xref: /openbmc/linux/drivers/scsi/esp_scsi.h (revision 3b465a14)
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 */
82 #define ESP_CONFIG4_BBTE      0x01     /* Back-to-back transfers     (fsc)   */
83 #define ESP_CONGIG4_TEST      0x02     /* Transfer counter test mode (fsc)   */
84 #define ESP_CONFIG4_RADE      0x04     /* Active negation   (am53c974/fsc)   */
85 #define ESP_CONFIG4_RAE       0x08     /* Act. negation REQ/ACK (am53c974)   */
86 #define ESP_CONFIG4_PWD       0x20     /* Reduced power feature (am53c974)   */
87 #define ESP_CONFIG4_GE0       0x40     /* Glitch eater bit 0    (am53c974)   */
88 #define ESP_CONFIG4_GE1       0x80     /* Glitch eater bit 1    (am53c974)   */
89 
90 #define ESP_CONFIG_GE_12NS    (0)
91 #define ESP_CONFIG_GE_25NS    (ESP_CONFIG_GE1)
92 #define ESP_CONFIG_GE_35NS    (ESP_CONFIG_GE0)
93 #define ESP_CONFIG_GE_0NS     (ESP_CONFIG_GE0 | ESP_CONFIG_GE1)
94 
95 /* ESP command register read-write */
96 /* Group 1 commands:  These may be sent at any point in time to the ESP
97  *                    chip.  None of them can generate interrupts 'cept
98  *                    the "SCSI bus reset" command if you have not disabled
99  *                    SCSI reset interrupts in the config1 ESP register.
100  */
101 #define ESP_CMD_NULL          0x00     /* Null command, ie. a nop */
102 #define ESP_CMD_FLUSH         0x01     /* FIFO Flush */
103 #define ESP_CMD_RC            0x02     /* Chip reset */
104 #define ESP_CMD_RS            0x03     /* SCSI bus reset */
105 
106 /* Group 2 commands:  ESP must be an initiator and connected to a target
107  *                    for these commands to work.
108  */
109 #define ESP_CMD_TI            0x10     /* Transfer Information */
110 #define ESP_CMD_ICCSEQ        0x11     /* Initiator cmd complete sequence */
111 #define ESP_CMD_MOK           0x12     /* Message okie-dokie */
112 #define ESP_CMD_TPAD          0x18     /* Transfer Pad */
113 #define ESP_CMD_SATN          0x1a     /* Set ATN */
114 #define ESP_CMD_RATN          0x1b     /* De-assert ATN */
115 
116 /* Group 3 commands:  ESP must be in the MSGOUT or MSGIN state and be connected
117  *                    to a target as the initiator for these commands to work.
118  */
119 #define ESP_CMD_SMSG          0x20     /* Send message */
120 #define ESP_CMD_SSTAT         0x21     /* Send status */
121 #define ESP_CMD_SDATA         0x22     /* Send data */
122 #define ESP_CMD_DSEQ          0x23     /* Discontinue Sequence */
123 #define ESP_CMD_TSEQ          0x24     /* Terminate Sequence */
124 #define ESP_CMD_TCCSEQ        0x25     /* Target cmd cmplt sequence */
125 #define ESP_CMD_DCNCT         0x27     /* Disconnect */
126 #define ESP_CMD_RMSG          0x28     /* Receive Message */
127 #define ESP_CMD_RCMD          0x29     /* Receive Command */
128 #define ESP_CMD_RDATA         0x2a     /* Receive Data */
129 #define ESP_CMD_RCSEQ         0x2b     /* Receive cmd sequence */
130 
131 /* Group 4 commands:  The ESP must be in the disconnected state and must
132  *                    not be connected to any targets as initiator for
133  *                    these commands to work.
134  */
135 #define ESP_CMD_RSEL          0x40     /* Reselect */
136 #define ESP_CMD_SEL           0x41     /* Select w/o ATN */
137 #define ESP_CMD_SELA          0x42     /* Select w/ATN */
138 #define ESP_CMD_SELAS         0x43     /* Select w/ATN & STOP */
139 #define ESP_CMD_ESEL          0x44     /* Enable selection */
140 #define ESP_CMD_DSEL          0x45     /* Disable selections */
141 #define ESP_CMD_SA3           0x46     /* Select w/ATN3 */
142 #define ESP_CMD_RSEL3         0x47     /* Reselect3 */
143 
144 /* This bit enables the ESP's DMA on the SBus */
145 #define ESP_CMD_DMA           0x80     /* Do DMA? */
146 
147 /* ESP status register read-only */
148 #define ESP_STAT_PIO          0x01     /* IO phase bit */
149 #define ESP_STAT_PCD          0x02     /* CD phase bit */
150 #define ESP_STAT_PMSG         0x04     /* MSG phase bit */
151 #define ESP_STAT_PMASK        0x07     /* Mask of phase bits */
152 #define ESP_STAT_TDONE        0x08     /* Transfer Completed */
153 #define ESP_STAT_TCNT         0x10     /* Transfer Counter Is Zero */
154 #define ESP_STAT_PERR         0x20     /* Parity error */
155 #define ESP_STAT_SPAM         0x40     /* Real bad error */
156 /* This indicates the 'interrupt pending' condition on esp236, it is a reserved
157  * bit on other revs of the ESP.
158  */
159 #define ESP_STAT_INTR         0x80             /* Interrupt */
160 
161 /* The status register can be masked with ESP_STAT_PMASK and compared
162  * with the following values to determine the current phase the ESP
163  * (at least thinks it) is in.  For our purposes we also add our own
164  * software 'done' bit for our phase management engine.
165  */
166 #define ESP_DOP   (0)                                       /* Data Out  */
167 #define ESP_DIP   (ESP_STAT_PIO)                            /* Data In   */
168 #define ESP_CMDP  (ESP_STAT_PCD)                            /* Command   */
169 #define ESP_STATP (ESP_STAT_PCD|ESP_STAT_PIO)               /* Status    */
170 #define ESP_MOP   (ESP_STAT_PMSG|ESP_STAT_PCD)              /* Message Out */
171 #define ESP_MIP   (ESP_STAT_PMSG|ESP_STAT_PCD|ESP_STAT_PIO) /* Message In */
172 
173 /* HME only: status 2 register */
174 #define ESP_STAT2_SCHBIT      0x01 /* Upper bits 3-7 of sstep enabled */
175 #define ESP_STAT2_FFLAGS      0x02 /* The fifo flags are now latched */
176 #define ESP_STAT2_XCNT        0x04 /* The transfer counter is latched */
177 #define ESP_STAT2_CREGA       0x08 /* The command reg is active now */
178 #define ESP_STAT2_WIDE        0x10 /* Interface on this adapter is wide */
179 #define ESP_STAT2_F1BYTE      0x20 /* There is one byte at top of fifo */
180 #define ESP_STAT2_FMSB        0x40 /* Next byte in fifo is most significant */
181 #define ESP_STAT2_FEMPTY      0x80 /* FIFO is empty */
182 
183 /* ESP interrupt register read-only */
184 #define ESP_INTR_S            0x01     /* Select w/o ATN */
185 #define ESP_INTR_SATN         0x02     /* Select w/ATN */
186 #define ESP_INTR_RSEL         0x04     /* Reselected */
187 #define ESP_INTR_FDONE        0x08     /* Function done */
188 #define ESP_INTR_BSERV        0x10     /* Bus service */
189 #define ESP_INTR_DC           0x20     /* Disconnect */
190 #define ESP_INTR_IC           0x40     /* Illegal command given */
191 #define ESP_INTR_SR           0x80     /* SCSI bus reset detected */
192 
193 /* ESP sequence step register read-only */
194 #define ESP_STEP_VBITS        0x07     /* Valid bits */
195 #define ESP_STEP_ASEL         0x00     /* Selection&Arbitrate cmplt */
196 #define ESP_STEP_SID          0x01     /* One msg byte sent */
197 #define ESP_STEP_NCMD         0x02     /* Was not in command phase */
198 #define ESP_STEP_PPC          0x03     /* Early phase chg caused cmnd
199                                         * bytes to be lost
200                                         */
201 #define ESP_STEP_FINI4        0x04     /* Command was sent ok */
202 
203 /* Ho hum, some ESP's set the step register to this as well... */
204 #define ESP_STEP_FINI5        0x05
205 #define ESP_STEP_FINI6        0x06
206 #define ESP_STEP_FINI7        0x07
207 
208 /* ESP chip-test register read-write */
209 #define ESP_TEST_TARG         0x01     /* Target test mode */
210 #define ESP_TEST_INI          0x02     /* Initiator test mode */
211 #define ESP_TEST_TS           0x04     /* Tristate test mode */
212 
213 /* ESP unique ID register read-only, found on fas236+fas100a only */
214 #define ESP_UID_FAM           0xf8     /* ESP family bitmask */
215 
216 #define ESP_FAMILY(uid) (((uid) & ESP_UID_FAM) >> 3)
217 
218 /* Values for the ESP family bits */
219 #define ESP_UID_F100A         0x00     /* ESP FAS100A  */
220 #define ESP_UID_F236          0x02     /* ESP FAS236   */
221 #define ESP_UID_HME           0x0a     /* FAS HME      */
222 #define ESP_UID_FSC           0x14     /* NCR/Symbios Logic 53CF9x-2 */
223 
224 /* ESP fifo flags register read-only */
225 /* Note that the following implies a 16 byte FIFO on the ESP. */
226 #define ESP_FF_FBYTES         0x1f     /* Num bytes in FIFO */
227 #define ESP_FF_ONOTZERO       0x20     /* offset ctr not zero (esp100) */
228 #define ESP_FF_SSTEP          0xe0     /* Sequence step */
229 
230 /* ESP clock conversion factor register write-only */
231 #define ESP_CCF_F0            0x00     /* 35.01MHz - 40MHz */
232 #define ESP_CCF_NEVER         0x01     /* Set it to this and die */
233 #define ESP_CCF_F2            0x02     /* 10MHz */
234 #define ESP_CCF_F3            0x03     /* 10.01MHz - 15MHz */
235 #define ESP_CCF_F4            0x04     /* 15.01MHz - 20MHz */
236 #define ESP_CCF_F5            0x05     /* 20.01MHz - 25MHz */
237 #define ESP_CCF_F6            0x06     /* 25.01MHz - 30MHz */
238 #define ESP_CCF_F7            0x07     /* 30.01MHz - 35MHz */
239 
240 /* HME only... */
241 #define ESP_BUSID_RESELID     0x10
242 #define ESP_BUSID_CTR32BIT    0x40
243 
244 #define ESP_BUS_TIMEOUT        250     /* In milli-seconds */
245 #define ESP_TIMEO_CONST       8192
246 #define ESP_NEG_DEFP(mhz, cfact) \
247         ((ESP_BUS_TIMEOUT * ((mhz) / 1000)) / (8192 * (cfact)))
248 #define ESP_HZ_TO_CYCLE(hertz)  ((1000000000) / ((hertz) / 1000))
249 #define ESP_TICK(ccf, cycle)  ((7682 * (ccf) * (cycle) / 1000))
250 
251 /* For slow to medium speed input clock rates we shoot for 5mb/s, but for high
252  * input clock rates we try to do 10mb/s although I don't think a transfer can
253  * even run that fast with an ESP even with DMA2 scatter gather pipelining.
254  */
255 #define SYNC_DEFP_SLOW            0x32   /* 5mb/s  */
256 #define SYNC_DEFP_FAST            0x19   /* 10mb/s */
257 
258 struct esp_cmd_priv {
259 	int			num_sg;
260 	int			cur_residue;
261 	struct scatterlist	*prv_sg;
262 	struct scatterlist	*cur_sg;
263 	int			tot_residue;
264 };
265 
266 #define ESP_CMD_PRIV(cmd)	((struct esp_cmd_priv *)scsi_cmd_priv(cmd))
267 
268 /* NOTE: this enum is ordered based on chip features! */
269 enum esp_rev {
270 	ESP100,  /* NCR53C90 - very broken */
271 	ESP100A, /* NCR53C90A */
272 	ESP236,
273 	FAS236,
274 	PCSCSI,  /* AM53c974 */
275 	FSC,     /* NCR/Symbios Logic 53CF9x-2 */
276 	FAS100A,
277 	FAST,
278 	FASHME,
279 };
280 
281 struct esp_cmd_entry {
282 	struct list_head	list;
283 
284 	struct scsi_cmnd	*cmd;
285 
286 	unsigned int		saved_cur_residue;
287 	struct scatterlist	*saved_prv_sg;
288 	struct scatterlist	*saved_cur_sg;
289 	unsigned int		saved_tot_residue;
290 
291 	u8			flags;
292 #define ESP_CMD_FLAG_WRITE	0x01 /* DMA is a write */
293 #define ESP_CMD_FLAG_AUTOSENSE	0x04 /* Doing automatic REQUEST_SENSE */
294 #define ESP_CMD_FLAG_RESIDUAL	0x08 /* AM53c974 BLAST residual */
295 
296 	u8			tag[2];
297 	u8			orig_tag[2];
298 
299 	u8			status;
300 	u8			message;
301 
302 	unsigned char		*sense_ptr;
303 	unsigned char		*saved_sense_ptr;
304 	dma_addr_t		sense_dma;
305 
306 	struct completion	*eh_done;
307 };
308 
309 #define ESP_DEFAULT_TAGS	16
310 
311 #define ESP_MAX_TARGET		16
312 #define ESP_MAX_LUN		8
313 #define ESP_MAX_TAG		256
314 
315 struct esp_lun_data {
316 	struct esp_cmd_entry	*non_tagged_cmd;
317 	int			num_tagged;
318 	int			hold;
319 	struct esp_cmd_entry	*tagged_cmds[ESP_MAX_TAG];
320 };
321 
322 struct esp_target_data {
323 	/* These are the ESP_STP, ESP_SOFF, and ESP_CFG3 register values which
324 	 * match the currently negotiated settings for this target.  The SCSI
325 	 * protocol values are maintained in spi_{offset,period,wide}(starget).
326 	 */
327 	u8			esp_period;
328 	u8			esp_offset;
329 	u8			esp_config3;
330 
331 	u8			flags;
332 #define ESP_TGT_WIDE		0x01
333 #define ESP_TGT_DISCONNECT	0x02
334 #define ESP_TGT_NEGO_WIDE	0x04
335 #define ESP_TGT_NEGO_SYNC	0x08
336 #define ESP_TGT_CHECK_NEGO	0x40
337 #define ESP_TGT_BROKEN		0x80
338 
339 	/* When ESP_TGT_CHECK_NEGO is set, on the next scsi command to this
340 	 * device we will try to negotiate the following parameters.
341 	 */
342 	u8			nego_goal_period;
343 	u8			nego_goal_offset;
344 	u8			nego_goal_width;
345 	u8			nego_goal_tags;
346 
347 	struct scsi_target	*starget;
348 };
349 
350 struct esp_event_ent {
351 	u8			type;
352 #define ESP_EVENT_TYPE_EVENT	0x01
353 #define ESP_EVENT_TYPE_CMD	0x02
354 	u8			val;
355 
356 	u8			sreg;
357 	u8			seqreg;
358 	u8			sreg2;
359 	u8			ireg;
360 	u8			select_state;
361 	u8			event;
362 	u8			__pad;
363 };
364 
365 struct esp;
366 struct esp_driver_ops {
367 	/* Read and write the ESP 8-bit registers.  On some
368 	 * applications of the ESP chip the registers are at 4-byte
369 	 * instead of 1-byte intervals.
370 	 */
371 	void (*esp_write8)(struct esp *esp, u8 val, unsigned long reg);
372 	u8 (*esp_read8)(struct esp *esp, unsigned long reg);
373 
374 	/* Return non-zero if there is an IRQ pending.  Usually this
375 	 * status bit lives in the DMA controller sitting in front of
376 	 * the ESP.  This has to be accurate or else the ESP interrupt
377 	 * handler will not run.
378 	 */
379 	int (*irq_pending)(struct esp *esp);
380 
381 	/* Return the maximum allowable size of a DMA transfer for a
382 	 * given buffer.
383 	 */
384 	u32 (*dma_length_limit)(struct esp *esp, u32 dma_addr,
385 				u32 dma_len);
386 
387 	/* Reset the DMA engine entirely.  On return, ESP interrupts
388 	 * should be enabled.  Often the interrupt enabling is
389 	 * controlled in the DMA engine.
390 	 */
391 	void (*reset_dma)(struct esp *esp);
392 
393 	/* Drain any pending DMA in the DMA engine after a transfer.
394 	 * This is for writes to memory.
395 	 */
396 	void (*dma_drain)(struct esp *esp);
397 
398 	/* Invalidate the DMA engine after a DMA transfer.  */
399 	void (*dma_invalidate)(struct esp *esp);
400 
401 	/* Setup an ESP command that will use a DMA transfer.
402 	 * The 'esp_count' specifies what transfer length should be
403 	 * programmed into the ESP transfer counter registers, whereas
404 	 * the 'dma_count' is the length that should be programmed into
405 	 * the DMA controller.  Usually they are the same.  If 'write'
406 	 * is non-zero, this transfer is a write into memory.  'cmd'
407 	 * holds the ESP command that should be issued by calling
408 	 * scsi_esp_cmd() at the appropriate time while programming
409 	 * the DMA hardware.
410 	 */
411 	void (*send_dma_cmd)(struct esp *esp, u32 dma_addr, u32 esp_count,
412 			     u32 dma_count, int write, u8 cmd);
413 
414 	/* Return non-zero if the DMA engine is reporting an error
415 	 * currently.
416 	 */
417 	int (*dma_error)(struct esp *esp);
418 };
419 
420 #define ESP_MAX_MSG_SZ		8
421 #define ESP_EVENT_LOG_SZ	32
422 
423 #define ESP_QUICKIRQ_LIMIT	100
424 #define ESP_RESELECT_TAG_LIMIT	2500
425 
426 struct esp {
427 	void __iomem		*regs;
428 	void __iomem		*dma_regs;
429 
430 	const struct esp_driver_ops *ops;
431 
432 	struct Scsi_Host	*host;
433 	struct device		*dev;
434 
435 	struct esp_cmd_entry	*active_cmd;
436 
437 	struct list_head	queued_cmds;
438 	struct list_head	active_cmds;
439 
440 	u8			*command_block;
441 	dma_addr_t		command_block_dma;
442 
443 	unsigned int		data_dma_len;
444 
445 	/* The following are used to determine the cause of an IRQ. Upon every
446 	 * IRQ entry we synchronize these with the hardware registers.
447 	 */
448 	u8			sreg;
449 	u8			seqreg;
450 	u8			sreg2;
451 	u8			ireg;
452 
453 	u32			prev_hme_dmacsr;
454 	u8			prev_soff;
455 	u8			prev_stp;
456 	u8			prev_cfg3;
457 	u8			num_tags;
458 
459 	struct list_head	esp_cmd_pool;
460 
461 	struct esp_target_data	target[ESP_MAX_TARGET];
462 
463 	int			fifo_cnt;
464 	u8			fifo[16];
465 
466 	struct esp_event_ent	esp_event_log[ESP_EVENT_LOG_SZ];
467 	int			esp_event_cur;
468 
469 	u8			msg_out[ESP_MAX_MSG_SZ];
470 	int			msg_out_len;
471 
472 	u8			msg_in[ESP_MAX_MSG_SZ];
473 	int			msg_in_len;
474 
475 	u8			bursts;
476 	u8			config1;
477 	u8			config2;
478 	u8			config4;
479 
480 	u8			scsi_id;
481 	u32			scsi_id_mask;
482 
483 	enum esp_rev		rev;
484 
485 	u32			flags;
486 #define ESP_FLAG_DIFFERENTIAL	0x00000001
487 #define ESP_FLAG_RESETTING	0x00000002
488 #define ESP_FLAG_WIDE_CAPABLE	0x00000008
489 #define ESP_FLAG_QUICKIRQ_CHECK	0x00000010
490 #define ESP_FLAG_DISABLE_SYNC	0x00000020
491 #define ESP_FLAG_USE_FIFO	0x00000040
492 #define ESP_FLAG_NO_DMA_MAP	0x00000080
493 
494 	u8			select_state;
495 #define ESP_SELECT_NONE		0x00 /* Not selecting */
496 #define ESP_SELECT_BASIC	0x01 /* Select w/o MSGOUT phase */
497 #define ESP_SELECT_MSGOUT	0x02 /* Select with MSGOUT */
498 
499 	/* When we are not selecting, we are expecting an event.  */
500 	u8			event;
501 #define ESP_EVENT_NONE		0x00
502 #define ESP_EVENT_CMD_START	0x01
503 #define ESP_EVENT_CMD_DONE	0x02
504 #define ESP_EVENT_DATA_IN	0x03
505 #define ESP_EVENT_DATA_OUT	0x04
506 #define ESP_EVENT_DATA_DONE	0x05
507 #define ESP_EVENT_MSGIN		0x06
508 #define ESP_EVENT_MSGIN_MORE	0x07
509 #define ESP_EVENT_MSGIN_DONE	0x08
510 #define ESP_EVENT_MSGOUT	0x09
511 #define ESP_EVENT_MSGOUT_DONE	0x0a
512 #define ESP_EVENT_STATUS	0x0b
513 #define ESP_EVENT_FREE_BUS	0x0c
514 #define ESP_EVENT_CHECK_PHASE	0x0d
515 #define ESP_EVENT_RESET		0x10
516 
517 	/* Probed in esp_get_clock_params() */
518 	u32			cfact;
519 	u32			cfreq;
520 	u32			ccycle;
521 	u32			ctick;
522 	u32			neg_defp;
523 	u32			sync_defp;
524 
525 	/* Computed in esp_reset_esp() */
526 	u32			max_period;
527 	u32			min_period;
528 	u32			radelay;
529 
530 	/* ESP_CMD_SELAS command state */
531 	u8			*cmd_bytes_ptr;
532 	int			cmd_bytes_left;
533 
534 	struct completion	*eh_reset;
535 
536 	void			*dma;
537 	int			dmarev;
538 
539 	/* These are used by esp_send_pio_cmd() */
540 	u8 __iomem		*fifo_reg;
541 	int			send_cmd_error;
542 	u32			send_cmd_residual;
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  * 13) Check scsi_esp_register() return value, release all resources
573  *     if an error was returned.
574  */
575 extern const struct scsi_host_template scsi_esp_template;
576 extern int scsi_esp_register(struct esp *);
577 
578 extern void scsi_esp_unregister(struct esp *);
579 extern irqreturn_t scsi_esp_intr(int, void *);
580 extern void scsi_esp_cmd(struct esp *, u8);
581 
582 extern void esp_send_pio_cmd(struct esp *esp, u32 dma_addr, u32 esp_count,
583 			     u32 dma_count, int write, u8 cmd);
584 
585 #endif /* !(_ESP_SCSI_H) */
586