1/* SPDX-License-Identifier: GPL-2.0
2 *
3 * Copyright 2008-2013 Solarflare Communications Inc.
4 * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
5 */
6
7#ifndef CDX_MCDI_H
8#define CDX_MCDI_H
9
10#include <linux/mutex.h>
11#include <linux/kref.h>
12#include <linux/rpmsg.h>
13
14#include "bitfield.h"
15#include "mc_cdx_pcol.h"
16
17#ifdef DEBUG
18#define CDX_WARN_ON_ONCE_PARANOID(x) WARN_ON_ONCE(x)
19#define CDX_WARN_ON_PARANOID(x) WARN_ON(x)
20#else
21#define CDX_WARN_ON_ONCE_PARANOID(x) do {} while (0)
22#define CDX_WARN_ON_PARANOID(x) do {} while (0)
23#endif
24
25/**
26 * enum cdx_mcdi_mode - MCDI transaction mode
27 * @MCDI_MODE_EVENTS: wait for an mcdi response callback.
28 * @MCDI_MODE_FAIL: we think MCDI is dead, so fail-fast all calls
29 */
30enum cdx_mcdi_mode {
31	MCDI_MODE_EVENTS,
32	MCDI_MODE_FAIL,
33};
34
35#define MCDI_RPC_TIMEOUT	(10 * HZ)
36#define MCDI_RPC_LONG_TIMEOU	(60 * HZ)
37#define MCDI_RPC_POST_RST_TIME	(10 * HZ)
38
39#define MCDI_BUF_LEN (8 + MCDI_CTL_SDU_LEN_MAX)
40
41/**
42 * enum cdx_mcdi_cmd_state - State for an individual MCDI command
43 * @MCDI_STATE_QUEUED: Command not started and is waiting to run.
44 * @MCDI_STATE_RETRY: Command was submitted and MC rejected with no resources,
45 *	as MC have too many outstanding commands. Command will be retried once
46 *	another command returns.
47 * @MCDI_STATE_RUNNING: Command was accepted and is running.
48 * @MCDI_STATE_RUNNING_CANCELLED: Command is running but the issuer cancelled
49 *	the command.
50 * @MCDI_STATE_FINISHED: Processing of this command has completed.
51 */
52
53enum cdx_mcdi_cmd_state {
54	MCDI_STATE_QUEUED,
55	MCDI_STATE_RETRY,
56	MCDI_STATE_RUNNING,
57	MCDI_STATE_RUNNING_CANCELLED,
58	MCDI_STATE_FINISHED,
59};
60
61/**
62 * struct cdx_mcdi - CDX MCDI Firmware interface, to interact
63 *	with CDX controller.
64 * @mcdi: MCDI interface
65 * @mcdi_ops: MCDI operations
66 * @r5_rproc : R5 Remoteproc device handle
67 * @rpdev: RPMsg device
68 * @ept: RPMsg endpoint
69 * @work: Post probe work
70 */
71struct cdx_mcdi {
72	/* MCDI interface */
73	struct cdx_mcdi_data *mcdi;
74	const struct cdx_mcdi_ops *mcdi_ops;
75
76	struct rproc *r5_rproc;
77	struct rpmsg_device *rpdev;
78	struct rpmsg_endpoint *ept;
79	struct work_struct work;
80};
81
82struct cdx_mcdi_ops {
83	void (*mcdi_request)(struct cdx_mcdi *cdx,
84			     const struct cdx_dword *hdr, size_t hdr_len,
85			     const struct cdx_dword *sdu, size_t sdu_len);
86	unsigned int (*mcdi_rpc_timeout)(struct cdx_mcdi *cdx, unsigned int cmd);
87};
88
89typedef void cdx_mcdi_async_completer(struct cdx_mcdi *cdx,
90				      unsigned long cookie, int rc,
91				      struct cdx_dword *outbuf,
92				      size_t outlen_actual);
93
94/**
95 * struct cdx_mcdi_cmd - An outstanding MCDI command
96 * @ref: Reference count. There will be one reference if the command is
97 *	in the mcdi_iface cmd_list, another if it's on a cleanup list,
98 *	and a third if it's queued in the work queue.
99 * @list: The data for this entry in mcdi->cmd_list
100 * @cleanup_list: The data for this entry in a cleanup list
101 * @work: The work item for this command, queued in mcdi->workqueue
102 * @mcdi: The mcdi_iface for this command
103 * @state: The state of this command
104 * @inlen: inbuf length
105 * @inbuf: Input buffer
106 * @quiet: Whether to silence errors
107 * @reboot_seen: Whether a reboot has been seen during this command,
108 *	to prevent duplicates
109 * @seq: Sequence number
110 * @started: Jiffies this command was started at
111 * @cookie: Context for completion function
112 * @completer: Completion function
113 * @handle: Command handle
114 * @cmd: Command number
115 * @rc: Return code
116 * @outlen: Length of output buffer
117 * @outbuf: Output buffer
118 */
119struct cdx_mcdi_cmd {
120	struct kref ref;
121	struct list_head list;
122	struct list_head cleanup_list;
123	struct work_struct work;
124	struct cdx_mcdi_iface *mcdi;
125	enum cdx_mcdi_cmd_state state;
126	size_t inlen;
127	const struct cdx_dword *inbuf;
128	bool quiet;
129	bool reboot_seen;
130	u8 seq;
131	unsigned long started;
132	unsigned long cookie;
133	cdx_mcdi_async_completer *completer;
134	unsigned int handle;
135	unsigned int cmd;
136	int rc;
137	size_t outlen;
138	struct cdx_dword *outbuf;
139	/* followed by inbuf data if necessary */
140};
141
142/**
143 * struct cdx_mcdi_iface - MCDI protocol context
144 * @cdx: The associated NIC
145 * @iface_lock: Serialise access to this structure
146 * @outstanding_cleanups: Count of cleanups
147 * @cmd_list: List of outstanding and running commands
148 * @workqueue: Workqueue used for delayed processing
149 * @cmd_complete_wq: Waitqueue for command completion
150 * @db_held_by: Command the MC doorbell is in use by
151 * @seq_held_by: Command each sequence number is in use by
152 * @prev_handle: The last used command handle
153 * @mode: Poll for mcdi completion, or wait for an mcdi_event
154 * @prev_seq: The last used sequence number
155 * @new_epoch: Indicates start of day or start of MC reboot recovery
156 */
157struct cdx_mcdi_iface {
158	struct cdx_mcdi *cdx;
159	/* Serialise access */
160	struct mutex iface_lock;
161	unsigned int outstanding_cleanups;
162	struct list_head cmd_list;
163	struct workqueue_struct *workqueue;
164	wait_queue_head_t cmd_complete_wq;
165	struct cdx_mcdi_cmd *db_held_by;
166	struct cdx_mcdi_cmd *seq_held_by[16];
167	unsigned int prev_handle;
168	enum cdx_mcdi_mode mode;
169	u8 prev_seq;
170	bool new_epoch;
171};
172
173/**
174 * struct cdx_mcdi_data - extra state for NICs that implement MCDI
175 * @iface: Interface/protocol state
176 * @fn_flags: Flags for this function, as returned by %MC_CMD_DRV_ATTACH.
177 */
178struct cdx_mcdi_data {
179	struct cdx_mcdi_iface iface;
180	u32 fn_flags;
181};
182
183static inline struct cdx_mcdi_iface *cdx_mcdi_if(struct cdx_mcdi *cdx)
184{
185	return cdx->mcdi ? &cdx->mcdi->iface : NULL;
186}
187
188int cdx_mcdi_init(struct cdx_mcdi *cdx);
189void cdx_mcdi_finish(struct cdx_mcdi *cdx);
190
191void cdx_mcdi_process_cmd(struct cdx_mcdi *cdx, struct cdx_dword *outbuf, int len);
192int cdx_mcdi_rpc(struct cdx_mcdi *cdx, unsigned int cmd,
193		 const struct cdx_dword *inbuf, size_t inlen,
194		 struct cdx_dword *outbuf, size_t outlen, size_t *outlen_actual);
195int cdx_mcdi_rpc_async(struct cdx_mcdi *cdx, unsigned int cmd,
196		       const struct cdx_dword *inbuf, size_t inlen,
197		       cdx_mcdi_async_completer *complete,
198		       unsigned long cookie);
199int cdx_mcdi_wait_for_quiescence(struct cdx_mcdi *cdx,
200				 unsigned int timeout_jiffies);
201
202/*
203 * We expect that 16- and 32-bit fields in MCDI requests and responses
204 * are appropriately aligned, but 64-bit fields are only
205 * 32-bit-aligned.
206 */
207#define MCDI_DECLARE_BUF(_name, _len) struct cdx_dword _name[DIV_ROUND_UP(_len, 4)] = {{0}}
208#define _MCDI_PTR(_buf, _offset)					\
209	((u8 *)(_buf) + (_offset))
210#define MCDI_PTR(_buf, _field)						\
211	_MCDI_PTR(_buf, MC_CMD_ ## _field ## _OFST)
212#define _MCDI_CHECK_ALIGN(_ofst, _align)				\
213	((void)BUILD_BUG_ON_ZERO((_ofst) & ((_align) - 1)),		\
214	 (_ofst))
215#define _MCDI_DWORD(_buf, _field)					\
216	((_buf) + (_MCDI_CHECK_ALIGN(MC_CMD_ ## _field ## _OFST, 4) >> 2))
217
218#define MCDI_BYTE(_buf, _field)						\
219	((void)BUILD_BUG_ON_ZERO(MC_CMD_ ## _field ## _LEN != 1),	\
220	 *MCDI_PTR(_buf, _field))
221#define MCDI_WORD(_buf, _field)						\
222	((void)BUILD_BUG_ON_ZERO(MC_CMD_ ## _field ## _LEN != 2),	\
223	 le16_to_cpu(*(__force const __le16 *)MCDI_PTR(_buf, _field)))
224#define MCDI_SET_DWORD(_buf, _field, _value)				\
225	CDX_POPULATE_DWORD_1(*_MCDI_DWORD(_buf, _field), CDX_DWORD, _value)
226#define MCDI_DWORD(_buf, _field)					\
227	CDX_DWORD_FIELD(*_MCDI_DWORD(_buf, _field), CDX_DWORD)
228#define MCDI_POPULATE_DWORD_1(_buf, _field, _name1, _value1)		\
229	CDX_POPULATE_DWORD_1(*_MCDI_DWORD(_buf, _field),		\
230			     MC_CMD_ ## _name1, _value1)
231#define MCDI_SET_QWORD(_buf, _field, _value)				\
232	do {								\
233		CDX_POPULATE_DWORD_1(_MCDI_DWORD(_buf, _field)[0],	\
234				     CDX_DWORD, (u32)(_value));	\
235		CDX_POPULATE_DWORD_1(_MCDI_DWORD(_buf, _field)[1],	\
236				     CDX_DWORD, (u64)(_value) >> 32);	\
237	} while (0)
238#define MCDI_QWORD(_buf, _field)					\
239	(CDX_DWORD_FIELD(_MCDI_DWORD(_buf, _field)[0], CDX_DWORD) |	\
240	(u64)CDX_DWORD_FIELD(_MCDI_DWORD(_buf, _field)[1], CDX_DWORD) << 32)
241
242#endif /* CDX_MCDI_H */
243