Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 180 insertions, 0 deletions

diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
new file mode 100644
index 000000000..1fa1db3be
--- /dev/null
+++ b/drivers/iommu/of_iommu.c
@@ -0,0 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * OF helpers for IOMMU
+ *
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#include <linux/export.h>
+#include <linux/iommu.h>
+#include <linux/limits.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of.h>
+#include <linux/of_iommu.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/fsl/mc.h>
+
+#define NO_IOMMU	1
+
+static int of_iommu_xlate(struct device *dev,
+			  struct of_phandle_args *iommu_spec)
+{
+	const struct iommu_ops *ops;
+	struct fwnode_handle *fwnode = &iommu_spec->np->fwnode;
+	int ret;
+
+	ops = iommu_ops_from_fwnode(fwnode);
+	if ((ops && !ops->of_xlate) ||
+	    !of_device_is_available(iommu_spec->np))
+		return NO_IOMMU;
+
+	ret = iommu_fwspec_init(dev, &iommu_spec->np->fwnode, ops);
+	if (ret)
+		return ret;
+	/*
+	 * The otherwise-empty fwspec handily serves to indicate the specific
+	 * IOMMU device we're waiting for, which will be useful if we ever get
+	 * a proper probe-ordering dependency mechanism in future.
+	 */
+	if (!ops)
+		return driver_deferred_probe_check_state(dev);
+
+	if (!try_module_get(ops->owner))
+		return -ENODEV;
+
+	ret = ops->of_xlate(dev, iommu_spec);
+	module_put(ops->owner);
+	return ret;
+}
+
+static int of_iommu_configure_dev_id(struct device_node *master_np,
+				     struct device *dev,
+				     const u32 *id)
+{
+	struct of_phandle_args iommu_spec = { .args_count = 1 };
+	int err;
+
+	err = of_map_id(master_np, *id, "iommu-map",
+			 "iommu-map-mask", &iommu_spec.np,
+			 iommu_spec.args);
+	if (err)
+		return err == -ENODEV ? NO_IOMMU : err;
+
+	err = of_iommu_xlate(dev, &iommu_spec);
+	of_node_put(iommu_spec.np);
+	return err;
+}
+
+static int of_iommu_configure_dev(struct device_node *master_np,
+				  struct device *dev)
+{
+	struct of_phandle_args iommu_spec;
+	int err = NO_IOMMU, idx = 0;
+
+	while (!of_parse_phandle_with_args(master_np, "iommus",
+					   "#iommu-cells",
+					   idx, &iommu_spec)) {
+		err = of_iommu_xlate(dev, &iommu_spec);
+		of_node_put(iommu_spec.np);
+		idx++;
+		if (err)
+			break;
+	}
+
+	return err;
+}
+
+struct of_pci_iommu_alias_info {
+	struct device *dev;
+	struct device_node *np;
+};
+
+static int of_pci_iommu_init(struct pci_dev *pdev, u16 alias, void *data)
+{
+	struct of_pci_iommu_alias_info *info = data;
+	u32 input_id = alias;
+
+	return of_iommu_configure_dev_id(info->np, info->dev, &input_id);
+}
+
+static int of_iommu_configure_device(struct device_node *master_np,
+				     struct device *dev, const u32 *id)
+{
+	return (id) ? of_iommu_configure_dev_id(master_np, dev, id) :
+		      of_iommu_configure_dev(master_np, dev);
+}
+
+const struct iommu_ops *of_iommu_configure(struct device *dev,
+					   struct device_node *master_np,
+					   const u32 *id)
+{
+	const struct iommu_ops *ops = NULL;
+	struct iommu_fwspec *fwspec;
+	int err = NO_IOMMU;
+
+	if (!master_np)
+		return NULL;
+
+	/* Serialise to make dev->iommu stable under our potential fwspec */
+	mutex_lock(&iommu_probe_device_lock);
+	fwspec = dev_iommu_fwspec_get(dev);
+	if (fwspec) {
+		if (fwspec->ops) {
+			mutex_unlock(&iommu_probe_device_lock);
+			return fwspec->ops;
+		}
+		/* In the deferred case, start again from scratch */
+		iommu_fwspec_free(dev);
+	}
+
+	/*
+	 * We don't currently walk up the tree looking for a parent IOMMU.
+	 * See the `Notes:' section of
+	 * Documentation/devicetree/bindings/iommu/iommu.txt
+	 */
+	if (dev_is_pci(dev)) {
+		struct of_pci_iommu_alias_info info = {
+			.dev = dev,
+			.np = master_np,
+		};
+
+		pci_request_acs();
+		err = pci_for_each_dma_alias(to_pci_dev(dev),
+					     of_pci_iommu_init, &info);
+	} else {
+		err = of_iommu_configure_device(master_np, dev, id);
+	}
+
+	/*
+	 * Two success conditions can be represented by non-negative err here:
+	 * >0 : there is no IOMMU, or one was unavailable for non-fatal reasons
+	 *  0 : we found an IOMMU, and dev->fwspec is initialised appropriately
+	 * <0 : any actual error
+	 */
+	if (!err) {
+		/* The fwspec pointer changed, read it again */
+		fwspec = dev_iommu_fwspec_get(dev);
+		ops    = fwspec->ops;
+	}
+	mutex_unlock(&iommu_probe_device_lock);
+
+	/*
+	 * If we have reason to believe the IOMMU driver missed the initial
+	 * probe for dev, replay it to get things in order.
+	 */
+	if (!err && dev->bus && !device_iommu_mapped(dev))
+		err = iommu_probe_device(dev);
+
+	/* Ignore all other errors apart from EPROBE_DEFER */
+	if (err == -EPROBE_DEFER) {
+		ops = ERR_PTR(err);
+	} else if (err < 0) {
+		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
+		ops = NULL;
+	}
+
+	return ops;
+}