Backport Linux RISC-V IOMMU Support

Documentation/devicetree/bindings/iommu/riscv,iommu.yaml

@@ -0,0 +1,147 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iommu/riscv,iommu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V IOMMU Architecture Implementation
+
+maintainers:
+  - Tomasz Jeznach <tjeznach@rivosinc.com>
+
+description: |
+  The RISC-V IOMMU provides memory address translation and isolation for
+  input and output devices, supporting per-device translation context,
+  shared process address spaces including the ATS and PRI components of
+  the PCIe specification, two stage address translation and MSI remapping.
+  It supports identical translation table format to the RISC-V address
+  translation tables with page level access and protection attributes.
+  Hardware uses in-memory command and fault reporting queues with wired
+  interrupt or MSI notifications.
+
+  Visit https://github.com/riscv-non-isa/riscv-iommu for more details.
+
+  For information on assigning RISC-V IOMMU to its peripheral devices,
+  see generic IOMMU bindings.
+
+properties:
+  # For PCIe IOMMU hardware compatible property should contain the vendor
+  # and device ID according to the PCI Bus Binding specification.
+  # Since PCI provides built-in identification methods, compatible is not
+  # actually required. For non-PCIe hardware implementations 'riscv,iommu'
+  # should be specified along with 'reg' property providing MMIO location.
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - qemu,riscv-iommu
+          - const: riscv,iommu
+      - items:
+          - enum:
+              - pci1efd,edf1
+          - const: riscv,pci-iommu
+
+  reg:
+    maxItems: 1
+    description:
+      For non-PCI devices this represents base address and size of for the
+      IOMMU memory mapped registers interface.
+      For PCI IOMMU hardware implementation this should represent an address
+      of the IOMMU, as defined in the PCI Bus Binding reference.
+
+  '#iommu-cells':
+    const: 1
+    description:
+      The single cell describes the requester id emitted by a master to the
+      IOMMU.
+
+  interrupts:
+    minItems: 1
+    maxItems: 4
+    description:
+      Wired interrupt vectors available for RISC-V IOMMU to notify the
+      RISC-V HARTS. The cause to interrupt vector is software defined
+      using IVEC IOMMU register.
+
+  msi-parent: true
+
+  power-domains:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - '#iommu-cells'
+
+additionalProperties: false
+
+examples:
+  - |+
+    /* Example 1 (IOMMU device with wired interrupts) */
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    iommu1: iommu@1bccd000 {
+        compatible = "qemu,riscv-iommu", "riscv,iommu";
+        reg = <0x1bccd000 0x1000>;
+        interrupt-parent = <&aplic_smode>;
+        interrupts = <32 IRQ_TYPE_LEVEL_HIGH>,
+                     <33 IRQ_TYPE_LEVEL_HIGH>,
+                     <34 IRQ_TYPE_LEVEL_HIGH>,
+                     <35 IRQ_TYPE_LEVEL_HIGH>;
+        #iommu-cells = <1>;
+    };
+
+    /* Device with two IOMMU device IDs, 0 and 7 */
+    master1 {
+        iommus = <&iommu1 0>, <&iommu1 7>;
+    };
+
+  - |+
+    /* Example 2 (IOMMU device with shared wired interrupt) */
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    iommu2: iommu@1bccd000 {
+        compatible = "qemu,riscv-iommu", "riscv,iommu";
+        reg = <0x1bccd000 0x1000>;
+        interrupt-parent = <&aplic_smode>;
+        interrupts = <32 IRQ_TYPE_LEVEL_HIGH>;
+        #iommu-cells = <1>;
+    };
+
+  - |+
+    /* Example 3 (IOMMU device with MSIs) */
+    iommu3: iommu@1bcdd000 {
+        compatible = "qemu,riscv-iommu", "riscv,iommu";
+        reg = <0x1bccd000 0x1000>;
+        msi-parent = <&imsics_smode>;
+        #iommu-cells = <1>;
+    };
+
+  - |+
+    /* Example 4 (IOMMU PCIe device with MSIs) */
+    bus {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        pcie@30000000 {
+            device_type = "pci";
+            #address-cells = <3>;
+            #size-cells = <2>;
+            reg = <0x0 0x30000000  0x0 0x1000000>;
+            ranges = <0x02000000 0x0 0x41000000  0x0 0x41000000  0x0 0x0f000000>;
+
+            /*
+             * The IOMMU manages all functions in this PCI domain except
+             * itself. Omit BDF 00:01.0.
+             */
+            iommu-map = <0x0 &iommu0 0x0 0x8>,
+                        <0x9 &iommu0 0x9 0xfff7>;
+
+            /* The IOMMU programming interface uses slot 00:01.0 */
+            iommu0: iommu@1,0 {
+               compatible = "pci1efd,edf1", "riscv,pci-iommu";
+               reg = <0x800 0 0 0 0>;
+               #iommu-cells = <1>;
+            };
+        };
+    };

MAINTAINERS

@@ -18449,6 +18449,15 @@ F:	arch/riscv/
 N:	riscv
 K:	riscv
 
+RISC-V IOMMU
+M:	Tomasz Jeznach <tjeznach@rivosinc.com>
+L:	iommu@lists.linux.dev
+L:	linux-riscv@lists.infradead.org
+S:	Maintained
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux.git
+F:	Documentation/devicetree/bindings/iommu/riscv,iommu.yaml
+F:	drivers/iommu/riscv/
+
 RISC-V MICROCHIP FPGA SUPPORT
 M:	Conor Dooley <conor.dooley@microchip.com>
 M:	Daire McNamara <daire.mcnamara@microchip.com>

drivers/iommu/Kconfig

@@ -187,6 +187,7 @@ config MSM_IOMMU
 source "drivers/iommu/amd/Kconfig"
 source "drivers/iommu/intel/Kconfig"
 source "drivers/iommu/iommufd/Kconfig"
+source "drivers/iommu/riscv/Kconfig"
 
 config IRQ_REMAP
 	bool "Support for Interrupt Remapping"

drivers/iommu/Makefile

@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-y += amd/ intel/ arm/ iommufd/
+obj-y += amd/ intel/ arm/ iommufd/ riscv/
 obj-$(CONFIG_IOMMU_API) += iommu.o
 obj-$(CONFIG_IOMMU_API) += iommu-traces.o
 obj-$(CONFIG_IOMMU_API) += iommu-sysfs.o

drivers/iommu/apple-dart.c

@@ -748,7 +748,8 @@ static void apple_dart_domain_free(struct iommu_domain *domain)
 	kfree(dart_domain);
 }
 
-static int apple_dart_of_xlate(struct device *dev, struct of_phandle_args *args)
+static int apple_dart_of_xlate(struct device *dev,
+			       const struct of_phandle_args *args)
 {
 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
 	struct platform_device *iommu_pdev = of_find_device_by_node(args->np);

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c

@@ -2760,7 +2760,8 @@ static int arm_smmu_enable_nesting(struct iommu_domain *domain)
 	return ret;
 }
 
-static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
+static int arm_smmu_of_xlate(struct device *dev,
+			     const struct of_phandle_args *args)
 {
 	return iommu_fwspec_add_ids(dev, args->args, 1);
 }

drivers/iommu/arm/arm-smmu/arm-smmu.c

@@ -1525,7 +1525,8 @@ static int arm_smmu_set_pgtable_quirks(struct iommu_domain *domain,
 	return ret;
 }
 
-static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
+static int arm_smmu_of_xlate(struct device *dev,
+			     const struct of_phandle_args *args)
 {
 	u32 mask, fwid = 0;
 

drivers/iommu/arm/arm-smmu/qcom_iommu.c

@@ -556,7 +556,8 @@ static struct iommu_device *qcom_iommu_probe_device(struct device *dev)
 	return &qcom_iommu->iommu;
 }
 
-static int qcom_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
+static int qcom_iommu_of_xlate(struct device *dev,
+			       const struct of_phandle_args *args)
 {
 	struct qcom_iommu_dev *qcom_iommu;
 	struct platform_device *iommu_pdev;

drivers/iommu/exynos-iommu.c

@@ -1429,7 +1429,7 @@ static void exynos_iommu_release_device(struct device *dev)
 }
 
 static int exynos_iommu_of_xlate(struct device *dev,
-				 struct of_phandle_args *spec)
+				 const struct of_phandle_args *spec)
 {
 	struct platform_device *sysmmu = of_find_device_by_node(spec->np);
 	struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);

drivers/iommu/intel/dmar.c

@@ -32,6 +32,7 @@
 
 #include "iommu.h"
 #include "../irq_remapping.h"
+#include "../iommu-pages.h"
 #include "perf.h"
 #include "trace.h"
 #include "perfmon.h"
@@ -1185,7 +1186,7 @@ static void free_iommu(struct intel_iommu *iommu)
 	}
 
 	if (iommu->qi) {
-		free_page((unsigned long)iommu->qi->desc);
+		iommu_free_page(iommu->qi->desc);
 		kfree(iommu->qi->desc_status);
 		kfree(iommu->qi);
 	}
@@ -1737,7 +1738,8 @@ static void __dmar_enable_qi(struct intel_iommu *iommu)
 int dmar_enable_qi(struct intel_iommu *iommu)
 {
 	struct q_inval *qi;
-	struct page *desc_page;
+	void *desc;
+	int order;
 
 	if (!ecap_qis(iommu->ecap))
 		return -ENOENT;
@@ -1758,19 +1760,19 @@ int dmar_enable_qi(struct intel_iommu *iommu)
 	 * Need two pages to accommodate 256 descriptors of 256 bits each
 	 * if the remapping hardware supports scalable mode translation.
 	 */
-	desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
-				     !!ecap_smts(iommu->ecap));
-	if (!desc_page) {
+	order = ecap_smts(iommu->ecap) ? 1 : 0;
+	desc = iommu_alloc_pages_node(iommu->node, GFP_ATOMIC, order);
+	if (!desc) {
 		kfree(qi);
 		iommu->qi = NULL;
 		return -ENOMEM;
 	}
 
-	qi->desc = page_address(desc_page);
+	qi->desc = desc;
 
 	qi->desc_status = kcalloc(QI_LENGTH, sizeof(int), GFP_ATOMIC);
 	if (!qi->desc_status) {
-		free_page((unsigned long) qi->desc);
+		iommu_free_page(qi->desc);
 		kfree(qi);
 		iommu->qi = NULL;
 		return -ENOMEM;