xen/arm: Enable workaround for Cortex-A53 erratum #1530924

All versions of Cortex-A53 cores are affected by the speculative
AT instruction erratum, as mentioned in the Cortex-A53 Revision r0
SDEN v21 documentation.

Enabled ARM64_WORKAROUND_AT_SPECULATE for all versions of Cortex-A53
cores, to avoid corrupting the TLB if performing a speculative AT
instruction during a guest context switch.

Signed-off-by: Andrei Cherechesu <[email protected]>
Acked-by: Julien Grall <[email protected]>

Author: AndreiCherechesu-NXP

docs/misc/arm/silicon-errata.txt

@@ -46,6 +46,7 @@ stable hypervisors.
 | ARM            | Cortex-A53      | #824069         | ARM64_ERRATUM_824069    |
 | ARM            | Cortex-A53      | #819472         | ARM64_ERRATUM_819472    |
 | ARM            | Cortex-A53      | #843419         | ARM64_ERRATUM_843419    |
+| ARM            | Cortex-A53      | #1530924        | N/A                     |
 | ARM            | Cortex-A55      | #1530923        | N/A                     |
 | ARM            | Cortex-A57      | #852523         | N/A                     |
 | ARM            | Cortex-A57      | #832075         | ARM64_ERRATUM_832075    |

xen/arch/arm/cpuerrata.c

@@ -683,6 +683,12 @@ static const struct arm_cpu_capabilities arm_errata[] = {
         .capability = ARM64_WORKAROUND_AT_SPECULATE,
         MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
     },
+    {
+        /* Cortex-A53 (All versions) */
+        .desc = "ARM erratum 1530924",
+        .capability = ARM64_WORKAROUND_AT_SPECULATE,
+        MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
+    },
     {},
 };