Add support for asynchronous FIQ handling in TSP
This patch adds support in the TSP to handle FIQ interrupts that are
generated when execution is in the TSP. S-EL1 interrupt are handled
normally and execution resumes at the instruction where the exception
was originally taken. S-EL3 interrupts i.e. any interrupt not
recognized by the TSP are handed to the TSPD. Execution resumes
normally once such an interrupt has been handled at EL3.
Change-Id: Ia3ada9a4fb15670afcc12538a6456f21efe58a8f
diff --git a/bl32/tsp/aarch64/tsp_entrypoint.S b/bl32/tsp/aarch64/tsp_entrypoint.S
index bb0880f..54276f2 100644
--- a/bl32/tsp/aarch64/tsp_entrypoint.S
+++ b/bl32/tsp/aarch64/tsp_entrypoint.S
@@ -87,7 +87,7 @@
* Set the exception vector to something sane.
* ---------------------------------------------
*/
- adr x0, early_exceptions
+ adr x0, tsp_exceptions
msr vbar_el1, x0
/* ---------------------------------------------
@@ -184,7 +184,7 @@
* Set the exception vector to something sane.
* ---------------------------------------------
*/
- adr x0, early_exceptions
+ adr x0, tsp_exceptions
msr vbar_el1, x0
/* ---------------------------------------------
diff --git a/bl32/tsp/aarch64/tsp_exceptions.S b/bl32/tsp/aarch64/tsp_exceptions.S
new file mode 100644
index 0000000..ccb4cdd
--- /dev/null
+++ b/bl32/tsp/aarch64/tsp_exceptions.S
@@ -0,0 +1,200 @@
+/*
+ * Copyright (c) 2013-2014, 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 <bl_common.h>
+#include <arch.h>
+#include <tsp.h>
+#include <asm_macros.S>
+
+
+ /* ----------------------------------------------------
+ * The caller-saved registers x0-x18 and LR are saved
+ * here.
+ * ----------------------------------------------------
+ */
+
+#define SCRATCH_REG_SIZE #(20 * 8)
+
+ .macro save_caller_regs_and_lr
+ sub sp, sp, SCRATCH_REG_SIZE
+ stp x0, x1, [sp]
+ stp x2, x3, [sp, #0x10]
+ stp x4, x5, [sp, #0x20]
+ stp x6, x7, [sp, #0x30]
+ stp x8, x9, [sp, #0x40]
+ stp x10, x11, [sp, #0x50]
+ stp x12, x13, [sp, #0x60]
+ stp x14, x15, [sp, #0x70]
+ stp x16, x17, [sp, #0x80]
+ stp x18, x30, [sp, #0x90]
+ .endm
+
+ .macro restore_caller_regs_and_lr
+ ldp x0, x1, [sp]
+ ldp x2, x3, [sp, #0x10]
+ ldp x4, x5, [sp, #0x20]
+ ldp x6, x7, [sp, #0x30]
+ ldp x8, x9, [sp, #0x40]
+ ldp x10, x11, [sp, #0x50]
+ ldp x12, x13, [sp, #0x60]
+ ldp x14, x15, [sp, #0x70]
+ ldp x16, x17, [sp, #0x80]
+ ldp x18, x30, [sp, #0x90]
+ add sp, sp, SCRATCH_REG_SIZE
+ .endm
+
+ .globl tsp_exceptions
+
+ /* -----------------------------------------------------
+ * TSP exception handlers.
+ * -----------------------------------------------------
+ */
+ .section .vectors, "ax"; .align 11
+
+ .align 7
+tsp_exceptions:
+ /* -----------------------------------------------------
+ * Current EL with _sp_el0 : 0x0 - 0x180. No exceptions
+ * are expected and treated as irrecoverable errors.
+ * -----------------------------------------------------
+ */
+sync_exception_sp_el0:
+ wfi
+ b sync_exception_sp_el0
+ check_vector_size sync_exception_sp_el0
+
+ .align 7
+
+irq_sp_el0:
+ b irq_sp_el0
+ check_vector_size irq_sp_el0
+
+ .align 7
+fiq_sp_el0:
+ b fiq_sp_el0
+ check_vector_size fiq_sp_el0
+
+ .align 7
+serror_sp_el0:
+ b serror_sp_el0
+ check_vector_size serror_sp_el0
+
+
+ /* -----------------------------------------------------
+ * Current EL with SPx: 0x200 - 0x380. Only IRQs/FIQs
+ * are expected and handled
+ * -----------------------------------------------------
+ */
+ .align 7
+sync_exception_sp_elx:
+ wfi
+ b sync_exception_sp_elx
+ check_vector_size sync_exception_sp_elx
+
+ .align 7
+irq_sp_elx:
+ b irq_sp_elx
+ check_vector_size irq_sp_elx
+
+ .align 7
+fiq_sp_elx:
+ save_caller_regs_and_lr
+ bl tsp_fiq_handler
+ cbz x0, fiq_sp_elx_done
+
+ /*
+ * This FIQ was not targetted to S-EL1 so send it to
+ * the monitor and wait for execution to resume.
+ */
+ smc #0
+fiq_sp_elx_done:
+ restore_caller_regs_and_lr
+ eret
+ check_vector_size fiq_sp_elx
+
+ .align 7
+serror_sp_elx:
+ b serror_sp_elx
+ check_vector_size serror_sp_elx
+
+
+ /* -----------------------------------------------------
+ * Lower EL using AArch64 : 0x400 - 0x580. No exceptions
+ * are handled since TSP does not implement a lower EL
+ * -----------------------------------------------------
+ */
+ .align 7
+sync_exception_aarch64:
+ wfi
+ b sync_exception_aarch64
+ check_vector_size sync_exception_aarch64
+
+ .align 7
+irq_aarch64:
+ b irq_aarch64
+ check_vector_size irq_aarch64
+
+ .align 7
+fiq_aarch64:
+ b fiq_aarch64
+ check_vector_size fiq_aarch64
+
+ .align 7
+serror_aarch64:
+ b serror_aarch64
+ check_vector_size serror_aarch64
+
+
+ /* -----------------------------------------------------
+ * Lower EL using AArch32 : 0x600 - 0x780. No exceptions
+ * handled since the TSP does not implement a lower EL.
+ * -----------------------------------------------------
+ */
+ .align 7
+sync_exception_aarch32:
+ wfi
+ b sync_exception_aarch32
+ check_vector_size sync_exception_aarch32
+
+ .align 7
+irq_aarch32:
+ b irq_aarch32
+ check_vector_size irq_aarch32
+
+ .align 7
+fiq_aarch32:
+ b fiq_aarch32
+ check_vector_size fiq_aarch32
+
+ .align 7
+serror_aarch32:
+ b serror_aarch32
+ check_vector_size serror_aarch32
+ .align 7
diff --git a/bl32/tsp/tsp.mk b/bl32/tsp/tsp.mk
index 297556b..b9084d5 100644
--- a/bl32/tsp/tsp.mk
+++ b/bl32/tsp/tsp.mk
@@ -30,6 +30,7 @@
BL32_SOURCES += bl32/tsp/tsp_main.c \
bl32/tsp/aarch64/tsp_entrypoint.S \
+ bl32/tsp/aarch64/tsp_exceptions.S \
bl32/tsp/aarch64/tsp_request.S \
bl32/tsp/tsp_interrupt.c \
bl32/tsp/tsp_timer.c \