[dpdk-dev] [PATCH 03/10] bus: get iommu class

[Santosh Shukla]

Currently there is noway to detect iova address mapping scheme for a
device on the bus.

API(rte_bus_get_iommu_class) helps to automatically detect and select
appropriate iova mapping scheme for iommu capable device on that bus.

Signed-off-by: Santosh Shukla <santosh.shukla at caviumnetworks.com>
Signed-off-by: Jerin Jacob <jerin.jacob at caviumnetworks.com>
---
 lib/librte_eal/bsdapp/eal/rte_eal_version.map   |  1 +
 lib/librte_eal/common/eal_common_bus.c          | 23 +++++++++++++++++++++++
 lib/librte_eal/common/eal_common_pci.c          |  1 +
 lib/librte_eal/common/include/rte_bus.h         | 21 +++++++++++++++++++++
 lib/librte_eal/linuxapp/eal/rte_eal_version.map |  1 +
 5 files changed, 47 insertions(+)

diff --git a/lib/librte_eal/bsdapp/eal/rte_eal_version.map b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
index a9cc3a67e..0beadacfb 100644
--- a/lib/librte_eal/bsdapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
@@ -198,5 +198,6 @@ DPDK_17.08 {
 	global:
 
 	rte_pci_get_iommu_class;
+	rte_bus_get_iommu_class;
 
 } DPDK_17.05;
diff --git a/lib/librte_eal/common/eal_common_bus.c b/lib/librte_eal/common/eal_common_bus.c
index 8f9baf8b8..04398275d 100644
--- a/lib/librte_eal/common/eal_common_bus.c
+++ b/lib/librte_eal/common/eal_common_bus.c
@@ -145,3 +145,26 @@ rte_bus_dump(FILE *f)
 		}
 	}
 }
+
+/*
+ * Get iommu class of devices on the bus.
+ */
+enum rte_iova_mode
+rte_bus_get_iommu_class(void)
+{
+	int mode = RTE_IOVA_DC;
+	struct rte_bus *bus;
+
+	TAILQ_FOREACH(bus, &rte_bus_list, next) {
+
+		if (bus->get_iommu_class) {
+			mode |= bus->get_iommu_class();
+		}
+	}
+
+	if (mode != RTE_IOVA_VA) {
+		/* Mapping could be _DC or _PA. Use default IOVA mode */
+		mode = RTE_IOVA_PA;
+	}
+	return mode;
+}
diff --git a/lib/librte_eal/common/eal_common_pci.c b/lib/librte_eal/common/eal_common_pci.c
index 5ae520186..9d4ed7927 100644
--- a/lib/librte_eal/common/eal_common_pci.c
+++ b/lib/librte_eal/common/eal_common_pci.c
@@ -487,6 +487,7 @@ struct rte_pci_bus rte_pci_bus = {
 	.bus = {
 		.scan = rte_pci_scan,
 		.probe = rte_pci_probe,
+		.get_iommu_class = rte_pci_get_iommu_class,
 	},
 	.device_list = TAILQ_HEAD_INITIALIZER(rte_pci_bus.device_list),
 	.driver_list = TAILQ_HEAD_INITIALIZER(rte_pci_bus.driver_list),
diff --git a/lib/librte_eal/common/include/rte_bus.h b/lib/librte_eal/common/include/rte_bus.h
index 56eacd0c9..734f6f051 100644
--- a/lib/librte_eal/common/include/rte_bus.h
+++ b/lib/librte_eal/common/include/rte_bus.h
@@ -91,6 +91,16 @@ typedef int (*rte_bus_scan_t)(void);
  */
 typedef int (*rte_bus_probe_t)(void);
 
+
+/**
+ * Get iommu class of devices on the bus.
+ * Check that those devices are attached to iommu driver.
+ *
+ * @return
+ *      enum rte_iova_mode value.
+ */
+typedef enum rte_iova_mode (*rte_bus_get_iommu_class_t)(void);
+
 /**
  * A structure describing a generic bus.
  */
@@ -99,6 +109,7 @@ struct rte_bus {
 	const char *name;            /**< Name of the bus */
 	rte_bus_scan_t scan;         /**< Scan for devices attached to bus */
 	rte_bus_probe_t probe;       /**< Probe devices on bus */
+	rte_bus_get_iommu_class_t get_iommu_class; /**< Get iommu class */
 };
 
 /**
@@ -150,6 +161,16 @@ int rte_bus_probe(void);
  */
 void rte_bus_dump(FILE *f);
 
+
+/**
+ * Get iommu class of devices on the bus.
+ * Check that those devices are attached to iommu driver.
+ *
+ * @return
+ *	enum rte_iova_mode value.
+ */
+enum rte_iova_mode rte_bus_get_iommu_class(void);
+
 /**
  * Helper for Bus registration.
  * The constructor has higher priority than PMD constructors.
diff --git a/lib/librte_eal/linuxapp/eal/rte_eal_version.map b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
index 2cea7c272..6c016c82e 100644
--- a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
@@ -203,5 +203,6 @@ DPDK_17.08 {
 	global:
 
 	rte_pci_get_iommu_class;
+	rte_bus_get_iommu_class;
 
 } DPDK_17.05;
-- 
2.11.0