summaryrefslogtreecommitdiffstats
path: root/bl2/aarch32/bl2_entrypoint.S
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--bl2/aarch32/bl2_entrypoint.S136
1 files changed, 136 insertions, 0 deletions
diff --git a/bl2/aarch32/bl2_entrypoint.S b/bl2/aarch32/bl2_entrypoint.S
new file mode 100644
index 0000000..678d9c2
--- /dev/null
+++ b/bl2/aarch32/bl2_entrypoint.S
@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2016-2022, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+#include <asm_macros.S>
+#include <common/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_prefetch_abort /* Prefetch abort */
+ b report_data_abort /* Data abort */
+ b report_exception /* Reserved */
+ b report_exception /* IRQ */
+ b report_exception /* FIQ */
+
+
+func bl2_entrypoint
+ /*---------------------------------------------
+ * Save arguments x0 - x3 from BL1 for future
+ * use.
+ * ---------------------------------------------
+ */
+ mov r9, r0
+ mov r10, r1
+ mov r11, r2
+ mov r12, r3
+
+ /* ---------------------------------------------
+ * Set the exception vector to something sane.
+ * ---------------------------------------------
+ */
+ ldr r0, =bl2_vector_table
+ stcopr r0, VBAR
+ isb
+
+ /* --------------------------------------------------------
+ * Enable the instruction cache - disable speculative loads
+ * --------------------------------------------------------
+ */
+ ldcopr r0, SCTLR
+ orr r0, r0, #SCTLR_I_BIT
+ bic r0, r0, #SCTLR_DSSBS_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_END__
+ sub r1, r1, r0
+ bl zeromem
+
+#if USE_COHERENT_MEM
+ ldr r0, =__COHERENT_RAM_START__
+ ldr r1, =__COHERENT_RAM_END_UNALIGNED__
+ sub r1, r1, r0
+ 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
+
+ /* ---------------------------------------------
+ * Initialize the stack protector canary before
+ * any C code is called.
+ * ---------------------------------------------
+ */
+#if STACK_PROTECTOR_ENABLED
+ bl update_stack_protector_canary
+#endif
+
+ /* ---------------------------------------------
+ * Perform BL2 setup
+ * ---------------------------------------------
+ */
+ mov r0, r9
+ mov r1, r10
+ mov r2, r11
+ mov r3, r12
+
+ bl bl2_setup
+
+ /* ---------------------------------------------
+ * Jump to main function.
+ * ---------------------------------------------
+ */
+ bl bl2_main
+
+ /* ---------------------------------------------
+ * Should never reach this point.
+ * ---------------------------------------------
+ */
+ no_ret plat_panic_handler
+
+endfunc bl2_entrypoint