From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean-Philippe Brucker Subject: [PATCH v2 26/40] iommu/arm-smmu-v3: Enable broadcast TLB maintenance Date: Fri, 11 May 2018 20:06:27 +0100 Message-ID: <20180511190641.23008-27-jean-philippe.brucker@arm.com> References: <20180511190641.23008-1-jean-philippe.brucker@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180511190641.23008-1-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-acpi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org Cc: xuzaibo-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, okaya-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, ashok.raj-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, bharatku-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org, rfranz-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org, rgummal-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org, ilias.apalodimas-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, christian.koenig-5C7GfCeVMHo@public.gmane.org List-Id: iommu@lists.linux-foundation.org The SMMUv3 can handle invalidation targeted at TLB entries with shared ASIDs. If the implementation supports broadcast TLB maintenance, enable it and keep track of it in a feature bit. The SMMU will then be affected by inner-shareable TLB invalidations from other agents. A major side-effect of this change is that stage-2 translation contexts are now affected by all invalidations by VMID. VMIDs are all shared and the only ways to prevent over-invalidation, since the stage-2 page tables are not shared between CPU and SMMU, are to either disable BTM or allocate different VMIDs. This patch does not address the problem. Signed-off-by: Jean-Philippe Brucker --- drivers/iommu/arm-smmu-v3.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 280a5d9be839..073cba33ae6c 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -64,6 +64,7 @@ #define IDR0_ASID16 (1 << 12) #define IDR0_ATS (1 << 10) #define IDR0_HYP (1 << 9) +#define IDR0_BTM (1 << 5) #define IDR0_COHACC (1 << 4) #define IDR0_TTF GENMASK(3, 2) #define IDR0_TTF_AARCH64 2 @@ -523,6 +524,7 @@ struct arm_smmu_device { #define ARM_SMMU_FEAT_STALL_FORCE (1 << 13) #define ARM_SMMU_FEAT_VAX (1 << 14) #define ARM_SMMU_FEAT_E2H (1 << 15) +#define ARM_SMMU_FEAT_BTM (1 << 16) u32 features; #define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0) @@ -2459,11 +2461,14 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass) writel_relaxed(reg, smmu->base + ARM_SMMU_CR1); /* CR2 (random crap) */ - reg = CR2_PTM | CR2_RECINVSID; + reg = CR2_RECINVSID; if (smmu->features & ARM_SMMU_FEAT_E2H) reg |= CR2_E2H; + if (!(smmu->features & ARM_SMMU_FEAT_BTM)) + reg |= CR2_PTM; + writel_relaxed(reg, smmu->base + ARM_SMMU_CR2); /* Stream table */ @@ -2564,6 +2569,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) { u32 reg; bool coherent = smmu->features & ARM_SMMU_FEAT_COHERENCY; + bool vhe = cpus_have_cap(ARM64_HAS_VIRT_HOST_EXTN); /* IDR0 */ reg = readl_relaxed(smmu->base + ARM_SMMU_IDR0); @@ -2613,10 +2619,19 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) if (reg & IDR0_HYP) { smmu->features |= ARM_SMMU_FEAT_HYP; - if (cpus_have_cap(ARM64_HAS_VIRT_HOST_EXTN)) + if (vhe) smmu->features |= ARM_SMMU_FEAT_E2H; } + /* + * If the CPU is using VHE, but the SMMU doesn't support it, the SMMU + * will create TLB entries for NH-EL1 world and will miss the + * broadcasted TLB invalidations that target EL2-E2H world. Don't enable + * BTM in that case. + */ + if (reg & IDR0_BTM && (!vhe || reg & IDR0_HYP)) + smmu->features |= ARM_SMMU_FEAT_BTM; + /* * The coherency feature as set by FW is used in preference to the ID * register, but warn on mismatch. -- 2.17.0