1/* SPDX-License-Identifier: GPL-2.0-only */
2/****************************************************************************
3 * Driver for Solarflare network controllers and boards
4 * Copyright 2010-2012 Solarflare Communications Inc.
5 */
6#ifndef _VFDI_H
7#define _VFDI_H
8
9/**
10 * DOC: Virtual Function Driver Interface
11 *
12 * This file contains software structures used to form a two way
13 * communication channel between the VF driver and the PF driver,
14 * named Virtual Function Driver Interface (VFDI).
15 *
16 * For the purposes of VFDI, a page is a memory region with size and
17 * alignment of 4K.  All addresses are DMA addresses to be used within
18 * the domain of the relevant VF.
19 *
20 * The only hardware-defined channels for a VF driver to communicate
21 * with the PF driver are the event mailboxes (%FR_CZ_USR_EV
22 * registers).  Writing to these registers generates an event with
23 * EV_CODE = EV_CODE_USR_EV, USER_QID set to the index of the mailbox
24 * and USER_EV_REG_VALUE set to the value written.  The PF driver may
25 * direct or disable delivery of these events by setting
26 * %FR_CZ_USR_EV_CFG.
27 *
28 * The PF driver can send arbitrary events to arbitrary event queues.
29 * However, for consistency, VFDI events from the PF are defined to
30 * follow the same form and be sent to the first event queue assigned
31 * to the VF while that queue is enabled by the VF driver.
32 *
33 * The general form of the variable bits of VFDI events is:
34 *
35 *       0             16                       24   31
36 *      | DATA        | TYPE                   | SEQ   |
37 *
38 * SEQ is a sequence number which should be incremented by 1 (modulo
39 * 256) for each event.  The sequence numbers used in each direction
40 * are independent.
41 *
42 * The VF submits requests of type &struct vfdi_req by sending the
43 * address of the request (ADDR) in a series of 4 events:
44 *
45 *       0             16                       24   31
46 *      | ADDR[0:15]  | VFDI_EV_TYPE_REQ_WORD0 | SEQ   |
47 *      | ADDR[16:31] | VFDI_EV_TYPE_REQ_WORD1 | SEQ+1 |
48 *      | ADDR[32:47] | VFDI_EV_TYPE_REQ_WORD2 | SEQ+2 |
49 *      | ADDR[48:63] | VFDI_EV_TYPE_REQ_WORD3 | SEQ+3 |
50 *
51 * The address must be page-aligned.  After receiving such a valid
52 * series of events, the PF driver will attempt to read the request
53 * and write a response to the same address.  In case of an invalid
54 * sequence of events or a DMA error, there will be no response.
55 *
56 * The VF driver may request that the PF driver writes status
57 * information into its domain asynchronously.  After writing the
58 * status, the PF driver will send an event of the form:
59 *
60 *       0             16                       24   31
61 *      | reserved    | VFDI_EV_TYPE_STATUS    | SEQ   |
62 *
63 * In case the VF must be reset for any reason, the PF driver will
64 * send an event of the form:
65 *
66 *       0             16                       24   31
67 *      | reserved    | VFDI_EV_TYPE_RESET     | SEQ   |
68 *
69 * It is then the responsibility of the VF driver to request
70 * reinitialisation of its queues.
71 */
72#define VFDI_EV_SEQ_LBN 24
73#define VFDI_EV_SEQ_WIDTH 8
74#define VFDI_EV_TYPE_LBN 16
75#define VFDI_EV_TYPE_WIDTH 8
76#define VFDI_EV_TYPE_REQ_WORD0 0
77#define VFDI_EV_TYPE_REQ_WORD1 1
78#define VFDI_EV_TYPE_REQ_WORD2 2
79#define VFDI_EV_TYPE_REQ_WORD3 3
80#define VFDI_EV_TYPE_STATUS 4
81#define VFDI_EV_TYPE_RESET 5
82#define VFDI_EV_DATA_LBN 0
83#define VFDI_EV_DATA_WIDTH 16
84
85struct vfdi_endpoint {
86	u8 mac_addr[ETH_ALEN];
87	__be16 tci;
88};
89
90/**
91 * enum vfdi_op - VFDI operation enumeration
92 * @VFDI_OP_RESPONSE: Indicates a response to the request.
93 * @VFDI_OP_INIT_EVQ: Initialize SRAM entries and initialize an EVQ.
94 * @VFDI_OP_INIT_RXQ: Initialize SRAM entries and initialize an RXQ.
95 * @VFDI_OP_INIT_TXQ: Initialize SRAM entries and initialize a TXQ.
96 * @VFDI_OP_FINI_ALL_QUEUES: Flush all queues, finalize all queues, then
97 *	finalize the SRAM entries.
98 * @VFDI_OP_INSERT_FILTER: Insert a MAC filter targeting the given RXQ.
99 * @VFDI_OP_REMOVE_ALL_FILTERS: Remove all filters.
100 * @VFDI_OP_SET_STATUS_PAGE: Set the DMA page(s) used for status updates
101 *	from PF and write the initial status.
102 * @VFDI_OP_CLEAR_STATUS_PAGE: Clear the DMA page(s) used for status
103 *	updates from PF.
104 */
105enum vfdi_op {
106	VFDI_OP_RESPONSE = 0,
107	VFDI_OP_INIT_EVQ = 1,
108	VFDI_OP_INIT_RXQ = 2,
109	VFDI_OP_INIT_TXQ = 3,
110	VFDI_OP_FINI_ALL_QUEUES = 4,
111	VFDI_OP_INSERT_FILTER = 5,
112	VFDI_OP_REMOVE_ALL_FILTERS = 6,
113	VFDI_OP_SET_STATUS_PAGE = 7,
114	VFDI_OP_CLEAR_STATUS_PAGE = 8,
115	VFDI_OP_LIMIT,
116};
117
118/* Response codes for VFDI operations. Other values may be used in future. */
119#define VFDI_RC_SUCCESS		0
120#define VFDI_RC_ENOMEM		(-12)
121#define VFDI_RC_EINVAL		(-22)
122#define VFDI_RC_EOPNOTSUPP	(-95)
123#define VFDI_RC_ETIMEDOUT	(-110)
124
125/**
126 * struct vfdi_req - Request from VF driver to PF driver
127 * @op: Operation code or response indicator, taken from &enum vfdi_op.
128 * @rc: Response code.  Set to 0 on success or a negative error code on failure.
129 * @u.init_evq.index: Index of event queue to create.
130 * @u.init_evq.buf_count: Number of 4k buffers backing event queue.
131 * @u.init_evq.addr: Array of length %u.init_evq.buf_count containing DMA
132 *	address of each page backing the event queue.
133 * @u.init_rxq.index: Index of receive queue to create.
134 * @u.init_rxq.buf_count: Number of 4k buffers backing receive queue.
135 * @u.init_rxq.evq: Instance of event queue to target receive events at.
136 * @u.init_rxq.label: Label used in receive events.
137 * @u.init_rxq.flags: Unused.
138 * @u.init_rxq.addr: Array of length %u.init_rxq.buf_count containing DMA
139 *	address of each page backing the receive queue.
140 * @u.init_txq.index: Index of transmit queue to create.
141 * @u.init_txq.buf_count: Number of 4k buffers backing transmit queue.
142 * @u.init_txq.evq: Instance of event queue to target transmit completion
143 *	events at.
144 * @u.init_txq.label: Label used in transmit completion events.
145 * @u.init_txq.flags: Checksum offload flags.
146 * @u.init_txq.addr: Array of length %u.init_txq.buf_count containing DMA
147 *	address of each page backing the transmit queue.
148 * @u.mac_filter.rxq: Insert MAC filter at VF local address/VLAN targeting
149 *	all traffic at this receive queue.
150 * @u.mac_filter.flags: MAC filter flags.
151 * @u.set_status_page.dma_addr: Base address for the &struct vfdi_status.
152 *	This address must be page-aligned and the PF may write up to a
153 *	whole page (allowing for extension of the structure).
154 * @u.set_status_page.peer_page_count: Number of additional pages the VF
155 *	has provided into which peer addresses may be DMAd.
156 * @u.set_status_page.peer_page_addr: Array of DMA addresses of pages.
157 *	If the number of peers exceeds 256, then the VF must provide
158 *	additional pages in this array. The PF will then DMA up to
159 *	512 vfdi_endpoint structures into each page.  These addresses
160 *	must be page-aligned.
161 */
162struct vfdi_req {
163	u32 op;
164	u32 reserved1;
165	s32 rc;
166	u32 reserved2;
167	union {
168		struct {
169			u32 index;
170			u32 buf_count;
171			u64 addr[];
172		} init_evq;
173		struct {
174			u32 index;
175			u32 buf_count;
176			u32 evq;
177			u32 label;
178			u32 flags;
179#define VFDI_RXQ_FLAG_SCATTER_EN 1
180			u32 reserved;
181			u64 addr[];
182		} init_rxq;
183		struct {
184			u32 index;
185			u32 buf_count;
186			u32 evq;
187			u32 label;
188			u32 flags;
189#define VFDI_TXQ_FLAG_IP_CSUM_DIS 1
190#define VFDI_TXQ_FLAG_TCPUDP_CSUM_DIS 2
191			u32 reserved;
192			u64 addr[];
193		} init_txq;
194		struct {
195			u32 rxq;
196			u32 flags;
197#define VFDI_MAC_FILTER_FLAG_RSS 1
198#define VFDI_MAC_FILTER_FLAG_SCATTER 2
199		} mac_filter;
200		struct {
201			u64 dma_addr;
202			u64 peer_page_count;
203			u64 peer_page_addr[];
204		} set_status_page;
205	} u;
206};
207
208/**
209 * struct vfdi_status - Status provided by PF driver to VF driver
210 * @generation_start: A generation count DMA'd to VF *before* the
211 *	rest of the structure.
212 * @generation_end: A generation count DMA'd to VF *after* the
213 *	rest of the structure.
214 * @version: Version of this structure; currently set to 1.  Later
215 *	versions must either be layout-compatible or only be sent to VFs
216 *	that specifically request them.
217 * @length: Total length of this structure including embedded tables
218 * @vi_scale: log2 the number of VIs available on this VF. This quantity
219 *	is used by the hardware for register decoding.
220 * @max_tx_channels: The maximum number of transmit queues the VF can use.
221 * @rss_rxq_count: The number of receive queues present in the shared RSS
222 *	indirection table.
223 * @peer_count: Total number of peers in the complete peer list. If larger
224 *	than ARRAY_SIZE(%peers), then the VF must provide sufficient
225 *	additional pages each of which is filled with vfdi_endpoint structures.
226 * @local: The MAC address and outer VLAN tag of *this* VF
227 * @peers: Table of peer addresses.  The @tci fields in these structures
228 *	are currently unused and must be ignored.  Additional peers are
229 *	written into any additional pages provided by the VF.
230 * @timer_quantum_ns: Timer quantum (nominal period between timer ticks)
231 *	for interrupt moderation timers, in nanoseconds. This member is only
232 *	present if @length is sufficiently large.
233 */
234struct vfdi_status {
235	u32 generation_start;
236	u32 generation_end;
237	u32 version;
238	u32 length;
239	u8 vi_scale;
240	u8 max_tx_channels;
241	u8 rss_rxq_count;
242	u8 reserved1;
243	u16 peer_count;
244	u16 reserved2;
245	struct vfdi_endpoint local;
246	struct vfdi_endpoint peers[256];
247
248	/* Members below here extend version 1 of this structure */
249	u32 timer_quantum_ns;
250};
251
252#endif
253