xref: /openbmc/linux/drivers/scsi/esp_scsi.h (revision e3b9f1e8)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* esp_scsi.h: Defines and structures for the ESP driver.
3  *
4  * Copyright (C) 2007 David S. Miller (davem@davemloft.net)
5  */
6 
7 #ifndef _ESP_SCSI_H
8 #define _ESP_SCSI_H
9 
10 					/* Access    Description      Offset */
11 #define ESP_TCLOW	0x00UL		/* rw  Low bits transfer count 0x00  */
12 #define ESP_TCMED	0x01UL		/* rw  Mid bits transfer count 0x04  */
13 #define ESP_FDATA	0x02UL		/* rw  FIFO data bits          0x08  */
14 #define ESP_CMD		0x03UL		/* rw  SCSI command bits       0x0c  */
15 #define ESP_STATUS	0x04UL		/* ro  ESP status register     0x10  */
16 #define ESP_BUSID	ESP_STATUS	/* wo  BusID for sel/resel     0x10  */
17 #define ESP_INTRPT	0x05UL		/* ro  Kind of interrupt       0x14  */
18 #define ESP_TIMEO	ESP_INTRPT	/* wo  Timeout for sel/resel   0x14  */
19 #define ESP_SSTEP	0x06UL		/* ro  Sequence step register  0x18  */
20 #define ESP_STP		ESP_SSTEP	/* wo  Transfer period/sync    0x18  */
21 #define ESP_FFLAGS	0x07UL		/* ro  Bits current FIFO info  0x1c  */
22 #define ESP_SOFF	ESP_FFLAGS	/* wo  Sync offset             0x1c  */
23 #define ESP_CFG1	0x08UL		/* rw  First cfg register      0x20  */
24 #define ESP_CFACT	0x09UL		/* wo  Clock conv factor       0x24  */
25 #define ESP_STATUS2	ESP_CFACT	/* ro  HME status2 register    0x24  */
26 #define ESP_CTEST	0x0aUL		/* wo  Chip test register      0x28  */
27 #define ESP_CFG2	0x0bUL		/* rw  Second cfg register     0x2c  */
28 #define ESP_CFG3	0x0cUL		/* rw  Third cfg register      0x30  */
29 #define ESP_CFG4	0x0dUL		/* rw  Fourth cfg register     0x34  */
30 #define ESP_TCHI	0x0eUL		/* rw  High bits transf count  0x38  */
31 #define ESP_UID		ESP_TCHI	/* ro  Unique ID code          0x38  */
32 #define FAS_RLO		ESP_TCHI	/* rw  HME extended counter    0x38  */
33 #define ESP_FGRND	0x0fUL		/* rw  Data base for fifo      0x3c  */
34 #define FAS_RHI		ESP_FGRND	/* rw  HME extended counter    0x3c  */
35 
36 #define SBUS_ESP_REG_SIZE	0x40UL
37 
38 /* Bitfield meanings for the above registers. */
39 
40 /* ESP config reg 1, read-write, found on all ESP chips */
41 #define ESP_CONFIG1_ID        0x07      /* My BUS ID bits */
42 #define ESP_CONFIG1_CHTEST    0x08      /* Enable ESP chip tests */
43 #define ESP_CONFIG1_PENABLE   0x10      /* Enable parity checks */
44 #define ESP_CONFIG1_PARTEST   0x20      /* Parity test mode enabled? */
45 #define ESP_CONFIG1_SRRDISAB  0x40      /* Disable SCSI reset reports */
46 #define ESP_CONFIG1_SLCABLE   0x80      /* Enable slow cable mode */
47 
48 /* ESP config reg 2, read-write, found only on esp100a+esp200+esp236 chips */
49 #define ESP_CONFIG2_DMAPARITY 0x01      /* enable DMA Parity (200,236) */
50 #define ESP_CONFIG2_REGPARITY 0x02      /* enable reg Parity (200,236) */
51 #define ESP_CONFIG2_BADPARITY 0x04      /* Bad parity target abort  */
52 #define ESP_CONFIG2_SCSI2ENAB 0x08      /* Enable SCSI-2 features (tgtmode) */
53 #define ESP_CONFIG2_HI        0x10      /* High Impedance DREQ ???  */
54 #define ESP_CONFIG2_HMEFENAB  0x10      /* HME features enable */
55 #define ESP_CONFIG2_BCM       0x20      /* Enable byte-ctrl (236)   */
56 #define ESP_CONFIG2_DISPINT   0x20      /* Disable pause irq (hme) */
57 #define ESP_CONFIG2_FENAB     0x40      /* Enable features (fas100,216) */
58 #define ESP_CONFIG2_SPL       0x40      /* Enable status-phase latch (236) */
59 #define ESP_CONFIG2_MKDONE    0x40      /* HME magic feature */
60 #define ESP_CONFIG2_HME32     0x80      /* HME 32 extended */
61 #define ESP_CONFIG2_MAGIC     0xe0      /* Invalid bits... */
62 
63 /* ESP config register 3 read-write, found only esp236+fas236+fas100a+hme chips */
64 #define ESP_CONFIG3_FCLOCK    0x01     /* FAST SCSI clock rate (esp100a/hme) */
65 #define ESP_CONFIG3_TEM       0x01     /* Enable thresh-8 mode (esp/fas236)  */
66 #define ESP_CONFIG3_FAST      0x02     /* Enable FAST SCSI     (esp100a/hme) */
67 #define ESP_CONFIG3_ADMA      0x02     /* Enable alternate-dma (esp/fas236)  */
68 #define ESP_CONFIG3_TENB      0x04     /* group2 SCSI2 support (esp100a/hme) */
69 #define ESP_CONFIG3_SRB       0x04     /* Save residual byte   (esp/fas236)  */
70 #define ESP_CONFIG3_TMS       0x08     /* Three-byte msg's ok  (esp100a/hme) */
71 #define ESP_CONFIG3_FCLK      0x08     /* Fast SCSI clock rate (esp/fas236)  */
72 #define ESP_CONFIG3_IDMSG     0x10     /* ID message checking  (esp100a/hme) */
73 #define ESP_CONFIG3_FSCSI     0x10     /* Enable FAST SCSI     (esp/fas236)  */
74 #define ESP_CONFIG3_GTM       0x20     /* group2 SCSI2 support (esp/fas236)  */
75 #define ESP_CONFIG3_IDBIT3    0x20     /* Bit 3 of HME SCSI-ID (hme)         */
76 #define ESP_CONFIG3_TBMS      0x40     /* Three-byte msg's ok  (esp/fas236)  */
77 #define ESP_CONFIG3_EWIDE     0x40     /* Enable Wide-SCSI     (hme)         */
78 #define ESP_CONFIG3_IMS       0x80     /* ID msg chk'ng        (esp/fas236)  */
79 #define ESP_CONFIG3_OBPUSH    0x80     /* Push odd-byte to dma (hme)         */
80 
81 /* ESP config register 4 read-write, found only on am53c974 chips */
82 #define ESP_CONFIG4_RADE      0x04     /* Active negation */
83 #define ESP_CONFIG4_RAE       0x08     /* Active negation on REQ and ACK */
84 #define ESP_CONFIG4_PWD       0x20     /* Reduced power feature */
85 #define ESP_CONFIG4_GE0       0x40     /* Glitch eater bit 0 */
86 #define ESP_CONFIG4_GE1       0x80     /* Glitch eater bit 1 */
87 
88 #define ESP_CONFIG_GE_12NS    (0)
89 #define ESP_CONFIG_GE_25NS    (ESP_CONFIG_GE1)
90 #define ESP_CONFIG_GE_35NS    (ESP_CONFIG_GE0)
91 #define ESP_CONFIG_GE_0NS     (ESP_CONFIG_GE0 | ESP_CONFIG_GE1)
92 
93 /* ESP command register read-write */
94 /* Group 1 commands:  These may be sent at any point in time to the ESP
95  *                    chip.  None of them can generate interrupts 'cept
96  *                    the "SCSI bus reset" command if you have not disabled
97  *                    SCSI reset interrupts in the config1 ESP register.
98  */
99 #define ESP_CMD_NULL          0x00     /* Null command, ie. a nop */
100 #define ESP_CMD_FLUSH         0x01     /* FIFO Flush */
101 #define ESP_CMD_RC            0x02     /* Chip reset */
102 #define ESP_CMD_RS            0x03     /* SCSI bus reset */
103 
104 /* Group 2 commands:  ESP must be an initiator and connected to a target
105  *                    for these commands to work.
106  */
107 #define ESP_CMD_TI            0x10     /* Transfer Information */
108 #define ESP_CMD_ICCSEQ        0x11     /* Initiator cmd complete sequence */
109 #define ESP_CMD_MOK           0x12     /* Message okie-dokie */
110 #define ESP_CMD_TPAD          0x18     /* Transfer Pad */
111 #define ESP_CMD_SATN          0x1a     /* Set ATN */
112 #define ESP_CMD_RATN          0x1b     /* De-assert ATN */
113 
114 /* Group 3 commands:  ESP must be in the MSGOUT or MSGIN state and be connected
115  *                    to a target as the initiator for these commands to work.
116  */
117 #define ESP_CMD_SMSG          0x20     /* Send message */
118 #define ESP_CMD_SSTAT         0x21     /* Send status */
119 #define ESP_CMD_SDATA         0x22     /* Send data */
120 #define ESP_CMD_DSEQ          0x23     /* Discontinue Sequence */
121 #define ESP_CMD_TSEQ          0x24     /* Terminate Sequence */
122 #define ESP_CMD_TCCSEQ        0x25     /* Target cmd cmplt sequence */
123 #define ESP_CMD_DCNCT         0x27     /* Disconnect */
124 #define ESP_CMD_RMSG          0x28     /* Receive Message */
125 #define ESP_CMD_RCMD          0x29     /* Receive Command */
126 #define ESP_CMD_RDATA         0x2a     /* Receive Data */
127 #define ESP_CMD_RCSEQ         0x2b     /* Receive cmd sequence */
128 
129 /* Group 4 commands:  The ESP must be in the disconnected state and must
130  *                    not be connected to any targets as initiator for
131  *                    these commands to work.
132  */
133 #define ESP_CMD_RSEL          0x40     /* Reselect */
134 #define ESP_CMD_SEL           0x41     /* Select w/o ATN */
135 #define ESP_CMD_SELA          0x42     /* Select w/ATN */
136 #define ESP_CMD_SELAS         0x43     /* Select w/ATN & STOP */
137 #define ESP_CMD_ESEL          0x44     /* Enable selection */
138 #define ESP_CMD_DSEL          0x45     /* Disable selections */
139 #define ESP_CMD_SA3           0x46     /* Select w/ATN3 */
140 #define ESP_CMD_RSEL3         0x47     /* Reselect3 */
141 
142 /* This bit enables the ESP's DMA on the SBus */
143 #define ESP_CMD_DMA           0x80     /* Do DMA? */
144 
145 /* ESP status register read-only */
146 #define ESP_STAT_PIO          0x01     /* IO phase bit */
147 #define ESP_STAT_PCD          0x02     /* CD phase bit */
148 #define ESP_STAT_PMSG         0x04     /* MSG phase bit */
149 #define ESP_STAT_PMASK        0x07     /* Mask of phase bits */
150 #define ESP_STAT_TDONE        0x08     /* Transfer Completed */
151 #define ESP_STAT_TCNT         0x10     /* Transfer Counter Is Zero */
152 #define ESP_STAT_PERR         0x20     /* Parity error */
153 #define ESP_STAT_SPAM         0x40     /* Real bad error */
154 /* This indicates the 'interrupt pending' condition on esp236, it is a reserved
155  * bit on other revs of the ESP.
156  */
157 #define ESP_STAT_INTR         0x80             /* Interrupt */
158 
159 /* The status register can be masked with ESP_STAT_PMASK and compared
160  * with the following values to determine the current phase the ESP
161  * (at least thinks it) is in.  For our purposes we also add our own
162  * software 'done' bit for our phase management engine.
163  */
164 #define ESP_DOP   (0)                                       /* Data Out  */
165 #define ESP_DIP   (ESP_STAT_PIO)                            /* Data In   */
166 #define ESP_CMDP  (ESP_STAT_PCD)                            /* Command   */
167 #define ESP_STATP (ESP_STAT_PCD|ESP_STAT_PIO)               /* Status    */
168 #define ESP_MOP   (ESP_STAT_PMSG|ESP_STAT_PCD)              /* Message Out */
169 #define ESP_MIP   (ESP_STAT_PMSG|ESP_STAT_PCD|ESP_STAT_PIO) /* Message In */
170 
171 /* HME only: status 2 register */
172 #define ESP_STAT2_SCHBIT      0x01 /* Upper bits 3-7 of sstep enabled */
173 #define ESP_STAT2_FFLAGS      0x02 /* The fifo flags are now latched */
174 #define ESP_STAT2_XCNT        0x04 /* The transfer counter is latched */
175 #define ESP_STAT2_CREGA       0x08 /* The command reg is active now */
176 #define ESP_STAT2_WIDE        0x10 /* Interface on this adapter is wide */
177 #define ESP_STAT2_F1BYTE      0x20 /* There is one byte at top of fifo */
178 #define ESP_STAT2_FMSB        0x40 /* Next byte in fifo is most significant */
179 #define ESP_STAT2_FEMPTY      0x80 /* FIFO is empty */
180 
181 /* ESP interrupt register read-only */
182 #define ESP_INTR_S            0x01     /* Select w/o ATN */
183 #define ESP_INTR_SATN         0x02     /* Select w/ATN */
184 #define ESP_INTR_RSEL         0x04     /* Reselected */
185 #define ESP_INTR_FDONE        0x08     /* Function done */
186 #define ESP_INTR_BSERV        0x10     /* Bus service */
187 #define ESP_INTR_DC           0x20     /* Disconnect */
188 #define ESP_INTR_IC           0x40     /* Illegal command given */
189 #define ESP_INTR_SR           0x80     /* SCSI bus reset detected */
190 
191 /* ESP sequence step register read-only */
192 #define ESP_STEP_VBITS        0x07     /* Valid bits */
193 #define ESP_STEP_ASEL         0x00     /* Selection&Arbitrate cmplt */
194 #define ESP_STEP_SID          0x01     /* One msg byte sent */
195 #define ESP_STEP_NCMD         0x02     /* Was not in command phase */
196 #define ESP_STEP_PPC          0x03     /* Early phase chg caused cmnd
197                                         * bytes to be lost
198                                         */
199 #define ESP_STEP_FINI4        0x04     /* Command was sent ok */
200 
201 /* Ho hum, some ESP's set the step register to this as well... */
202 #define ESP_STEP_FINI5        0x05
203 #define ESP_STEP_FINI6        0x06
204 #define ESP_STEP_FINI7        0x07
205 
206 /* ESP chip-test register read-write */
207 #define ESP_TEST_TARG         0x01     /* Target test mode */
208 #define ESP_TEST_INI          0x02     /* Initiator test mode */
209 #define ESP_TEST_TS           0x04     /* Tristate test mode */
210 
211 /* ESP unique ID register read-only, found on fas236+fas100a only */
212 #define ESP_UID_F100A         0x00     /* ESP FAS100A  */
213 #define ESP_UID_F236          0x02     /* ESP FAS236   */
214 #define ESP_UID_REV           0x07     /* ESP revision */
215 #define ESP_UID_FAM           0xf8     /* ESP family   */
216 
217 /* ESP fifo flags register read-only */
218 /* Note that the following implies a 16 byte FIFO on the ESP. */
219 #define ESP_FF_FBYTES         0x1f     /* Num bytes in FIFO */
220 #define ESP_FF_ONOTZERO       0x20     /* offset ctr not zero (esp100) */
221 #define ESP_FF_SSTEP          0xe0     /* Sequence step */
222 
223 /* ESP clock conversion factor register write-only */
224 #define ESP_CCF_F0            0x00     /* 35.01MHz - 40MHz */
225 #define ESP_CCF_NEVER         0x01     /* Set it to this and die */
226 #define ESP_CCF_F2            0x02     /* 10MHz */
227 #define ESP_CCF_F3            0x03     /* 10.01MHz - 15MHz */
228 #define ESP_CCF_F4            0x04     /* 15.01MHz - 20MHz */
229 #define ESP_CCF_F5            0x05     /* 20.01MHz - 25MHz */
230 #define ESP_CCF_F6            0x06     /* 25.01MHz - 30MHz */
231 #define ESP_CCF_F7            0x07     /* 30.01MHz - 35MHz */
232 
233 /* HME only... */
234 #define ESP_BUSID_RESELID     0x10
235 #define ESP_BUSID_CTR32BIT    0x40
236 
237 #define ESP_BUS_TIMEOUT        250     /* In milli-seconds */
238 #define ESP_TIMEO_CONST       8192
239 #define ESP_NEG_DEFP(mhz, cfact) \
240         ((ESP_BUS_TIMEOUT * ((mhz) / 1000)) / (8192 * (cfact)))
241 #define ESP_HZ_TO_CYCLE(hertz)  ((1000000000) / ((hertz) / 1000))
242 #define ESP_TICK(ccf, cycle)  ((7682 * (ccf) * (cycle) / 1000))
243 
244 /* For slow to medium speed input clock rates we shoot for 5mb/s, but for high
245  * input clock rates we try to do 10mb/s although I don't think a transfer can
246  * even run that fast with an ESP even with DMA2 scatter gather pipelining.
247  */
248 #define SYNC_DEFP_SLOW            0x32   /* 5mb/s  */
249 #define SYNC_DEFP_FAST            0x19   /* 10mb/s */
250 
251 struct esp_cmd_priv {
252 	union {
253 		dma_addr_t	dma_addr;
254 		int		num_sg;
255 	} u;
256 
257 	int			cur_residue;
258 	struct scatterlist	*cur_sg;
259 	int			tot_residue;
260 };
261 #define ESP_CMD_PRIV(CMD)	((struct esp_cmd_priv *)(&(CMD)->SCp))
262 
263 enum esp_rev {
264 	ESP100     = 0x00,  /* NCR53C90 - very broken */
265 	ESP100A    = 0x01,  /* NCR53C90A */
266 	ESP236     = 0x02,
267 	FAS236     = 0x03,
268 	FAS100A    = 0x04,
269 	FAST       = 0x05,
270 	FASHME     = 0x06,
271 	PCSCSI     = 0x07,  /* AM53c974 */
272 };
273 
274 struct esp_cmd_entry {
275 	struct list_head	list;
276 
277 	struct scsi_cmnd	*cmd;
278 
279 	unsigned int		saved_cur_residue;
280 	struct scatterlist	*saved_cur_sg;
281 	unsigned int		saved_tot_residue;
282 
283 	u8			flags;
284 #define ESP_CMD_FLAG_WRITE	0x01 /* DMA is a write */
285 #define ESP_CMD_FLAG_AUTOSENSE	0x04 /* Doing automatic REQUEST_SENSE */
286 #define ESP_CMD_FLAG_RESIDUAL	0x08 /* AM53c974 BLAST residual */
287 
288 	u8			tag[2];
289 	u8			orig_tag[2];
290 
291 	u8			status;
292 	u8			message;
293 
294 	unsigned char		*sense_ptr;
295 	unsigned char		*saved_sense_ptr;
296 	dma_addr_t		sense_dma;
297 
298 	struct completion	*eh_done;
299 };
300 
301 #define ESP_DEFAULT_TAGS	16
302 
303 #define ESP_MAX_TARGET		16
304 #define ESP_MAX_LUN		8
305 #define ESP_MAX_TAG		256
306 
307 struct esp_lun_data {
308 	struct esp_cmd_entry	*non_tagged_cmd;
309 	int			num_tagged;
310 	int			hold;
311 	struct esp_cmd_entry	*tagged_cmds[ESP_MAX_TAG];
312 };
313 
314 struct esp_target_data {
315 	/* These are the ESP_STP, ESP_SOFF, and ESP_CFG3 register values which
316 	 * match the currently negotiated settings for this target.  The SCSI
317 	 * protocol values are maintained in spi_{offset,period,wide}(starget).
318 	 */
319 	u8			esp_period;
320 	u8			esp_offset;
321 	u8			esp_config3;
322 
323 	u8			flags;
324 #define ESP_TGT_WIDE		0x01
325 #define ESP_TGT_DISCONNECT	0x02
326 #define ESP_TGT_NEGO_WIDE	0x04
327 #define ESP_TGT_NEGO_SYNC	0x08
328 #define ESP_TGT_CHECK_NEGO	0x40
329 #define ESP_TGT_BROKEN		0x80
330 
331 	/* When ESP_TGT_CHECK_NEGO is set, on the next scsi command to this
332 	 * device we will try to negotiate the following parameters.
333 	 */
334 	u8			nego_goal_period;
335 	u8			nego_goal_offset;
336 	u8			nego_goal_width;
337 	u8			nego_goal_tags;
338 
339 	struct scsi_target	*starget;
340 };
341 
342 struct esp_event_ent {
343 	u8			type;
344 #define ESP_EVENT_TYPE_EVENT	0x01
345 #define ESP_EVENT_TYPE_CMD	0x02
346 	u8			val;
347 
348 	u8			sreg;
349 	u8			seqreg;
350 	u8			sreg2;
351 	u8			ireg;
352 	u8			select_state;
353 	u8			event;
354 	u8			__pad;
355 };
356 
357 struct esp;
358 struct esp_driver_ops {
359 	/* Read and write the ESP 8-bit registers.  On some
360 	 * applications of the ESP chip the registers are at 4-byte
361 	 * instead of 1-byte intervals.
362 	 */
363 	void (*esp_write8)(struct esp *esp, u8 val, unsigned long reg);
364 	u8 (*esp_read8)(struct esp *esp, unsigned long reg);
365 
366 	/* Map and unmap DMA memory.  Eventually the driver will be
367 	 * converted to the generic DMA API as soon as SBUS is able to
368 	 * cope with that.  At such time we can remove this.
369 	 */
370 	dma_addr_t (*map_single)(struct esp *esp, void *buf,
371 				 size_t sz, int dir);
372 	int (*map_sg)(struct esp *esp, struct scatterlist *sg,
373 		      int num_sg, int dir);
374 	void (*unmap_single)(struct esp *esp, dma_addr_t addr,
375 			     size_t sz, int dir);
376 	void (*unmap_sg)(struct esp *esp, struct scatterlist *sg,
377 			 int num_sg, int dir);
378 
379 	/* Return non-zero if there is an IRQ pending.  Usually this
380 	 * status bit lives in the DMA controller sitting in front of
381 	 * the ESP.  This has to be accurate or else the ESP interrupt
382 	 * handler will not run.
383 	 */
384 	int (*irq_pending)(struct esp *esp);
385 
386 	/* Return the maximum allowable size of a DMA transfer for a
387 	 * given buffer.
388 	 */
389 	u32 (*dma_length_limit)(struct esp *esp, u32 dma_addr,
390 				u32 dma_len);
391 
392 	/* Reset the DMA engine entirely.  On return, ESP interrupts
393 	 * should be enabled.  Often the interrupt enabling is
394 	 * controlled in the DMA engine.
395 	 */
396 	void (*reset_dma)(struct esp *esp);
397 
398 	/* Drain any pending DMA in the DMA engine after a transfer.
399 	 * This is for writes to memory.
400 	 */
401 	void (*dma_drain)(struct esp *esp);
402 
403 	/* Invalidate the DMA engine after a DMA transfer.  */
404 	void (*dma_invalidate)(struct esp *esp);
405 
406 	/* Setup an ESP command that will use a DMA transfer.
407 	 * The 'esp_count' specifies what transfer length should be
408 	 * programmed into the ESP transfer counter registers, whereas
409 	 * the 'dma_count' is the length that should be programmed into
410 	 * the DMA controller.  Usually they are the same.  If 'write'
411 	 * is non-zero, this transfer is a write into memory.  'cmd'
412 	 * holds the ESP command that should be issued by calling
413 	 * scsi_esp_cmd() at the appropriate time while programming
414 	 * the DMA hardware.
415 	 */
416 	void (*send_dma_cmd)(struct esp *esp, u32 dma_addr, u32 esp_count,
417 			     u32 dma_count, int write, u8 cmd);
418 
419 	/* Return non-zero if the DMA engine is reporting an error
420 	 * currently.
421 	 */
422 	int (*dma_error)(struct esp *esp);
423 };
424 
425 #define ESP_MAX_MSG_SZ		8
426 #define ESP_EVENT_LOG_SZ	32
427 
428 #define ESP_QUICKIRQ_LIMIT	100
429 #define ESP_RESELECT_TAG_LIMIT	2500
430 
431 struct esp {
432 	void __iomem		*regs;
433 	void __iomem		*dma_regs;
434 
435 	const struct esp_driver_ops *ops;
436 
437 	struct Scsi_Host	*host;
438 	void			*dev;
439 
440 	struct esp_cmd_entry	*active_cmd;
441 
442 	struct list_head	queued_cmds;
443 	struct list_head	active_cmds;
444 
445 	u8			*command_block;
446 	dma_addr_t		command_block_dma;
447 
448 	unsigned int		data_dma_len;
449 
450 	/* The following are used to determine the cause of an IRQ. Upon every
451 	 * IRQ entry we synchronize these with the hardware registers.
452 	 */
453 	u8			sreg;
454 	u8			seqreg;
455 	u8			sreg2;
456 	u8			ireg;
457 
458 	u32			prev_hme_dmacsr;
459 	u8			prev_soff;
460 	u8			prev_stp;
461 	u8			prev_cfg3;
462 	u8			num_tags;
463 
464 	struct list_head	esp_cmd_pool;
465 
466 	struct esp_target_data	target[ESP_MAX_TARGET];
467 
468 	int			fifo_cnt;
469 	u8			fifo[16];
470 
471 	struct esp_event_ent	esp_event_log[ESP_EVENT_LOG_SZ];
472 	int			esp_event_cur;
473 
474 	u8			msg_out[ESP_MAX_MSG_SZ];
475 	int			msg_out_len;
476 
477 	u8			msg_in[ESP_MAX_MSG_SZ];
478 	int			msg_in_len;
479 
480 	u8			bursts;
481 	u8			config1;
482 	u8			config2;
483 	u8			config4;
484 
485 	u8			scsi_id;
486 	u32			scsi_id_mask;
487 
488 	enum esp_rev		rev;
489 
490 	u32			flags;
491 #define ESP_FLAG_DIFFERENTIAL	0x00000001
492 #define ESP_FLAG_RESETTING	0x00000002
493 #define ESP_FLAG_DOING_SLOWCMD	0x00000004
494 #define ESP_FLAG_WIDE_CAPABLE	0x00000008
495 #define ESP_FLAG_QUICKIRQ_CHECK	0x00000010
496 #define ESP_FLAG_DISABLE_SYNC	0x00000020
497 #define ESP_FLAG_USE_FIFO	0x00000040
498 
499 	u8			select_state;
500 #define ESP_SELECT_NONE		0x00 /* Not selecting */
501 #define ESP_SELECT_BASIC	0x01 /* Select w/o MSGOUT phase */
502 #define ESP_SELECT_MSGOUT	0x02 /* Select with MSGOUT */
503 
504 	/* When we are not selecting, we are expecting an event.  */
505 	u8			event;
506 #define ESP_EVENT_NONE		0x00
507 #define ESP_EVENT_CMD_START	0x01
508 #define ESP_EVENT_CMD_DONE	0x02
509 #define ESP_EVENT_DATA_IN	0x03
510 #define ESP_EVENT_DATA_OUT	0x04
511 #define ESP_EVENT_DATA_DONE	0x05
512 #define ESP_EVENT_MSGIN		0x06
513 #define ESP_EVENT_MSGIN_MORE	0x07
514 #define ESP_EVENT_MSGIN_DONE	0x08
515 #define ESP_EVENT_MSGOUT	0x09
516 #define ESP_EVENT_MSGOUT_DONE	0x0a
517 #define ESP_EVENT_STATUS	0x0b
518 #define ESP_EVENT_FREE_BUS	0x0c
519 #define ESP_EVENT_CHECK_PHASE	0x0d
520 #define ESP_EVENT_RESET		0x10
521 
522 	/* Probed in esp_get_clock_params() */
523 	u32			cfact;
524 	u32			cfreq;
525 	u32			ccycle;
526 	u32			ctick;
527 	u32			neg_defp;
528 	u32			sync_defp;
529 
530 	/* Computed in esp_reset_esp() */
531 	u32			max_period;
532 	u32			min_period;
533 	u32			radelay;
534 
535 	/* Slow command state.  */
536 	u8			*cmd_bytes_ptr;
537 	int			cmd_bytes_left;
538 
539 	struct completion	*eh_reset;
540 
541 	void			*dma;
542 	int			dmarev;
543 };
544 
545 /* A front-end driver for the ESP chip should do the following in
546  * it's device probe routine:
547  * 1) Allocate the host and private area using scsi_host_alloc()
548  *    with size 'sizeof(struct esp)'.  The first argument to
549  *    scsi_host_alloc() should be &scsi_esp_template.
550  * 2) Set host->max_id as appropriate.
551  * 3) Set esp->host to the scsi_host itself, and esp->dev
552  *    to the device object pointer.
553  * 4) Hook up esp->ops to the front-end implementation.
554  * 5) If the ESP chip supports wide transfers, set ESP_FLAG_WIDE_CAPABLE
555  *    in esp->flags.
556  * 6) Map the DMA and ESP chip registers.
557  * 7) DMA map the ESP command block, store the DMA address
558  *    in esp->command_block_dma.
559  * 8) Register the scsi_esp_intr() interrupt handler.
560  * 9) Probe for and provide the following chip properties:
561  *    esp->scsi_id (assign to esp->host->this_id too)
562  *    esp->scsi_id_mask
563  *    If ESP bus is differential, set ESP_FLAG_DIFFERENTIAL
564  *    esp->cfreq
565  *    DMA burst bit mask in esp->bursts, if necessary
566  * 10) Perform any actions necessary before the ESP device can
567  *     be programmed for the first time.  On some configs, for
568  *     example, the DMA engine has to be reset before ESP can
569  *     be programmed.
570  * 11) If necessary, call dev_set_drvdata() as needed.
571  * 12) Call scsi_esp_register() with prepared 'esp' structure
572  *     and a device pointer if possible.
573  * 13) Check scsi_esp_register() return value, release all resources
574  *     if an error was returned.
575  */
576 extern struct scsi_host_template scsi_esp_template;
577 extern int scsi_esp_register(struct esp *, struct device *);
578 
579 extern void scsi_esp_unregister(struct esp *);
580 extern irqreturn_t scsi_esp_intr(int, void *);
581 extern void scsi_esp_cmd(struct esp *, u8);
582 
583 #endif /* !(_ESP_SCSI_H) */
584