Merge changes I36e4d672,I47610cee into integration

* changes:
  Workaround for Cortex N1 erratum 1946160
  Workaround for Cortex A78 erratum 1951500
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 09aa301..7c142d1 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -268,6 +268,10 @@
 -  ``ERRATA_A78_1941498``: This applies errata 1941498 workaround to Cortex-A78
    CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the CPU.
 
+-  ``ERRATA_A78_1951500``: This applies errata 1951500 workaround to Cortex-A78
+   CPU. This needs to be enabled for revisions r1p0 and r1p1, r0p0 has the same
+   issue but there is no workaround for that revision.
+
 For Neoverse N1, the following errata build flags are defined :
 
 -  ``ERRATA_N1_1073348``: This applies errata 1073348 workaround to Neoverse-N1
@@ -306,6 +310,10 @@
 -  ``ERRATA_N1_1868343``: This applies errata 1868343 workaround to Neoverse-N1
    CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
 
+-  ``ERRATA_N1_1946160``: This applies errata 1946160 workaround to Neoverse-N1
+   CPU. This needs to be enabled for revisions r3p0, r3p1, r4p0, and r4p1, for
+   revisions r0p0, r1p0, and r2p0 there is no workaround.
+
 DSU Errata Workarounds
 ----------------------
 
diff --git a/include/lib/cpus/errata_report.h b/include/lib/cpus/errata_report.h
index 7cac77e..efdedf0 100644
--- a/include/lib/cpus/errata_report.h
+++ b/include/lib/cpus/errata_report.h
@@ -30,4 +30,7 @@
 #define ERRATA_APPLIES		1
 #define ERRATA_MISSING		2
 
+/* Macro to get CPU revision code for checking errata version compatibility. */
+#define CPU_REV(r, p)		((r << 4) | p)
+
 #endif /* ERRATA_REPORT_H */
diff --git a/lib/cpus/aarch64/cortex_a78.S b/lib/cpus/aarch64/cortex_a78.S
index ef760ed..f61726b 100644
--- a/lib/cpus/aarch64/cortex_a78.S
+++ b/lib/cpus/aarch64/cortex_a78.S
@@ -72,6 +72,60 @@
 	b	cpu_rev_var_ls
 endfunc check_errata_1941498
 
+	/* --------------------------------------------------
+	 * Errata Workaround for A78 Erratum 1951500.
+	 * This applies to revisions r1p0 and r1p1 of A78.
+	 * The issue also exists in r0p0 but there is no fix
+	 * in that revision.
+	 * Inputs:
+	 * x0: variant[4:7] and revision[0:3] of current cpu.
+	 * Shall clobber: x0-x17
+	 * --------------------------------------------------
+	 */
+func errata_a78_1951500_wa
+	/* Compare x0 against revisions r1p0 - r1p1 */
+	mov	x17, x30
+	bl	check_errata_1951500
+	cbz	x0, 1f
+
+	msr	S3_6_c15_c8_0, xzr
+	ldr	x0, =0x10E3900002
+	msr	S3_6_c15_c8_2, x0
+	ldr	x0, =0x10FFF00083
+	msr	S3_6_c15_c8_3, x0
+	ldr	x0, =0x2001003FF
+	msr	S3_6_c15_c8_1, x0
+
+	mov	x0, #1
+	msr	S3_6_c15_c8_0, x0
+	ldr	x0, =0x10E3800082
+	msr	S3_6_c15_c8_2, x0
+	ldr	x0, =0x10FFF00083
+	msr	S3_6_c15_c8_3, x0
+	ldr	x0, =0x2001003FF
+	msr	S3_6_c15_c8_1, x0
+
+	mov	x0, #2
+	msr	S3_6_c15_c8_0, x0
+	ldr	x0, =0x10E3800200
+	msr	S3_6_c15_c8_2, x0
+	ldr	x0, =0x10FFF003E0
+	msr	S3_6_c15_c8_3, x0
+	ldr	x0, =0x2001003FF
+	msr	S3_6_c15_c8_1, x0
+
+	isb
+1:
+	ret	x17
+endfunc errata_a78_1951500_wa
+
+func check_errata_1951500
+	/* Applies to revisions r1p0 and r1p1. */
+	mov	x1, #CPU_REV(1, 0)
+	mov	x2, #CPU_REV(1, 1)
+	b	cpu_rev_var_range
+endfunc check_errata_1951500
+
 	/* -------------------------------------------------
 	 * The CPU Ops reset function for Cortex-A78
 	 * -------------------------------------------------
@@ -91,6 +145,11 @@
 	bl	errata_a78_1941498_wa
 #endif
 
+#if ERRATA_A78_1951500
+	mov	x0, x18
+	bl	errata_a78_1951500_wa
+#endif
+
 #if ENABLE_AMU
 	/* Make sure accesses from EL0/EL1 and EL2 are not trapped to EL3 */
 	mrs	x0, actlr_el3
@@ -147,6 +206,7 @@
 	 */
 	report_errata ERRATA_A78_1688305, cortex_a78, 1688305
 	report_errata ERRATA_A78_1941498, cortex_a78, 1941498
+	report_errata ERRATA_A78_1951500, cortex_a78, 1951500
 
 	ldp	x8, x30, [sp], #16
 	ret
diff --git a/lib/cpus/aarch64/neoverse_n1.S b/lib/cpus/aarch64/neoverse_n1.S
index 96891be..9c97cf6 100644
--- a/lib/cpus/aarch64/neoverse_n1.S
+++ b/lib/cpus/aarch64/neoverse_n1.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2020, Arm Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2021, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -407,6 +407,63 @@
 	b	cpu_rev_var_ls
 endfunc check_errata_1868343
 
+	/* --------------------------------------------------
+	 * Errata Workaround for Neoverse N1 Errata #1946160.
+	 * This applies to revisions r3p0, r3p1, r4p0, and
+	 * r4p1 of Neoverse N1. It also exists in r0p0, r1p0,
+	 * and r2p0 but there is no fix in these revisions.
+	 * Inputs:
+	 * x0: variant[4:7] and revision[0:3] of current cpu.
+	 * Shall clobber: x0-x17
+	 * --------------------------------------------------
+	 */
+func errata_n1_1946160_wa
+	/*
+	 * Compare x0 against r3p0 - r4p1
+	 */
+	mov	x17, x30
+	bl	check_errata_1946160
+	cbz	x0, 1f
+
+	mov	x0, #3
+	msr	S3_6_C15_C8_0, x0
+	ldr	x0, =0x10E3900002
+	msr	S3_6_C15_C8_2, x0
+	ldr	x0, =0x10FFF00083
+	msr	S3_6_C15_C8_3, x0
+	ldr	x0, =0x2001003FF
+	msr	S3_6_C15_C8_1, x0
+
+	mov	x0, #4
+	msr	S3_6_C15_C8_0, x0
+	ldr	x0, =0x10E3800082
+	msr	S3_6_C15_C8_2, x0
+	ldr	x0, =0x10FFF00083
+	msr	S3_6_C15_C8_3, x0
+	ldr	x0, =0x2001003FF
+	msr	S3_6_C15_C8_1, x0
+
+	mov	x0, #5
+	msr	S3_6_C15_C8_0, x0
+	ldr	x0, =0x10E3800200
+	msr	S3_6_C15_C8_2, x0
+	ldr	x0, =0x10FFF003E0
+	msr	S3_6_C15_C8_3, x0
+	ldr	x0, =0x2001003FF
+	msr	S3_6_C15_C8_1, x0
+
+	isb
+1:
+	ret	x17
+endfunc errata_n1_1946160_wa
+
+func check_errata_1946160
+	/* Applies to r3p0 - r4p1. */
+	mov	x1, #0x30
+	mov	x2, #0x41
+	b	cpu_rev_var_range
+endfunc check_errata_1946160
+
 func neoverse_n1_reset_func
 	mov	x19, x30
 
@@ -486,6 +543,11 @@
 	bl	errata_n1_1868343_wa
 #endif
 
+#if ERRATA_N1_1946160
+	mov	x0, x18
+	bl	errata_n1_1946160_wa
+#endif
+
 #if ENABLE_AMU
 	/* Make sure accesses from EL0/EL1 and EL2 are not trapped to EL3 */
 	mrs	x0, actlr_el3
@@ -560,6 +622,7 @@
 	report_errata ERRATA_N1_1315703, neoverse_n1, 1315703
 	report_errata ERRATA_N1_1542419, neoverse_n1, 1542419
 	report_errata ERRATA_N1_1868343, neoverse_n1, 1868343
+	report_errata ERRATA_N1_1946160, neoverse_n1, 1946160
 	report_errata ERRATA_DSU_936184, neoverse_n1, dsu_936184
 
 	ldp	x8, x30, [sp], #16
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index b7dec0b..64a4b4d 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -298,6 +298,11 @@
 # to revisions r0p0, r1p0, and r1p1 of the A78 cpu.
 ERRATA_A78_1941498	?=0
 
+# Flag to apply erratum 1951500 workaround during reset. This erratum applies
+# to revisions r1p0 and r1p1 of the A78 cpu.  The issue is present in r0p0 as
+# well but there is no workaround for that revision.
+ERRATA_A78_1951500	?=0
+
 # Flag to apply T32 CLREX workaround during reset. This erratum applies
 # only to r0p0 and r1p0 of the Neoverse N1 cpu.
 ERRATA_N1_1043202	?=0
@@ -350,6 +355,11 @@
 # to revision <= r4p0 of the Neoverse N1 cpu.
 ERRATA_N1_1868343	?=0
 
+# Flag to apply erratum 1946160 workaround during reset. This erratum applies
+# to revisions r3p0, r3p1, r4p0, and r4p1 of the Neoverse N1 cpu.  The issue
+# exists in revisions r0p0, r1p0, and r2p0 as well but there is no workaround.
+ERRATA_N1_1946160	?=0
+
 # Flag to apply DSU erratum 798953. This erratum applies to DSUs revision r0p0.
 # Applying the workaround results in higher DSU power consumption on idle.
 ERRATA_DSU_798953	?=0
@@ -583,6 +593,10 @@
 $(eval $(call assert_boolean,ERRATA_A78_1941498))
 $(eval $(call add_define,ERRATA_A78_1941498))
 
+# Process ERRATA_A78_1951500 flag
+$(eval $(call assert_boolean,ERRATA_A78_1951500))
+$(eval $(call add_define,ERRATA_A78_1951500))
+
 # Process ERRATA_N1_1043202 flag
 $(eval $(call assert_boolean,ERRATA_N1_1043202))
 $(eval $(call add_define,ERRATA_N1_1043202))
@@ -635,6 +649,10 @@
 $(eval $(call assert_boolean,ERRATA_N1_1868343))
 $(eval $(call add_define,ERRATA_N1_1868343))
 
+# Process ERRATA_N1_1946160 flag
+$(eval $(call assert_boolean,ERRATA_N1_1946160))
+$(eval $(call add_define,ERRATA_N1_1946160))
+
 # Process ERRATA_DSU_798953 flag
 $(eval $(call assert_boolean,ERRATA_DSU_798953))
 $(eval $(call add_define,ERRATA_DSU_798953))