From 8565915e75581ba540527d1d9a2b89620002a0d0 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Wed, 13 Sep 2023 10:43:38 -0300 Subject: 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: Lu Baolu Reviewed-by: Jerry Snitselaar Signed-off-by: Jason Gunthorpe Link: https://lore.kernel.org/r/5-v8-81230027b2fa+9d-iommu_all_defdom_jgg@nvidia.com Signed-off-by: Joerg Roedel --- drivers/iommu/fsl_pamu_domain.c | 41 ++++++++++++++++++++++++++++++++++++++--- 1 file changed, 38 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/fsl_pamu_domain.c b/drivers/iommu/fsl_pamu_domain.c index 4ac0e247ec2b..e9d2bff4659b 100644 --- a/drivers/iommu/fsl_pamu_domain.c +++ b/drivers/iommu/fsl_pamu_domain.c @@ -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, -- cgit v1.2.3