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+=======================================
+Silicon Errata and Software Workarounds
+=======================================
+
+Author: Will Deacon <will.deacon@arm.com>
+
+Date : 27 November 2015
+
+It is an unfortunate fact of life that hardware is often produced with
+so-called "errata", which can cause it to deviate from the architecture
+under specific circumstances. For hardware produced by ARM, these
+errata are broadly classified into the following categories:
+
+ ========== ========================================================
+ Category A A critical error without a viable workaround.
+ Category B A significant or critical error with an acceptable
+ workaround.
+ Category C A minor error that is not expected to occur under normal
+ operation.
+ ========== ========================================================
+
+For more information, consult one of the "Software Developers Errata
+Notice" documents available on infocenter.arm.com (registration
+required).
+
+As far as Linux is concerned, Category B errata may require some special
+treatment in the operating system. For example, avoiding a particular
+sequence of code, or configuring the processor in a particular way. A
+less common situation may require similar actions in order to declassify
+a Category A erratum into a Category C erratum. These are collectively
+known as "software workarounds" and are only required in the minority of
+cases (e.g. those cases that both require a non-secure workaround *and*
+can be triggered by Linux).
+
+For software workarounds that may adversely impact systems unaffected by
+the erratum in question, a Kconfig entry is added under "Kernel
+Features" -> "ARM errata workarounds via the alternatives framework".
+These are enabled by default and patched in at runtime when an affected
+CPU is detected. For less-intrusive workarounds, a Kconfig option is not
+available and the code is structured (preferably with a comment) in such
+a way that the erratum will not be hit.
+
+This approach can make it slightly onerous to determine exactly which
+errata are worked around in an arbitrary kernel source tree, so this
+file acts as a registry of software workarounds in the Linux Kernel and
+will be updated when new workarounds are committed and backported to
+stable kernels.
+
++----------------+-----------------+-----------------+-----------------------------+
+| Implementor | Component | Erratum ID | Kconfig |
++================+=================+=================+=============================+
+| Allwinner | A64/R18 | UNKNOWN1 | SUN50I_ERRATUM_UNKNOWN1 |
++----------------+-----------------+-----------------+-----------------------------+
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A53 | #826319 | ARM64_ERRATUM_826319 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A53 | #827319 | ARM64_ERRATUM_827319 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A53 | #824069 | ARM64_ERRATUM_824069 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A53 | #819472 | ARM64_ERRATUM_819472 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A53 | #845719 | ARM64_ERRATUM_845719 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A53 | #843419 | ARM64_ERRATUM_843419 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A57 | #832075 | ARM64_ERRATUM_832075 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A57 | #852523 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A57 | #834220 | ARM64_ERRATUM_834220 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A72 | #853709 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A73 | #858921 | ARM64_ERRATUM_858921 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A55 | #1024718 | ARM64_ERRATUM_1024718 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A76 | #1188873,1418040| ARM64_ERRATUM_1418040 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A76 | #1165522 | ARM64_ERRATUM_1165522 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A76 | #1286807 | ARM64_ERRATUM_1286807 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A76 | #1463225 | ARM64_ERRATUM_1463225 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | Neoverse-N1 | #1188873,1418040| ARM64_ERRATUM_1418040 |
++----------------+-----------------+-----------------+-----------------------------+
+| ARM | MMU-500 | #841119,826419 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
++----------------+-----------------+-----------------+-----------------------------+
+| Cavium | ThunderX ITS | #22375,24313 | CAVIUM_ERRATUM_22375 |
++----------------+-----------------+-----------------+-----------------------------+
+| Cavium | ThunderX ITS | #23144 | CAVIUM_ERRATUM_23144 |
++----------------+-----------------+-----------------+-----------------------------+
+| Cavium | ThunderX GICv3 | #23154 | CAVIUM_ERRATUM_23154 |
++----------------+-----------------+-----------------+-----------------------------+
+| Cavium | ThunderX Core | #27456 | CAVIUM_ERRATUM_27456 |
++----------------+-----------------+-----------------+-----------------------------+
+| Cavium | ThunderX Core | #30115 | CAVIUM_ERRATUM_30115 |
++----------------+-----------------+-----------------+-----------------------------+
+| Cavium | ThunderX SMMUv2 | #27704 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
+| Cavium | ThunderX2 SMMUv3| #74 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
+| Cavium | ThunderX2 SMMUv3| #126 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
++----------------+-----------------+-----------------+-----------------------------+
+| Freescale/NXP | LS2080A/LS1043A | A-008585 | FSL_ERRATUM_A008585 |
++----------------+-----------------+-----------------+-----------------------------+
++----------------+-----------------+-----------------+-----------------------------+
+| Hisilicon | Hip0{5,6,7} | #161010101 | HISILICON_ERRATUM_161010101 |
++----------------+-----------------+-----------------+-----------------------------+
+| Hisilicon | Hip0{6,7} | #161010701 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
+| Hisilicon | Hip07 | #161600802 | HISILICON_ERRATUM_161600802 |
++----------------+-----------------+-----------------+-----------------------------+
+| Hisilicon | Hip08 SMMU PMCG | #162001800 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
++----------------+-----------------+-----------------+-----------------------------+
+| Qualcomm Tech. | Kryo/Falkor v1 | E1003 | QCOM_FALKOR_ERRATUM_1003 |
++----------------+-----------------+-----------------+-----------------------------+
+| Qualcomm Tech. | Falkor v1 | E1009 | QCOM_FALKOR_ERRATUM_1009 |
++----------------+-----------------+-----------------+-----------------------------+
+| Qualcomm Tech. | QDF2400 ITS | E0065 | QCOM_QDF2400_ERRATUM_0065 |
++----------------+-----------------+-----------------+-----------------------------+
+| Qualcomm Tech. | Falkor v{1,2} | E1041 | QCOM_FALKOR_ERRATUM_1041 |
++----------------+-----------------+-----------------+-----------------------------+
++----------------+-----------------+-----------------+-----------------------------+
+| Fujitsu | A64FX | E#010001 | FUJITSU_ERRATUM_010001 |
++----------------+-----------------+-----------------+-----------------------------+