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arm64: cpufeature: Fix CTR_EL0 field definitions

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Our field definitions for CTR_EL0 suffer from a number of problems:

  - The IDC and DIC fields are missing, which causes us to enable CTR
    trapping on CPUs with either of these returning non-zero values.

  - The ERG is FTR_LOWER_SAFE, whereas it should be treated like CWG as
    FTR_HIGHER_SAFE so that applications can use it to avoid false sharing.

  - [nit] A RES1 field is described as "RAO"

This patch updates the CTR_EL0 field definitions to fix these issues.

Cc: <stable@vger.kernel.org>
Cc: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Will Deacon 2018-02-19 14:41:44 +00:00 committed by Catalin Marinas
parent 9085b34d0e
commit be68a8aaf9
1 changed files with 4 additions and 2 deletions
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6
arch/arm64/kernel/cpufeature.c
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@ -199,9 +199,11 @@ static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
};
static const struct arm64_ftr_bits ftr_ctr[] = {
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RAO */
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 29, 1, 1), /* DIC */
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 28, 1, 1), /* IDC */
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_SAFE, 24, 4, 0), /* CWG */
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0), /* ERG */
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_SAFE, 20, 4, 0), /* ERG */
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1), /* DminLine */
/*
* Linux can handle differing I-cache policies. Userspace JITs will