Commit 5f937bc4 authored by Robin Murphy's avatar Robin Murphy Committed by Will Deacon
Browse files

OF: Simplify of_iommu_configure() 



We no longer have a notion of partially-initialised fwspecs existing,
and we also no longer need to use an iommu_ops pointer to return status
to of_dma_configure(). Clean up the remains of those, which lends itself
to clarifying the logic around the dma_range_map allocation as well.

Acked-by: default avatarRob Herring (Arm) <robh@kernel.org>
Tested-by: default avatarJean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/61972f88e31a6eda8bf5852f0853951164279a3c.1719919669.git.robin.murphy@arm.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 78596b5c

drivers/iommu/of_iommu.c

+10 −19
Original line number Diff line number Diff line
@@ -108,7 +108,6 @@ static int of_iommu_configure_device(struct device_node *master_np, 
int of_iommu_configure(struct device *dev, struct device_node *master_np,

		       const u32 *id)

{

	struct iommu_fwspec *fwspec;

	int err;



	if (!master_np)
@@ -116,15 +115,10 @@ int of_iommu_configure(struct device *dev, struct device_node *master_np, 


	/* 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) {

	if (dev_iommu_fwspec_get(dev)) {

		mutex_unlock(&iommu_probe_device_lock);

		return 0;

	}

		/* 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.
@@ -143,20 +137,17 @@ int of_iommu_configure(struct device *dev, struct device_node *master_np, 
	} else {

		err = of_iommu_configure_device(master_np, dev, id);

	}

	mutex_unlock(&iommu_probe_device_lock);



	if (err == -ENODEV || err == -EPROBE_DEFER)

		return err;

	if (err)

		goto err_log;

		iommu_fwspec_free(dev);

	mutex_unlock(&iommu_probe_device_lock);



	if (!err && dev->bus)

		err = iommu_probe_device(dev);

	if (err)

		goto err_log;

	return 0;



err_log:

	dev_dbg(dev, "Adding to IOMMU failed: %pe\n", ERR_PTR(err));

	if (err && err != -EPROBE_DEFER)

		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);



	return err;

}

drivers/of/device.c

+11 −19
Original line number Diff line number Diff line
@@ -96,8 +96,7 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, 
	const struct bus_dma_region *map = NULL;

	struct device_node *bus_np;

	u64 mask, end = 0;

	bool coherent;

	int iommu_ret;

	bool coherent, set_map = false;

	int ret;



	if (np == dev->of_node)
@@ -118,6 +117,7 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, 
	} else {

		/* Determine the overall bounds of all DMA regions */

		end = dma_range_map_max(map);

		set_map = true;

	}



	/*
@@ -144,7 +144,7 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, 
	dev->coherent_dma_mask &= mask;

	*dev->dma_mask &= mask;

	/* ...but only set bus limit and range map if we found valid dma-ranges earlier */

	if (!ret) {

	if (set_map) {

		dev->bus_dma_limit = end;

		dev->dma_range_map = map;

	}
@@ -153,29 +153,21 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, 
	dev_dbg(dev, "device is%sdma coherent\n",

		coherent ? " " : " not ");



	iommu_ret = of_iommu_configure(dev, np, id);

	if (iommu_ret == -EPROBE_DEFER) {

	ret = of_iommu_configure(dev, np, id);

	if (ret == -EPROBE_DEFER) {

		/* Don't touch range map if it wasn't set from a valid dma-ranges */

		if (!ret)

		if (set_map)

			dev->dma_range_map = NULL;

		kfree(map);

		return -EPROBE_DEFER;

	} else if (iommu_ret == -ENODEV) {

		dev_dbg(dev, "device is not behind an iommu\n");

	} else if (iommu_ret) {

		dev_err(dev, "iommu configuration for device failed with %pe\n",

			ERR_PTR(iommu_ret));



		/*

		 * Historically this routine doesn't fail driver probing

		 * due to errors in of_iommu_configure()

		 */

	} else

		dev_dbg(dev, "device is behind an iommu\n");

	}

	/* Take all other IOMMU errors to mean we'll just carry on without it */

	dev_dbg(dev, "device is%sbehind an iommu\n",

		!ret ? " " : " not ");



	arch_setup_dma_ops(dev, coherent);



	if (iommu_ret)

	if (ret)

		of_dma_set_restricted_buffer(dev, np);



	return 0;