xref: /openbmc/linux/drivers/net/ethernet/sfc/siena/vfdi.h (revision d48523cb)
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 
85 struct 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  */
105 enum 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  */
162 struct 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  */
234 struct 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