arm64: Apply ARM64_ERRATUM_1188873 to Neoverse-N1

Neoverse-N1 is also affected by ARM64_ERRATUM_1188873, so let's
add it to the list of affected CPUs.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
[will: Update silicon-errata.txt]
Signed-off-by: Will Deacon <will.deacon@arm.com>

Documentation/arm64/silicon-errata.txt

@@ -61,6 +61,7 @@ stable kernels.
 | ARM            | Cortex-A76      | #1188873        | ARM64_ERRATUM_1188873       |
 | ARM            | Cortex-A76      | #1165522        | ARM64_ERRATUM_1165522       |
 | ARM            | Cortex-A76      | #1286807        | ARM64_ERRATUM_1286807       |
+| ARM            | Neoverse-N1     | #1188873        | ARM64_ERRATUM_1188873       |
 | ARM            | MMU-500         | #841119,#826419 | N/A                         |
 |                |                 |                 |                             |
 | Cavium         | ThunderX ITS    | #22375, #24313  | CAVIUM_ERRATUM_22375        |

arch/arm64/Kconfig

@@ -475,16 +475,17 @@ config ARM64_ERRATUM_1024718
 	  If unsure, say Y.
 
 config ARM64_ERRATUM_1188873
-	bool "Cortex-A76: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
+	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
 	default y
 	depends on COMPAT
 	select ARM_ARCH_TIMER_OOL_WORKAROUND
 	help
-	  This option adds work arounds for ARM Cortex-A76 erratum 1188873
+	  This option adds work arounds for ARM Cortex-A76/Neoverse-N1
+	  erratum 1188873
 
-	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could cause
-	  register corruption when accessing the timer registers from
-	  AArch32 userspace.
+	  Affected Cortex-A76/Neoverse-N1 cores (r0p0, r1p0, r2p0) could
+	  cause register corruption when accessing the timer registers
+	  from AArch32 userspace.
 
 	  If unsure, say Y.
 

arch/arm64/kernel/cpu_errata.c

@@ -603,6 +603,16 @@ static const struct midr_range workaround_clean_cache[] = {
 };
 #endif
 
+#ifdef CONFIG_ARM64_ERRATUM_1188873
+static const struct midr_range erratum_1188873_list[] = {
+	/* Cortex-A76 r0p0 to r2p0 */
+	MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 2, 0),
+	/* Neoverse-N1 r0p0 to r2p0 */
+	MIDR_RANGE(MIDR_NEOVERSE_N1, 0, 0, 2, 0),
+	{},
+};
+#endif
+
 const struct arm64_cpu_capabilities arm64_errata[] = {
 #ifdef CONFIG_ARM64_WORKAROUND_CLEAN_CACHE
 	{
@@ -725,10 +735,9 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
 #endif
 #ifdef CONFIG_ARM64_ERRATUM_1188873
 	{
-		/* Cortex-A76 r0p0 to r2p0 */
 		.desc = "ARM erratum 1188873",
 		.capability = ARM64_WORKAROUND_1188873,
-		ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 2, 0),
+		ERRATA_MIDR_RANGE_LIST(erratum_1188873_list),
 	},
 #endif
 #ifdef CONFIG_ARM64_ERRATUM_1165522