[PATCH iwl-next 11/14] ixd: add basic driver framework for Intel(R) Control Plane Function

Larysa Zaremba
2025-04-08T12:48:53Z

Add module register and probe functionality. Add the required support
to register IXD PCI driver, as well as probe and remove call backs.
Enable the PCI device and request the kernel to reserve the memory
resources that will be used by the driver. Finally map the BAR0
address space.

For now, use devm_alloc() to allocate adapter, as it requires the least
amount of code. In a later commit, it will be replaced with a devlink
alternative.

Co-developed-by: Amritha Nambiar <amritha.nambiar@intel.com>
Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
---
.../device_drivers/ethernet/index.rst | 1 +
.../device_drivers/ethernet/intel/ixd.rst | 39 ++++++
drivers/net/ethernet/intel/Kconfig | 2 +
drivers/net/ethernet/intel/Makefile | 1 +
drivers/net/ethernet/intel/ixd/Kconfig | 13 ++
drivers/net/ethernet/intel/ixd/Makefile | 8 ++
drivers/net/ethernet/intel/ixd/ixd.h | 26 ++++
drivers/net/ethernet/intel/ixd/ixd_lan_regs.h | 28 ++++
drivers/net/ethernet/intel/ixd/ixd_main.c | 122 ++++++++++++++++++
9 files changed, 240 insertions(+)
create mode 100644 Documentation/networking/device_drivers/ethernet/intel/ixd.rst
create mode 100644 drivers/net/ethernet/intel/ixd/Kconfig
create mode 100644 drivers/net/ethernet/intel/ixd/Makefile
create mode 100644 drivers/net/ethernet/intel/ixd/ixd.h
create mode 100644 drivers/net/ethernet/intel/ixd/ixd_lan_regs.h
create mode 100644 drivers/net/ethernet/intel/ixd/ixd_main.c

diff --git a/Documentation/networking/device_drivers/ethernet/index.rst b/Documentation/networking/device_drivers/ethernet/index.rst
index 05d822b904b4..c2b1951fec84 100644
--- a/Documentation/networking/device_drivers/ethernet/index.rst
+++ b/Documentation/networking/device_drivers/ethernet/index.rst
@@ -37,6 +37,7 @@ Contents:
intel/igbvf
intel/ixgbe
intel/ixgbevf
+ intel/ixd
intel/i40e
intel/iavf
intel/ice
diff --git a/Documentation/networking/device_drivers/ethernet/intel/ixd.rst b/Documentation/networking/device_drivers/ethernet/intel/ixd.rst
new file mode 100644
index 000000000000..1387626e5d20
--- /dev/null
+++ b/Documentation/networking/device_drivers/ethernet/intel/ixd.rst
@@ -0,0 +1,39 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+==========================================================================
+iXD Linux* Base Driver for the Intel(R) Control Plane Function
+==========================================================================
+
+Intel iXD Linux driver.
+Copyright(C) 2025 Intel Corporation.
+
+.. contents::
+
+For questions related to hardware requirements, refer to the documentation
+supplied with your Intel adapter. All hardware requirements listed apply to use
+with Linux.
+
+
+Identifying Your Adapter
+========================
+For information on how to identify your adapter, and for the latest Intel
+network drivers, refer to the Intel Support website:
+http://www.intel.com/support
+
+
+Support
+=======
+For general information, go to the Intel support website at:
+http://www.intel.com/support/
+
+If an issue is identified with the released source code on a supported kernel
+with a supported adapter, email the specific information related to the issue
+to intel-wired-lan@lists.osuosl.org.
+
+
+Trademarks
+==========
+Intel is a trademark or registered trademark of Intel Corporation or its
+subsidiaries in the United States and/or other countries.
+
+* Other names and brands may be claimed as the property of others.
diff --git a/drivers/net/ethernet/intel/Kconfig b/drivers/net/ethernet/intel/Kconfig
index 5a331c1c76cb..d92b832a067a 100644
--- a/drivers/net/ethernet/intel/Kconfig
+++ b/drivers/net/ethernet/intel/Kconfig
@@ -392,4 +392,6 @@ config IGC_LEDS

source "drivers/net/ethernet/intel/idpf/Kconfig"

+source "drivers/net/ethernet/intel/ixd/Kconfig"
+
endif # NET_VENDOR_INTEL
diff --git a/drivers/net/ethernet/intel/Makefile b/drivers/net/ethernet/intel/Makefile
index 04c844ef4964..8de2222a0333 100644
--- a/drivers/net/ethernet/intel/Makefile
+++ b/drivers/net/ethernet/intel/Makefile
@@ -19,3 +19,4 @@ obj-$(CONFIG_IAVF) += iavf/
obj-$(CONFIG_FM10K) += fm10k/
obj-$(CONFIG_ICE) += ice/
obj-$(CONFIG_IDPF) += idpf/
+obj-$(CONFIG_IXD) += ixd/
diff --git a/drivers/net/ethernet/intel/ixd/Kconfig b/drivers/net/ethernet/intel/ixd/Kconfig
new file mode 100644
index 000000000000..3bf6e2407af6
--- /dev/null
+++ b/drivers/net/ethernet/intel/ixd/Kconfig
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# Copyright (C) 2025 Intel Corporation
+
+config IXD
+ tristate "Intel(R) Control Plane Function Support"
+ depends on PCI_MSI
+ select LIBETH
+ select LIBETH_PCI
+ help
+ This driver supports Intel(R) Control Plane PCI Function
+ of Intel E2100 and later IPUs and FNICs.
+ It facilitates a centralized control over multiple IDPF PFs/VFs/SFs
+ exposed by the same card.
diff --git a/drivers/net/ethernet/intel/ixd/Makefile b/drivers/net/ethernet/intel/ixd/Makefile
new file mode 100644
index 000000000000..3849bc240600
--- /dev/null
+++ b/drivers/net/ethernet/intel/ixd/Makefile
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# Copyright (C) 2025 Intel Corporation
+
+# Intel(R) Control Plane Function Linux Driver
+
+obj-$(CONFIG_IXD) += ixd.o
+
+ixd-y := ixd_main.o
diff --git a/drivers/net/ethernet/intel/ixd/ixd.h b/drivers/net/ethernet/intel/ixd/ixd.h
new file mode 100644
index 000000000000..b558803914f9
--- /dev/null
+++ b/drivers/net/ethernet/intel/ixd/ixd.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (C) 2025 Intel Corporation */
+
+#ifndef _IXD_H_
+#define _IXD_H_
+
+#include <net/libeth/pci.h>
+
+/**
+ * struct ixd_adapter - Data structure representing a CPF
+ * @hw: Device access data
+ */
+struct ixd_adapter {
+ struct libeth_mmio_info hw;
+};
+
+/**
+ * ixd_to_dev - Get the corresponding device struct from an adapter
+ * @adapter: PCI device driver-specific private data
+ */
+static inline struct device *ixd_to_dev(struct ixd_adapter *adapter)
+{
+ return &adapter->hw.pdev->dev;
+}
+
+#endif /* _IXD_H_ */
diff --git a/drivers/net/ethernet/intel/ixd/ixd_lan_regs.h b/drivers/net/ethernet/intel/ixd/ixd_lan_regs.h
new file mode 100644
index 000000000000..a991eaa8a2aa
--- /dev/null
+++ b/drivers/net/ethernet/intel/ixd/ixd_lan_regs.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (C) 2025 Intel Corporation */
+
+#ifndef _IXD_LAN_REGS_H_
+#define _IXD_LAN_REGS_H_
+
+/* Control Plane Function PCI ID */
+#define IXD_DEV_ID_CPF 0x1453
+
+/* Control Queue (Mailbox) */
+#define PF_FW_MBX_REG_LEN 4096
+#define PF_FW_MBX 0x08400000
+
+/* Reset registers */
+#define PFGEN_RTRIG_REG_LEN 2048
+#define PFGEN_RTRIG 0x08407000 /* Device resets */
+
+/**
+ * struct ixd_bar_region - BAR region description
+ * @offset: BAR region offset
+ * @size: BAR region size
+ */
+struct ixd_bar_region {
+ resource_size_t offset;
+ resource_size_t size;
+};
+
+#endif /* _IXD_LAN_REGS_H_ */
diff --git a/drivers/net/ethernet/intel/ixd/ixd_main.c b/drivers/net/ethernet/intel/ixd/ixd_main.c
new file mode 100644
index 000000000000..1f59db0b8fe7
--- /dev/null
+++ b/drivers/net/ethernet/intel/ixd/ixd_main.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2025 Intel Corporation */
+
+#include "ixd.h"
+#include "ixd_lan_regs.h"
+
+MODULE_DESCRIPTION("Intel(R) Control Plane Function Device Driver");
+MODULE_IMPORT_NS("LIBETH_PCI");
+MODULE_LICENSE("GPL");
+
+/**
+ * ixd_remove - remove a CPF PCI device
+ * @pdev: PCI device being removed
+ */
+static void ixd_remove(struct pci_dev *pdev)
+{
+ struct ixd_adapter *adapter = pci_get_drvdata(pdev);
+
+ libeth_pci_unmap_all_mmio_regions(&adapter->hw);
+ libeth_pci_deinit_dev(pdev);
+}
+
+/**
+ * ixd_shutdown - shut down a CPF PCI device
+ * @pdev: PCI device being shut down
+ */
+static void ixd_shutdown(struct pci_dev *pdev)
+{
+ ixd_remove(pdev);
+
+ if (system_state == SYSTEM_POWER_OFF)
+ pci_set_power_state(pdev, PCI_D3hot);
+}
+
+/**
+ * ixd_iomap_regions - iomap PCI BARs
+ * @adapter: adapter to map memory regions for
+ *
+ * Returns: %0 on success, negative on failure
+ */
+static int ixd_iomap_regions(struct ixd_adapter *adapter)
+{
+ const struct ixd_bar_region regions[] = {
+ {
+ .offset = PFGEN_RTRIG,
+ .size = PFGEN_RTRIG_REG_LEN,
+ },
+ {
+ .offset = PF_FW_MBX,
+ .size = PF_FW_MBX_REG_LEN,
+ },
+ };
+
+ for (int i = 0; i < ARRAY_SIZE(regions); i++) {
+ struct libeth_mmio_info *mmio_info = &adapter->hw;
+ bool map_ok;
+
+ map_ok = libeth_pci_map_mmio_region(mmio_info,
+ regions[i].offset,
+ regions[i].size);
+ if (!map_ok) {
+ dev_err(ixd_to_dev(adapter),
+ "Failed to map PCI device MMIO region\n");
+
+ libeth_pci_unmap_all_mmio_regions(mmio_info);
+ return -EIO;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * ixd_probe - probe a CPF PCI device
+ * @pdev: corresponding PCI device
+ * @ent: entry in ixd_pci_tbl
+ *
+ * Returns: %0 on success, negative errno code on failure
+ */
+static int ixd_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+ struct ixd_adapter *adapter;
+ int err;
+
+ adapter = devm_kzalloc(&pdev->dev, sizeof(*adapter), GFP_KERNEL);
+ if (!adapter)
+ return -ENOMEM;
+ adapter->hw.pdev = pdev;
+ INIT_LIST_HEAD(&adapter->hw.mmio_list);
+
+ err = libeth_pci_init_dev(pdev);
+ if (err)
+ return err;
+
+ pci_set_drvdata(pdev, adapter);
+
+ err = ixd_iomap_regions(adapter);
+ if (err)
+ goto deinit_dev;
+
+ return 0;
+
+deinit_dev:
+ libeth_pci_deinit_dev(pdev);
+
+ return err;
+}
+
+static const struct pci_device_id ixd_pci_tbl[] = {
+ { PCI_VDEVICE(INTEL, IXD_DEV_ID_CPF) },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, ixd_pci_tbl);
+
+static struct pci_driver ixd_driver = {
+ .name = KBUILD_MODNAME,
+ .id_table = ixd_pci_tbl,
+ .probe = ixd_probe,
+ .remove = ixd_remove,
+ .shutdown = ixd_shutdown,
+};
+module_pci_driver(ixd_driver);
--
2.47.0