arm64: fix midr range for Cortex-A57 erratum 832075
authorBo Yan <byan@nvidia.com>
Tue, 31 Mar 2015 20:30:48 +0000 (21:30 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 6 May 2015 20:01:56 +0000 (22:01 +0200)
commitd5bfa1792f39c34d814a53d36c40d82fc8fd345f
tree9e3598a66124da23ea588f4a9b04734a10bf28c0
parentf885c032f9d8064597c958a6a6816740a671e091
arm64: fix midr range for Cortex-A57 erratum 832075

commit 6d1966dfd6e0ad2f8aa4b664ae1a62e33abe1998 upstream.

Register MIDR_EL1 is masked to get variant and revision fields, then
compared against midr_range_min and midr_range_max when checking
whether CPU is affected by any particular erratum. However, variant
and revision fields in MIDR_EL1 are separated by 16 bits, so the min
and max of midr range should be constructed accordingly, otherwise
the patch will not be applied when variant field is non-0.

Acked-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Bo Yan <byan@nvidia.com>
[will: use MIDR_VARIANT_SHIFT to construct upper bound]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/arm64/kernel/cpu_errata.c