[PATCH v4 09/10] fwctl/bnxt: Support communicating with bnxt fw

[Jason Gunthorpe <jgg@nvidia.com>]

From: Andy Gospodarek <gospo@broadcom.com>

This patch adds basic support for the fwctl infrastructure.  With the
approriate tool, the most basic RPC to the bnxt_en firmware can be
called.

Signed-off-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
 drivers/fwctl/Kconfig       |   9 ++
 drivers/fwctl/Makefile      |   1 +
 drivers/fwctl/bnxt/Makefile |   4 +
 drivers/fwctl/bnxt/bnxt.c   | 167 ++++++++++++++++++++++++++++++++++++
 include/uapi/fwctl/bnxt.h   |  27 ++++++
 include/uapi/fwctl/fwctl.h  |   1 +
 6 files changed, 209 insertions(+)
 create mode 100644 drivers/fwctl/bnxt/Makefile
 create mode 100644 drivers/fwctl/bnxt/bnxt.c
 create mode 100644 include/uapi/fwctl/bnxt.h

diff --git a/drivers/fwctl/Kconfig b/drivers/fwctl/Kconfig
index f802cf5d4951e8..0a542a247303d7 100644
--- a/drivers/fwctl/Kconfig
+++ b/drivers/fwctl/Kconfig
@@ -9,6 +9,15 @@ menuconfig FWCTL
 	  fit neatly into an existing subsystem.
 
 if FWCTL
+config FWCTL_BNXT
+	tristate "bnxt control fwctl driver"
+	depends on BNXT
+	help
+	  BNXT provides interface for the user process to access the debug and
+	  configuration registers of the Broadcom NIC hardware family
+
+	  If you don't know what to do here, say N.
+
 config FWCTL_MLX5
 	tristate "mlx5 ConnectX control fwctl driver"
 	depends on MLX5_CORE
diff --git a/drivers/fwctl/Makefile b/drivers/fwctl/Makefile
index 1c535f694d7fe4..5fb289243286ae 100644
--- a/drivers/fwctl/Makefile
+++ b/drivers/fwctl/Makefile
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_FWCTL) += fwctl.o
+obj-$(CONFIG_FWCTL_BNXT) += bnxt/
 obj-$(CONFIG_FWCTL_MLX5) += mlx5/
 
 fwctl-y += main.o
diff --git a/drivers/fwctl/bnxt/Makefile b/drivers/fwctl/bnxt/Makefile
new file mode 100644
index 00000000000000..57c76e0e0c9ca7
--- /dev/null
+++ b/drivers/fwctl/bnxt/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_FWCTL_BNXT) += bnxt_fwctl.o
+
+bnxt_fwctl-y += bnxt.o
diff --git a/drivers/fwctl/bnxt/bnxt.c b/drivers/fwctl/bnxt/bnxt.c
new file mode 100644
index 00000000000000..d2b9a64a1402bf
--- /dev/null
+++ b/drivers/fwctl/bnxt/bnxt.c
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2024, Broadcom Corporation
+ */
+#include <linux/fwctl.h>
+#include <linux/auxiliary_bus.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <uapi/fwctl/bnxt.h>
+
+/* FIXME need a include/linux header for the aux related definitions */
+#include <../../../drivers/net/ethernet/broadcom/bnxt/bnxt.h>
+#include <../../../drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h>
+
+struct bnxtctl_uctx {
+	struct fwctl_uctx uctx;
+	u32 uctx_caps;
+};
+
+struct bnxtctl_dev {
+	struct fwctl_device fwctl;
+	struct bnxt_aux_priv *aux_priv;
+};
+
+DEFINE_FREE(bnxtctl, struct bnxtctl_dev *, if (_T) fwctl_put(&_T->fwctl))
+
+static int bnxtctl_open_uctx(struct fwctl_uctx *uctx)
+{
+	struct bnxtctl_uctx *bnxtctl_uctx =
+		container_of(uctx, struct bnxtctl_uctx, uctx);
+
+	bnxtctl_uctx->uctx_caps = BIT(FWCTL_BNXT_QUERY_COMMANDS) |
+				  BIT(FWCTL_BNXT_SEND_COMMAND);
+	return 0;
+}
+
+static void bnxtctl_close_uctx(struct fwctl_uctx *uctx)
+{
+}
+
+static void *bnxtctl_info(struct fwctl_uctx *uctx, size_t *length)
+{
+	struct bnxtctl_uctx *bnxtctl_uctx =
+		container_of(uctx, struct bnxtctl_uctx, uctx);
+	struct fwctl_info_bnxt *info;
+
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return ERR_PTR(-ENOMEM);
+
+	info->uctx_caps = bnxtctl_uctx->uctx_caps;
+
+	*length = sizeof(*info);
+	return info;
+}
+
+/*
+ * bnxt_fw_msg->msg has the whole command
+ * the start of message is of type struct input
+ * struct input {
+ *         __le16  req_type;
+ *         __le16  cmpl_ring;
+ *         __le16  seq_id;
+ *         __le16  target_id;
+ *         __le64  resp_addr;
+ * };
+ * so the hwrm op should be (struct input *)(hwrm_in->msg)->req_type
+ */
+static bool bnxtctl_validate_rpc(struct fwctl_uctx *uctx,
+				 struct bnxt_fw_msg *hwrm_in)
+{
+	struct input *req = (struct input *)hwrm_in->msg;
+
+	switch (req->req_type) {
+	case HWRM_VER_GET:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static void *bnxtctl_fw_rpc(struct fwctl_uctx *uctx, enum fwctl_rpc_scope scope,
+			    void *in, size_t in_len, size_t *out_len)
+{
+	struct bnxtctl_dev *bnxtctl =
+		container_of(uctx->fwctl, struct bnxtctl_dev, fwctl);
+	struct bnxt_aux_priv *bnxt_aux_priv = bnxtctl->aux_priv;
+	/* FIXME: Check me */
+	struct bnxt_fw_msg rpc_in = {
+		// FIXME: does bnxt_send_msg() copy?
+		.msg = in,
+		.msg_len = in_len,
+		.resp = in,
+		// FIXME: Dynamic memory for out_len
+		.resp_max_len = in_len,
+	};
+	int rc;
+
+	if (!bnxtctl_validate_rpc(uctx, &rpc_in))
+		return ERR_PTR(-EPERM);
+
+	rc = bnxt_send_msg(bnxt_aux_priv->edev, &rpc_in);
+	if (!rc)
+		return ERR_PTR(-EOPNOTSUPP);
+	return in;
+}
+
+static const struct fwctl_ops bnxtctl_ops = {
+	.device_type = FWCTL_DEVICE_TYPE_BNXT,
+	.uctx_size = sizeof(struct bnxtctl_uctx),
+	.open_uctx = bnxtctl_open_uctx,
+	.close_uctx = bnxtctl_close_uctx,
+	.info = bnxtctl_info,
+	.fw_rpc = bnxtctl_fw_rpc,
+};
+
+static int bnxtctl_probe(struct auxiliary_device *adev,
+			 const struct auxiliary_device_id *id)
+{
+	struct bnxt_aux_priv *aux_priv =
+		container_of(adev, struct bnxt_aux_priv, aux_dev);
+	struct bnxtctl_dev *bnxtctl __free(bnxtctl) =
+		fwctl_alloc_device(&aux_priv->edev->pdev->dev, &bnxtctl_ops,
+				   struct bnxtctl_dev, fwctl);
+	int rc;
+
+	if (!bnxtctl)
+		return -ENOMEM;
+
+	bnxtctl->aux_priv = aux_priv;
+
+	rc = fwctl_register(&bnxtctl->fwctl);
+	if (rc)
+		return rc;
+
+	auxiliary_set_drvdata(adev, no_free_ptr(bnxtctl));
+	return 0;
+}
+
+static void bnxtctl_remove(struct auxiliary_device *adev)
+{
+	struct bnxtctl_dev *ctldev = auxiliary_get_drvdata(adev);
+
+	fwctl_unregister(&ctldev->fwctl);
+	fwctl_put(&ctldev->fwctl);
+}
+
+static const struct auxiliary_device_id bnxtctl_id_table[] = {
+	{ .name = "bnxt_en.fwctl", },
+	{},
+};
+MODULE_DEVICE_TABLE(auxiliary, bnxtctl_id_table);
+
+static struct auxiliary_driver bnxtctl_driver = {
+	.name = "bnxt_fwctl",
+	.probe = bnxtctl_probe,
+	.remove = bnxtctl_remove,
+	.id_table = bnxtctl_id_table,
+};
+
+module_auxiliary_driver(bnxtctl_driver);
+
+MODULE_IMPORT_NS(BNXT);
+MODULE_IMPORT_NS(FWCTL);
+MODULE_DESCRIPTION("BNXT fwctl driver");
+MODULE_AUTHOR("Broadcom Corporation");
+MODULE_LICENSE("GPL");
diff --git a/include/uapi/fwctl/bnxt.h b/include/uapi/fwctl/bnxt.h
new file mode 100644
index 00000000000000..ea47fdbbf6ea3e
--- /dev/null
+++ b/include/uapi/fwctl/bnxt.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (c) 2024, Broadcom Corporation
+ *
+ */
+#ifndef _UAPI_FWCTL_BNXT_H_
+#define _UAPI_FWCTL_BNXT_H_
+
+#include <linux/types.h>
+
+enum fwctl_bnxt_commands {
+	FWCTL_BNXT_QUERY_COMMANDS = 0,
+	FWCTL_BNXT_SEND_COMMAND,
+};
+
+/**
+ * struct fwctl_info_bnxt - ioctl(FWCTL_INFO) out_device_data
+ * @uctx_caps: The command capabilities driver accepts.
+ *
+ * Return basic information about the FW interface available.
+ */
+struct fwctl_info_bnxt {
+	__u32 uctx_caps;
+	__u32 reserved;
+};
+
+#endif
diff --git a/include/uapi/fwctl/fwctl.h b/include/uapi/fwctl/fwctl.h
index 0790b8291ee1bd..518f054f02d2d8 100644
--- a/include/uapi/fwctl/fwctl.h
+++ b/include/uapi/fwctl/fwctl.h
@@ -43,6 +43,7 @@ enum {
 enum fwctl_device_type {
 	FWCTL_DEVICE_TYPE_ERROR = 0,
 	FWCTL_DEVICE_TYPE_MLX5 = 1,
+	FWCTL_DEVICE_TYPE_BNXT = 3,
 };
 
 /**
-- 
2.43.0