl2/aarch32/bl2_entrypoint.S
new file mode 100644
index 00000000..6c620e22
--- /dev/null
+++ b/bl2/aarch32/bl2_entrypoint.S
@@ -0,0 +1,145 @@
+/*
+ * 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 <bl_common.h>
+
+
+	.globl	bl2_vector_table
+	.globl	bl2_entrypoint
+
+
+vector_base bl2_vector_table
+	b	bl2_entrypoint
+	b	report_exception	/* Undef */
+	b	report_exception	/* SVC call */
+	b	report_exception	/* Prefetch abort */
+	b	report_exception	/* Data abort */
+	b	report_exception	/* Reserved */
+	b	report_exception	/* IRQ */
+	b	report_exception	/* FIQ */
+
+
+func bl2_entrypoint
+	/*---------------------------------------------
+	 * Save from r1 the extents of the trusted ram
+	 * available to BL2 for future use.
+	 * r0 is not currently used.
+	 * ---------------------------------------------
+	 */
+ 	mov	r11, r1
+
+	/* ---------------------------------------------
+	 * Set the exception vector to something sane.
+	 * ---------------------------------------------
+	 */
+	ldr	r0, =bl2_vector_table
+	stcopr	r0, VBAR
+	isb
+
+	/* -----------------------------------------------------
+	 * Enable the instruction cache
+	 * -----------------------------------------------------
+	 */
+	ldcopr	r0, SCTLR
+	orr	r0, r0, #SCTLR_I_BIT
+	stcopr	r0, SCTLR
+	isb
+
+	/* ---------------------------------------------
+	 * Since BL2 executes after BL1, it is assumed
+	 * here that BL1 has already has done the
+	 * necessary register initializations.
+	 * ---------------------------------------------
+	 */
+
+	/* ---------------------------------------------
+	 * Invalidate the RW memory used by the BL2
+	 * image. This includes the data and NOBITS
+	 * sections. This is done to safeguard against
+	 * possible corruption of this memory by dirty
+	 * cache lines in a system cache as a result of
+	 * use by an earlier boot loader stage.
+	 * ---------------------------------------------
+	 */
+	ldr	r0, =__RW_START__
+	ldr	r1, =__RW_END__
+	sub	r1, r1, r0
+	bl	inv_dcache_range
+
+	/* ---------------------------------------------
+	 * Zero out NOBITS sections. There are 2 of them:
+	 *   - the .bss section;
+	 *   - the coherent memory section.
+	 * ---------------------------------------------
+	 */
+	ldr	r0, =__BSS_START__
+	ldr	r1, =__BSS_SIZE__
+	bl	zeromem
+
+#if USE_COHERENT_MEM
+	ldr	r0, =__COHERENT_RAM_START__
+	ldr	r1, =__COHERENT_RAM_UNALIGNED_SIZE__
+	bl	zeromem
+#endif
+
+	/* --------------------------------------------
+	 * Allocate a stack whose memory will be marked
+	 * as Normal-IS-WBWA when the MMU is enabled.
+	 * There is no risk of reading stale stack
+	 * memory after enabling the MMU as only the
+	 * primary cpu is running at the moment.
+	 * --------------------------------------------
+	 */
+	bl	plat_set_my_stack
+
+	/* ---------------------------------------------
+	 * Perform early platform setup & platform
+	 * specific early arch. setup e.g. mmu setup
+	 * ---------------------------------------------
+	 */
+	mov	r0, r11
+	bl	bl2_early_platform_setup
+	bl	bl2_plat_arch_setup
+
+	/* ---------------------------------------------
+	 * Jump to main function.
+	 * ---------------------------------------------
+	 */
+	bl	bl2_main
+
+	/* ---------------------------------------------
+	 * Should never reach this point.
+	 * ---------------------------------------------
+	 */
+	bl	plat_panic_handler
+
+endfunc bl2_entrypoint
diff --git a/bl2/bl2.mk b/bl2/bl2.mk
index 6cb478d1..f823ef46 100644
--- a/bl2/bl2.mk
+++ b/bl2/bl2.mk
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
+# Copyright (c) 2013-2016, 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:
@@ -29,10 +29,13 @@
 #
 
 BL2_SOURCES		+=	bl2/bl2_main.c				\
-				bl2/aarch64/bl2_entrypoint.S		\
-				bl2/aarch64/bl2_arch_setup.c		\
-				common/aarch64/early_exceptions.S	\
-				lib/locks/exclusive/aarch64/spinlock.S
+				bl2/${ARCH}/bl2_entrypoint.S		\
+				bl2/${ARCH}/bl2_arch_setup.c		\
+				lib/locks/exclusive/${ARCH}/spinlock.S
+
+ifeq (${ARCH},aarch64)
+BL2_SOURCES		+=	common/aarch64/early_exceptions.S
+endif
 
 ifeq (${LOAD_IMAGE_V2},1)
 BL2_SOURCES		+=	bl2/bl2_image_load_v2.c
diff --git a/bl2/bl2_main.c b/bl2/bl2_main.c
index fc93e1b1..514c0053 100644
--- a/bl2/bl2_main.c
+++ b/bl2/bl2_main.c
@@ -60,6 +60,15 @@ void bl2_main(void)
 	/* Load the subsequent bootloader images. */
 	next_bl_ep_info = bl2_load_images();
 
+#ifdef AARCH32
+	/*
+	 * For AArch32 state BL1 and BL2 share the MMU setup.
+	 * Given that BL2 does not map BL1 regions, MMU needs
+	 * to be disabled in order to go back to BL1.
+	 */
+	disable_mmu_icache_secure();
+#endif /* AARCH32 */
+
 	/*
 	 * Run next BL image via an SMC to BL1. Information on how to pass
 	 * control to the BL32 (if present) and BL33 software images will