[dpdk-dev] [PATCH v11 03/13] bus: add probing

[Thomas Monjalon]

From: Shreyansh Jain <shreyansh.jain at nxp.com>

Bus implementations can implement a probe handler to match the devices
scanned against the drivers registered.

Signed-off-by: Shreyansh Jain <shreyansh.jain at nxp.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit at intel.com>
Signed-off-by: Thomas Monjalon <thomas.monjalon at 6wind.com>
---
 lib/librte_eal/bsdapp/eal/eal.c                 |  4 ++++
 lib/librte_eal/bsdapp/eal/rte_eal_version.map   |  1 +
 lib/librte_eal/common/eal_common_bus.c          | 20 ++++++++++++++++++++
 lib/librte_eal/common/include/rte_bus.h         | 23 +++++++++++++++++++++++
 lib/librte_eal/linuxapp/eal/eal.c               |  4 ++++
 lib/librte_eal/linuxapp/eal/rte_eal_version.map |  1 +
 6 files changed, 53 insertions(+)

diff --git a/lib/librte_eal/bsdapp/eal/eal.c b/lib/librte_eal/bsdapp/eal/eal.c
index be5d295..534aeea 100644
--- a/lib/librte_eal/bsdapp/eal/eal.c
+++ b/lib/librte_eal/bsdapp/eal/eal.c
@@ -612,6 +612,10 @@ rte_eal_init(int argc, char **argv)
 	rte_eal_mp_remote_launch(sync_func, NULL, SKIP_MASTER);
 	rte_eal_mp_wait_lcore();
 
+	/* Probe all the buses and devices/drivers on them */
+	if (rte_bus_probe())
+		rte_panic("Cannot probe devices\n");
+
 	/* Probe & Initialize PCI devices */
 	if (rte_eal_pci_probe())
 		rte_panic("Cannot probe PCI\n");
diff --git a/lib/librte_eal/bsdapp/eal/rte_eal_version.map b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
index 931afeb..2cf1ac8 100644
--- a/lib/librte_eal/bsdapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
@@ -179,6 +179,7 @@ DPDK_17.02 {
 	global:
 
 	rte_bus_dump;
+	rte_bus_probe;
 	rte_bus_register;
 	rte_bus_scan;
 	rte_bus_unregister;
diff --git a/lib/librte_eal/common/eal_common_bus.c b/lib/librte_eal/common/eal_common_bus.c
index ef10390..4638e78 100644
--- a/lib/librte_eal/common/eal_common_bus.c
+++ b/lib/librte_eal/common/eal_common_bus.c
@@ -49,6 +49,7 @@ rte_bus_register(struct rte_bus *bus)
 	RTE_VERIFY(bus->name && strlen(bus->name));
 	/* A bus should mandatorily have the scan implemented */
 	RTE_VERIFY(bus->scan);
+	RTE_VERIFY(bus->probe);
 
 	TAILQ_INSERT_TAIL(&rte_bus_list, bus, next);
 	RTE_LOG(DEBUG, EAL, "Registered [%s] bus.\n", bus->name);
@@ -80,6 +81,25 @@ rte_bus_scan(void)
 	return 0;
 }
 
+/* Probe all devices of all buses */
+int
+rte_bus_probe(void)
+{
+	int ret;
+	struct rte_bus *bus;
+
+	TAILQ_FOREACH(bus, &rte_bus_list, next) {
+		ret = bus->probe();
+		if (ret) {
+			RTE_LOG(ERR, EAL, "Bus (%s) probe failed.\n",
+				bus->name);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
 /* Dump information of a single bus */
 static int
 bus_dump_one(FILE *f, struct rte_bus *bus)
diff --git a/lib/librte_eal/common/include/rte_bus.h b/lib/librte_eal/common/include/rte_bus.h
index b01930a..7c36969 100644
--- a/lib/librte_eal/common/include/rte_bus.h
+++ b/lib/librte_eal/common/include/rte_bus.h
@@ -70,12 +70,25 @@ TAILQ_HEAD(rte_bus_list, rte_bus);
 typedef int (*rte_bus_scan_t)(void);
 
 /**
+ * Implementation specific probe function which is responsible for linking
+ * devices on that bus with applicable drivers.
+ *
+ * This is called while iterating over each registered bus.
+ *
+ * @return
+ *	0 for successful probe
+ *	!0 for any error while probing
+ */
+typedef int (*rte_bus_probe_t)(void);
+
+/**
  * A structure describing a generic bus.
  */
 struct rte_bus {
 	TAILQ_ENTRY(rte_bus) next;   /**< Next bus object in linked list */
 	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 */
 };
 
 /**
@@ -106,6 +119,16 @@ void rte_bus_unregister(struct rte_bus *bus);
 int rte_bus_scan(void);
 
 /**
+ * For each device on the buses, perform a driver 'match' and call the
+ * driver-specific probe for device initialization.
+ *
+ * @return
+ *	 0 for successful match/probe
+ *	!0 otherwise
+ */
+int rte_bus_probe(void);
+
+/**
  * Dump information of all the buses registered with EAL.
  *
  * @param f
diff --git a/lib/librte_eal/linuxapp/eal/eal.c b/lib/librte_eal/linuxapp/eal/eal.c
index 1d2a16a..bf6b818 100644
--- a/lib/librte_eal/linuxapp/eal/eal.c
+++ b/lib/librte_eal/linuxapp/eal/eal.c
@@ -884,6 +884,10 @@ rte_eal_init(int argc, char **argv)
 	rte_eal_mp_remote_launch(sync_func, NULL, SKIP_MASTER);
 	rte_eal_mp_wait_lcore();
 
+	/* Probe all the buses and devices/drivers on them */
+	if (rte_bus_probe())
+		rte_panic("Cannot probe devices\n");
+
 	/* Probe & Initialize PCI devices */
 	if (rte_eal_pci_probe())
 		rte_panic("Cannot probe PCI\n");
diff --git a/lib/librte_eal/linuxapp/eal/rte_eal_version.map b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
index c238381..3c68ff5 100644
--- a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
@@ -183,6 +183,7 @@ DPDK_17.02 {
 	global:
 
 	rte_bus_dump;
+	rte_bus_probe;
 	rte_bus_register;
 	rte_bus_scan;
 	rte_bus_unregister;
-- 
2.7.0