Commit e4f10ffe authored by Lorenzo Pieralisi's avatar Lorenzo Pieralisi Committed by Will Deacon
Browse files

iommu: Make of_iommu_set/get_ops() DT agnostic 



The of_iommu_{set/get}_ops() API is used to associate a device
tree node with a specific set of IOMMU operations. The same
kernel interface is required on systems booting with ACPI, where
devices are not associated with a device tree node, therefore
the interface requires generalization.

The struct device fwnode member represents the fwnode token associated
with the device and the struct it points at is firmware specific;
regardless, it is initialized on both ACPI and DT systems and makes an
ideal candidate to use it to associate a set of IOMMU operations to a
given device, through its struct device.fwnode member pointer, paving
the way for representing per-device iommu_ops (ie an iommu instance
associated with a device).

Convert the DT specific of_iommu_{set/get}_ops() interface to
use struct device.fwnode as a look-up token, making the interface
usable on ACPI systems and rename the data structures and the
registration API so that they are made to represent their usage
more clearly.

Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: default avatarWill Deacon <will.deacon@arm.com>
Reviewed-by: default avatarRobin Murphy <robin.murphy@arm.com>
Reviewed-by: default avatarTomasz Nowicki <tn@semihalf.com>
Tested-by: default avatarHanjun Guo <hanjun.guo@linaro.org>
Tested-by: default avatarTomasz Nowicki <tn@semihalf.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent 7936df92

drivers/iommu/iommu.c

+40 −0
Original line number Diff line number Diff line
@@ -1615,6 +1615,46 @@ out: 
	return ret;

}



struct iommu_instance {

	struct list_head list;

	struct fwnode_handle *fwnode;

	const struct iommu_ops *ops;

};

static LIST_HEAD(iommu_instance_list);

static DEFINE_SPINLOCK(iommu_instance_lock);



void iommu_register_instance(struct fwnode_handle *fwnode,

			     const struct iommu_ops *ops)

{

	struct iommu_instance *iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);



	if (WARN_ON(!iommu))

		return;



	of_node_get(to_of_node(fwnode));

	INIT_LIST_HEAD(&iommu->list);

	iommu->fwnode = fwnode;

	iommu->ops = ops;

	spin_lock(&iommu_instance_lock);

	list_add_tail(&iommu->list, &iommu_instance_list);

	spin_unlock(&iommu_instance_lock);

}



const struct iommu_ops *iommu_get_instance(struct fwnode_handle *fwnode)

{

	struct iommu_instance *instance;

	const struct iommu_ops *ops = NULL;



	spin_lock(&iommu_instance_lock);

	list_for_each_entry(instance, &iommu_instance_list, list)

		if (instance->fwnode == fwnode) {

			ops = instance->ops;

			break;

		}

	spin_unlock(&iommu_instance_lock);

	return ops;

}



int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,

		      const struct iommu_ops *ops)

{

drivers/iommu/of_iommu.c

+0 −39
Original line number Diff line number Diff line
@@ -96,45 +96,6 @@ int of_get_dma_window(struct device_node *dn, const char *prefix, int index, 
}

EXPORT_SYMBOL_GPL(of_get_dma_window);



struct of_iommu_node {

	struct list_head list;

	struct device_node *np;

	const struct iommu_ops *ops;

};

static LIST_HEAD(of_iommu_list);

static DEFINE_SPINLOCK(of_iommu_lock);



void of_iommu_set_ops(struct device_node *np, const struct iommu_ops *ops)

{

	struct of_iommu_node *iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);



	if (WARN_ON(!iommu))

		return;



	of_node_get(np);

	INIT_LIST_HEAD(&iommu->list);

	iommu->np = np;

	iommu->ops = ops;

	spin_lock(&of_iommu_lock);

	list_add_tail(&iommu->list, &of_iommu_list);

	spin_unlock(&of_iommu_lock);

}



const struct iommu_ops *of_iommu_get_ops(struct device_node *np)

{

	struct of_iommu_node *node;

	const struct iommu_ops *ops = NULL;



	spin_lock(&of_iommu_lock);

	list_for_each_entry(node, &of_iommu_list, list)

		if (node->np == np) {

			ops = node->ops;

			break;

		}

	spin_unlock(&of_iommu_lock);

	return ops;

}



static int __get_pci_rid(struct pci_dev *pdev, u16 alias, void *data)

{

	struct of_phandle_args *iommu_spec = data;

include/linux/iommu.h

+14 −0
Original line number Diff line number Diff line
@@ -351,6 +351,9 @@ int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode, 
		      const struct iommu_ops *ops);

void iommu_fwspec_free(struct device *dev);

int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids);

void iommu_register_instance(struct fwnode_handle *fwnode,

			     const struct iommu_ops *ops);

const struct iommu_ops *iommu_get_instance(struct fwnode_handle *fwnode);



#else /* CONFIG_IOMMU_API */
@@ -580,6 +583,17 @@ static inline int iommu_fwspec_add_ids(struct device *dev, u32 *ids, 
	return -ENODEV;

}



static inline void iommu_register_instance(struct fwnode_handle *fwnode,

					   const struct iommu_ops *ops)

{

}



static inline

const struct iommu_ops *iommu_get_instance(struct fwnode_handle *fwnode)

{

	return NULL;

}



#endif /* CONFIG_IOMMU_API */



#endif /* __LINUX_IOMMU_H */

include/linux/of_iommu.h

+10 −2
Original line number Diff line number Diff line
@@ -31,8 +31,16 @@ static inline const struct iommu_ops *of_iommu_configure(struct device *dev, 


#endif	/* CONFIG_OF_IOMMU */



void of_iommu_set_ops(struct device_node *np, const struct iommu_ops *ops);

const struct iommu_ops *of_iommu_get_ops(struct device_node *np);

static inline void of_iommu_set_ops(struct device_node *np,

				    const struct iommu_ops *ops)

{

	iommu_register_instance(&np->fwnode, ops);

}



static inline const struct iommu_ops *of_iommu_get_ops(struct device_node *np)

{

	return iommu_get_instance(&np->fwnode);

}



extern struct of_device_id __iommu_of_table;

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