[rtems commit] bsps/arm: Invalidate branch predictors earlier
Sebastian Huber
sebh at rtems.org
Wed Dec 23 09:26:45 UTC 2020
Module: rtems
Branch: master
Commit: 76a1a5378031e56d29d16c713aee73c6747c3e61
Changeset: http://git.rtems.org/rtems/commit/?id=76a1a5378031e56d29d16c713aee73c6747c3e61
Author: Sebastian Huber <sebastian.huber at embedded-brains.de>
Date: Mon Dec 21 07:29:41 2020 +0100
bsps/arm: Invalidate branch predictors earlier
Make sure the branch predictors are invalidated before the first branch
is executed.
Update #4202.
---
bsps/arm/include/bsp/arm-a9mpcore-start.h | 2 --
bsps/arm/raspberrypi/start/bspstarthooks.c | 1 -
bsps/arm/shared/start/start.S | 11 +++++++++++
bsps/arm/xilinx-zynq/start/bspstarthooks.c | 1 -
bsps/arm/xilinx-zynqmp/start/bspstarthooks.c | 1 -
5 files changed, 11 insertions(+), 5 deletions(-)
diff --git a/bsps/arm/include/bsp/arm-a9mpcore-start.h b/bsps/arm/include/bsp/arm-a9mpcore-start.h
index f377745..38ddb03 100644
--- a/bsps/arm/include/bsp/arm-a9mpcore-start.h
+++ b/bsps/arm/include/bsp/arm-a9mpcore-start.h
@@ -141,8 +141,6 @@ BSP_START_TEXT_SECTION static inline void arm_a9mpcore_start_hook_0(void)
(volatile a9mpcore_scu *) BSP_ARM_A9MPCORE_SCU_BASE;
uint32_t cpu_id = arm_cortex_a9_get_multiprocessor_cpu_id();
- arm_cp15_branch_predictor_invalidate_all();
-
if (cpu_id == 0) {
arm_a9mpcore_start_scu_enable(scu);
}
diff --git a/bsps/arm/raspberrypi/start/bspstarthooks.c b/bsps/arm/raspberrypi/start/bspstarthooks.c
index c46c4f5..b050cb6 100644
--- a/bsps/arm/raspberrypi/start/bspstarthooks.c
+++ b/bsps/arm/raspberrypi/start/bspstarthooks.c
@@ -110,7 +110,6 @@ void BSP_START_TEXT_SECTION bsp_start_hook_0(void)
rtems_cache_invalidate_entire_data();
}
rtems_cache_invalidate_entire_instruction();
- arm_cp15_branch_predictor_invalidate_all();
arm_cp15_tlb_invalidate();
arm_cp15_flush_prefetch_buffer();
diff --git a/bsps/arm/shared/start/start.S b/bsps/arm/shared/start/start.S
index 9ebc281..f4880df 100644
--- a/bsps/arm/shared/start/start.S
+++ b/bsps/arm/shared/start/start.S
@@ -181,6 +181,17 @@ _start:
mov r13, #0
#endif
+#if __ARM_ARCH >= 7
+ /*
+ * Write to BPIALL (Branch Predictor Invalidate All) to invalidate all
+ * branch predictors. There is no need to use BPIALLIS (Branch
+ * Predictor Invalidate All, Inner Shareable) since this code is
+ * executed on all processors used by RTEMS.
+ */
+ mov r0, #0
+ mcr p15, 0, r0, c7, c5, 6
+#endif
+
#ifdef RTEMS_SMP
/* Read MPIDR and get current processor index */
mrc p15, 0, r7, c0, c0, 5
diff --git a/bsps/arm/xilinx-zynq/start/bspstarthooks.c b/bsps/arm/xilinx-zynq/start/bspstarthooks.c
index a0f0fba..0fc2a25 100644
--- a/bsps/arm/xilinx-zynq/start/bspstarthooks.c
+++ b/bsps/arm/xilinx-zynq/start/bspstarthooks.c
@@ -66,7 +66,6 @@ BSP_START_TEXT_SECTION void bsp_start_hook_0(void)
* are required there.
*/
arm_cp15_data_cache_invalidate_all_levels();
- arm_cp15_branch_predictor_invalidate_all();
arm_cp15_tlb_invalidate();
arm_cp15_flush_prefetch_buffer();
arm_a9mpcore_start_hook_0();
diff --git a/bsps/arm/xilinx-zynqmp/start/bspstarthooks.c b/bsps/arm/xilinx-zynqmp/start/bspstarthooks.c
index 9ab8d96..bc3f0fb 100644
--- a/bsps/arm/xilinx-zynqmp/start/bspstarthooks.c
+++ b/bsps/arm/xilinx-zynqmp/start/bspstarthooks.c
@@ -72,7 +72,6 @@ BSP_START_TEXT_SECTION void bsp_start_hook_0(void)
* are required there.
*/
arm_cp15_data_cache_invalidate_all_levels();
- arm_cp15_branch_predictor_invalidate_all();
arm_cp15_tlb_invalidate();
arm_cp15_flush_prefetch_buffer();
}
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