1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2011-2017, The Linux Foundation
4  */
5 
6 #ifndef _DRIVERS_SLIMBUS_H
7 #define _DRIVERS_SLIMBUS_H
8 #include <linux/module.h>
9 #include <linux/device.h>
10 #include <linux/mutex.h>
11 #include <linux/completion.h>
12 #include <linux/slimbus.h>
13 
14 /* Standard values per SLIMbus spec needed by controllers and devices */
15 #define SLIM_CL_PER_SUPERFRAME		6144
16 #define SLIM_CL_PER_SUPERFRAME_DIV8	(SLIM_CL_PER_SUPERFRAME >> 3)
17 
18 /* SLIMbus message types. Related to interpretation of message code. */
19 #define SLIM_MSG_MT_CORE			0x0
20 #define SLIM_MSG_MT_DEST_REFERRED_USER		0x2
21 #define SLIM_MSG_MT_SRC_REFERRED_USER		0x6
22 
23 /*
24  * SLIM Broadcast header format
25  * BYTE 0: MT[7:5] RL[4:0]
26  * BYTE 1: RSVD[7] MC[6:0]
27  * BYTE 2: RSVD[7:6] DT[5:4] PI[3:0]
28  */
29 #define SLIM_MSG_MT_MASK	GENMASK(2, 0)
30 #define SLIM_MSG_MT_SHIFT	5
31 #define SLIM_MSG_RL_MASK	GENMASK(4, 0)
32 #define SLIM_MSG_RL_SHIFT	0
33 #define SLIM_MSG_MC_MASK	GENMASK(6, 0)
34 #define SLIM_MSG_MC_SHIFT	0
35 #define SLIM_MSG_DT_MASK	GENMASK(1, 0)
36 #define SLIM_MSG_DT_SHIFT	4
37 
38 #define SLIM_HEADER_GET_MT(b)	((b >> SLIM_MSG_MT_SHIFT) & SLIM_MSG_MT_MASK)
39 #define SLIM_HEADER_GET_RL(b)	((b >> SLIM_MSG_RL_SHIFT) & SLIM_MSG_RL_MASK)
40 #define SLIM_HEADER_GET_MC(b)	((b >> SLIM_MSG_MC_SHIFT) & SLIM_MSG_MC_MASK)
41 #define SLIM_HEADER_GET_DT(b)	((b >> SLIM_MSG_DT_SHIFT) & SLIM_MSG_DT_MASK)
42 
43 /* Device management messages used by this framework */
44 #define SLIM_MSG_MC_REPORT_PRESENT               0x1
45 #define SLIM_MSG_MC_ASSIGN_LOGICAL_ADDRESS       0x2
46 #define SLIM_MSG_MC_REPORT_ABSENT                0xF
47 
48 /* Data channel management messages */
49 #define SLIM_MSG_MC_CONNECT_SOURCE		0x10
50 #define SLIM_MSG_MC_CONNECT_SINK		0x11
51 #define SLIM_MSG_MC_DISCONNECT_PORT		0x14
52 #define SLIM_MSG_MC_CHANGE_CONTENT		0x18
53 
54 /* Clock pause Reconfiguration messages */
55 #define SLIM_MSG_MC_BEGIN_RECONFIGURATION        0x40
56 #define SLIM_MSG_MC_NEXT_PAUSE_CLOCK             0x4A
57 #define SLIM_MSG_MC_NEXT_DEFINE_CHANNEL          0x50
58 #define SLIM_MSG_MC_NEXT_DEFINE_CONTENT          0x51
59 #define SLIM_MSG_MC_NEXT_ACTIVATE_CHANNEL        0x54
60 #define SLIM_MSG_MC_NEXT_DEACTIVATE_CHANNEL      0x55
61 #define SLIM_MSG_MC_NEXT_REMOVE_CHANNEL          0x58
62 #define SLIM_MSG_MC_RECONFIGURE_NOW              0x5F
63 
64 /*
65  * Clock pause flag to indicate that the reconfig message
66  * corresponds to clock pause sequence
67  */
68 #define SLIM_MSG_CLK_PAUSE_SEQ_FLG		(1U << 8)
69 
70 /* Clock pause values per SLIMbus spec */
71 #define SLIM_CLK_FAST				0
72 #define SLIM_CLK_CONST_PHASE			1
73 #define SLIM_CLK_UNSPECIFIED			2
74 
75 /* Destination type Values */
76 #define SLIM_MSG_DEST_LOGICALADDR	0
77 #define SLIM_MSG_DEST_ENUMADDR		1
78 #define	SLIM_MSG_DEST_BROADCAST		3
79 
80 /* Standard values per SLIMbus spec needed by controllers and devices */
81 #define SLIM_MAX_CLK_GEAR		10
82 #define SLIM_MIN_CLK_GEAR		1
83 #define SLIM_SLOT_LEN_BITS		4
84 
85 /* Indicate that the frequency of the flow and the bus frequency are locked */
86 #define SLIM_CHANNEL_CONTENT_FL		BIT(7)
87 
88 /* Standard values per SLIMbus spec needed by controllers and devices */
89 #define SLIM_CL_PER_SUPERFRAME		6144
90 #define SLIM_SLOTS_PER_SUPERFRAME	(SLIM_CL_PER_SUPERFRAME >> 2)
91 #define SLIM_SL_PER_SUPERFRAME		(SLIM_CL_PER_SUPERFRAME >> 2)
92 /* Manager's logical address is set to 0xFF per spec */
93 #define SLIM_LA_MANAGER 0xFF
94 
95 #define SLIM_MAX_TIDS			256
96 /**
97  * struct slim_framer - Represents SLIMbus framer.
98  * Every controller may have multiple framers. There is 1 active framer device
99  * responsible for clocking the bus.
100  * Manager is responsible for framer hand-over.
101  * @dev: Driver model representation of the device.
102  * @e_addr: Enumeration address of the framer.
103  * @rootfreq: Root Frequency at which the framer can run. This is maximum
104  *	frequency ('clock gear 10') at which the bus can operate.
105  * @superfreq: Superframes per root frequency. Every frame is 6144 bits.
106  */
107 struct slim_framer {
108 	struct device		dev;
109 	struct slim_eaddr	e_addr;
110 	int			rootfreq;
111 	int			superfreq;
112 };
113 
114 #define to_slim_framer(d) container_of(d, struct slim_framer, dev)
115 
116 /**
117  * struct slim_msg_txn - Message to be sent by the controller.
118  *			This structure has packet header,
119  *			payload and buffer to be filled (if any)
120  * @rl: Header field. remaining length.
121  * @mt: Header field. Message type.
122  * @mc: Header field. LSB is message code for type mt.
123  * @dt: Header field. Destination type.
124  * @ec: Element code. Used for elemental access APIs.
125  * @tid: Transaction ID. Used for messages expecting response.
126  *	(relevant for message-codes involving read operation)
127  * @la: Logical address of the device this message is going to.
128  *	(Not used when destination type is broadcast.)
129  * @msg: Elemental access message to be read/written
130  * @comp: completion if read/write is synchronous, used internally
131  *	for tid based transactions.
132  */
133 struct slim_msg_txn {
134 	u8			rl;
135 	u8			mt;
136 	u8			mc;
137 	u8			dt;
138 	u16			ec;
139 	u8			tid;
140 	u8			la;
141 	struct slim_val_inf	*msg;
142 	struct	completion	*comp;
143 };
144 
145 /* Frequently used message transaction structures */
146 #define DEFINE_SLIM_LDEST_TXN(name, mc, rl, la, msg) \
147 	struct slim_msg_txn name = { rl, 0, mc, SLIM_MSG_DEST_LOGICALADDR, 0,\
148 					0, la, msg, }
149 
150 #define DEFINE_SLIM_BCAST_TXN(name, mc, rl, la, msg) \
151 	struct slim_msg_txn name = { rl, 0, mc, SLIM_MSG_DEST_BROADCAST, 0,\
152 					0, la, msg, }
153 
154 #define DEFINE_SLIM_EDEST_TXN(name, mc, rl, la, msg) \
155 	struct slim_msg_txn name = { rl, 0, mc, SLIM_MSG_DEST_ENUMADDR, 0,\
156 					0, la, msg, }
157 /**
158  * enum slim_clk_state: SLIMbus controller's clock state used internally for
159  *	maintaining current clock state.
160  * @SLIM_CLK_ACTIVE: SLIMbus clock is active
161  * @SLIM_CLK_ENTERING_PAUSE: SLIMbus clock pause sequence is being sent on the
162  *	bus. If this succeeds, state changes to SLIM_CLK_PAUSED. If the
163  *	transition fails, state changes back to SLIM_CLK_ACTIVE
164  * @SLIM_CLK_PAUSED: SLIMbus controller clock has paused.
165  */
166 enum slim_clk_state {
167 	SLIM_CLK_ACTIVE,
168 	SLIM_CLK_ENTERING_PAUSE,
169 	SLIM_CLK_PAUSED,
170 };
171 
172 /**
173  * struct slim_sched: Framework uses this structure internally for scheduling.
174  * @clk_state: Controller's clock state from enum slim_clk_state
175  * @pause_comp: Signals completion of clock pause sequence. This is useful when
176  *	client tries to call SLIMbus transaction when controller is entering
177  *	clock pause.
178  * @m_reconf: This mutex is held until current reconfiguration (data channel
179  *	scheduling, message bandwidth reservation) is done. Message APIs can
180  *	use the bus concurrently when this mutex is held since elemental access
181  *	messages can be sent on the bus when reconfiguration is in progress.
182  */
183 struct slim_sched {
184 	enum slim_clk_state	clk_state;
185 	struct completion	pause_comp;
186 	struct mutex		m_reconf;
187 };
188 
189 /**
190  * enum slim_port_direction: SLIMbus port direction
191  *
192  * @SLIM_PORT_SINK: SLIMbus port is a sink
193  * @SLIM_PORT_SOURCE: SLIMbus port is a source
194  */
195 enum slim_port_direction {
196 	SLIM_PORT_SINK = 0,
197 	SLIM_PORT_SOURCE,
198 };
199 /**
200  * enum slim_port_state: SLIMbus Port/Endpoint state machine
201  *	according to SLIMbus Spec 2.0
202  * @SLIM_PORT_DISCONNECTED: SLIMbus port is disconnected
203  *	entered from Unconfigure/configured state after
204  *	DISCONNECT_PORT or REMOVE_CHANNEL core command
205  * @SLIM_PORT_UNCONFIGURED: SLIMbus port is in unconfigured state.
206  *	entered from disconnect state after CONNECT_SOURCE/SINK core command
207  * @SLIM_PORT_CONFIGURED: SLIMbus port is in configured state.
208  *	entered from unconfigured state after DEFINE_CHANNEL, DEFINE_CONTENT
209  *	and ACTIVATE_CHANNEL core commands. Ready for data transmission.
210  */
211 enum slim_port_state {
212 	SLIM_PORT_DISCONNECTED = 0,
213 	SLIM_PORT_UNCONFIGURED,
214 	SLIM_PORT_CONFIGURED,
215 };
216 
217 /**
218  * enum slim_channel_state: SLIMbus channel state machine used by core.
219  * @SLIM_CH_STATE_DISCONNECTED: SLIMbus channel is disconnected
220  * @SLIM_CH_STATE_ALLOCATED: SLIMbus channel is allocated
221  * @SLIM_CH_STATE_ASSOCIATED: SLIMbus channel is associated with port
222  * @SLIM_CH_STATE_DEFINED: SLIMbus channel parameters are defined
223  * @SLIM_CH_STATE_CONTENT_DEFINED: SLIMbus channel content is defined
224  * @SLIM_CH_STATE_ACTIVE: SLIMbus channel is active and ready for data
225  * @SLIM_CH_STATE_REMOVED: SLIMbus channel is inactive and removed
226  */
227 enum slim_channel_state {
228 	SLIM_CH_STATE_DISCONNECTED = 0,
229 	SLIM_CH_STATE_ALLOCATED,
230 	SLIM_CH_STATE_ASSOCIATED,
231 	SLIM_CH_STATE_DEFINED,
232 	SLIM_CH_STATE_CONTENT_DEFINED,
233 	SLIM_CH_STATE_ACTIVE,
234 	SLIM_CH_STATE_REMOVED,
235 };
236 
237 /**
238  * enum slim_ch_data_fmt: SLIMbus channel data Type identifiers according to
239  *	Table 60 of SLIMbus Spec 1.01.01
240  * @SLIM_CH_DATA_FMT_NOT_DEFINED: Undefined
241  * @SLIM_CH_DATA_FMT_LPCM_AUDIO: LPCM audio
242  * @SLIM_CH_DATA_FMT_IEC61937_COMP_AUDIO: IEC61937 Compressed audio
243  * @SLIM_CH_DATA_FMT_PACKED_PDM_AUDIO: Packed PDM audio
244  */
245 enum slim_ch_data_fmt {
246 	SLIM_CH_DATA_FMT_NOT_DEFINED = 0,
247 	SLIM_CH_DATA_FMT_LPCM_AUDIO = 1,
248 	SLIM_CH_DATA_FMT_IEC61937_COMP_AUDIO = 2,
249 	SLIM_CH_DATA_FMT_PACKED_PDM_AUDIO = 3,
250 };
251 
252 /**
253  * enum slim_ch_aux_fmt: SLIMbus channel Aux Field format IDs according to
254  *	Table 63 of SLIMbus Spec 2.0
255  * @SLIM_CH_AUX_FMT_NOT_APPLICABLE: Undefined
256  * @SLIM_CH_AUX_FMT_ZCUV_TUNNEL_IEC60958: ZCUV for tunneling IEC60958
257  * @SLIM_CH_AUX_FMT_USER_DEFINED: User defined
258  */
259 enum slim_ch_aux_bit_fmt {
260 	SLIM_CH_AUX_FMT_NOT_APPLICABLE = 0,
261 	SLIM_CH_AUX_FMT_ZCUV_TUNNEL_IEC60958 = 1,
262 	SLIM_CH_AUX_FMT_USER_DEFINED = 0xF,
263 };
264 
265 /**
266  * struct slim_channel  - SLIMbus channel, used for state machine
267  *
268  * @id: ID of channel
269  * @prrate: Presense rate of channel from Table 66 of SLIMbus 2.0 Specs
270  * @seg_dist: segment distribution code from Table 20 of SLIMbus 2.0 Specs
271  * @data_fmt: Data format of channel.
272  * @aux_fmt: Aux format for this channel.
273  * @state: channel state machine
274  */
275 struct slim_channel {
276 	int id;
277 	int prrate;
278 	int seg_dist;
279 	enum slim_ch_data_fmt data_fmt;
280 	enum slim_ch_aux_bit_fmt aux_fmt;
281 	enum slim_channel_state state;
282 };
283 
284 /**
285  * struct slim_port  - SLIMbus port
286  *
287  * @id: Port id
288  * @direction: Port direction, Source or Sink.
289  * @state: state machine of port.
290  * @ch: channel associated with this port.
291  */
292 struct slim_port {
293 	int id;
294 	enum slim_port_direction direction;
295 	enum slim_port_state state;
296 	struct slim_channel ch;
297 };
298 
299 /**
300  * enum slim_transport_protocol: SLIMbus Transport protocol list from
301  *	Table 47 of SLIMbus 2.0 specs.
302  * @SLIM_PROTO_ISO: Isochronous Protocol, no flow control as data rate match
303  *		channel rate flow control embedded in the data.
304  * @SLIM_PROTO_PUSH: Pushed Protocol, includes flow control, Used to carry
305  *		data whose rate	is equal to, or lower than the channel rate.
306  * @SLIM_PROTO_PULL: Pulled Protocol, similar usage as pushed protocol
307  *		but pull is a unicast.
308  * @SLIM_PROTO_LOCKED: Locked Protocol
309  * @SLIM_PROTO_ASYNC_SMPLX: Asynchronous Protocol-Simplex
310  * @SLIM_PROTO_ASYNC_HALF_DUP: Asynchronous Protocol-Half-duplex
311  * @SLIM_PROTO_EXT_SMPLX: Extended Asynchronous Protocol-Simplex
312  * @SLIM_PROTO_EXT_HALF_DUP: Extended Asynchronous Protocol-Half-duplex
313  */
314 enum slim_transport_protocol {
315 	SLIM_PROTO_ISO = 0,
316 	SLIM_PROTO_PUSH,
317 	SLIM_PROTO_PULL,
318 	SLIM_PROTO_LOCKED,
319 	SLIM_PROTO_ASYNC_SMPLX,
320 	SLIM_PROTO_ASYNC_HALF_DUP,
321 	SLIM_PROTO_EXT_SMPLX,
322 	SLIM_PROTO_EXT_HALF_DUP,
323 };
324 
325 /**
326  * struct slim_stream_runtime  - SLIMbus stream runtime instance
327  *
328  * @name: Name of the stream
329  * @dev: SLIM Device instance associated with this stream
330  * @direction: direction of stream
331  * @prot: Transport protocol used in this stream
332  * @rate: Data rate of samples *
333  * @bps: bits per sample
334  * @ratem: rate multipler which is super frame rate/data rate
335  * @num_ports: number of ports
336  * @ports: pointer to instance of ports
337  * @node: list head for stream associated with slim device.
338  */
339 struct slim_stream_runtime {
340 	const char *name;
341 	struct slim_device *dev;
342 	int direction;
343 	enum slim_transport_protocol prot;
344 	unsigned int rate;
345 	unsigned int bps;
346 	unsigned int ratem;
347 	int num_ports;
348 	struct slim_port *ports;
349 	struct list_head node;
350 };
351 
352 /**
353  * struct slim_controller  - Controls every instance of SLIMbus
354  *				(similar to 'master' on SPI)
355  * @dev: Device interface to this driver
356  * @id: Board-specific number identifier for this controller/bus
357  * @name: Name for this controller
358  * @min_cg: Minimum clock gear supported by this controller (default value: 1)
359  * @max_cg: Maximum clock gear supported by this controller (default value: 10)
360  * @clkgear: Current clock gear in which this bus is running
361  * @laddr_ida: logical address id allocator
362  * @a_framer: Active framer which is clocking the bus managed by this controller
363  * @lock: Mutex protecting controller data structures
364  * @devices: Slim device list
365  * @tid_idr: tid id allocator
366  * @txn_lock: Lock to protect table of transactions
367  * @sched: scheduler structure used by the controller
368  * @xfer_msg: Transfer a message on this controller (this can be a broadcast
369  *	control/status message like data channel setup, or a unicast message
370  *	like value element read/write.
371  * @set_laddr: Setup logical address at laddr for the slave with elemental
372  *	address e_addr. Drivers implementing controller will be expected to
373  *	send unicast message to this device with its logical address.
374  * @get_laddr: It is possible that controller needs to set fixed logical
375  *	address table and get_laddr can be used in that case so that controller
376  *	can do this assignment. Use case is when the master is on the remote
377  *	processor side, who is resposible for allocating laddr.
378  * @wakeup: This function pointer implements controller-specific procedure
379  *	to wake it up from clock-pause. Framework will call this to bring
380  *	the controller out of clock pause.
381  * @enable_stream: This function pointer implements controller-specific procedure
382  *	to enable a stream.
383  * @disable_stream: This function pointer implements controller-specific procedure
384  *	to disable stream.
385  *
386  *	'Manager device' is responsible for  device management, bandwidth
387  *	allocation, channel setup, and port associations per channel.
388  *	Device management means Logical address assignment/removal based on
389  *	enumeration (report-present, report-absent) of a device.
390  *	Bandwidth allocation is done dynamically by the manager based on active
391  *	channels on the bus, message-bandwidth requests made by SLIMbus devices.
392  *	Based on current bandwidth usage, manager chooses a frequency to run
393  *	the bus at (in steps of 'clock-gear', 1 through 10, each clock gear
394  *	representing twice the frequency than the previous gear).
395  *	Manager is also responsible for entering (and exiting) low-power-mode
396  *	(known as 'clock pause').
397  *	Manager can do handover of framer if there are multiple framers on the
398  *	bus and a certain usecase warrants using certain framer to avoid keeping
399  *	previous framer being powered-on.
400  *
401  *	Controller here performs duties of the manager device, and 'interface
402  *	device'. Interface device is responsible for monitoring the bus and
403  *	reporting information such as loss-of-synchronization, data
404  *	slot-collision.
405  */
406 struct slim_controller {
407 	struct device		*dev;
408 	unsigned int		id;
409 	char			name[SLIMBUS_NAME_SIZE];
410 	int			min_cg;
411 	int			max_cg;
412 	int			clkgear;
413 	struct ida		laddr_ida;
414 	struct slim_framer	*a_framer;
415 	struct mutex		lock;
416 	struct list_head	devices;
417 	struct idr		tid_idr;
418 	spinlock_t		txn_lock;
419 	struct slim_sched	sched;
420 	int			(*xfer_msg)(struct slim_controller *ctrl,
421 					    struct slim_msg_txn *tx);
422 	int			(*set_laddr)(struct slim_controller *ctrl,
423 					     struct slim_eaddr *ea, u8 laddr);
424 	int			(*get_laddr)(struct slim_controller *ctrl,
425 					     struct slim_eaddr *ea, u8 *laddr);
426 	int		(*enable_stream)(struct slim_stream_runtime *rt);
427 	int		(*disable_stream)(struct slim_stream_runtime *rt);
428 	int			(*wakeup)(struct slim_controller *ctrl);
429 };
430 
431 int slim_device_report_present(struct slim_controller *ctrl,
432 			       struct slim_eaddr *e_addr, u8 *laddr);
433 void slim_report_absent(struct slim_device *sbdev);
434 int slim_register_controller(struct slim_controller *ctrl);
435 int slim_unregister_controller(struct slim_controller *ctrl);
436 void slim_msg_response(struct slim_controller *ctrl, u8 *reply, u8 tid, u8 l);
437 int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn);
438 int slim_ctrl_clk_pause(struct slim_controller *ctrl, bool wakeup, u8 restart);
439 int slim_alloc_txn_tid(struct slim_controller *ctrl, struct slim_msg_txn *txn);
440 void slim_free_txn_tid(struct slim_controller *ctrl, struct slim_msg_txn *txn);
441 
slim_tid_txn(u8 mt,u8 mc)442 static inline bool slim_tid_txn(u8 mt, u8 mc)
443 {
444 	return (mt == SLIM_MSG_MT_CORE &&
445 		(mc == SLIM_MSG_MC_REQUEST_INFORMATION ||
446 		 mc == SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION ||
447 		 mc == SLIM_MSG_MC_REQUEST_VALUE ||
448 		 mc == SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION));
449 }
450 
slim_ec_txn(u8 mt,u8 mc)451 static inline bool slim_ec_txn(u8 mt, u8 mc)
452 {
453 	return (mt == SLIM_MSG_MT_CORE &&
454 		((mc >= SLIM_MSG_MC_REQUEST_INFORMATION &&
455 		  mc <= SLIM_MSG_MC_REPORT_INFORMATION) ||
456 		 (mc >= SLIM_MSG_MC_REQUEST_VALUE &&
457 		  mc <= SLIM_MSG_MC_CHANGE_VALUE)));
458 }
459 #endif /* _LINUX_SLIMBUS_H */
460