Add support for asynchronous FIQ handling in TSP
authorAchin Gupta <achin.gupta@arm.com>
Fri, 9 May 2014 11:17:56 +0000 (12:17 +0100)
committerAchin Gupta <achin.gupta@arm.com>
Thu, 22 May 2014 16:48:38 +0000 (17:48 +0100)
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

bl32/tsp/aarch64/tsp_entrypoint.S
bl32/tsp/aarch64/tsp_exceptions.S [new file with mode: 0644]
bl32/tsp/tsp.mk

index bb0880ffa23c3f08b55189439a078d6b2726099e..54276f2c6eefdb48279703492354039b63440c3c 100644 (file)
@@ -87,7 +87,7 @@ func tsp_entrypoint
         * Set the exception vector to something sane.
         * ---------------------------------------------
         */
-       adr     x0, early_exceptions
+       adr     x0, tsp_exceptions
        msr     vbar_el1, x0
 
        /* ---------------------------------------------
@@ -184,7 +184,7 @@ func tsp_cpu_on_entry
         * 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 (file)
index 0000000..ccb4cdd
--- /dev/null
@@ -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
index 297556bb894856b82d018806deb5e728a74a7f8b..b9084d549eacc2e934e914570437f36134ac89cf 100644 (file)
@@ -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                    \