i40evf: virtual channel interface

This PCI-E SR-IOV virtual function (VF) driver is dependant upon the
physical function (PF) driver (i40e) for nearly all of its hardware
configuration. Requests from the VF driver are passed to the PF using
the hardware's Admin Queue.

This patch contains the functionality for communicating with the PF
driver. Because of the delay inherent in this communications channel,
most of the replies from the PF driver are handled asynchronously. The
exceptions are the "send API version" and "get VF config" messages,
which busy-wait because they are done so early during init that
interrupts are not yet configured.
Signed-off-by: NMitch Williams <mitch.a.williams@intel.com>
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Tested-by: NSibai Li <sibai.li@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40evf/i40e_virtchnl.h

+/*******************************************************************************
+ *
+ * Intel Ethernet Controller XL710 Family Linux Virtual Function Driver
+ * Copyright(c) 2013 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Contact Information:
+ * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ ******************************************************************************/
+
+#ifndef _I40E_VIRTCHNL_H_
+#define _I40E_VIRTCHNL_H_
+
+#include "i40e_type.h"
+
+/* Description:
+ * This header file describes the VF-PF communication protocol used
+ * by the various i40e drivers.
+ *
+ * Admin queue buffer usage:
+ * desc->opcode is always i40e_aqc_opc_send_msg_to_pf
+ * flags, retval, datalen, and data addr are all used normally.
+ * Firmware copies the cookie fields when sending messages between the PF and
+ * VF, but uses all other fields internally. Due to this limitation, we
+ * must send all messages as "indirect", i.e. using an external buffer.
+ *
+ * All the vsi indexes are relative to the VF. Each VF can have maximum of
+ * three VSIs. All the queue indexes are relative to the VSI.  Each VF can
+ * have a maximum of sixteen queues for all of its VSIs.
+ *
+ * The PF is required to return a status code in v_retval for all messages
+ * except RESET_VF, which does not require any response. The return value is of
+ * i40e_status_code type, defined in the i40e_type.h.
+ *
+ * In general, VF driver initialization should roughly follow the order of these
+ * opcodes. The VF driver must first validate the API version of the PF driver,
+ * then request a reset, then get resources, then configure queues and
+ * interrupts. After these operations are complete, the VF driver may start
+ * its queues, optionally add MAC and VLAN filters, and process traffic.
+ */
+
+/* Opcodes for VF-PF communication. These are placed in the v_opcode field
+ * of the virtchnl_msg structure.
+ */
+enum i40e_virtchnl_ops {
+/* VF sends req. to pf for the following
+ * ops.
+ */
+	I40E_VIRTCHNL_OP_UNKNOWN = 0,
+	I40E_VIRTCHNL_OP_VERSION = 1, /* must ALWAYS be 1 */
+	I40E_VIRTCHNL_OP_RESET_VF,
+	I40E_VIRTCHNL_OP_GET_VF_RESOURCES,
+	I40E_VIRTCHNL_OP_CONFIG_TX_QUEUE,
+	I40E_VIRTCHNL_OP_CONFIG_RX_QUEUE,
+	I40E_VIRTCHNL_OP_CONFIG_VSI_QUEUES,
+	I40E_VIRTCHNL_OP_CONFIG_IRQ_MAP,
+	I40E_VIRTCHNL_OP_ENABLE_QUEUES,
+	I40E_VIRTCHNL_OP_DISABLE_QUEUES,
+	I40E_VIRTCHNL_OP_ADD_ETHER_ADDRESS,
+	I40E_VIRTCHNL_OP_DEL_ETHER_ADDRESS,
+	I40E_VIRTCHNL_OP_ADD_VLAN,
+	I40E_VIRTCHNL_OP_DEL_VLAN,
+	I40E_VIRTCHNL_OP_CONFIG_PROMISCUOUS_MODE,
+	I40E_VIRTCHNL_OP_GET_STATS,
+	I40E_VIRTCHNL_OP_FCOE,
+/* PF sends status change events to vfs using
+ * the following op.
+ */
+	I40E_VIRTCHNL_OP_EVENT,
+};
+
+/* Virtual channel message descriptor. This overlays the admin queue
+ * descriptor. All other data is passed in external buffers.
+ */
+
+struct i40e_virtchnl_msg {
+	u8 pad[8];			 /* AQ flags/opcode/len/retval fields */
+	enum i40e_virtchnl_ops v_opcode; /* avoid confusion with desc->opcode */
+	i40e_status v_retval;  /* ditto for desc->retval */
+	u32 vfid;			 /* used by PF when sending to VF */
+};
+
+/* Message descriptions and data structures.*/
+
+/* I40E_VIRTCHNL_OP_VERSION
+ * VF posts its version number to the PF. PF responds with its version number
+ * in the same format, along with a return code.
+ * Reply from PF has its major/minor versions also in param0 and param1.
+ * If there is a major version mismatch, then the VF cannot operate.
+ * If there is a minor version mismatch, then the VF can operate but should
+ * add a warning to the system log.
+ *
+ * This enum element MUST always be specified as == 1, regardless of other
+ * changes in the API. The PF must always respond to this message without
+ * error regardless of version mismatch.
+ */
+#define I40E_VIRTCHNL_VERSION_MAJOR		1
+#define I40E_VIRTCHNL_VERSION_MINOR		0
+struct i40e_virtchnl_version_info {
+	u32 major;
+	u32 minor;
+};
+
+/* I40E_VIRTCHNL_OP_RESET_VF
+ * VF sends this request to PF with no parameters
+ * PF does NOT respond! VF driver must delay then poll VFGEN_RSTAT register
+ * until reset completion is indicated. The admin queue must be reinitialized
+ * after this operation.
+ *
+ * When reset is complete, PF must ensure that all queues in all VSIs associated
+ * with the VF are stopped, all queue configurations in the HMC are set to 0,
+ * and all MAC and VLAN filters (except the default MAC address) on all VSIs
+ * are cleared.
+ */
+
+/* I40E_VIRTCHNL_OP_GET_VF_RESOURCES
+ * VF sends this request to PF with no parameters
+ * PF responds with an indirect message containing
+ * i40e_virtchnl_vf_resource and one or more
+ * i40e_virtchnl_vsi_resource structures.
+ */
+
+struct i40e_virtchnl_vsi_resource {
+	u16 vsi_id;
+	u16 num_queue_pairs;
+	enum i40e_vsi_type vsi_type;
+	u16 qset_handle;
+	u8 default_mac_addr[ETH_ALEN];
+};
+/* VF offload flags */
+#define I40E_VIRTCHNL_VF_OFFLOAD_L2	0x00000001
+#define I40E_VIRTCHNL_VF_OFFLOAD_FCOE	0x00000004
+#define I40E_VIRTCHNL_VF_OFFLOAD_VLAN	0x00010000
+
+struct i40e_virtchnl_vf_resource {
+	u16 num_vsis;
+	u16 num_queue_pairs;
+	u16 max_vectors;
+	u16 max_mtu;
+
+	u32 vf_offload_flags;
+	u32 max_fcoe_contexts;
+	u32 max_fcoe_filters;
+
+	struct i40e_virtchnl_vsi_resource vsi_res[1];
+};
+
+/* I40E_VIRTCHNL_OP_CONFIG_TX_QUEUE
+ * VF sends this message to set up parameters for one TX queue.
+ * External data buffer contains one instance of i40e_virtchnl_txq_info.
+ * PF configures requested queue and returns a status code.
+ */
+
+/* Tx queue config info */
+struct i40e_virtchnl_txq_info {
+	u16 vsi_id;
+	u16 queue_id;
+	u16 ring_len;		/* number of descriptors, multiple of 8 */
+	u16 headwb_enabled;
+	u64 dma_ring_addr;
+	u64 dma_headwb_addr;
+};
+
+/* I40E_VIRTCHNL_OP_CONFIG_RX_QUEUE
+ * VF sends this message to set up parameters for one RX queue.
+ * External data buffer contains one instance of i40e_virtchnl_rxq_info.
+ * PF configures requested queue and returns a status code.
+ */
+
+/* Rx queue config info */
+struct i40e_virtchnl_rxq_info {
+	u16 vsi_id;
+	u16 queue_id;
+	u32 ring_len;		/* number of descriptors, multiple of 32 */
+	u16 hdr_size;
+	u16 splithdr_enabled;
+	u32 databuffer_size;
+	u32 max_pkt_size;
+	u64 dma_ring_addr;
+	enum i40e_hmc_obj_rx_hsplit_0 rx_split_pos;
+};
+
+/* I40E_VIRTCHNL_OP_CONFIG_VSI_QUEUES
+ * VF sends this message to set parameters for all active TX and RX queues
+ * associated with the specified VSI.
+ * PF configures queues and returns status.
+ * If the number of queues specified is greater than the number of queues
+ * associated with the VSI, an error is returned and no queues are configured.
+ */
+struct i40e_virtchnl_queue_pair_info {
+	/* NOTE: vsi_id and queue_id should be identical for both queues. */
+	struct i40e_virtchnl_txq_info txq;
+	struct i40e_virtchnl_rxq_info rxq;
+};
+
+struct i40e_virtchnl_vsi_queue_config_info {
+	u16 vsi_id;
+	u16 num_queue_pairs;
+	struct i40e_virtchnl_queue_pair_info qpair[1];
+};
+
+/* I40E_VIRTCHNL_OP_CONFIG_IRQ_MAP
+ * VF uses this message to map vectors to queues.
+ * The rxq_map and txq_map fields are bitmaps used to indicate which queues
+ * are to be associated with the specified vector.
+ * The "other" causes are always mapped to vector 0.
+ * PF configures interrupt mapping and returns status.
+ */
+struct i40e_virtchnl_vector_map {
+	u16 vsi_id;
+	u16 vector_id;
+	u16 rxq_map;
+	u16 txq_map;
+	u16 rxitr_idx;
+	u16 txitr_idx;
+};
+
+struct i40e_virtchnl_irq_map_info {
+	u16 num_vectors;
+	struct i40e_virtchnl_vector_map vecmap[1];
+};
+
+/* I40E_VIRTCHNL_OP_ENABLE_QUEUES
+ * I40E_VIRTCHNL_OP_DISABLE_QUEUES
+ * VF sends these message to enable or disable TX/RX queue pairs.
+ * The queues fields are bitmaps indicating which queues to act upon.
+ * (Currently, we only support 16 queues per VF, but we make the field
+ * u32 to allow for expansion.)
+ * PF performs requested action and returns status.
+ */
+struct i40e_virtchnl_queue_select {
+	u16 vsi_id;
+	u16 pad;
+	u32 rx_queues;
+	u32 tx_queues;
+};
+
+/* I40E_VIRTCHNL_OP_ADD_ETHER_ADDRESS
+ * VF sends this message in order to add one or more unicast or multicast
+ * address filters for the specified VSI.
+ * PF adds the filters and returns status.
+ */
+
+/* I40E_VIRTCHNL_OP_DEL_ETHER_ADDRESS
+ * VF sends this message in order to remove one or more unicast or multicast
+ * filters for the specified VSI.
+ * PF removes the filters and returns status.
+ */
+
+struct i40e_virtchnl_ether_addr {
+	u8 addr[ETH_ALEN];
+	u8 pad[2];
+};
+
+struct i40e_virtchnl_ether_addr_list {
+	u16 vsi_id;
+	u16 num_elements;
+	struct i40e_virtchnl_ether_addr list[1];
+};
+
+/* I40E_VIRTCHNL_OP_ADD_VLAN
+ * VF sends this message to add one or more VLAN tag filters for receives.
+ * PF adds the filters and returns status.
+ * If a port VLAN is configured by the PF, this operation will return an
+ * error to the VF.
+ */
+
+/* I40E_VIRTCHNL_OP_DEL_VLAN
+ * VF sends this message to remove one or more VLAN tag filters for receives.
+ * PF removes the filters and returns status.
+ * If a port VLAN is configured by the PF, this operation will return an
+ * error to the VF.
+ */
+
+struct i40e_virtchnl_vlan_filter_list {
+	u16 vsi_id;
+	u16 num_elements;
+	u16 vlan_id[1];
+};
+
+/* I40E_VIRTCHNL_OP_CONFIG_PROMISCUOUS_MODE
+ * VF sends VSI id and flags.
+ * PF returns status code in retval.
+ * Note: we assume that broadcast accept mode is always enabled.
+ */
+struct i40e_virtchnl_promisc_info {
+	u16 vsi_id;
+	u16 flags;
+};
+
+#define I40E_FLAG_VF_UNICAST_PROMISC	0x00000001
+#define I40E_FLAG_VF_MULTICAST_PROMISC	0x00000002
+
+/* I40E_VIRTCHNL_OP_GET_STATS
+ * VF sends this message to request stats for the selected VSI. VF uses
+ * the i40e_virtchnl_queue_select struct to specify the VSI. The queue_id
+ * field is ignored by the PF.
+ *
+ * PF replies with struct i40e_eth_stats in an external buffer.
+ */
+
+/* I40E_VIRTCHNL_OP_EVENT
+ * PF sends this message to inform the VF driver of events that may affect it.
+ * No direct response is expected from the VF, though it may generate other
+ * messages in response to this one.
+ */
+enum i40e_virtchnl_event_codes {
+	I40E_VIRTCHNL_EVENT_UNKNOWN = 0,
+	I40E_VIRTCHNL_EVENT_LINK_CHANGE,
+	I40E_VIRTCHNL_EVENT_RESET_IMPENDING,
+	I40E_VIRTCHNL_EVENT_PF_DRIVER_CLOSE,
+};
+#define I40E_PF_EVENT_SEVERITY_INFO		0
+#define I40E_PF_EVENT_SEVERITY_CERTAIN_DOOM	255
+
+struct i40e_virtchnl_pf_event {
+	enum i40e_virtchnl_event_codes event;
+	union {
+		struct {
+			enum i40e_aq_link_speed link_speed;
+			bool link_status;
+		} link_event;
+	} event_data;
+
+	int severity;
+};
+
+/* The following are TBD, not necessary for LAN functionality.
+ * I40E_VIRTCHNL_OP_FCOE
+ */
+
+/* VF reset states - these are written into the RSTAT register:
+ * I40E_VFGEN_RSTAT1 on the PF
+ * I40E_VFGEN_RSTAT on the VF
+ * When the PF initiates a reset, it writes 0
+ * When the reset is complete, it writes 1
+ * When the PF detects that the VF has recovered, it writes 2
+ * VF checks this register periodically to determine if a reset has occurred,
+ * then polls it to know when the reset is complete.
+ * If either the PF or VF reads the register while the hardware
+ * is in a reset state, it will return DEADBEEF, which, when masked
+ * will result in 3.
+ */
+enum i40e_vfr_states {
+	I40E_VFR_INPROGRESS = 0,
+	I40E_VFR_COMPLETED,
+	I40E_VFR_VFACTIVE,
+	I40E_VFR_UNKNOWN,
+};
+
+#endif /* _I40E_VIRTCHNL_H_ */