Cortex-A72: Implement workaround for erratum 859971
Erratum 855971 applies to revision r0p3 or earlier Cortex-A72 CPUs. The
recommended workaround is to disable instruction prefetch.
Change-Id: I7fde74ee2a8a23b2a8a1891b260f0eb909fad4bf
Signed-off-by: Eleanor Bonnici <Eleanor.bonnici@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
diff --git a/docs/cpu-specific-build-macros.rst b/docs/cpu-specific-build-macros.rst
index 6b154f0..f74b459 100644
--- a/docs/cpu-specific-build-macros.rst
+++ b/docs/cpu-specific-build-macros.rst
@@ -21,6 +21,7 @@
- `Cortex-A53 MPCore Software Developers Errata Notice`_
- `Cortex-A57 MPCore Software Developers Errata Notice`_
+- `Cortex-A72 MPCore Software Developers Errata Notice`_
The errata workarounds are implemented for a particular revision or a set of
processor revisions. This is checked by the reset handler at runtime. Each
@@ -102,6 +103,12 @@
- ``ERRATA_A57_859972``: This applies errata 859972 workaround to Cortex-A57
CPU. This needs to be enabled only for revision <= r1p3 of the CPU.
+
+For Cortex-A72, 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.
+
CPU Specific optimizations
--------------------------
@@ -137,5 +144,6 @@
.. _Cortex-A53 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm048406/Cortex_A53_MPCore_Software_Developers_Errata_Notice.pdf
.. _Cortex-A57 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm049219/cortex_a57_mpcore_software_developers_errata_notice.pdf
+.. _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
diff --git a/include/lib/cpus/aarch32/cortex_a72.h b/include/lib/cpus/aarch32/cortex_a72.h
index 306253d..f7da1f0 100644
--- a/include/lib/cpus/aarch32/cortex_a72.h
+++ b/include/lib/cpus/aarch32/cortex_a72.h
@@ -34,6 +34,7 @@
#define CORTEX_A72_CPUACTLR_DISABLE_L1_DCACHE_HW_PFTCH (ULL(1) << 56)
#define CORTEX_A72_CPUACTLR_NO_ALLOC_WBWA (ULL(1) << 49)
#define CORTEX_A72_CPUACTLR_DCC_AS_DCCI (ULL(1) << 44)
+#define CORTEX_A72_CPUACTLR_DIS_INSTR_PREFETCH (ULL(1) << 32)
/*******************************************************************************
* L2 Control register specific definitions.
diff --git a/include/lib/cpus/aarch64/cortex_a72.h b/include/lib/cpus/aarch64/cortex_a72.h
index aed714c..6fbb707 100644
--- a/include/lib/cpus/aarch64/cortex_a72.h
+++ b/include/lib/cpus/aarch64/cortex_a72.h
@@ -34,6 +34,7 @@
#define CORTEX_A72_CPUACTLR_EL1_DISABLE_L1_DCACHE_HW_PFTCH (ULL(1) << 56)
#define CORTEX_A72_CPUACTLR_EL1_NO_ALLOC_WBWA (ULL(1) << 49)
#define CORTEX_A72_CPUACTLR_EL1_DCC_AS_DCCI (ULL(1) << 44)
+#define CORTEX_A72_CPUACTLR_EL1_DIS_INSTR_PREFETCH (ULL(1) << 32)
/*******************************************************************************
* L2 Control register specific definitions.
diff --git a/lib/cpus/aarch32/cortex_a72.S b/lib/cpus/aarch32/cortex_a72.S
index d164cfd..69cc2ea 100644
--- a/lib/cpus/aarch32/cortex_a72.S
+++ b/lib/cpus/aarch32/cortex_a72.S
@@ -61,11 +61,46 @@
bx lr
endfunc cortex_a72_disable_ext_debug
+ /* ---------------------------------------------------
+ * Errata Workaround for Cortex A72 Errata #859971.
+ * This applies only to revision <= r0p3 of Cortex A72.
+ * Inputs:
+ * r0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: r0-r3
+ * ---------------------------------------------------
+ */
+func errata_a72_859971_wa
+ mov r2,lr
+ bl check_errata_859971
+ mov lr, r2
+ cmp r0, #ERRATA_NOT_APPLIES
+ beq 1f
+ ldcopr16 r0, r1, CORTEX_A72_CPUACTLR
+ orr64_imm r1, r1, CORTEX_A72_CPUACTLR_DIS_INSTR_PREFETCH
+ stcopr16 r0, r1, CORTEX_A72_CPUACTLR
+1:
+ bx lr
+endfunc errata_a72_859971_wa
+
+func check_errata_859971
+ mov r1, #0x03
+ b cpu_rev_var_ls
+endfunc check_errata_859971
+
+
/* -------------------------------------------------
* The CPU Ops reset function for Cortex-A72.
* -------------------------------------------------
*/
func cortex_a72_reset_func
+ mov r5, lr
+ bl cpu_get_rev_var
+ mov r4, r0
+
+#if ERRATA_A72_859971
+ mov r0, r4
+ bl errata_a72_859971_wa
+#endif
/* ---------------------------------------------
* Enable the SMP bit.
* ---------------------------------------------
@@ -186,6 +221,27 @@
b cortex_a72_disable_ext_debug
endfunc cortex_a72_cluster_pwr_dwn
+#if REPORT_ERRATA
+/*
+ * Errata printing function for Cortex A72. Must follow AAPCS.
+ */
+func cortex_a72_errata_report
+ push {r12, lr}
+
+ bl cpu_get_rev_var
+ mov r4, r0
+
+ /*
+ * Report all errata. The revision-variant information is passed to
+ * checking functions of each errata.
+ */
+ report_errata ERRATA_A72_859971, cortex_a72, 859971
+
+ pop {r12, lr}
+ bx lr
+endfunc cortex_a72_errata_report
+#endif
+
declare_cpu_ops cortex_a72, CORTEX_A72_MIDR, \
cortex_a72_reset_func, \
cortex_a72_core_pwr_dwn, \
diff --git a/lib/cpus/aarch64/cortex_a72.S b/lib/cpus/aarch64/cortex_a72.S
index 5de2bf0..b034125 100644
--- a/lib/cpus/aarch64/cortex_a72.S
+++ b/lib/cpus/aarch64/cortex_a72.S
@@ -73,20 +73,52 @@
ret
endfunc cortex_a72_disable_ext_debug
+ /* --------------------------------------------------
+ * Errata Workaround for Cortex A72 Errata #859971.
+ * This applies only to revision <= r0p3 of Cortex A72.
+ * Inputs:
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber:
+ * --------------------------------------------------
+ */
+func errata_a72_859971_wa
+ mov x17,x30
+ bl check_errata_859971
+ cbz x0, 1f
+ mrs x1, CORTEX_A72_CPUACTLR_EL1
+ orr x1, x1, #CORTEX_A72_CPUACTLR_EL1_DIS_INSTR_PREFETCH
+ msr CORTEX_A72_CPUACTLR_EL1, x1
+1:
+ ret x17
+endfunc errata_a72_859971_wa
+
+func check_errata_859971
+ mov x1, #0x03
+ b cpu_rev_var_ls
+endfunc check_errata_859971
+
/* -------------------------------------------------
* The CPU Ops reset function for Cortex-A72.
* -------------------------------------------------
*/
func cortex_a72_reset_func
+ mov x19, x30
+ bl cpu_get_rev_var
+ mov x18, x0
+
+#if ERRATA_A72_859971
+ mov x0, x18
+ bl errata_a72_859971_wa
+#endif
/* ---------------------------------------------
- * As a bare minimum enable the SMP bit.
+ * Enable the SMP bit.
* ---------------------------------------------
*/
mrs x0, CORTEX_A72_ECTLR_EL1
orr x0, x0, #CORTEX_A72_ECTLR_SMP_BIT
msr CORTEX_A72_ECTLR_EL1, x0
isb
- ret
+ ret x19
endfunc cortex_a72_reset_func
/* ----------------------------------------------------
@@ -196,6 +228,27 @@
b cortex_a72_disable_ext_debug
endfunc cortex_a72_cluster_pwr_dwn
+#if REPORT_ERRATA
+/*
+ * Errata printing function for Cortex A72. Must follow AAPCS.
+ */
+func cortex_a72_errata_report
+ stp x8, x30, [sp, #-16]!
+
+ bl cpu_get_rev_var
+ mov x8, x0
+
+ /*
+ * Report all errata. The revision-variant information is passed to
+ * checking functions of each errata.
+ */
+ report_errata ERRATA_A72_859971, cortex_a72, 859971
+
+ ldp x8, x30, [sp], #16
+ ret
+endfunc cortex_a72_errata_report
+#endif
+
/* ---------------------------------------------
* This function provides cortex_a72 specific
* register information for crash reporting.
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 198a32e..31adfb4 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -95,6 +95,10 @@
# only to revision <= r1p3 of the Cortex A57 cpu.
ERRATA_A57_859972 ?=0
+# Flag to apply erratum 855971 workaround during reset. This erratum applies
+# only to revision <= r0p3 of the Cortex A72 cpu.
+ERRATA_A72_859971 ?=0
+
# Process ERRATA_A53_826319 flag
$(eval $(call assert_boolean,ERRATA_A53_826319))
$(eval $(call add_define,ERRATA_A53_826319))
@@ -151,6 +155,10 @@
$(eval $(call assert_boolean,ERRATA_A57_859972))
$(eval $(call add_define,ERRATA_A57_859972))
+# Process ERRATA_A72_859971 flag
+$(eval $(call assert_boolean,ERRATA_A72_859971))
+$(eval $(call add_define,ERRATA_A72_859971))
+
# Errata build flags
ifneq (${ERRATA_A53_843419},0)
TF_LDFLAGS_aarch64 += --fix-cortex-a53-843419
