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   */
30  enum 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  
53  enum 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   */
71  struct 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  
82  struct 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  
89  typedef 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   */
119  struct 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   */
157  struct 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   */
178  struct cdx_mcdi_data {
179  	struct cdx_mcdi_iface iface;
180  	u32 fn_flags;
181  };
182  
cdx_mcdi_if(struct cdx_mcdi * cdx)183  static inline struct cdx_mcdi_iface *cdx_mcdi_if(struct cdx_mcdi *cdx)
184  {
185  	return cdx->mcdi ? &cdx->mcdi->iface : NULL;
186  }
187  
188  int cdx_mcdi_init(struct cdx_mcdi *cdx);
189  void cdx_mcdi_finish(struct cdx_mcdi *cdx);
190  
191  void cdx_mcdi_process_cmd(struct cdx_mcdi *cdx, struct cdx_dword *outbuf, int len);
192  int 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);
195  int 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);
199  int 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