1 #ifndef _FIREWIRE_FWSERIAL_H
2 #define _FIREWIRE_FWSERIAL_H
3
4 #include <linux/kernel.h>
5 #include <linux/tty.h>
6 #include <linux/tty_driver.h>
7 #include <linux/tty_flip.h>
8 #include <linux/list.h>
9 #include <linux/firewire.h>
10 #include <linux/firewire-constants.h>
11 #include <linux/spinlock.h>
12 #include <linux/rcupdate.h>
13 #include <linux/mutex.h>
14 #include <linux/serial.h>
15 #include <linux/serial_reg.h>
16 #include <linux/module.h>
17 #include <linux/seq_file.h>
18 #include <linux/debugfs.h>
19
20 #include "dma_fifo.h"
21
22 #ifdef FWTTY_PROFILING
23 #define DISTRIBUTION_MAX_SIZE 8192
24 #define DISTRIBUTION_MAX_INDEX (ilog2(DISTRIBUTION_MAX_SIZE) + 1)
fwtty_profile_data(unsigned stat[],unsigned val)25 static inline void fwtty_profile_data(unsigned stat[], unsigned val)
26 {
27 int n = (val) ? min(ilog2(val) + 1, DISTRIBUTION_MAX_INDEX) : 0;
28 ++stat[n];
29 }
30 #else
31 #define DISTRIBUTION_MAX_INDEX 0
32 #define fwtty_profile_data(st, n)
33 #endif
34
35 /* Parameters for both VIRT_CABLE_PLUG & VIRT_CABLE_PLUG_RSP mgmt codes */
36 struct virt_plug_params {
37 __be32 status_hi;
38 __be32 status_lo;
39 __be32 fifo_hi;
40 __be32 fifo_lo;
41 __be32 fifo_len;
42 };
43
44 struct peer_work_params {
45 union {
46 struct virt_plug_params plug_req;
47 };
48 };
49
50 /**
51 * fwtty_peer: structure representing local & remote unit devices
52 * @unit: unit child device of fw_device node
53 * @serial: back pointer to associated fw_serial aggregate
54 * @guid: unique 64-bit guid for this unit device
55 * @generation: most recent bus generation
56 * @node_id: most recent node_id
57 * @speed: link speed of peer (0 = S100, 2 = S400, ... 5 = S3200)
58 * @mgmt_addr: bus addr region to write mgmt packets to
59 * @status_addr: bus addr register to write line status to
60 * @fifo_addr: bus addr region to write serial output to
61 * @fifo_len: max length for single write to fifo_addr
62 * @list: link for insertion into fw_serial's peer_list
63 * @rcu: for deferring peer reclamation
64 * @lock: spinlock to synchonize changes to state & port fields
65 * @work: only one work item can be queued at any one time
66 * Note: pending work is canceled prior to removal, so this
67 * peer is valid for at least the lifetime of the work function
68 * @work_params: parameter block for work functions
69 * @timer: timer for resetting peer state if remote request times out
70 * @state: current state
71 * @connect: work item for auto-connecting
72 * @connect_retries: # of connections already attempted
73 * @port: associated tty_port (usable if state == FWSC_ATTACHED)
74 */
75 struct fwtty_peer {
76 struct fw_unit *unit;
77 struct fw_serial *serial;
78 u64 guid;
79 int generation;
80 int node_id;
81 unsigned speed;
82 int max_payload;
83 u64 mgmt_addr;
84
85 /* these are usable only if state == FWSC_ATTACHED */
86 u64 status_addr;
87 u64 fifo_addr;
88 int fifo_len;
89
90 struct list_head list;
91 struct rcu_head rcu;
92
93 spinlock_t lock;
94 work_func_t workfn;
95 struct work_struct work;
96 struct peer_work_params work_params;
97 struct timer_list timer;
98 int state;
99 struct delayed_work connect;
100 int connect_retries;
101
102 struct fwtty_port *port;
103 };
104
105 #define to_peer(ptr, field) (container_of(ptr, struct fwtty_peer, field))
106
107 /* state values for fwtty_peer.state field */
108 enum fwtty_peer_state {
109 FWPS_GONE,
110 FWPS_NOT_ATTACHED,
111 FWPS_ATTACHED,
112 FWPS_PLUG_PENDING,
113 FWPS_PLUG_RESPONDING,
114 FWPS_UNPLUG_PENDING,
115 FWPS_UNPLUG_RESPONDING,
116
117 FWPS_NO_MGMT_ADDR = -1,
118 };
119
120 #define CONNECT_RETRY_DELAY HZ
121 #define MAX_CONNECT_RETRIES 10
122
123 /* must be holding peer lock for these state funclets */
peer_set_state(struct fwtty_peer * peer,int new)124 static inline void peer_set_state(struct fwtty_peer *peer, int new)
125 {
126 peer->state = new;
127 }
128
peer_revert_state(struct fwtty_peer * peer)129 static inline struct fwtty_port *peer_revert_state(struct fwtty_peer *peer)
130 {
131 struct fwtty_port *port = peer->port;
132
133 peer->port = NULL;
134 peer_set_state(peer, FWPS_NOT_ATTACHED);
135 return port;
136 }
137
138 struct fwserial_mgmt_pkt {
139 struct {
140 __be16 len;
141 __be16 code;
142 } hdr;
143 union {
144 struct virt_plug_params plug_req;
145 struct virt_plug_params plug_rsp;
146 };
147 } __packed;
148
149 /* fwserial_mgmt_packet codes */
150 #define FWSC_RSP_OK 0x0000
151 #define FWSC_RSP_NACK 0x8000
152 #define FWSC_CODE_MASK 0x0fff
153
154 #define FWSC_VIRT_CABLE_PLUG 1
155 #define FWSC_VIRT_CABLE_UNPLUG 2
156 #define FWSC_VIRT_CABLE_PLUG_RSP 3
157 #define FWSC_VIRT_CABLE_UNPLUG_RSP 4
158
159 /* 1 min. plug timeout -- suitable for userland authorization */
160 #define VIRT_CABLE_PLUG_TIMEOUT (60 * HZ)
161
162 struct stats {
163 unsigned xchars;
164 unsigned dropped;
165 unsigned tx_stall;
166 unsigned fifo_errs;
167 unsigned sent;
168 unsigned lost;
169 unsigned throttled;
170 unsigned reads[DISTRIBUTION_MAX_INDEX + 1];
171 unsigned writes[DISTRIBUTION_MAX_INDEX + 1];
172 unsigned txns[DISTRIBUTION_MAX_INDEX + 1];
173 unsigned unthrottle[DISTRIBUTION_MAX_INDEX + 1];
174 };
175
176 struct fwconsole_ops {
177 void (*notify)(int code, void *data);
178 void (*stats)(struct stats *stats, void *data);
179 void (*proc_show)(struct seq_file *m, void *data);
180 };
181
182 /* codes for console ops notify */
183 #define FWCON_NOTIFY_ATTACH 1
184 #define FWCON_NOTIFY_DETACH 2
185
186 /**
187 * fwtty_port: structure used to track/represent underlying tty_port
188 * @port: underlying tty_port
189 * @device: tty device
190 * @index: index into port_table for this particular port
191 * note: minor = index + minor_start assigned by tty_alloc_driver()
192 * @serial: back pointer to the containing fw_serial
193 * @rx_handler: bus address handler for unique addr region used by remotes
194 * to communicate with this port. Every port uses
195 * fwtty_port_handler() for per port transactions.
196 * @fwcon_ops: ops for attached fw_console (if any)
197 * @con_data: private data for fw_console
198 * @wait_tx: waitqueue for sleeping until writer/drain completes tx
199 * @emit_breaks: delayed work responsible for generating breaks when the
200 * break line status is active
201 * @cps : characters per second computed from the termios settings
202 * @break_last: timestamp in jiffies from last emit_breaks
203 * @hangup: work responsible for HUPing when carrier is dropped/lost
204 * @mstatus: loose virtualization of LSR/MSR
205 * bits 15..0 correspond to TIOCM_* bits
206 * bits 19..16 reserved for mctrl
207 * bit 20 OOB_TX_THROTTLE
208 * bits 23..21 reserved
209 * bits 31..24 correspond to UART_LSR_* bits
210 * @lock: spinlock for protecting concurrent access to fields below it
211 * @mctrl: loose virtualization of MCR
212 * bits 15..0 correspond to TIOCM_* bits
213 * bit 16 OOB_RX_THROTTLE
214 * bits 19..17 reserved
215 * bits 31..20 reserved for mstatus
216 * @drain: delayed work scheduled to ensure that writes are flushed.
217 * The work can race with the writer but concurrent sending is
218 * prevented with the IN_TX flag. Scheduled under lock to
219 * limit scheduling when fifo has just been drained.
220 * @tx_fifo: fifo used to store & block-up writes for dma to remote
221 * @max_payload: max bytes transmissible per dma (based on peer's max_payload)
222 * @status_mask: UART_LSR_* bitmask significant to rx (based on termios)
223 * @ignore_mask: UART_LSR_* bitmask of states to ignore (also based on termios)
224 * @break_ctl: if set, port is 'sending break' to remote
225 * @write_only: self-explanatory
226 * @overrun: previous rx was lost (partially or completely)
227 * @loopback: if set, port is in loopback mode
228 * @flags: atomic bit flags
229 * bit 0: IN_TX - gate to allow only one cpu to send from the dma fifo
230 * at a time.
231 * bit 1: STOP_TX - force tx to exit while sending
232 * @peer: rcu-pointer to associated fwtty_peer (if attached)
233 * NULL if no peer attached
234 * @icount: predefined statistics reported by the TIOCGICOUNT ioctl
235 * @stats: additional statistics reported in /proc/tty/driver/firewire_serial
236 */
237 struct fwtty_port {
238 struct tty_port port;
239 struct device *device;
240 unsigned index;
241 struct fw_serial *serial;
242 struct fw_address_handler rx_handler;
243
244 struct fwconsole_ops *fwcon_ops;
245 void *con_data;
246
247 wait_queue_head_t wait_tx;
248 struct delayed_work emit_breaks;
249 unsigned cps;
250 unsigned long break_last;
251
252 struct work_struct hangup;
253
254 unsigned mstatus;
255
256 spinlock_t lock;
257 unsigned mctrl;
258 struct delayed_work drain;
259 struct dma_fifo tx_fifo;
260 int max_payload;
261 unsigned status_mask;
262 unsigned ignore_mask;
263 unsigned break_ctl:1,
264 write_only:1,
265 overrun:1,
266 loopback:1;
267 unsigned long flags;
268
269 struct fwtty_peer __rcu *peer;
270
271 struct async_icount icount;
272 struct stats stats;
273 };
274
275 #define to_port(ptr, field) (container_of(ptr, struct fwtty_port, field))
276
277 /* bit #s for flags field */
278 #define IN_TX 0
279 #define STOP_TX 1
280
281 /* bitmasks for special mctrl/mstatus bits */
282 #define OOB_RX_THROTTLE 0x00010000
283 #define MCTRL_RSRVD 0x000e0000
284 #define OOB_TX_THROTTLE 0x00100000
285 #define MSTATUS_RSRVD 0x00e00000
286
287 #define MCTRL_MASK (TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 | TIOCM_OUT2 | \
288 TIOCM_LOOP | OOB_RX_THROTTLE | MCTRL_RSRVD)
289
290 /* XXX even every 1/50th secs. may be unnecessarily accurate */
291 /* delay in jiffies between brk emits */
292 #define FREQ_BREAKS (HZ / 50)
293
294 /* Ports are allocated in blocks of num_ports for each fw_card */
295 #define MAX_CARD_PORTS CONFIG_FWTTY_MAX_CARD_PORTS
296 #define MAX_TOTAL_PORTS CONFIG_FWTTY_MAX_TOTAL_PORTS
297
298 /* tuning parameters */
299 #define FWTTY_PORT_TXFIFO_LEN 4096
300 #define FWTTY_PORT_MAX_PEND_DMA 8 /* costs a cache line per pend */
301 #define DRAIN_THRESHOLD 1024
302 #define MAX_ASYNC_PAYLOAD 4096 /* ohci-defined limit */
303 #define WRITER_MINIMUM 128
304 /* TODO: how to set watermark to AR context size? see fwtty_rx() */
305 #define HIGH_WATERMARK 32768 /* AR context is 32K */
306
307 /*
308 * Size of bus addr region above 4GB used per port as the recv addr
309 * - must be at least as big as the MAX_ASYNC_PAYLOAD
310 */
311 #define FWTTY_PORT_RXFIFO_LEN MAX_ASYNC_PAYLOAD
312
313 /**
314 * fw_serial: aggregate used to associate tty ports with specific fw_card
315 * @card: fw_card associated with this fw_serial device (1:1 association)
316 * @kref: reference-counted multi-port management allows delayed destroy
317 * @self: local unit device as 'peer'. Not valid until local unit device
318 * is enumerated.
319 * @list: link for insertion into fwserial_list
320 * @peer_list: list of local & remote unit devices attached to this card
321 * @ports: fixed array of tty_ports provided by this serial device
322 */
323 struct fw_serial {
324 struct fw_card *card;
325 struct kref kref;
326
327 struct dentry *debugfs;
328 struct fwtty_peer *self;
329
330 struct list_head list;
331 struct list_head peer_list;
332
333 struct fwtty_port *ports[MAX_CARD_PORTS];
334 };
335
336 #define to_serial(ptr, field) (container_of(ptr, struct fw_serial, field))
337
338 #define TTY_DEV_NAME "fwtty" /* ttyFW was taken */
339 static const char tty_dev_name[] = TTY_DEV_NAME;
340 static const char loop_dev_name[] = "fwloop";
341
342 extern struct tty_driver *fwtty_driver;
343
344 struct fwtty_port *fwtty_port_get(unsigned index);
345 void fwtty_port_put(struct fwtty_port *port);
346
fwtty_bind_console(struct fwtty_port * port,struct fwconsole_ops * fwcon_ops,void * data)347 static inline void fwtty_bind_console(struct fwtty_port *port,
348 struct fwconsole_ops *fwcon_ops,
349 void *data)
350 {
351 port->con_data = data;
352 port->fwcon_ops = fwcon_ops;
353 }
354
355 /*
356 * Returns the max send async payload size in bytes based on the unit device
357 * link speed. Self-limiting asynchronous bandwidth (via reducing the payload)
358 * is not necessary and does not work, because
359 * 1) asynchronous traffic will absorb all available bandwidth (less that
360 * being used for isochronous traffic)
361 * 2) isochronous arbitration always wins.
362 */
link_speed_to_max_payload(unsigned speed)363 static inline int link_speed_to_max_payload(unsigned speed)
364 {
365 /* Max async payload is 4096 - see IEEE 1394-2008 tables 6-4, 16-18 */
366 return min(512 << speed, 4096);
367 }
368
369 #endif /* _FIREWIRE_FWSERIAL_H */
370