xref: /netbsd-src/sys/dev/ic/isp_tpublic.h (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /* $NetBSD: isp_tpublic.h,v 1.3 2000/05/13 16:53:04 he Exp $ */
2 /*
3  * Qlogic ISP Host Adapter Public Target Interface Structures && Routines
4  *---------------------------------------
5  * Copyright (c) 2000 by Matthew Jacob
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions, and the following disclaimer,
13  *    without modification, immediately at the beginning of the file.
14  * 2. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * Matthew Jacob
30  * Feral Software
31  * mjacob@feral.com
32  */
33 
34 /*
35  * Required software target mode message and event handling structures.
36  *
37  * The message and event structures are used by the MI layer
38  * to propagate messages and events upstream.
39  */
40 
41 #ifndef	IN_MSGLEN
42 #define	IN_MSGLEN	8
43 #endif
44 typedef struct {
45 	void *		nt_hba;			/* HBA tag */
46 	u_int64_t	nt_iid;			/* inititator id */
47 	u_int64_t	nt_tgt;			/* target id */
48 	u_int64_t	nt_lun;			/* logical unit */
49 	u_int8_t	nt_bus;			/* bus */
50 	u_int8_t	nt_tagtype;		/* tag type */
51 	u_int16_t	nt_tagval;		/* tag value */
52 	u_int8_t	nt_msg[IN_MSGLEN];	/* message content */
53 } tmd_msg_t;
54 
55 typedef struct {
56 	void *		ev_hba;			/* HBA tag */
57 	u_int16_t	ev_bus;			/* bus */
58 	u_int16_t	ev_event;		/* type of async event */
59 } tmd_event_t;
60 
61 /*
62  * Suggested Software Target Mode Command Handling structure.
63  *
64  * A note about terminology:
65  *
66  *   MD stands for "Machine Dependent".
67  *
68  *    This driver is structured in three layers: Outer MD, core, and inner MD.
69  *    The latter also is bus dependent (i.e., is cognizant of PCI bus issues
70  *    as well as platform issues).
71  *
72  *
73  *   "Outer Layer" means "Other Module"
74  *
75  *    Some additional module that actually implements SCSI target command
76  *    policy is the recipient of incoming commands and the source of the
77  *    disposition for them.
78  *
79  * The command structure below is one suggested possible MD command structure,
80  * but since the handling of thbis is entirely in the MD layer, there is
81  * no explicit or implicit requirement that it be used.
82  *
83  * The cd_private tag should be used by the MD layer to keep a free list
84  * of these structures. Code outside of this driver can then use this
85  * as an to identify it's own unit structures. That is, when not on the MD
86  * layer's freelist, the MD layer should shove into it the identifier
87  * that the outer layer has for it- passed in on an initial QIN_HBA_REG
88  * call (see below).
89  *
90  * The cd_hba tag is a tag that uniquely identifies the HBA this target
91  * mode command is coming from. The outer layer has to pass this back
92  * unchanged to avoid chaos.
93  *
94  * The cd_iid, cd_tgt, cd_lun and cd_bus tags are used to identify the
95  * id of the initiator who sent us a command, the target claim to be, the
96  * lun on the target we claim to be, and the bus instance (for multiple
97  * bus host adapters) that this applies to (consider it an extra Port
98  * parameter). The iid, tgt and lun values are deliberately chosen to be
99  * fat so that, for example, World Wide Names can be used instead of
100  * the units that the Qlogic firmware uses (in the case where the MD
101  * layer maintains a port database, for example).
102  *
103  * The cd_tagtype field specifies what kind of command tag has been
104  * sent with the command. The cd_tagval is the tag's value.
105  *
106  * N.B.: when the MD layer sends this command to outside software
107  * the outside software likely *MUST* return the same cd_tagval that
108  * was in place because this value is likely what the Qlogic f/w uses
109  * to identify a command.
110  *
111  * The cd_cdb contains storage for the passed in command descriptor block.
112  * This is the maximum size we can get out of the Qlogic f/w. There's no
113  * passed in length because whoever decodes the command to act upon it
114  * will know what the appropriate length is.
115  *
116  * The tag cd_lflags are the flags set by the MD driver when it gets
117  * command incoming or when it needs to inform any outside entities
118  * that the last requested action failed.
119  *
120  * The tag cd_hflags should be set by any outside software to indicate
121  * the validity of sense and status fields (defined below) and to indicate
122  * the direction data is expected to move. It is an error to have both
123  * CDFH_DATA_IN and CDFH_DATA_OUT set.
124  *
125  * If the CDFH_STSVALID flag is set, the command should be completed (after
126  * sending any data and/or status). If CDFH_SNSVALID is set and the MD layer
127  * can also handle sending the associated sense data (either back with an
128  * FCP RESPONSE IU for Fibre Channel or otherwise automatically handling a
129  * REQUEST SENSE from the initator for this target/lun), the MD layer will
130  * set the CDFL_SENTSENSE flag on successful transmission of the sense data.
131  * It is an error for the CDFH_SNSVALID bit to be set and CDFH_STSVALID not
132  * to be set. It is an error for the CDFH_SNSVALID be set and the associated
133  * SCSI status (cd_scsi_status) not be set to CHECK CONDITON.
134  *
135  * The tag cd_data points to a data segment to either be filled or
136  * read from depending on the direction of data movement. The tag
137  * is undefined if no data direction is set. The MD layer and outer
138  * layers must agree on the meaning of cd_data.
139  *
140  * The tag cd_totlen is the total data amount expected to be moved
141  * over the life of the command. It *may* be set by the MD layer, possibly
142  * from the datalen field of an FCP CMND IU unit. If it shows up in the outer
143  * layers set to zero and the CDB indicates data should be moved, the outer
144  * layer should set it to the amount expected to be moved.
145  *
146  * The tag cd_resid should be the total residual of data not transferred.
147  * The outer layers need to set this at the begining of command processing
148  * to equal cd_totlen. As data is successfully moved, this value is decreased.
149  * At the end of a command, any nonzero residual indicates the number of bytes
150  * requested but not moved. XXXXXXXXXXXXXXXXXXXXXXX TOO VAGUE!!!
151  *
152  * The tag cd_xfrlen is the length of the currently active data transfer.
153  * This allows several interations between any outside software and the
154  * MD layer to move data.
155  *
156  * The reason that total length and total residual have to be tracked
157  * is that fibre channel FCP DATA IU units have to have a relative
158  * offset field.
159  *
160  * N.B.: there is no necessary 1-to-1 correspondence between any one
161  * data transfer segment and the number of CTIOs that will be generated
162  * satisfy the current data transfer segment. It's not also possible to
163  * predict how big a transfer can be before it will be 'too big'. Be
164  * reasonable- a 64KB transfer is 'reasonable'. A 1MB transfer may not
165  * be. A 32MB transfer is unreasonable. The problem here has to do with
166  * how CTIOs can be used to map passed data pointers. In systems which
167  * have page based scatter-gather requirements, each PAGESIZEd chunk will
168  * consume one data segment descriptor- you get 3 or 4 of them per CTIO.
169  * The size of the REQUEST QUEUE you drop a CTIO onto is finite (typically
170  * it's 256, but on some systems it's even smaller, and note you have to
171  * sure this queue with the initiator side of this driver).
172  *
173  * The tags cd_sense and cd_scsi_status are pretty obvious.
174  *
175  * The tag cd_error is to communicate between the MD layer and outer software
176  * the current error conditions.
177  *
178  * The tag cd_reserved pads out the structure to 128 bytes.
179  */
180 
181 #ifndef	_LP64
182 #if	defined(__alpha__) || defined(__sparcv9cpu) || defined(__sparc_v9__)
183 #define	_LP64
184 #endif
185 #endif
186 
187 #ifndef	_TMD_PAD_LEN
188 #ifdef	_LP64
189 #define	_TMD_PAD_LEN	12
190 #else
191 #define	_TMD_PAD_LEN	24
192 #endif
193 #endif
194 #ifndef	ATIO_CDBLEN
195 #define	ATIO_CDBLEN	26
196 #endif
197 #ifndef	QLTM_SENSELEN
198 #define	QLTM_SENSELEN	18
199 #endif
200 typedef struct tmd_cmd {
201 	void *			cd_private;	/* layer private data */
202 	void *			cd_hba;		/* HBA tag */
203 	void *			cd_data;	/* 'pointer' to data */
204 	u_int64_t		cd_iid;		/* initiator ID */
205 	u_int64_t		cd_tgt;		/* target id */
206 	u_int64_t		cd_lun;		/* logical unit */
207 	u_int8_t		cd_bus;		/* bus */
208 	u_int8_t		cd_tagtype;	/* tag type */
209 	u_int16_t		cd_tagval;	/* tag value */
210 	u_int8_t		cd_cdb[ATIO_CDBLEN];	/* Command */
211 	u_int8_t		cd_lflags;	/* flags lower level sets */
212 	u_int8_t		cd_hflags;	/* flags higher level sets */
213 	u_int32_t		cd_totlen;	/* total data requirement */
214 	u_int32_t		cd_resid;	/* total data residual */
215 	u_int32_t		cd_xfrlen;	/* current data requirement */
216 	int32_t			cd_error;	/* current error */
217 	u_int8_t		cd_sense[QLTM_SENSELEN];
218 	u_int16_t		cd_scsi_status;	/* closing SCSI status */
219 	u_int8_t		cd_reserved[_TMD_PAD_LEN];
220 } tmd_cmd_t;
221 
222 #define	CDFL_BUSY	0x01		/* this command is not on a free list */
223 #define	CDFL_NODISC	0x02		/* disconnects disabled */
224 #define	CDFL_SENTSENSE	0x04		/* last action sent sense data */
225 #define	CDFL_SENTSTATUS	0x08		/* last action sent status */
226 #define	CDFL_ERROR	0x10		/* last action ended in error */
227 #define	CDFL_PRIVATE_0	0x80		/* private layer flags */
228 
229 #define	CDFH_SNSVALID	0x01		/* sense data valid */
230 #define	CDFH_STSVALID	0x02		/* status valid */
231 #define	CDFH_NODATA	0x00		/* no data transfer expected */
232 #define	CDFH_DATA_IN	0x04		/* target (us) -> initiator (them) */
233 #define	CDFH_DATA_OUT	0x08		/* initiator (them) -> target (us) */
234 #define	CDFH_DATA_MASK	0x0C		/* mask to cover data direction */
235 #define	CDFH_PRIVATE_0	0x80		/* private layer flags */
236 
237 /*
238  * Action codes set by the Qlogic MD target driver for
239  * the external layer to figure out what to do with.
240  */
241 typedef enum {
242 	QOUT_HBA_REG=0,	/* the argument is a pointer to a hba_register_t */
243 	QOUT_TMD_START,	/* the argument is a pointer to a tmd_cmd_t */
244 	QOUT_TMD_DONE,	/* the argument is a pointer to a tmd_cmd_t */
245 	QOUT_TEVENT,	/* the argument is a pointer to a tmd_event_t */
246 	QOUT_TMSG,	/* the argument is a pointer to a tmd_msg_t */
247 	QOUT_HBA_UNREG	/* the argument is a pointer to a hba_register_t */
248 } tact_e;
249 
250 /*
251  * Action codes set by the external layer for the
252  * MD Qlogic driver to figure out what to do with.
253  */
254 typedef enum {
255 	QIN_HBA_REG=6,	/* the argument is a pointer to a hba_register_t */
256 	QIN_ENABLE,	/* the argument is a pointer to a tmd_cmd_t */
257 	QIN_DISABLE,	/* the argument is a pointer to a tmd_cmd_t */
258 	QIN_TMD_CONT,	/* the argument is a pointer to a tmd_cmd_t */
259 	QIN_TMD_FIN,	/* the argument is a pointer to a done tmd_cmd_t */
260 	QIN_HBA_UNREG	/* the argument is a pointer to a hba_register_t */
261 } qact_e;
262 
263 /*
264  * A word about the START/CONT/DONE/FIN dance:
265  *
266  *	When the HBA is enabled for receiving commands, one may	show up
267  *	without notice. When that happens, the Qlogic target mode driver
268  *	gets a tmd_cmd_t, fills it with the info that just arrived, and
269  *	calls the outer layer with a QIN_TMD_START code and pointer to
270  *	the tmd_cmd_t.
271  *
272  *	The outer layer decodes the command, fetches data, prepares stuff,
273  *	whatever, and starts by passing back the pointer with a QIN_TMD_CONT
274  *	code which causes the Qlogic target mode driver to generate CTIOs to
275  *	satisfy whatever action needs to be taken. When those CTIOs complete,
276  *	the Qlogic target driver sends the pointer to the cmd_tmd_t back with
277  *	a QOUT_TMD_DONE code. This repeats for as long as necessary.
278  *
279  *	The outer layer signals it wants to end the command by settings within
280  *	the tmd_cmd_t itself. When the final QIN_TMD_CONT is reported completed,
281  *	the outer layer frees the tmd_cmd_t by sending the pointer to it
282  *	back with a QIN_TMD_FIN code.
283  *
284  *	The graph looks like:
285  *
286  *	QOUT_TMD_START -> [ QIN_TMD_CONT -> QOUT_TMD_DONE ] * -> QIN_TMD_FIN.
287  *
288  */
289 
290 /*
291  * A word about ENABLE/DISABLE: the argument is a pointer to an tmd_cmd_t
292  * with cd_hba, cd_bus, cd_tgt and cd_lun filled out. If an error occurs
293  * in either enabling or disabling the described lun, cd_lflags is set
294  * with CDFL_ERROR.
295  *
296  * Logical unit zero must be the first enabled and the last disabled.
297  */
298 
299 /*
300  * Target handler functions.
301  * The MD target handler function (the outer layer calls this)
302  * should be be prototyped like:
303  *
304  *	void target_action(qact_e, void *arg)
305  *
306  * The outer layer target handler function (the MD layer calls this)
307  * should be be prototyped like:
308  *
309  *	void system_action(tact_e, void *arg)
310  */
311 
312 /*
313  * This structure is used to register to other software modules the
314  * binding of an HBA identifier, driver name and instance and the
315  * lun width capapbilities of this target driver. It's up to each
316  * platform to figure out how it wants to do this, but a typical
317  * sequence would be for the MD layer to find some external module's
318  * entry point and start by sending a QOUT_HBA_REG with info filled
319  * in, and the external module to call back with a QIN_HBA_REG that
320  * passes back the corresponding information.
321  */
322 typedef struct {
323 	void *	r_identity;
324 	char	r_name[8];
325 	int	r_inst;
326 	int	r_lunwidth;
327 	int	r_buswidth;
328 	void   (*r_action) __P((int, void *));
329 } hba_register_t;
330