[v2,2/6] ACPI: Move IOMMU setup code out of IORT

Message ID 20210423113836.3974972-3-jean-philippe@linaro.org
State Superseded
Headers show
Series
  • Add support for ACPI VIOT
Related show

Commit Message

Jean-Philippe Brucker April 23, 2021, 11:38 a.m.
Some of the IOMMU setup code in IORT is fairly generic and can be reused
by VIOT. Extract it from IORT.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>

---
 include/acpi/acpi_bus.h   |  3 ++
 include/linux/acpi_iort.h |  8 ++---
 drivers/acpi/arm64/iort.c | 75 +++++----------------------------------
 drivers/acpi/scan.c       | 55 +++++++++++++++++++++++++++-
 4 files changed, 69 insertions(+), 72 deletions(-)

-- 
2.31.1

Comments

Rafael J. Wysocki May 21, 2021, 4:42 p.m. | #1
On Fri, Apr 23, 2021 at 1:57 PM Jean-Philippe Brucker
<jean-philippe@linaro.org> wrote:
>

> Some of the IOMMU setup code in IORT is fairly generic and can be reused

> by VIOT. Extract it from IORT.


Except that iort_iommu_configure_id() is not really generic AFAICS.
Jean-Philippe Brucker May 26, 2021, 10:05 a.m. | #2
On Fri, May 21, 2021 at 06:42:09PM +0200, Rafael J. Wysocki wrote:
> On Fri, Apr 23, 2021 at 1:57 PM Jean-Philippe Brucker

> <jean-philippe@linaro.org> wrote:

> >

> > Some of the IOMMU setup code in IORT is fairly generic and can be reused

> > by VIOT. Extract it from IORT.

> 

> Except that iort_iommu_configure_id() is not really generic AFAICS.


I'll clarify the commit message: the parts of iort_iommu_configure_id()
that set up the IOMMU infrastructure can be extracted and reused by VIOT.
The rest of the function, that iterates over the IORT subtables, is
specific to the driver.

Thanks,
Jean

Patch

diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 3a82faac5767..41f092a269f6 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -588,6 +588,9 @@  struct acpi_pci_root {
 
 bool acpi_dma_supported(struct acpi_device *adev);
 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev);
+int acpi_iommu_fwspec_init(struct device *dev, u32 id,
+			   struct fwnode_handle *fwnode,
+			   const struct iommu_ops *ops);
 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
 		       u64 *size);
 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
diff --git a/include/linux/acpi_iort.h b/include/linux/acpi_iort.h
index f7f054833afd..f1f0842a2cb2 100644
--- a/include/linux/acpi_iort.h
+++ b/include/linux/acpi_iort.h
@@ -35,8 +35,7 @@  void acpi_configure_pmsi_domain(struct device *dev);
 int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id);
 /* IOMMU interface */
 int iort_dma_get_ranges(struct device *dev, u64 *size);
-const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
-						const u32 *id_in);
+int iort_iommu_configure_id(struct device *dev, const u32 *id_in);
 int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head);
 phys_addr_t acpi_iort_dma_get_max_cpu_address(void);
 #else
@@ -50,9 +49,8 @@  static inline void acpi_configure_pmsi_domain(struct device *dev) { }
 /* IOMMU interface */
 static inline int iort_dma_get_ranges(struct device *dev, u64 *size)
 { return -ENODEV; }
-static inline const struct iommu_ops *iort_iommu_configure_id(
-				      struct device *dev, const u32 *id_in)
-{ return NULL; }
+static inline int iort_iommu_configure_id(struct device *dev, const u32 *id_in)
+{ return -ENODEV; }
 static inline
 int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head)
 { return 0; }
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index a940be1cf2af..b5b021e064b6 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -806,23 +806,6 @@  static struct acpi_iort_node *iort_get_msi_resv_iommu(struct device *dev)
 	return NULL;
 }
 
-static inline const struct iommu_ops *iort_fwspec_iommu_ops(struct device *dev)
-{
-	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
-
-	return (fwspec && fwspec->ops) ? fwspec->ops : NULL;
-}
-
-static inline int iort_add_device_replay(struct device *dev)
-{
-	int err = 0;
-
-	if (dev->bus && !device_iommu_mapped(dev))
-		err = iommu_probe_device(dev);
-
-	return err;
-}
-
 /**
  * iort_iommu_msi_get_resv_regions - Reserved region driver helper
  * @dev: Device from iommu_get_resv_regions()
@@ -900,18 +883,6 @@  static inline bool iort_iommu_driver_enabled(u8 type)
 	}
 }
 
-static int arm_smmu_iort_xlate(struct device *dev, u32 streamid,
-			       struct fwnode_handle *fwnode,
-			       const struct iommu_ops *ops)
-{
-	int ret = iommu_fwspec_init(dev, fwnode, ops);
-
-	if (!ret)
-		ret = iommu_fwspec_add_ids(dev, &streamid, 1);
-
-	return ret;
-}
-
 static bool iort_pci_rc_supports_ats(struct acpi_iort_node *node)
 {
 	struct acpi_iort_root_complex *pci_rc;
@@ -946,7 +917,7 @@  static int iort_iommu_xlate(struct device *dev, struct acpi_iort_node *node,
 		return iort_iommu_driver_enabled(node->type) ?
 		       -EPROBE_DEFER : -ENODEV;
 
-	return arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops);
+	return acpi_iommu_fwspec_init(dev, streamid, iort_fwnode, ops);
 }
 
 struct iort_pci_alias_info {
@@ -1020,24 +991,14 @@  static int iort_nc_iommu_map_id(struct device *dev,
  * @dev: device to configure
  * @id_in: optional input id const value pointer
  *
- * Returns: iommu_ops pointer on configuration success
- *          NULL on configuration failure
+ * Returns: 0 on success, <0 on failure
  */
-const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
-						const u32 *id_in)
+int iort_iommu_configure_id(struct device *dev, const u32 *id_in)
 {
 	struct acpi_iort_node *node;
-	const struct iommu_ops *ops;
+	const struct iommu_ops *ops = NULL;
 	int err = -ENODEV;
 
-	/*
-	 * If we already translated the fwspec there
-	 * is nothing left to do, return the iommu_ops.
-	 */
-	ops = iort_fwspec_iommu_ops(dev);
-	if (ops)
-		return ops;
-
 	if (dev_is_pci(dev)) {
 		struct iommu_fwspec *fwspec;
 		struct pci_bus *bus = to_pci_dev(dev)->bus;
@@ -1046,7 +1007,7 @@  const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
 		node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
 				      iort_match_node_callback, &bus->dev);
 		if (!node)
-			return NULL;
+			return -ENODEV;
 
 		info.node = node;
 		err = pci_for_each_dma_alias(to_pci_dev(dev),
@@ -1059,7 +1020,7 @@  const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
 		node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
 				      iort_match_node_callback, dev);
 		if (!node)
-			return NULL;
+			return -ENODEV;
 
 		err = id_in ? iort_nc_iommu_map_id(dev, node, id_in) :
 			      iort_nc_iommu_map(dev, node);
@@ -1068,32 +1029,14 @@  const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
 			iort_named_component_init(dev, node);
 	}
 
-	/*
-	 * If we have reason to believe the IOMMU driver missed the initial
-	 * add_device callback for dev, replay it to get things in order.
-	 */
-	if (!err) {
-		ops = iort_fwspec_iommu_ops(dev);
-		err = iort_add_device_replay(dev);
-	}
-
-	/* Ignore all other errors apart from EPROBE_DEFER */
-	if (err == -EPROBE_DEFER) {
-		ops = ERR_PTR(err);
-	} else if (err) {
-		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
-		ops = NULL;
-	}
-
-	return ops;
+	return err;
 }
 
 #else
 int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head)
 { return 0; }
-const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
-						const u32 *input_id)
-{ return NULL; }
+int iort_iommu_configure_id(struct device *dev, const u32 *input_id)
+{ return -ENODEV; }
 #endif
 
 static int nc_dma_get_range(struct device *dev, u64 *size)
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index e166916eb9db..5924421075f6 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -9,6 +9,7 @@ 
 #include <linux/kernel.h>
 #include <linux/acpi.h>
 #include <linux/acpi_iort.h>
+#include <linux/iommu.h>
 #include <linux/signal.h>
 #include <linux/kthread.h>
 #include <linux/dmi.h>
@@ -1519,6 +1520,58 @@  int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
 	return ret >= 0 ? 0 : ret;
 }
 
+int acpi_iommu_fwspec_init(struct device *dev, u32 id,
+			   struct fwnode_handle *fwnode,
+			   const struct iommu_ops *ops)
+{
+	int ret = iommu_fwspec_init(dev, fwnode, ops);
+
+	if (!ret)
+		ret = iommu_fwspec_add_ids(dev, &id, 1);
+
+	return ret;
+}
+
+static inline const struct iommu_ops *acpi_iommu_fwspec_ops(struct device *dev)
+{
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+	return fwspec ? fwspec->ops : NULL;
+}
+
+static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev,
+						       const u32 *id_in)
+{
+	int err;
+	const struct iommu_ops *ops;
+
+	/*
+	 * If we already translated the fwspec there is nothing left to do,
+	 * return the iommu_ops.
+	 */
+	ops = acpi_iommu_fwspec_ops(dev);
+	if (ops)
+		return ops;
+
+	err = iort_iommu_configure_id(dev, id_in);
+
+	/*
+	 * If we have reason to believe the IOMMU driver missed the initial
+	 * add_device callback for dev, replay it to get things in order.
+	 */
+	if (!err && dev->bus && !device_iommu_mapped(dev))
+		err = iommu_probe_device(dev);
+
+	/* Ignore all other errors apart from EPROBE_DEFER */
+	if (err == -EPROBE_DEFER) {
+		return ERR_PTR(err);
+	} else if (err) {
+		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
+		return NULL;
+	}
+	return acpi_iommu_fwspec_ops(dev);
+}
+
 /**
  * acpi_dma_configure_id - Set-up DMA configuration for the device.
  * @dev: The pointer to the device
@@ -1538,7 +1591,7 @@  int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
 
 	acpi_arch_dma_setup(dev, &dma_addr, &size);
 
-	iommu = iort_iommu_configure_id(dev, input_id);
+	iommu = acpi_iommu_configure_id(dev, input_id);
 	if (PTR_ERR(iommu) == -EPROBE_DEFER)
 		return -EPROBE_DEFER;