Merge pull request #1523 from jts-arm/dsu
DSU erratum 936184 workaround
diff --git a/bl1/bl1.mk b/bl1/bl1.mk
index 9a46a34..ec7d728 100644
--- a/bl1/bl1.mk
+++ b/bl1/bl1.mk
@@ -1,5 +1,5 @@
#
-# Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
+# Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
#
# SPDX-License-Identifier: BSD-3-Clause
#
@@ -17,7 +17,8 @@
${MBEDTLS_SOURCES}
ifeq (${ARCH},aarch64)
-BL1_SOURCES += lib/el3_runtime/aarch64/context.S
+BL1_SOURCES += lib/cpus/aarch64/dsu_helpers.S \
+ lib/el3_runtime/aarch64/context.S
endif
ifeq (${TRUSTED_BOARD_BOOT},1)
diff --git a/bl2/bl2.mk b/bl2/bl2.mk
index 7e33703..af30a81 100644
--- a/bl2/bl2.mk
+++ b/bl2/bl2.mk
@@ -1,5 +1,5 @@
#
-# Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
+# Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
#
# SPDX-License-Identifier: BSD-3-Clause
#
@@ -29,5 +29,10 @@
bl2/${ARCH}/bl2_el3_exceptions.S \
lib/cpus/${ARCH}/cpu_helpers.S \
lib/cpus/errata_report.c
+
+ifeq (${ARCH},aarch64)
+BL2_SOURCES += lib/cpus/aarch64/dsu_helpers.S
+endif
+
BL2_LINKERFILE := bl2/bl2_el3.ld.S
endif
diff --git a/bl31/bl31.mk b/bl31/bl31.mk
index bff9653..066c701 100644
--- a/bl31/bl31.mk
+++ b/bl31/bl31.mk
@@ -24,6 +24,7 @@
bl31/bl31_context_mgmt.c \
common/runtime_svc.c \
lib/aarch64/setjmp.S \
+ lib/cpus/aarch64/dsu_helpers.S \
plat/common/aarch64/platform_mp_stack.S \
services/arm_arch_svc/arm_arch_svc_setup.c \
services/std_svc/std_svc_setup.c \
diff --git a/docs/cpu-specific-build-macros.rst b/docs/cpu-specific-build-macros.rst
index c11f640..151c99e 100644
--- a/docs/cpu-specific-build-macros.rst
+++ b/docs/cpu-specific-build-macros.rst
@@ -68,10 +68,10 @@
with different revisions of a processor has no runtime mechanism available
for it to specify which errata workarounds should be enabled or not.
-The value of the build flags are 0 by default, that is, disabled. Any other
-value will enable it.
+The value of the build flags is 0 by default, that is, disabled. A value of 1
+will enable it.
-For Cortex-A53, following errata build flags are defined :
+For Cortex-A53, the following errata build flags are defined :
- ``ERRATA_A53_826319``: This applies errata 826319 workaround to Cortex-A53
CPU. This needs to be enabled only for revision <= r0p2 of the CPU.
@@ -97,7 +97,7 @@
Earlier revisions of the CPU have other errata which require the same
workaround in software, so they should be covered anyway.
-For Cortex-A57, following errata build flags are defined :
+For Cortex-A57, the following errata build flags are defined :
- ``ERRATA_A57_806969``: This applies errata 806969 workaround to Cortex-A57
CPU. This needs to be enabled only for revision r0p0 of the CPU.
@@ -127,11 +127,33 @@
CPU. This needs to be enabled only for revision <= r1p3 of the CPU.
-For Cortex-A72, following errata build flags are defined :
+For Cortex-A72, the following errata build flags are defined :
- ``ERRATA_A72_859971``: This applies errata 859971 workaround to Cortex-A72
CPU. This needs to be enabled only for revision <= r0p3 of the CPU.
+DSU Errata Workarounds
+----------------------
+
+Similar to CPU errata, TF-A also implements workarounds for DSU (DynamIQ
+Shared Unit) errata. The DSU errata details can be found in the respective Arm
+documentation:
+
+- `Arm DSU Software Developers Errata Notice`_.
+
+Each erratum is identified by an ``ID``, as defined in the DSU errata notice
+document. Thus, the build flags which enable/disable the errata workarounds
+have the format ``ERRATA_DSU_<ID>``. The implementation and application logic
+of DSU errata workarounds are similar to `CPU errata workarounds`_.
+
+For DSU errata, the following build flags are defined:
+
+- ``ERRATA_DSU_936184``: This applies errata 936184 workaround for the
+ affected DSU configurations. This errata applies only for those DSUs that
+ contain the ACP interface **and** the DSU revision is older than r2p0 (on
+ r2p0 it is fixed). However, please note that this workaround results in
+ increased DSU power consumption on idle.
+
CPU Specific optimizations
--------------------------
@@ -171,3 +193,4 @@
.. _Cortex-A72 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm012079/index.html
.. _Firmware Design guide: firmware-design.rst
.. _Cortex-A57 Software Optimization Guide: http://infocenter.arm.com/help/topic/com.arm.doc.uan0015b/Cortex_A57_Software_Optimization_Guide_external.pdf
+.. _Arm DSU Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm138168/index.html
\ No newline at end of file
diff --git a/include/lib/cpus/aarch64/dsu_def.h b/include/lib/cpus/aarch64/dsu_def.h
new file mode 100644
index 0000000..0e2d93a
--- /dev/null
+++ b/include/lib/cpus/aarch64/dsu_def.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef DSU_DEF_H
+#define DSU_DEF_H
+
+#include <utils_def.h>
+
+/********************************************************************
+ * DSU control registers definitions *
+ ********************************************************************/
+#define CLUSTERCFR_EL1 S3_0_C15_C3_0
+#define CLUSTERIDR_EL1 S3_0_C15_C3_1
+#define CLUSTERACTLR_EL1 S3_0_C15_C3_3
+
+/********************************************************************
+ * DSU control registers bit fields *
+ ********************************************************************/
+#define CLUSTERIDR_REV_SHIFT U(0)
+#define CLUSTERIDR_REV_BITS U(4)
+#define CLUSTERIDR_VAR_SHIFT U(4)
+#define CLUSTERIDR_VAR_BITS U(4)
+#define CLUSTERCFR_ACP_SHIFT U(11)
+
+/********************************************************************
+ * Masks applied for DSU errata workarounds *
+ ********************************************************************/
+#define DSU_ERRATA_936184_MASK (ULL(0x3) << 15)
+
+#endif /* DSU_DEF_H */
diff --git a/lib/cpus/aarch64/cortex_a55.S b/lib/cpus/aarch64/cortex_a55.S
index 741c773..4e9bd9f 100644
--- a/lib/cpus/aarch64/cortex_a55.S
+++ b/lib/cpus/aarch64/cortex_a55.S
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -11,6 +11,14 @@
#include <cpu_macros.S>
#include <plat_macros.S>
+func cortex_a55_reset_func
+ mov x19, x30
+#if ERRATA_DSU_936184
+ bl errata_dsu_936184_wa
+#endif
+ ret x19
+endfunc cortex_a55_reset_func
+
/* ---------------------------------------------
* HW will do the cache maintenance while powering down
* ---------------------------------------------
@@ -27,6 +35,26 @@
ret
endfunc cortex_a55_core_pwr_dwn
+#if REPORT_ERRATA
+/*
+ * Errata printing function for Cortex A55. Must follow AAPCS & can use stack.
+ */
+func cortex_a55_errata_report
+ stp x8, x30, [sp, #-16]!
+ bl cpu_get_rev_var
+ mov x8, x0
+
+ /*
+ * Report all errata. The revision variant information is at x8, where
+ * "report_errata" is expecting it and it doesn't corrupt it.
+ */
+ report_errata ERRATA_DSU_936184, cortex_a55, dsu_936184
+
+ ldp x8, x30, [sp], #16
+ ret
+endfunc cortex_a55_errata_report
+#endif
+
/* ---------------------------------------------
* This function provides cortex_a55 specific
* register information for crash reporting.
@@ -47,5 +75,5 @@
endfunc cortex_a55_cpu_reg_dump
declare_cpu_ops cortex_a55, CORTEX_A55_MIDR, \
- CPU_NO_RESET_FUNC, \
+ cortex_a55_reset_func, \
cortex_a55_core_pwr_dwn
diff --git a/lib/cpus/aarch64/cortex_a75.S b/lib/cpus/aarch64/cortex_a75.S
index 73f566f..e121b7d 100644
--- a/lib/cpus/aarch64/cortex_a75.S
+++ b/lib/cpus/aarch64/cortex_a75.S
@@ -11,6 +11,7 @@
#include <cpu_macros.S>
func cortex_a75_reset_func
+ mov x19, x30
#if IMAGE_BL31 && WORKAROUND_CVE_2017_5715
cpu_check_csv2 x0, 1f
adr x0, wa_cve_2017_5715_bpiall_vbar
@@ -26,6 +27,10 @@
isb
#endif
+#if ERRATA_DSU_936184
+ bl errata_dsu_936184_wa
+#endif
+
#if ENABLE_AMU
/* Make sure accesses from EL0/EL1 and EL2 are not trapped to EL3 */
mrs x0, actlr_el3
@@ -49,7 +54,7 @@
msr CPUAMCNTENSET_EL0, x0
isb
#endif
- ret
+ ret x19
endfunc cortex_a75_reset_func
func check_errata_cve_2017_5715
@@ -106,6 +111,7 @@
*/
report_errata WORKAROUND_CVE_2017_5715, cortex_a75, cve_2017_5715
report_errata WORKAROUND_CVE_2018_3639, cortex_a75, cve_2018_3639
+ report_errata ERRATA_DSU_936184, cortex_a75, dsu_936184
ldp x8, x30, [sp], #16
ret
diff --git a/lib/cpus/aarch64/cortex_a76.S b/lib/cpus/aarch64/cortex_a76.S
index 51d0b15..1697c55 100644
--- a/lib/cpus/aarch64/cortex_a76.S
+++ b/lib/cpus/aarch64/cortex_a76.S
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -207,6 +207,7 @@
endfunc cortex_a76_disable_wa_cve_2018_3639
func cortex_a76_reset_func
+ mov x19, x30
#if WORKAROUND_CVE_2018_3639
mrs x0, CORTEX_A76_CPUACTLR2_EL1
orr x0, x0, #CORTEX_A76_CPUACTLR2_EL1_DISABLE_LOAD_PASS_STORE
@@ -224,7 +225,11 @@
msr vbar_el3, x0
isb
#endif
- ret
+
+#if ERRATA_DSU_936184
+ bl errata_dsu_936184_wa
+#endif
+ ret x19
endfunc cortex_a76_reset_func
/* ---------------------------------------------
@@ -258,6 +263,7 @@
* checking functions of each errata.
*/
report_errata WORKAROUND_CVE_2018_3639, cortex_a76, cve_2018_3639
+ report_errata ERRATA_DSU_936184, cortex_a76, dsu_936184
ldp x8, x30, [sp], #16
ret
diff --git a/lib/cpus/aarch64/dsu_helpers.S b/lib/cpus/aarch64/dsu_helpers.S
new file mode 100644
index 0000000..293ed24
--- /dev/null
+++ b/lib/cpus/aarch64/dsu_helpers.S
@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <asm_macros.S>
+#include <dsu_def.h>
+#include <errata_report.h>
+
+/*
+ * DSU erratum 936184
+ * Check the DSU variant, revision and configuration to determine if the
+ * erratum applies. This erratum was fixed in r2p0.
+ *
+ * This function is called from both assembly and C environment. So it
+ * follows AAPCS.
+ *
+ * Clobbers: x0-x3
+ */
+ .globl check_errata_dsu_936184
+ .globl errata_dsu_936184_wa
+
+func check_errata_dsu_936184
+ mov x2, #ERRATA_NOT_APPLIES
+ mov x3, #ERRATA_APPLIES
+
+ /* Erratum applies only if ACP interface is present in DSU */
+ mov x0, x2
+ mrs x1, CLUSTERCFR_EL1
+ ubfx x1, x1, #CLUSTERCFR_ACP_SHIFT, #1
+ cbz x1, 1f
+
+ /* If ACP is present, check if DSU is older than r2p0 */
+ mrs x1, CLUSTERIDR_EL1
+
+ /* DSU variant and revision bitfields in CLUSTERIDR are adjacent */
+ ubfx x0, x1, #CLUSTERIDR_REV_SHIFT,\
+ #(CLUSTERIDR_REV_BITS + CLUSTERIDR_VAR_BITS)
+ mov x1, #(0x2 << CLUSTERIDR_REV_BITS)
+ cmp x0, x1
+ csel x0, x2, x3, hs
+1:
+ ret
+endfunc check_errata_dsu_936184
+
+func errata_dsu_936184_wa
+ mov x20, x30
+ bl check_errata_dsu_936184
+ cbz x0, 1f
+
+ /* If erratum applies, we set a mask to a DSU control register */
+ mrs x0, CLUSTERACTLR_EL1
+ ldr x1, =DSU_ERRATA_936184_MASK
+ orr x0, x0, x1
+ msr CLUSTERACTLR_EL1, x0
+ isb
+1:
+ ret x20
+endfunc errata_dsu_936184_wa
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 456e3e5..40a8ac7 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -123,6 +123,11 @@
# only to r0p0 and r1p0 of the Ares cpu.
ERRATA_ARES_1043202 ?=1
+# Flag to apply DSU erratum 936184. This erratum applies to DSUs containing
+# the ACP interface and revision < r2p0. Applying the workaround results in
+# higher DSU power consumption on idle.
+ERRATA_DSU_936184 ?=0
+
# Process ERRATA_A53_826319 flag
$(eval $(call assert_boolean,ERRATA_A53_826319))
$(eval $(call add_define,ERRATA_A53_826319))
@@ -187,6 +192,10 @@
$(eval $(call assert_boolean,ERRATA_ARES_1043202))
$(eval $(call add_define,ERRATA_ARES_1043202))
+# Process ERRATA_DSU_936184 flag
+$(eval $(call assert_boolean,ERRATA_DSU_936184))
+$(eval $(call add_define,ERRATA_DSU_936184))
+
# Errata build flags
ifneq (${ERRATA_A53_843419},0)
TF_LDFLAGS_aarch64 += --fix-cortex-a53-843419