From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Murphy Subject: [RFC PATCH] iommu/arm-smmu: Add global SMR masking property Date: Fri, 16 Dec 2016 13:19:29 +0000 Message-ID: Return-path: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Cc: will.deacon-5wv7dgnIgG8@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, stuart.yoder-3arQi8VN3Tc@public.gmane.org List-Id: devicetree@vger.kernel.org The current SMR masking support using a 2-cell iommu-specifier is primarily intended to handle individual masters with large and/or complex Stream ID assignments; it quickly gets a bit clunky in other SMR use-cases where we just want to consistently mask out the same part of every Stream ID (e.g. for MMU-500 configurations where the appended TBU number gets in the way unnecessarily). Let's add a new property to allow a single global mask value to better fit the latter situation. CC: Stuart Yoder Signed-off-by: Robin Murphy --- Compile-tested only... Documentation/devicetree/bindings/iommu/arm,smmu.txt | 8 ++++++++ drivers/iommu/arm-smmu.c | 4 +++- 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt index e862d1485205..98f5cbe5fdb4 100644 --- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt +++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt @@ -60,6 +60,14 @@ conditions. aliases of secure registers have to be used during SMMU configuration. +- stream-match-mask : Specifies a fixed SMR mask value to combine with + the Stream ID value from every iommu-specifier. This + may be used instead of an "#iommu-cells" value of 2 + when there is no need for per-master SMR masks, but + it is still desired to mask some portion of every + Stream ID (e.g. for certain MMU-500 configurations + given globally unique external IDs). + ** Deprecated properties: - mmu-masters (deprecated in favour of the generic "iommus" binding) : diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 8f7281444551..f1abcb7dde36 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -1534,13 +1534,15 @@ static int arm_smmu_domain_set_attr(struct iommu_domain *domain, static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args) { - u32 fwid = 0; + u32 mask, fwid = 0; if (args->args_count > 0) fwid |= (u16)args->args[0]; if (args->args_count > 1) fwid |= (u16)args->args[1] << SMR_MASK_SHIFT; + else if (!of_property_read_u32(args->np, "stream-match-mask", &mask)) + fwid |= (u16)mask << SMR_MASK_SHIFT; return iommu_fwspec_add_ids(dev, &fwid, 1); } -- 2.10.2.dirty -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: robin.murphy@arm.com (Robin Murphy) Date: Fri, 16 Dec 2016 13:19:29 +0000 Subject: [RFC PATCH] iommu/arm-smmu: Add global SMR masking property Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The current SMR masking support using a 2-cell iommu-specifier is primarily intended to handle individual masters with large and/or complex Stream ID assignments; it quickly gets a bit clunky in other SMR use-cases where we just want to consistently mask out the same part of every Stream ID (e.g. for MMU-500 configurations where the appended TBU number gets in the way unnecessarily). Let's add a new property to allow a single global mask value to better fit the latter situation. CC: Stuart Yoder Signed-off-by: Robin Murphy --- Compile-tested only... Documentation/devicetree/bindings/iommu/arm,smmu.txt | 8 ++++++++ drivers/iommu/arm-smmu.c | 4 +++- 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt index e862d1485205..98f5cbe5fdb4 100644 --- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt +++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt @@ -60,6 +60,14 @@ conditions. aliases of secure registers have to be used during SMMU configuration. +- stream-match-mask : Specifies a fixed SMR mask value to combine with + the Stream ID value from every iommu-specifier. This + may be used instead of an "#iommu-cells" value of 2 + when there is no need for per-master SMR masks, but + it is still desired to mask some portion of every + Stream ID (e.g. for certain MMU-500 configurations + given globally unique external IDs). + ** Deprecated properties: - mmu-masters (deprecated in favour of the generic "iommus" binding) : diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 8f7281444551..f1abcb7dde36 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -1534,13 +1534,15 @@ static int arm_smmu_domain_set_attr(struct iommu_domain *domain, static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args) { - u32 fwid = 0; + u32 mask, fwid = 0; if (args->args_count > 0) fwid |= (u16)args->args[0]; if (args->args_count > 1) fwid |= (u16)args->args[1] << SMR_MASK_SHIFT; + else if (!of_property_read_u32(args->np, "stream-match-mask", &mask)) + fwid |= (u16)mask << SMR_MASK_SHIFT; return iommu_fwspec_add_ids(dev, &fwid, 1); } -- 2.10.2.dirty