[PATCH v14 02/10] iommu/arm-smmu-v3: Use device properties for pasid-num-bits

Jean-Philippe Brucker
2021-04-01T18:31:56Z

The pasid-num-bits property shouldn't need a dedicated fwspec field,
it's a job for device properties. Add properties for IORT, and access
the number of PASID bits using device_property_read_u32().

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
---
include/linux/iommu.h | 2 --
drivers/acpi/arm64/iort.c | 13 +++++++------
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 ++-
drivers/iommu/of_iommu.c | 5 -----
4 files changed, 9 insertions(+), 14 deletions(-)

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 1d422bf722a1..16ce75693d83 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -572,7 +572,6 @@ struct iommu_group *fsl_mc_device_group(struct device *dev);
* @ops: ops for this device's IOMMU
* @iommu_fwnode: firmware handle for this device's IOMMU
* @flags: IOMMU_FWSPEC_* flags
- * @num_pasid_bits: number of PASID bits supported by this device
* @num_ids: number of associated device IDs
* @ids: IDs which this device may present to the IOMMU
*/
@@ -580,7 +579,6 @@ struct iommu_fwspec {
const struct iommu_ops *ops;
struct fwnode_handle *iommu_fwnode;
u32 flags;
- u32 num_pasid_bits;
unsigned int num_ids;
u32 ids[];
};
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 2494138a6905..3912a1f6058e 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -968,15 +968,16 @@ static int iort_pci_iommu_init(struct pci_dev *pdev, u16 alias, void *data)
static void iort_named_component_init(struct device *dev,
struct acpi_iort_node *node)
{
+ struct property_entry props[2] = {};
struct acpi_iort_named_component *nc;
- struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
-
- if (!fwspec)
- return;

nc = (struct acpi_iort_named_component *)node->node_data;
- fwspec->num_pasid_bits = FIELD_GET(ACPI_IORT_NC_PASID_BITS,
- nc->node_flags);
+ props[0] = PROPERTY_ENTRY_U32("pasid-num-bits",
+ FIELD_GET(ACPI_IORT_NC_PASID_BITS,
+ nc->node_flags));
+
+ if (device_add_properties(dev, props))
+ dev_warn(dev, "Could not add device properties\n");
}

static int iort_nc_iommu_map(struct device *dev, struct acpi_iort_node *node)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 941ba5484731..bd77495023c8 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2395,7 +2395,8 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
}
}

- master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits);
+ device_property_read_u32(dev, "pasid-num-bits", &master->ssid_bits);
+ master->ssid_bits = min(smmu->ssid_bits, master->ssid_bits);

/*
* Note that PASID must be enabled before, and disabled after ATS:
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index e505b9130a1c..a9d2df001149 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -210,11 +210,6 @@ const struct iommu_ops *of_iommu_configure(struct device *dev,
of_pci_iommu_init, &info);
} else {
err = of_iommu_configure_device(master_np, dev, id);
-
- fwspec = dev_iommu_fwspec_get(dev);
- if (!err && fwspec)
- of_property_read_u32(master_np, "pasid-num-bits",
- &fwspec->num_pasid_bits);
}

/*
--
2.31.1