arm64: Extend workaround for erratum 1024718 to all versions of Corte…

…x-A55

commit c0b15c2 upstream.

The erratum 1024718 affects Cortex-A55 r0p0 to r2p0. However
we apply the work around for r0p0 - r1p0. Unfortunately this
won't be fixed for the future revisions for the CPU. Thus
extend the work around for all versions of A55, to cover
for r2p0 and any future revisions.

Cc: stable@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20210203230057.3961239-1-suzuki.poulose@arm.com
[will: Update Kconfig help text]
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm64/Kconfig

@@ -489,7 +489,7 @@ config ARM64_ERRATUM_1024718
 	help
 	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
 
-	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
+	  Affected Cortex-A55 cores (all revisions) could cause incorrect
 	  update of the hardware dirty bit when the DBM/AP bits are updated
 	  without a break-before-make. The workaround is to disable the usage
 	  of hardware DBM locally on the affected cores. CPUs not affected by

arch/arm64/kernel/cpufeature.c

@@ -1092,7 +1092,7 @@ static bool cpu_has_broken_dbm(void)
 	/* List of CPUs which have broken DBM support. */
 	static const struct midr_range cpus[] = {
 #ifdef CONFIG_ARM64_ERRATUM_1024718
-		MIDR_RANGE(MIDR_CORTEX_A55, 0, 0, 1, 0),  // A55 r0p0 -r1p0
+		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
 #endif
 		{},
 	};