From: Zhenyu Ye <yezhenyu2@huawei.com>
To: <peterz@infradead.org>, <mark.rutland@arm.com>, <will@kernel.org>,
<catalin.marinas@arm.com>, <aneesh.kumar@linux.ibm.com>,
<akpm@linux-foundation.org>, <npiggin@gmail.com>, <arnd@arndb.de>,
<rostedt@goodmis.org>, <maz@kernel.org>, <suzuki.poulose@arm.com>,
<tglx@linutronix.de>, <yuzhao@google.com>, <Dave.Martin@arm.com>,
<steven.price@arm.com>, <broonie@kernel.org>,
<guohanjun@huawei.com>, <corbet@lwn.net>, <vgupta@synopsys.com>,
<tony.luck@intel.com>
Cc: linux-arch@vger.kernel.org, yezhenyu2@huawei.com,
linux-kernel@vger.kernel.org, xiexiangyou@huawei.com,
zhangshaokun@hisilicon.com, linux-mm@kvack.org, arm@kernel.org,
prime.zeng@hisilicon.com, kuhn.chenqun@huawei.com,
linux-arm-kernel@lists.infradead.org
Subject: [RFC PATCH v5 1/8] arm64: Detect the ARMv8.4 TTL feature
Date: Tue, 31 Mar 2020 22:29:20 +0800 [thread overview]
Message-ID: <20200331142927.1237-2-yezhenyu2@huawei.com> (raw)
In-Reply-To: <20200331142927.1237-1-yezhenyu2@huawei.com>
From: Marc Zyngier <maz@kernel.org>
In order to reduce the cost of TLB invalidation, the ARMv8.4 TTL
feature allows TLBs to be issued with a level allowing for quicker
invalidation.
Let's detect the feature for now. Further patches will implement
its actual usage.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Zhenyu Ye <yezhenyu2@huawei.com>
---
arch/arm64/include/asm/cpucaps.h | 3 ++-
arch/arm64/include/asm/sysreg.h | 1 +
arch/arm64/kernel/cpufeature.c | 11 +++++++++++
3 files changed, 14 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h
index 865e0253fc1e..8b3b4dd612b3 100644
--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -58,7 +58,8 @@
#define ARM64_WORKAROUND_SPECULATIVE_AT_NVHE 48
#define ARM64_HAS_E0PD 49
#define ARM64_HAS_RNG 50
+#define ARM64_HAS_ARMv8_4_TTL 51
-#define ARM64_NCAPS 51
+#define ARM64_NCAPS 52
#endif /* __ASM_CPUCAPS_H */
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index b91570ff9db1..a28b76f32ba7 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -685,6 +685,7 @@
/* id_aa64mmfr2 */
#define ID_AA64MMFR2_E0PD_SHIFT 60
+#define ID_AA64MMFR2_TTL_SHIFT 48
#define ID_AA64MMFR2_FWB_SHIFT 40
#define ID_AA64MMFR2_AT_SHIFT 32
#define ID_AA64MMFR2_LVA_SHIFT 16
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 0b6715625cf6..cbe46ad2900a 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -241,6 +241,7 @@ static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
@@ -1523,6 +1524,16 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
.matches = has_cpuid_feature,
.cpu_enable = cpu_has_fwb,
},
+ {
+ .desc = "ARMv8.4 Translation Table Level",
+ .type = ARM64_CPUCAP_SYSTEM_FEATURE,
+ .capability = ARM64_HAS_ARMv8_4_TTL,
+ .sys_reg = SYS_ID_AA64MMFR2_EL1,
+ .sign = FTR_UNSIGNED,
+ .field_pos = ID_AA64MMFR2_TTL_SHIFT,
+ .min_field_value = 1,
+ .matches = has_cpuid_feature,
+ },
#ifdef CONFIG_ARM64_HW_AFDBM
{
/*
--
2.19.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-03-31 16:14 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-31 14:29 [RFC PATCH v5 0/8] arm64: tlb: add support for TTL feature Zhenyu Ye
2020-03-31 14:29 ` Zhenyu Ye [this message]
2020-03-31 14:29 ` [RFC PATCH v5 2/8] arm64: Add level-hinted TLB invalidation helper Zhenyu Ye
2020-03-31 14:29 ` [RFC PATCH v5 3/8] arm64: Add tlbi_user_level " Zhenyu Ye
2020-03-31 14:29 ` [RFC PATCH v5 4/8] mm: tlb: Pass struct mmu_gather to flush_pmd_tlb_range Zhenyu Ye
2020-03-31 15:13 ` Peter Zijlstra
2020-04-01 8:51 ` Zhenyu Ye
2020-04-01 12:20 ` Peter Zijlstra
2020-04-02 11:24 ` Zhenyu Ye
2020-04-02 16:38 ` Peter Zijlstra
2020-04-03 5:14 ` Zhenyu Ye
2020-04-08 9:00 ` Zhenyu Ye
2020-03-31 14:29 ` [RFC PATCH v5 5/8] mm: tlb: Pass struct mmu_gather to flush_pud_tlb_range Zhenyu Ye
2020-03-31 14:29 ` [RFC PATCH v5 6/8] mm: tlb: Pass struct mmu_gather to flush_hugetlb_tlb_range Zhenyu Ye
2020-03-31 14:29 ` [RFC PATCH v5 7/8] mm: tlb: Pass struct mmu_gather to flush_tlb_range Zhenyu Ye
2020-03-31 14:29 ` [RFC PATCH v5 8/8] arm64: tlb: Set the TTL field in flush_tlb_range Zhenyu Ye
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=20200331142927.1237-2-yezhenyu2@huawei.com \
--to=yezhenyu2@huawei.com \
--cc=Dave.Martin@arm.com \
--cc=akpm@linux-foundation.org \
--cc=aneesh.kumar@linux.ibm.com \
--cc=arm@kernel.org \
--cc=arnd@arndb.de \
--cc=broonie@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=corbet@lwn.net \
--cc=guohanjun@huawei.com \
--cc=kuhn.chenqun@huawei.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mark.rutland@arm.com \
--cc=maz@kernel.org \
--cc=npiggin@gmail.com \
--cc=peterz@infradead.org \
--cc=prime.zeng@hisilicon.com \
--cc=rostedt@goodmis.org \
--cc=steven.price@arm.com \
--cc=suzuki.poulose@arm.com \
--cc=tglx@linutronix.de \
--cc=tony.luck@intel.com \
--cc=vgupta@synopsys.com \
--cc=will@kernel.org \
--cc=xiexiangyou@huawei.com \
--cc=yuzhao@google.com \
--cc=zhangshaokun@hisilicon.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).