Commit 8565915e authored by Jason Gunthorpe's avatar Jason Gunthorpe Committed by Joerg Roedel
Browse files

iommu/fsl_pamu: Implement a PLATFORM domain 



This driver is nonsensical. To not block migrating the core API away from
NULL default_domains give it a hacky of a PLATFORM domain that keeps it
working exactly as it always did.

Leave some comments around to warn away any future people looking at this.

Reviewed-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarJerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/5-v8-81230027b2fa+9d-iommu_all_defdom_jgg@nvidia.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent e04c7487

drivers/iommu/fsl_pamu_domain.c

+38 −3
Original line number Diff line number Diff line
@@ -196,6 +196,13 @@ static struct iommu_domain *fsl_pamu_domain_alloc(unsigned type) 
{

	struct fsl_dma_domain *dma_domain;



	/*

	 * FIXME: This isn't creating an unmanaged domain since the

	 * default_domain_ops do not have any map/unmap function it doesn't meet

	 * the requirements for __IOMMU_DOMAIN_PAGING. The only purpose seems to

	 * allow drivers/soc/fsl/qbman/qman_portal.c to do

	 * fsl_pamu_configure_l1_stash()

	 */

	if (type != IOMMU_DOMAIN_UNMANAGED)

		return NULL;
@@ -283,15 +290,33 @@ static int fsl_pamu_attach_device(struct iommu_domain *domain, 
	return ret;

}



static void fsl_pamu_set_platform_dma(struct device *dev)

/*

 * FIXME: fsl/pamu is completely broken in terms of how it works with the iommu

 * API. Immediately after probe the HW is left in an IDENTITY translation and

 * the driver provides a non-working UNMANAGED domain that it can switch over

 * to. However it cannot switch back to an IDENTITY translation, instead it

 * switches to what looks like BLOCKING.

 */

static int fsl_pamu_platform_attach(struct iommu_domain *platform_domain,

				    struct device *dev)

{

	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);

	struct fsl_dma_domain *dma_domain = to_fsl_dma_domain(domain);

	struct fsl_dma_domain *dma_domain;

	const u32 *prop;

	int len;

	struct pci_dev *pdev = NULL;

	struct pci_controller *pci_ctl;



	/*

	 * Hack to keep things working as they always have, only leaving an

	 * UNMANAGED domain makes it BLOCKING.

	 */

	if (domain == platform_domain || !domain ||

	    domain->type != IOMMU_DOMAIN_UNMANAGED)

		return 0;



	dma_domain = to_fsl_dma_domain(domain);



	/*

	 * Use LIODN of the PCI controller while detaching a

	 * PCI device.
@@ -312,8 +337,18 @@ static void fsl_pamu_set_platform_dma(struct device *dev) 
		detach_device(dev, dma_domain);

	else

		pr_debug("missing fsl,liodn property at %pOF\n", dev->of_node);

	return 0;

}



static struct iommu_domain_ops fsl_pamu_platform_ops = {

	.attach_dev = fsl_pamu_platform_attach,

};



static struct iommu_domain fsl_pamu_platform_domain = {

	.type = IOMMU_DOMAIN_PLATFORM,

	.ops = &fsl_pamu_platform_ops,

};



/* Set the domain stash attribute */

int fsl_pamu_configure_l1_stash(struct iommu_domain *domain, u32 cpu)

{
@@ -395,11 +430,11 @@ static struct iommu_device *fsl_pamu_probe_device(struct device *dev) 
}



static const struct iommu_ops fsl_pamu_ops = {

	.default_domain = &fsl_pamu_platform_domain,

	.capable	= fsl_pamu_capable,

	.domain_alloc	= fsl_pamu_domain_alloc,

	.probe_device	= fsl_pamu_probe_device,

	.device_group   = fsl_pamu_device_group,

	.set_platform_dma_ops = fsl_pamu_set_platform_dma,

	.default_domain_ops = &(const struct iommu_domain_ops) {

		.attach_dev	= fsl_pamu_attach_device,

		.iova_to_phys	= fsl_pamu_iova_to_phys,