AArch32: Add BL2U support
Add support for firmware upgrade on AArch32.
This patch has been tested on the FVP models.
NOTE: Firmware upgrade on Juno AArch32 is not currently supported.
Change-Id: I1ca8078214eaf86b46463edd14740120af930aec
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>
Co-Authored-By: Yatharth Kochar <yatharth.kochar@arm.com>
diff --git a/bl2u/aarch32/bl2u_entrypoint.S b/bl2u/aarch32/bl2u_entrypoint.S
new file mode 100644
index 0000000..1fa669e
--- /dev/null
+++ b/bl2u/aarch32/bl2u_entrypoint.S
@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+#include <asm_macros.S>
+#include <bl_common.h>
+
+
+ .globl bl2u_vector_table
+ .globl bl2u_entrypoint
+
+
+vector_base bl2u_vector_table
+ b bl2u_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 bl2u_entrypoint
+ /*---------------------------------------------
+ * Save from r1 the extents of the trusted ram
+ * available to BL2U for future use.
+ * r0 is not currently used.
+ * ---------------------------------------------
+ */
+ mov r11, r1
+ mov r12, r2
+
+ /* ---------------------------------------------
+ * Set the exception vector to something sane.
+ * ---------------------------------------------
+ */
+ ldr r0, =bl2u_vector_table
+ stcopr r0, VBAR
+ isb
+
+ /* -----------------------------------------------------
+ * Enable the instruction cache
+ * -----------------------------------------------------
+ */
+ ldcopr r0, SCTLR
+ orr r0, r0, #SCTLR_I_BIT
+ stcopr r0, SCTLR
+ isb
+
+ /* ---------------------------------------------
+ * Since BL2U executes after BL1, it is assumed
+ * here that BL1 has already has done the
+ * necessary register initializations.
+ * ---------------------------------------------
+ */
+
+ /* ---------------------------------------------
+ * Invalidate the RW memory used by the BL2U
+ * 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
+
+ /* --------------------------------------------
+ * 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
+
+ /* ---------------------------------------------
+ * Initialize the stack protector canary before
+ * any C code is called.
+ * ---------------------------------------------
+ */
+#if STACK_PROTECTOR_ENABLED
+ bl update_stack_protector_canary
+#endif
+
+ /* ---------------------------------------------
+ * Perform early platform setup & platform
+ * specific early arch. setup e.g. mmu setup
+ * ---------------------------------------------
+ */
+ mov r0, r11
+ mov r1, r12
+ bl bl2u_early_platform_setup
+ bl bl2u_plat_arch_setup
+
+ /* ---------------------------------------------
+ * Jump to main function.
+ * ---------------------------------------------
+ */
+ bl bl2u_main
+
+ /* ---------------------------------------------
+ * Should never reach this point.
+ * ---------------------------------------------
+ */
+ no_ret plat_panic_handler
+
+endfunc bl2u_entrypoint