[dpdk-dev] [PATCH v4 06/10] bus/mlx5_pci: add mlx5 PCI bus

[Parav Pandit]

Add mlx5 PCI bus which enables multiple mlx5 drivers to bind to single
pci device.

Signed-off-by: Parav Pandit <parav at mellanox.com>
Acked-by: Matan Azrad <matan at mellanox.com>
---
Changelog:
v2->v3:
 - Addressed comments from Thomas and Asaf
 - Moved pci_driver structure instance as first in driver
 - Removed white spaces at the end of line in diagram
 - Address comments from Matan
 - Removed CONFIG_RTE_LIBRTE_MLX5_PCI_BUS from config files
 - Changed alignedment to mlx5 specific aligment instead of standard
   DPDK
 - Using uint32_t instead of mlx5_class enum
v1->v2:
 - Address comments from Thomas and Gaetan
 - Inheriting ret_pci_driver instead of rte_driver
 - Added design and description of the mlx5_pci bus
---
 drivers/bus/meson.build                       |  2 +-
 drivers/bus/mlx5_pci/Makefile                 | 38 +++++++++
 drivers/bus/mlx5_pci/meson.build              | 19 +++++
 drivers/bus/mlx5_pci/mlx5_pci_bus.c           | 14 ++++
 drivers/bus/mlx5_pci/rte_bus_mlx5_pci.h       | 84 +++++++++++++++++++
 .../bus/mlx5_pci/rte_bus_mlx5_pci_version.map |  5 ++
 6 files changed, 161 insertions(+), 1 deletion(-)
 create mode 100644 drivers/bus/mlx5_pci/Makefile
 create mode 100644 drivers/bus/mlx5_pci/meson.build
 create mode 100644 drivers/bus/mlx5_pci/mlx5_pci_bus.c
 create mode 100644 drivers/bus/mlx5_pci/rte_bus_mlx5_pci.h
 create mode 100644 drivers/bus/mlx5_pci/rte_bus_mlx5_pci_version.map

diff --git a/drivers/bus/meson.build b/drivers/bus/meson.build
index 80de2d91d..b1381838d 100644
--- a/drivers/bus/meson.build
+++ b/drivers/bus/meson.build
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright(c) 2017 Intel Corporation
 
-drivers = ['dpaa', 'fslmc', 'ifpga', 'pci', 'vdev', 'vmbus']
+drivers = ['dpaa', 'fslmc', 'ifpga', 'pci', 'mlx5_pci', 'vdev', 'vmbus']
 std_deps = ['eal']
 config_flag_fmt = 'RTE_LIBRTE_ at 0@_BUS'
 driver_name_fmt = 'rte_bus_ at 0@'
diff --git a/drivers/bus/mlx5_pci/Makefile b/drivers/bus/mlx5_pci/Makefile
new file mode 100644
index 000000000..de4ccd83f
--- /dev/null
+++ b/drivers/bus/mlx5_pci/Makefile
@@ -0,0 +1,38 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright 2020 Mellanox Technologies, Ltd
+
+include $(RTE_SDK)/mk/rte.vars.mk
+
+#
+# library name
+#
+LIB = librte_bus_mlx5_pci.a
+
+CFLAGS += -O3 -Wall -Wextra
+CFLAGS += $(WERROR_FLAGS)
+CFLAGS += -Wno-strict-prototypes
+CFLAGS += -I$(RTE_SDK)/drivers/common/mlx5
+CFLAGS += -I$(BUILDDIR)/drivers/common/mlx5
+CFLAGS += -I$(RTE_SDK)/drivers/common/mlx5/linux
+CFLAGS += -I$(RTE_SDK)/drivers/bus/pci
+LDLIBS += -lrte_eal
+LDLIBS += -lrte_common_mlx5
+LDLIBS += -lrte_pci -lrte_bus_pci
+
+# versioning export map
+EXPORT_MAP := rte_bus_mlx5_pci_version.map
+
+SRCS-y += mlx5_pci_bus.c
+
+# DEBUG which is usually provided on the command-line may enable
+# CONFIG_RTE_LIBRTE_MLX5_DEBUG.
+ifeq ($(DEBUG),1)
+CONFIG_RTE_LIBRTE_MLX5_DEBUG := y
+endif
+
+#
+# Export include files
+#
+SYMLINK-y-include += rte_bus_mlx5_pci.h
+
+include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/drivers/bus/mlx5_pci/meson.build b/drivers/bus/mlx5_pci/meson.build
new file mode 100644
index 000000000..64a17cbad
--- /dev/null
+++ b/drivers/bus/mlx5_pci/meson.build
@@ -0,0 +1,19 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2020 Mellanox Technologies Ltd
+
+deps += ['pci', 'bus_pci', 'common_mlx5']
+install_headers('rte_bus_mlx5_pci.h')
+sources = files('mlx5_pci_bus.c')
+
+cflags_options = [
+	'-std=c11',
+	'-Wno-strict-prototypes',
+	'-D_BSD_SOURCE',
+	'-D_DEFAULT_SOURCE',
+	'-D_XOPEN_SOURCE=600'
+]
+foreach option:cflags_options
+	if cc.has_argument(option)
+		cflags += option
+	endif
+endforeach
diff --git a/drivers/bus/mlx5_pci/mlx5_pci_bus.c b/drivers/bus/mlx5_pci/mlx5_pci_bus.c
new file mode 100644
index 000000000..66db3c7b0
--- /dev/null
+++ b/drivers/bus/mlx5_pci/mlx5_pci_bus.c
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2020 Mellanox Technologies, Ltd
+ */
+
+#include "rte_bus_mlx5_pci.h"
+
+static TAILQ_HEAD(mlx5_pci_bus_drv_head, rte_mlx5_pci_driver) drv_list =
+				TAILQ_HEAD_INITIALIZER(drv_list);
+
+void
+rte_mlx5_pci_driver_register(struct rte_mlx5_pci_driver *driver)
+{
+	TAILQ_INSERT_TAIL(&drv_list, driver, next);
+}
diff --git a/drivers/bus/mlx5_pci/rte_bus_mlx5_pci.h b/drivers/bus/mlx5_pci/rte_bus_mlx5_pci.h
new file mode 100644
index 000000000..9f8d22e2b
--- /dev/null
+++ b/drivers/bus/mlx5_pci/rte_bus_mlx5_pci.h
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2020 Mellanox Technologies, Ltd
+ */
+
+#ifndef _RTE_BUS_MLX5_PCI_H_
+#define _RTE_BUS_MLX5_PCI_H_
+
+/**
+ * @file
+ *
+ * RTE Mellanox PCI Bus Interface
+ * Mellanox ConnectX PCI device supports multiple class (net/vdpa/regex)
+ * devices. This bus enables creating such multiple class of devices on a
+ * single PCI device by allowing to bind multiple class specific device
+ * driver to attach to mlx5_pci bus driver.
+ *
+ * -----------    ------------    -----------------
+ * |   mlx5  |    |   mlx5   |    |   mlx5        |
+ * | net pmd |    | vdpa pmd |    | new class pmd |
+ * -----------    ------------    -----------------
+ *      \              |                /
+ *       \             |               /
+ *        \       -------------       /
+ *         \______|   mlx5    |_____ /
+ *                |   pci bus |
+ *                -------------
+ *                     |
+ *                 -----------
+ *                 |   mlx5  |
+ *                 | pci dev |
+ *                 -----------
+ *
+ * - mlx5 pci bus driver binds to mlx5 PCI devices defined by PCI
+ *   ID table of all related mlx5 PCI devices.
+ * - mlx5 class driver such as net, vdpa, regex PMD defines its
+ *   specific PCI ID table and mlx5 bus driver probes matching
+ *   class drivers.
+ * - mlx5 pci bus driver is cental place that validates supported
+ *   class combinations.
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+#include <rte_pci.h>
+#include <rte_bus_pci.h>
+
+#include <mlx5_common.h>
+
+/**
+ * A structure describing a mlx5 pci driver.
+ */
+struct rte_mlx5_pci_driver {
+	struct rte_pci_driver pci_driver;	/**< Inherit core pci driver. */
+	uint32_t dev_class;	/**< Class of this driver, enum mlx5_class */
+	TAILQ_ENTRY(rte_mlx5_pci_driver) next;
+};
+
+/**
+ * Register a mlx5_pci device driver.
+ *
+ * @param driver
+ *   A pointer to a rte_mlx5_pci_driver structure describing the driver
+ *   to be registered.
+ */
+__rte_internal
+void
+rte_mlx5_pci_driver_register(struct rte_mlx5_pci_driver *driver);
+
+#define RTE_PMD_REGISTER_MLX5_PCI(nm, drv) \
+	static const char *mlx5_pci_drvinit_fn_ ## nm; \
+	RTE_INIT(mlx5_pci_drvinit_fn_ ##drv) \
+	{ \
+		(drv).driver.name = RTE_STR(nm); \
+		rte_mlx5_pci_driver_register(&drv); \
+	} \
+	RTE_PMD_EXPORT_NAME(nm, __COUNTER__)
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* _RTE_BUS_MLX5_PCI_H_ */
diff --git a/drivers/bus/mlx5_pci/rte_bus_mlx5_pci_version.map b/drivers/bus/mlx5_pci/rte_bus_mlx5_pci_version.map
new file mode 100644
index 000000000..4cfd3db10
--- /dev/null
+++ b/drivers/bus/mlx5_pci/rte_bus_mlx5_pci_version.map
@@ -0,0 +1,5 @@
+INTERNAL {
+	global:
+
+	rte_mlx5_pci_driver_register;
+};
-- 
2.26.2