iommu/omap: Implement an IDENTITY domain

What omap does during omap_iommu_set_platform_dma() is actually putting
the iommu into identity mode.

Move to the new core support for ARM_DMA_USE_IOMMU by defining
ops->identity_domain.

This driver does not support IOMMU_DOMAIN_DMA, however it cannot be
compiled on ARM64 either. Most likely it is fine to support dma-iommu.c

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/13-v8-81230027b2fa+9d-iommu_all_defdom_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index 537e402f9bba97144792a3c66249f3e0f8bea102..34340ef15241bc9caa49b2f532507bb2921ffb7f 100644 (file)
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -1555,16 +1555,31 @@ static void _omap_iommu_detach_dev(struct omap_iommu_domain *omap_domain,
        omap_domain->dev = NULL;
 }
 
-static void omap_iommu_set_platform_dma(struct device *dev)
+static int omap_iommu_identity_attach(struct iommu_domain *identity_domain,
+                                     struct device *dev)
 {
        struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
-       struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
+       struct omap_iommu_domain *omap_domain;
 
+       if (domain == identity_domain || !domain)
+               return 0;
+
+       omap_domain = to_omap_domain(domain);
        spin_lock(&omap_domain->lock);
        _omap_iommu_detach_dev(omap_domain, dev);
        spin_unlock(&omap_domain->lock);
+       return 0;
 }
 
+static struct iommu_domain_ops omap_iommu_identity_ops = {
+       .attach_dev = omap_iommu_identity_attach,
+};
+
+static struct iommu_domain omap_iommu_identity_domain = {
+       .type = IOMMU_DOMAIN_IDENTITY,
+       .ops = &omap_iommu_identity_ops,
+};
+
 static struct iommu_domain *omap_iommu_domain_alloc(unsigned type)
 {
        struct omap_iommu_domain *omap_domain;
@@ -1732,11 +1747,11 @@ static struct iommu_group *omap_iommu_device_group(struct device *dev)
 }
 
 static const struct iommu_ops omap_iommu_ops = {
+       .identity_domain = &omap_iommu_identity_domain,
        .domain_alloc   = omap_iommu_domain_alloc,
        .probe_device   = omap_iommu_probe_device,
        .release_device = omap_iommu_release_device,
        .device_group   = omap_iommu_device_group,
-       .set_platform_dma_ops = omap_iommu_set_platform_dma,
        .pgsize_bitmap  = OMAP_IOMMU_PGSIZES,
        .default_domain_ops = &(const struct iommu_domain_ops) {
                .attach_dev     = omap_iommu_attach_dev,