linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Suzuki K Poulose <suzuki.poulose@arm.com>
To: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org, will.deacon@arm.com,
	catalin.marinas@arm.com, marc.zyngier@arm.com,
	mark.rutland@arm.com, james.morse@arm.com,
	ard.biesheuvel@linaro.org, andre.przywara@arm.com,
	Suzuki K Poulose <suzuki.poulose@arm.com>
Subject: [PATCH v3 1/9] arm64: Set the safe value for L1 icache policy
Date: Mon,  5 Sep 2016 10:58:21 +0100	[thread overview]
Message-ID: <1473069509-2317-2-git-send-email-suzuki.poulose@arm.com> (raw)
In-Reply-To: <1473069509-2317-1-git-send-email-suzuki.poulose@arm.com>

Right now we use 0 as the safe value for CTR_EL0:L1Ip, which is
not defined at the moment. The safer value for the L1Ip should be
the weakest of the policies, which happens to be AIVIVT. While at it,
fix the comment about safe_val.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 arch/arm64/include/asm/cpufeature.h | 2 +-
 arch/arm64/kernel/cpufeature.c      | 5 +++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index c07c5d1..df47969 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -63,7 +63,7 @@ struct arm64_ftr_bits {
 	enum ftr_type	type;
 	u8		shift;
 	u8		width;
-	s64		safe_val; /* safe value for discrete features */
+	s64		safe_val; /* safe value for FTR_EXACT features */
 };
 
 /*
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index c3d7ae4..4a19138d 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -147,9 +147,10 @@ static const struct arm64_ftr_bits ftr_ctr[] = {
 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1),	/* DminLine */
 	/*
 	 * Linux can handle differing I-cache policies. Userspace JITs will
-	 * make use of *minLine
+	 * make use of *minLine.
+	 * If we have differing I-cache policies, report it as the weakest - AIVIVT.
 	 */
-	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, 14, 2, 0),	/* L1Ip */
+	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_EXACT, 14, 2, ICACHE_POLICY_AIVIVT),	/* L1Ip */
 	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 4, 10, 0),	/* RAZ */
 	ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0),	/* IminLine */
 	ARM64_FTR_END,
-- 
2.7.4

  reply	other threads:[~2016-09-05  9:58 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-05  9:58 [PATCH v3 0/9] arm64: Work around for mismatched cache line size Suzuki K Poulose
2016-09-05  9:58 ` Suzuki K Poulose [this message]
2016-09-05  9:58 ` [PATCH v3 2/9] arm64: Use consistent naming for errata handling Suzuki K Poulose
2016-09-07 10:36   ` Andre Przywara
2016-09-05  9:58 ` [PATCH v3 3/9] arm64: Rearrange CPU errata workaround checks Suzuki K Poulose
2016-09-05  9:58 ` [PATCH v3 4/9] arm64: alternative: Disallow patching instructions using literals Suzuki K Poulose
2016-09-05  9:58 ` [PATCH v3 5/9] arm64: insn: Add helpers for adrp offsets Suzuki K Poulose
2016-09-05  9:58 ` [PATCH v3 6/9] arm64: alternative: Add support for patching adrp instructions Suzuki K Poulose
2016-09-05  9:58 ` [PATCH v3 7/9] arm64: Introduce raw_{d,i}cache_line_size Suzuki K Poulose
2016-09-05  9:58 ` [PATCH v3 8/9] arm64: Refactor sysinstr exception handling Suzuki K Poulose
2016-09-07  8:44   ` Will Deacon
2016-09-07 11:29   ` Andre Przywara
2016-09-05  9:58 ` [PATCH v3 9/9] arm64: Work around systems with mismatched cache line sizes Suzuki K Poulose
2016-09-05 10:10   ` Ard Biesheuvel
2016-09-05 10:24     ` Suzuki K Poulose

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1473069509-2317-2-git-send-email-suzuki.poulose@arm.com \
    --to=suzuki.poulose@arm.com \
    --cc=andre.przywara@arm.com \
    --cc=ard.biesheuvel@linaro.org \
    --cc=catalin.marinas@arm.com \
    --cc=james.morse@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marc.zyngier@arm.com \
    --cc=mark.rutland@arm.com \
    --cc=will.deacon@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).