[PATCH v1] arm64: errata: Mitigate TLBI errata on NVIDIA Olympus CPU

[Shanker Donthineni <sdonthineni@nvidia.com>]

NVIDIA Olympus cores are affected by the TLBI completion issue tracked as
CVE-2025-10263. The existing ARM64_ERRATUM_4118414 handling already uses
ARM64_WORKAROUND_REPEAT_TLBI to issue an additional broadcast TLBI;DSB
sequence and ensure affected memory write effects are globally observed.

Add MIDR_NVIDIA_OLYMPUS to the repeat-TLBI match list so the same
mitigation is enabled on affected Olympus systems. Also document the
NVIDIA Olympus erratum in the arm64 silicon errata table and list it in
the Kconfig help text.

Signed-off-by: Shanker Donthineni <sdonthineni@nvidia.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
---
Note: This patch depends on the following series as a prerequisite:
https://lore.kernel.org/all/20260609101203.1512409-1-mark.rutland@arm.com/

 Documentation/arch/arm64/silicon-errata.rst | 2 ++
 arch/arm64/Kconfig                          | 3 ++-
 arch/arm64/kernel/cpu_errata.c              | 1 +
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst
index a01e916ede17..ad09bbb10da8 100644
--- a/Documentation/arch/arm64/silicon-errata.rst
+++ b/Documentation/arch/arm64/silicon-errata.rst
@@ -298,6 +298,8 @@ stable kernels.
 +----------------+-----------------+-----------------+-----------------------------+
 | NVIDIA         | Carmel Core     | N/A             | NVIDIA_CARMEL_CNP_ERRATUM   |
 +----------------+-----------------+-----------------+-----------------------------+
+| NVIDIA         | Olympus core    | T410-OLY-1029   | ARM64_ERRATUM_4118414       |
++----------------+-----------------+-----------------+-----------------------------+
 | NVIDIA         | T241 GICv3/4.x  | T241-FABRIC-4   | N/A                         |
 +----------------+-----------------+-----------------+-----------------------------+
 | NVIDIA         | T241 MPAM       | T241-MPAM-1     | N/A                         |
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 48233b54c482..c65cef81be86 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1155,7 +1155,7 @@ config ARM64_ERRATUM_4193714
 	  If unsure, say Y.
 
 config ARM64_ERRATUM_4118414
-	bool "Cortex-*/Neoverse-*/C1-*: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
+	bool "Cortex-*/Neoverse-*/C1-*/Olympus: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
 	default y
 	select ARM64_WORKAROUND_REPEAT_TLBI
 	help
@@ -1182,6 +1182,7 @@ config ARM64_ERRATUM_4118414
 	  * ARM Neoverse-V2 erratum 4193787
 	  * ARM Neoverse-V3 erratum 4193784
 	  * ARM Neoverse-V3AE erratum 4193784
+	  * NVIDIA Olympus erratum T410-OLY-1029
 
 	  On affected cores, some memory accesses might not be completed by
 	  broadcast TLB invalidation.
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index fe6fe5de495b..d597896b0f7f 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -364,6 +364,7 @@ static const struct arm64_cpu_capabilities arm64_repeat_tlbi_list[] = {
 			MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V2),
 			MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V3),
 			MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V3AE),
+			MIDR_ALL_VERSIONS(MIDR_NVIDIA_OLYMPUS),
 			{}
 		})),
 	},
-- 
2.43.0