ACPI/IORT: Fix build error when IOMMU_SUPPORT is disabled

If IOMMU_SUPPORT is not enabled (and therefore IOMMU_API is not
selected), struct iommu_fwspec is an empty struct and
IOMMU_FWSPEC_PCI_RC_ATS is not defined, resulting in the following
compilation errors:

drivers/acpi/arm64/iort.c: In function iort_iommu_configure:
drivers/acpi/arm64/iort.c:1079:21: error: struct iommu_fwspec has no member named flag:
    dev->iommu_fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS;
                     ^~
drivers/acpi/arm64/iort.c:1079:32: error: IOMMU_FWSPEC_PCI_RC_ATS
undeclared (first use in this function)
    dev->iommu_fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS;
                                ^~~~~~~~~~~~~~~~~~~~~~~
drivers/acpi/arm64/iort.c:1079:32: note: each undeclared identifier is reported only once for each function it appears in

Move iort_iommu_configure() (and the helpers functions it relies on)
into CONFIG_IOMMU_API preprocessor guarded code so that when
CONFIG_IOMMU_SUPPORT is not enabled we prevent compiling code that is
basically equivalent to no-OP, fixing the build errors.

Cc: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/linux-arm-kernel/20190515034253.79348-1-wangkefeng.wang@huawei.com/
Fixes: 5702ee24182f ("ACPI/IORT: Check ATS capability in root complex nodes")
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 9058cb084b919c7ec8140792914ccfacfc9be295..b5390b4c9ade8431cee6e3cc483813f4e2be9e2a 100644 (file)
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -753,31 +753,6 @@ static int __maybe_unused __get_pci_rid(struct pci_dev *pdev, u16 alias,
        return 0;
 }
 
-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 inline bool iort_iommu_driver_enabled(u8 type)
-{
-       switch (type) {
-       case ACPI_IORT_NODE_SMMU_V3:
-               return IS_BUILTIN(CONFIG_ARM_SMMU_V3);
-       case ACPI_IORT_NODE_SMMU:
-               return IS_BUILTIN(CONFIG_ARM_SMMU);
-       default:
-               pr_warn("IORT node type %u does not describe an SMMU\n", type);
-               return false;
-       }
-}
-
 #ifdef CONFIG_IOMMU_API
 static struct acpi_iort_node *iort_get_msi_resv_iommu(struct device *dev)
 {
@@ -878,15 +853,39 @@ int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head)
 
        return (resv == its->its_count) ? resv : -ENODEV;
 }
-#else
-static inline const struct iommu_ops *iort_fwspec_iommu_ops(struct device *dev)
-{ return NULL; }
-static inline int iort_add_device_replay(const struct iommu_ops *ops,
-                                        struct device *dev)
-{ return 0; }
-int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head)
-{ return 0; }
-#endif
+
+static inline bool iort_iommu_driver_enabled(u8 type)
+{
+       switch (type) {
+       case ACPI_IORT_NODE_SMMU_V3:
+               return IS_BUILTIN(CONFIG_ARM_SMMU_V3);
+       case ACPI_IORT_NODE_SMMU:
+               return IS_BUILTIN(CONFIG_ARM_SMMU);
+       default:
+               pr_warn("IORT node type %u does not describe an SMMU\n", type);
+               return false;
+       }
+}
+
+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;
+
+       pci_rc = (struct acpi_iort_root_complex *)node->node_data;
+       return pci_rc->ats_attribute & ACPI_IORT_ATS_SUPPORTED;
+}
 
 static int iort_iommu_xlate(struct device *dev, struct acpi_iort_node *node,
                            u32 streamid)
@@ -933,6 +932,93 @@ static int iort_pci_iommu_init(struct pci_dev *pdev, u16 alias, void *data)
        return iort_iommu_xlate(info->dev, parent, streamid);
 }
 
+/**
+ * iort_iommu_configure - Set-up IOMMU configuration for a device.
+ *
+ * @dev: device to configure
+ *
+ * Returns: iommu_ops pointer on configuration success
+ *          NULL on configuration failure
+ */
+const struct iommu_ops *iort_iommu_configure(struct device *dev)
+{
+       struct acpi_iort_node *node, *parent;
+       const struct iommu_ops *ops;
+       u32 streamid = 0;
+       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 pci_bus *bus = to_pci_dev(dev)->bus;
+               struct iort_pci_alias_info info = { .dev = dev };
+
+               node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
+                                     iort_match_node_callback, &bus->dev);
+               if (!node)
+                       return NULL;
+
+               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;
+
+               node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
+                                     iort_match_node_callback, dev);
+               if (!node)
+                       return NULL;
+
+               do {
+                       parent = iort_node_map_platform_id(node, &streamid,
+                                                          IORT_IOMMU_TYPE,
+                                                          i++);
+
+                       if (parent)
+                               err = iort_iommu_xlate(dev, parent, streamid);
+               } while (parent && !err);
+       }
+
+       /*
+        * 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(ops, 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;
+}
+#else
+static inline const struct iommu_ops *iort_fwspec_iommu_ops(struct device *dev)
+{ return NULL; }
+static inline int iort_add_device_replay(const struct iommu_ops *ops,
+                                        struct device *dev)
+{ return 0; }
+int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head)
+{ return 0; }
+const struct iommu_ops *iort_iommu_configure(struct device *dev)
+{ return NULL; }
+#endif
+
 static int nc_dma_get_range(struct device *dev, u64 *size)
 {
        struct acpi_iort_node *node;
@@ -1031,90 +1117,6 @@ 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.
- *
- * @dev: device to configure
- *
- * Returns: iommu_ops pointer on configuration success
- *          NULL on configuration failure
- */
-const struct iommu_ops *iort_iommu_configure(struct device *dev)
-{
-       struct acpi_iort_node *node, *parent;
-       const struct iommu_ops *ops;
-       u32 streamid = 0;
-       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 pci_bus *bus = to_pci_dev(dev)->bus;
-               struct iort_pci_alias_info info = { .dev = dev };
-
-               node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
-                                     iort_match_node_callback, &bus->dev);
-               if (!node)
-                       return NULL;
-
-               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;
-
-               node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
-                                     iort_match_node_callback, dev);
-               if (!node)
-                       return NULL;
-
-               do {
-                       parent = iort_node_map_platform_id(node, &streamid,
-                                                          IORT_IOMMU_TYPE,
-                                                          i++);
-
-                       if (parent)
-                               err = iort_iommu_xlate(dev, parent, streamid);
-               } while (parent && !err);
-       }
-
-       /*
-        * 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(ops, 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;
-}
-
 static void __init acpi_iort_register_irq(int hwirq, const char *name,
                                          int trigger,
                                          struct resource *res)