From 5702ee24182f9b3e33476b74b5c92a4f913ad9bd Mon Sep 17 00:00:00 2001 From: Jean-Philippe Brucker Date: Wed, 17 Apr 2019 19:24:42 +0100 Subject: [PATCH] ACPI/IORT: Check ATS capability in root complex nodes Root complex node in IORT has a bit telling whether it supports ATS or not. Store this bit in the IOMMU fwspec when setting up a device, so it can be accessed later by an IOMMU driver. In the future we'll probably want to store this bit at the host bridge or SMMU rather than in each endpoint. Acked-by: Lorenzo Pieralisi Signed-off-by: Jean-Philippe Brucker Signed-off-by: Will Deacon --- drivers/acpi/arm64/iort.c | 11 +++++++++++ include/linux/iommu.h | 4 ++++ 2 files changed, 15 insertions(+) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index e48894e002ba..4000902e57f0 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -1028,6 +1028,14 @@ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) dev_dbg(dev, "dma_pfn_offset(%#08llx)\n", offset); } +static bool iort_pci_rc_supports_ats(struct acpi_iort_node *node) +{ + struct acpi_iort_root_complex *pci_rc; + + pci_rc = (struct acpi_iort_root_complex *)node->node_data; + return pci_rc->ats_attribute & ACPI_IORT_ATS_SUPPORTED; +} + /** * iort_iommu_configure - Set-up IOMMU configuration for a device. * @@ -1063,6 +1071,9 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev) info.node = node; err = pci_for_each_dma_alias(to_pci_dev(dev), iort_pci_iommu_init, &info); + + if (!err && iort_pci_rc_supports_ats(node)) + dev->iommu_fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS; } else { int i = 0; diff --git a/include/linux/iommu.h b/include/linux/iommu.h index ffbbc7e39cee..6c1b4c900191 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -392,10 +392,14 @@ struct iommu_fwspec { const struct iommu_ops *ops; struct fwnode_handle *iommu_fwnode; void *iommu_priv; + u32 flags; unsigned int num_ids; u32 ids[1]; }; +/* ATS is supported */ +#define IOMMU_FWSPEC_PCI_RC_ATS (1 << 0) + int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode, const struct iommu_ops *ops); void iommu_fwspec_free(struct device *dev); -- 2.45.2