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1da177e4 LT |
1 | /* |
2 | * atari_scsi.c -- Device dependent functions for the Atari generic SCSI port | |
3 | * | |
4 | * Copyright 1994 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de> | |
5 | * | |
6 | * Loosely based on the work of Robert De Vries' team and added: | |
7 | * - working real DMA | |
8 | * - Falcon support (untested yet!) ++bjoern fixed and now it works | |
9 | * - lots of extensions and bug fixes. | |
10 | * | |
11 | * This file is subject to the terms and conditions of the GNU General Public | |
12 | * License. See the file COPYING in the main directory of this archive | |
13 | * for more details. | |
14 | * | |
15 | */ | |
16 | ||
17 | ||
18 | /**************************************************************************/ | |
19 | /* */ | |
20 | /* Notes for Falcon SCSI: */ | |
21 | /* ---------------------- */ | |
22 | /* */ | |
23 | /* Since the Falcon SCSI uses the ST-DMA chip, that is shared among */ | |
24 | /* several device drivers, locking and unlocking the access to this */ | |
25 | /* chip is required. But locking is not possible from an interrupt, */ | |
26 | /* since it puts the process to sleep if the lock is not available. */ | |
27 | /* This prevents "late" locking of the DMA chip, i.e. locking it just */ | |
28 | /* before using it, since in case of disconnection-reconnection */ | |
29 | /* commands, the DMA is started from the reselection interrupt. */ | |
30 | /* */ | |
31 | /* Two possible schemes for ST-DMA-locking would be: */ | |
32 | /* 1) The lock is taken for each command separately and disconnecting */ | |
33 | /* is forbidden (i.e. can_queue = 1). */ | |
34 | /* 2) The DMA chip is locked when the first command comes in and */ | |
35 | /* released when the last command is finished and all queues are */ | |
36 | /* empty. */ | |
37 | /* The first alternative would result in bad performance, since the */ | |
38 | /* interleaving of commands would not be used. The second is unfair to */ | |
39 | /* other drivers using the ST-DMA, because the queues will seldom be */ | |
40 | /* totally empty if there is a lot of disk traffic. */ | |
41 | /* */ | |
42 | /* For this reasons I decided to employ a more elaborate scheme: */ | |
43 | /* - First, we give up the lock every time we can (for fairness), this */ | |
44 | /* means every time a command finishes and there are no other commands */ | |
45 | /* on the disconnected queue. */ | |
46 | /* - If there are others waiting to lock the DMA chip, we stop */ | |
47 | /* issuing commands, i.e. moving them onto the issue queue. */ | |
48 | /* Because of that, the disconnected queue will run empty in a */ | |
49 | /* while. Instead we go to sleep on a 'fairness_queue'. */ | |
50 | /* - If the lock is released, all processes waiting on the fairness */ | |
51 | /* queue will be woken. The first of them tries to re-lock the DMA, */ | |
52 | /* the others wait for the first to finish this task. After that, */ | |
53 | /* they can all run on and do their commands... */ | |
54 | /* This sounds complicated (and it is it :-(), but it seems to be a */ | |
55 | /* good compromise between fairness and performance: As long as no one */ | |
56 | /* else wants to work with the ST-DMA chip, SCSI can go along as */ | |
57 | /* usual. If now someone else comes, this behaviour is changed to a */ | |
58 | /* "fairness mode": just already initiated commands are finished and */ | |
59 | /* then the lock is released. The other one waiting will probably win */ | |
60 | /* the race for locking the DMA, since it was waiting for longer. And */ | |
61 | /* after it has finished, SCSI can go ahead again. Finally: I hope I */ | |
62 | /* have not produced any deadlock possibilities! */ | |
63 | /* */ | |
64 | /**************************************************************************/ | |
65 | ||
66 | ||
1da177e4 | 67 | #include <linux/module.h> |
1da177e4 | 68 | #include <linux/types.h> |
1da177e4 | 69 | #include <linux/delay.h> |
1da177e4 | 70 | #include <linux/blkdev.h> |
1da177e4 LT |
71 | #include <linux/interrupt.h> |
72 | #include <linux/init.h> | |
73 | #include <linux/nvram.h> | |
74 | #include <linux/bitops.h> | |
eff9cf8d | 75 | #include <linux/wait.h> |
3ff228af | 76 | #include <linux/platform_device.h> |
1da177e4 LT |
77 | |
78 | #include <asm/setup.h> | |
79 | #include <asm/atarihw.h> | |
80 | #include <asm/atariints.h> | |
1da177e4 LT |
81 | #include <asm/atari_stdma.h> |
82 | #include <asm/atari_stram.h> | |
83 | #include <asm/io.h> | |
84 | ||
3ff228af FT |
85 | #include <scsi/scsi_host.h> |
86 | ||
4e705205 FT |
87 | /* Definitions for the core NCR5380 driver. */ |
88 | ||
89 | #define REAL_DMA | |
90 | #define SUPPORT_TAGS | |
91 | #define MAX_TAGS 32 | |
e3f463b0 | 92 | #define DMA_MIN_SIZE 32 |
4e705205 FT |
93 | |
94 | #define NCR5380_implementation_fields /* none */ | |
95 | ||
96 | #define NCR5380_read(reg) atari_scsi_reg_read(reg) | |
97 | #define NCR5380_write(reg, value) atari_scsi_reg_write(reg, value) | |
98 | ||
99 | #define NCR5380_queue_command atari_scsi_queue_command | |
100 | #define NCR5380_abort atari_scsi_abort | |
101 | #define NCR5380_show_info atari_scsi_show_info | |
102 | #define NCR5380_info atari_scsi_info | |
103 | ||
104 | #define NCR5380_dma_read_setup(instance, data, count) \ | |
105 | atari_scsi_dma_setup(instance, data, count, 0) | |
106 | #define NCR5380_dma_write_setup(instance, data, count) \ | |
107 | atari_scsi_dma_setup(instance, data, count, 1) | |
108 | #define NCR5380_dma_residual(instance) \ | |
109 | atari_scsi_dma_residual(instance) | |
110 | #define NCR5380_dma_xfer_len(instance, cmd, phase) \ | |
111 | atari_dma_xfer_len(cmd->SCp.this_residual, cmd, !((phase) & SR_IO)) | |
112 | ||
a53a21e4 | 113 | #define NCR5380_acquire_dma_irq(instance) falcon_get_lock(instance) |
e3c3da67 FT |
114 | #define NCR5380_release_dma_irq(instance) falcon_release_lock() |
115 | ||
3ff228af | 116 | #include "NCR5380.h" |
1da177e4 | 117 | |
4e705205 | 118 | |
1da177e4 LT |
119 | #define IS_A_TT() ATARIHW_PRESENT(TT_SCSI) |
120 | ||
121 | #define SCSI_DMA_WRITE_P(elt,val) \ | |
122 | do { \ | |
123 | unsigned long v = val; \ | |
124 | tt_scsi_dma.elt##_lo = v & 0xff; \ | |
125 | v >>= 8; \ | |
126 | tt_scsi_dma.elt##_lmd = v & 0xff; \ | |
127 | v >>= 8; \ | |
128 | tt_scsi_dma.elt##_hmd = v & 0xff; \ | |
129 | v >>= 8; \ | |
130 | tt_scsi_dma.elt##_hi = v & 0xff; \ | |
131 | } while(0) | |
132 | ||
133 | #define SCSI_DMA_READ_P(elt) \ | |
134 | (((((((unsigned long)tt_scsi_dma.elt##_hi << 8) | \ | |
135 | (unsigned long)tt_scsi_dma.elt##_hmd) << 8) | \ | |
136 | (unsigned long)tt_scsi_dma.elt##_lmd) << 8) | \ | |
137 | (unsigned long)tt_scsi_dma.elt##_lo) | |
138 | ||
139 | ||
140 | static inline void SCSI_DMA_SETADR(unsigned long adr) | |
141 | { | |
142 | st_dma.dma_lo = (unsigned char)adr; | |
143 | MFPDELAY(); | |
144 | adr >>= 8; | |
145 | st_dma.dma_md = (unsigned char)adr; | |
146 | MFPDELAY(); | |
147 | adr >>= 8; | |
148 | st_dma.dma_hi = (unsigned char)adr; | |
149 | MFPDELAY(); | |
150 | } | |
151 | ||
152 | static inline unsigned long SCSI_DMA_GETADR(void) | |
153 | { | |
154 | unsigned long adr; | |
155 | adr = st_dma.dma_lo; | |
156 | MFPDELAY(); | |
157 | adr |= (st_dma.dma_md & 0xff) << 8; | |
158 | MFPDELAY(); | |
159 | adr |= (st_dma.dma_hi & 0xff) << 16; | |
160 | MFPDELAY(); | |
161 | return adr; | |
162 | } | |
163 | ||
1da177e4 LT |
164 | #define HOSTDATA_DMALEN (((struct NCR5380_hostdata *) \ |
165 | (atari_scsi_host->hostdata))->dma_len) | |
166 | ||
167 | /* Time (in jiffies) to wait after a reset; the SCSI standard calls for 250ms, | |
168 | * we usually do 0.5s to be on the safe side. But Toshiba CD-ROMs once more | |
169 | * need ten times the standard value... */ | |
170 | #ifndef CONFIG_ATARI_SCSI_TOSHIBA_DELAY | |
171 | #define AFTER_RESET_DELAY (HZ/2) | |
172 | #else | |
173 | #define AFTER_RESET_DELAY (5*HZ/2) | |
174 | #endif | |
175 | ||
1da177e4 | 176 | #ifdef REAL_DMA |
c28bda25 | 177 | static void atari_scsi_fetch_restbytes(void); |
1da177e4 | 178 | #endif |
1da177e4 | 179 | |
c28bda25 RZ |
180 | static struct Scsi_Host *atari_scsi_host; |
181 | static unsigned char (*atari_scsi_reg_read)(unsigned char reg); | |
182 | static void (*atari_scsi_reg_write)(unsigned char reg, unsigned char value); | |
1da177e4 LT |
183 | |
184 | #ifdef REAL_DMA | |
185 | static unsigned long atari_dma_residual, atari_dma_startaddr; | |
186 | static short atari_dma_active; | |
187 | /* pointer to the dribble buffer */ | |
c28bda25 | 188 | static char *atari_dma_buffer; |
1da177e4 LT |
189 | /* precalculated physical address of the dribble buffer */ |
190 | static unsigned long atari_dma_phys_buffer; | |
191 | /* != 0 tells the Falcon int handler to copy data from the dribble buffer */ | |
192 | static char *atari_dma_orig_addr; | |
193 | /* size of the dribble buffer; 4k seems enough, since the Falcon cannot use | |
194 | * scatter-gather anyway, so most transfers are 1024 byte only. In the rare | |
195 | * cases where requests to physical contiguous buffers have been merged, this | |
196 | * request is <= 4k (one page). So I don't think we have to split transfers | |
197 | * just due to this buffer size... | |
198 | */ | |
199 | #define STRAM_BUFFER_SIZE (4096) | |
200 | /* mask for address bits that can't be used with the ST-DMA */ | |
201 | static unsigned long atari_dma_stram_mask; | |
202 | #define STRAM_ADDR(a) (((a) & atari_dma_stram_mask) == 0) | |
1da177e4 LT |
203 | #endif |
204 | ||
205 | static int setup_can_queue = -1; | |
8d3b33f6 | 206 | module_param(setup_can_queue, int, 0); |
1da177e4 | 207 | static int setup_cmd_per_lun = -1; |
8d3b33f6 | 208 | module_param(setup_cmd_per_lun, int, 0); |
1da177e4 | 209 | static int setup_sg_tablesize = -1; |
8d3b33f6 | 210 | module_param(setup_sg_tablesize, int, 0); |
1da177e4 LT |
211 | #ifdef SUPPORT_TAGS |
212 | static int setup_use_tagged_queuing = -1; | |
8d3b33f6 | 213 | module_param(setup_use_tagged_queuing, int, 0); |
1da177e4 LT |
214 | #endif |
215 | static int setup_hostid = -1; | |
8d3b33f6 | 216 | module_param(setup_hostid, int, 0); |
1da177e4 LT |
217 | |
218 | ||
1da177e4 LT |
219 | #if defined(REAL_DMA) |
220 | ||
c28bda25 | 221 | static int scsi_dma_is_ignored_buserr(unsigned char dma_stat) |
1da177e4 LT |
222 | { |
223 | int i; | |
c28bda25 | 224 | unsigned long addr = SCSI_DMA_READ_P(dma_addr), end_addr; |
1da177e4 LT |
225 | |
226 | if (dma_stat & 0x01) { | |
227 | ||
228 | /* A bus error happens when DMA-ing from the last page of a | |
229 | * physical memory chunk (DMA prefetch!), but that doesn't hurt. | |
230 | * Check for this case: | |
231 | */ | |
c28bda25 RZ |
232 | |
233 | for (i = 0; i < m68k_num_memory; ++i) { | |
234 | end_addr = m68k_memory[i].addr + m68k_memory[i].size; | |
1da177e4 | 235 | if (end_addr <= addr && addr <= end_addr + 4) |
c28bda25 | 236 | return 1; |
1da177e4 LT |
237 | } |
238 | } | |
c28bda25 | 239 | return 0; |
1da177e4 LT |
240 | } |
241 | ||
242 | ||
243 | #if 0 | |
244 | /* Dead code... wasn't called anyway :-) and causes some trouble, because at | |
245 | * end-of-DMA, both SCSI ints are triggered simultaneously, so the NCR int has | |
246 | * to clear the DMA int pending bit before it allows other level 6 interrupts. | |
247 | */ | |
c28bda25 | 248 | static void scsi_dma_buserr(int irq, void *dummy) |
1da177e4 | 249 | { |
c28bda25 | 250 | unsigned char dma_stat = tt_scsi_dma.dma_ctrl; |
1da177e4 LT |
251 | |
252 | /* Don't do anything if a NCR interrupt is pending. Probably it's just | |
253 | * masked... */ | |
c28bda25 | 254 | if (atari_irq_pending(IRQ_TT_MFP_SCSI)) |
1da177e4 | 255 | return; |
c28bda25 | 256 | |
1da177e4 LT |
257 | printk("Bad SCSI DMA interrupt! dma_addr=0x%08lx dma_stat=%02x dma_cnt=%08lx\n", |
258 | SCSI_DMA_READ_P(dma_addr), dma_stat, SCSI_DMA_READ_P(dma_cnt)); | |
259 | if (dma_stat & 0x80) { | |
c28bda25 RZ |
260 | if (!scsi_dma_is_ignored_buserr(dma_stat)) |
261 | printk("SCSI DMA bus error -- bad DMA programming!\n"); | |
262 | } else { | |
1da177e4 LT |
263 | /* Under normal circumstances we never should get to this point, |
264 | * since both interrupts are triggered simultaneously and the 5380 | |
265 | * int has higher priority. When this irq is handled, that DMA | |
266 | * interrupt is cleared. So a warning message is printed here. | |
267 | */ | |
c28bda25 | 268 | printk("SCSI DMA intr ?? -- this shouldn't happen!\n"); |
1da177e4 LT |
269 | } |
270 | } | |
271 | #endif | |
272 | ||
273 | #endif | |
274 | ||
275 | ||
c28bda25 | 276 | static irqreturn_t scsi_tt_intr(int irq, void *dummy) |
1da177e4 LT |
277 | { |
278 | #ifdef REAL_DMA | |
279 | int dma_stat; | |
280 | ||
281 | dma_stat = tt_scsi_dma.dma_ctrl; | |
282 | ||
d65e634a | 283 | dprintk(NDEBUG_INTR, "scsi%d: NCR5380 interrupt, DMA status = %02x\n", |
1da177e4 LT |
284 | atari_scsi_host->host_no, dma_stat & 0xff); |
285 | ||
286 | /* Look if it was the DMA that has interrupted: First possibility | |
287 | * is that a bus error occurred... | |
288 | */ | |
289 | if (dma_stat & 0x80) { | |
c28bda25 | 290 | if (!scsi_dma_is_ignored_buserr(dma_stat)) { |
1da177e4 LT |
291 | printk(KERN_ERR "SCSI DMA caused bus error near 0x%08lx\n", |
292 | SCSI_DMA_READ_P(dma_addr)); | |
293 | printk(KERN_CRIT "SCSI DMA bus error -- bad DMA programming!"); | |
294 | } | |
295 | } | |
296 | ||
297 | /* If the DMA is active but not finished, we have the case | |
298 | * that some other 5380 interrupt occurred within the DMA transfer. | |
299 | * This means we have residual bytes, if the desired end address | |
300 | * is not yet reached. Maybe we have to fetch some bytes from the | |
301 | * rest data register, too. The residual must be calculated from | |
302 | * the address pointer, not the counter register, because only the | |
303 | * addr reg counts bytes not yet written and pending in the rest | |
304 | * data reg! | |
305 | */ | |
306 | if ((dma_stat & 0x02) && !(dma_stat & 0x40)) { | |
c28bda25 | 307 | atari_dma_residual = HOSTDATA_DMALEN - (SCSI_DMA_READ_P(dma_addr) - atari_dma_startaddr); |
1da177e4 | 308 | |
d65e634a | 309 | dprintk(NDEBUG_DMA, "SCSI DMA: There are %ld residual bytes.\n", |
1da177e4 LT |
310 | atari_dma_residual); |
311 | ||
312 | if ((signed int)atari_dma_residual < 0) | |
313 | atari_dma_residual = 0; | |
314 | if ((dma_stat & 1) == 0) { | |
c28bda25 RZ |
315 | /* |
316 | * After read operations, we maybe have to | |
317 | * transport some rest bytes | |
318 | */ | |
1da177e4 | 319 | atari_scsi_fetch_restbytes(); |
c28bda25 RZ |
320 | } else { |
321 | /* | |
322 | * There seems to be a nasty bug in some SCSI-DMA/NCR | |
323 | * combinations: If a target disconnects while a write | |
324 | * operation is going on, the address register of the | |
325 | * DMA may be a few bytes farer than it actually read. | |
326 | * This is probably due to DMA prefetching and a delay | |
327 | * between DMA and NCR. Experiments showed that the | |
328 | * dma_addr is 9 bytes to high, but this could vary. | |
329 | * The problem is, that the residual is thus calculated | |
330 | * wrong and the next transfer will start behind where | |
331 | * it should. So we round up the residual to the next | |
332 | * multiple of a sector size, if it isn't already a | |
333 | * multiple and the originally expected transfer size | |
334 | * was. The latter condition is there to ensure that | |
335 | * the correction is taken only for "real" data | |
336 | * transfers and not for, e.g., the parameters of some | |
337 | * other command. These shouldn't disconnect anyway. | |
338 | */ | |
1da177e4 | 339 | if (atari_dma_residual & 0x1ff) { |
d65e634a | 340 | dprintk(NDEBUG_DMA, "SCSI DMA: DMA bug corrected, " |
1da177e4 LT |
341 | "difference %ld bytes\n", |
342 | 512 - (atari_dma_residual & 0x1ff)); | |
343 | atari_dma_residual = (atari_dma_residual + 511) & ~0x1ff; | |
344 | } | |
345 | } | |
346 | tt_scsi_dma.dma_ctrl = 0; | |
347 | } | |
348 | ||
349 | /* If the DMA is finished, fetch the rest bytes and turn it off */ | |
350 | if (dma_stat & 0x40) { | |
351 | atari_dma_residual = 0; | |
352 | if ((dma_stat & 1) == 0) | |
353 | atari_scsi_fetch_restbytes(); | |
354 | tt_scsi_dma.dma_ctrl = 0; | |
355 | } | |
356 | ||
357 | #endif /* REAL_DMA */ | |
c28bda25 | 358 | |
1e641664 | 359 | NCR5380_intr(irq, dummy); |
1da177e4 | 360 | |
1da177e4 LT |
361 | return IRQ_HANDLED; |
362 | } | |
363 | ||
364 | ||
c28bda25 | 365 | static irqreturn_t scsi_falcon_intr(int irq, void *dummy) |
1da177e4 LT |
366 | { |
367 | #ifdef REAL_DMA | |
368 | int dma_stat; | |
369 | ||
370 | /* Turn off DMA and select sector counter register before | |
371 | * accessing the status register (Atari recommendation!) | |
372 | */ | |
373 | st_dma.dma_mode_status = 0x90; | |
374 | dma_stat = st_dma.dma_mode_status; | |
375 | ||
376 | /* Bit 0 indicates some error in the DMA process... don't know | |
377 | * what happened exactly (no further docu). | |
378 | */ | |
379 | if (!(dma_stat & 0x01)) { | |
380 | /* DMA error */ | |
381 | printk(KERN_CRIT "SCSI DMA error near 0x%08lx!\n", SCSI_DMA_GETADR()); | |
382 | } | |
383 | ||
384 | /* If the DMA was active, but now bit 1 is not clear, it is some | |
385 | * other 5380 interrupt that finishes the DMA transfer. We have to | |
386 | * calculate the number of residual bytes and give a warning if | |
387 | * bytes are stuck in the ST-DMA fifo (there's no way to reach them!) | |
388 | */ | |
389 | if (atari_dma_active && (dma_stat & 0x02)) { | |
c28bda25 | 390 | unsigned long transferred; |
1da177e4 LT |
391 | |
392 | transferred = SCSI_DMA_GETADR() - atari_dma_startaddr; | |
393 | /* The ST-DMA address is incremented in 2-byte steps, but the | |
394 | * data are written only in 16-byte chunks. If the number of | |
395 | * transferred bytes is not divisible by 16, the remainder is | |
396 | * lost somewhere in outer space. | |
397 | */ | |
398 | if (transferred & 15) | |
399 | printk(KERN_ERR "SCSI DMA error: %ld bytes lost in " | |
400 | "ST-DMA fifo\n", transferred & 15); | |
401 | ||
402 | atari_dma_residual = HOSTDATA_DMALEN - transferred; | |
d65e634a | 403 | dprintk(NDEBUG_DMA, "SCSI DMA: There are %ld residual bytes.\n", |
1da177e4 | 404 | atari_dma_residual); |
c28bda25 | 405 | } else |
1da177e4 LT |
406 | atari_dma_residual = 0; |
407 | atari_dma_active = 0; | |
408 | ||
409 | if (atari_dma_orig_addr) { | |
410 | /* If the dribble buffer was used on a read operation, copy the DMA-ed | |
411 | * data to the original destination address. | |
412 | */ | |
413 | memcpy(atari_dma_orig_addr, phys_to_virt(atari_dma_startaddr), | |
414 | HOSTDATA_DMALEN - atari_dma_residual); | |
415 | atari_dma_orig_addr = NULL; | |
416 | } | |
417 | ||
418 | #endif /* REAL_DMA */ | |
419 | ||
1e641664 | 420 | NCR5380_intr(irq, dummy); |
1da177e4 LT |
421 | return IRQ_HANDLED; |
422 | } | |
423 | ||
424 | ||
425 | #ifdef REAL_DMA | |
c28bda25 | 426 | static void atari_scsi_fetch_restbytes(void) |
1da177e4 LT |
427 | { |
428 | int nr; | |
429 | char *src, *dst; | |
430 | unsigned long phys_dst; | |
431 | ||
432 | /* fetch rest bytes in the DMA register */ | |
433 | phys_dst = SCSI_DMA_READ_P(dma_addr); | |
434 | nr = phys_dst & 3; | |
435 | if (nr) { | |
436 | /* there are 'nr' bytes left for the last long address | |
437 | before the DMA pointer */ | |
438 | phys_dst ^= nr; | |
d65e634a | 439 | dprintk(NDEBUG_DMA, "SCSI DMA: there are %d rest bytes for phys addr 0x%08lx", |
1da177e4 LT |
440 | nr, phys_dst); |
441 | /* The content of the DMA pointer is a physical address! */ | |
442 | dst = phys_to_virt(phys_dst); | |
d65e634a | 443 | dprintk(NDEBUG_DMA, " = virt addr %p\n", dst); |
1da177e4 LT |
444 | for (src = (char *)&tt_scsi_dma.dma_restdata; nr != 0; --nr) |
445 | *dst++ = *src++; | |
446 | } | |
447 | } | |
448 | #endif /* REAL_DMA */ | |
449 | ||
450 | ||
1da177e4 | 451 | /* This function releases the lock on the DMA chip if there is no |
16b29e75 | 452 | * connected command and the disconnected queue is empty. |
1da177e4 LT |
453 | */ |
454 | ||
e3c3da67 | 455 | static void falcon_release_lock(void) |
1da177e4 | 456 | { |
c28bda25 RZ |
457 | if (IS_A_TT()) |
458 | return; | |
459 | ||
e3c3da67 | 460 | if (stdma_is_locked_by(scsi_falcon_intr)) |
1da177e4 | 461 | stdma_release(); |
1da177e4 LT |
462 | } |
463 | ||
464 | /* This function manages the locking of the ST-DMA. | |
465 | * If the DMA isn't locked already for SCSI, it tries to lock it by | |
466 | * calling stdma_lock(). But if the DMA is locked by the SCSI code and | |
467 | * there are other drivers waiting for the chip, we do not issue the | |
16b29e75 | 468 | * command immediately but tell the SCSI mid-layer to defer. |
1da177e4 LT |
469 | */ |
470 | ||
a53a21e4 | 471 | static int falcon_get_lock(struct Scsi_Host *instance) |
1da177e4 | 472 | { |
c28bda25 | 473 | if (IS_A_TT()) |
16b29e75 | 474 | return 1; |
1da177e4 | 475 | |
16b29e75 | 476 | if (in_interrupt()) |
a53a21e4 | 477 | return stdma_try_lock(scsi_falcon_intr, instance); |
1da177e4 | 478 | |
a53a21e4 | 479 | stdma_lock(scsi_falcon_intr, instance); |
16b29e75 | 480 | return 1; |
1da177e4 LT |
481 | } |
482 | ||
7b54e43a GU |
483 | #ifndef MODULE |
484 | static int __init atari_scsi_setup(char *str) | |
1da177e4 LT |
485 | { |
486 | /* Format of atascsi parameter is: | |
487 | * atascsi=<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags> | |
3ff228af | 488 | * Defaults depend on TT or Falcon, determined at run time. |
1da177e4 LT |
489 | * Negative values mean don't change. |
490 | */ | |
7b54e43a GU |
491 | int ints[6]; |
492 | ||
493 | get_options(str, ARRAY_SIZE(ints), ints); | |
c28bda25 | 494 | |
1da177e4 | 495 | if (ints[0] < 1) { |
c28bda25 | 496 | printk("atari_scsi_setup: no arguments!\n"); |
7b54e43a | 497 | return 0; |
1da177e4 | 498 | } |
3ff228af FT |
499 | if (ints[0] >= 1) |
500 | setup_can_queue = ints[1]; | |
501 | if (ints[0] >= 2) | |
502 | setup_cmd_per_lun = ints[2]; | |
503 | if (ints[0] >= 3) | |
504 | setup_sg_tablesize = ints[3]; | |
505 | if (ints[0] >= 4) | |
506 | setup_hostid = ints[4]; | |
1da177e4 | 507 | #ifdef SUPPORT_TAGS |
3ff228af FT |
508 | if (ints[0] >= 5) |
509 | setup_use_tagged_queuing = ints[5]; | |
1da177e4 | 510 | #endif |
7b54e43a GU |
511 | |
512 | return 1; | |
1da177e4 LT |
513 | } |
514 | ||
7b54e43a GU |
515 | __setup("atascsi=", atari_scsi_setup); |
516 | #endif /* !MODULE */ | |
517 | ||
c28bda25 | 518 | |
1da177e4 LT |
519 | #ifdef CONFIG_ATARI_SCSI_RESET_BOOT |
520 | static void __init atari_scsi_reset_boot(void) | |
521 | { | |
522 | unsigned long end; | |
c28bda25 | 523 | |
1da177e4 LT |
524 | /* |
525 | * Do a SCSI reset to clean up the bus during initialization. No messing | |
526 | * with the queues, interrupts, or locks necessary here. | |
527 | */ | |
528 | ||
c28bda25 | 529 | printk("Atari SCSI: resetting the SCSI bus..."); |
1da177e4 LT |
530 | |
531 | /* get in phase */ | |
c28bda25 RZ |
532 | NCR5380_write(TARGET_COMMAND_REG, |
533 | PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG))); | |
1da177e4 LT |
534 | |
535 | /* assert RST */ | |
c28bda25 | 536 | NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST); |
1da177e4 | 537 | /* The min. reset hold time is 25us, so 40us should be enough */ |
c28bda25 | 538 | udelay(50); |
1da177e4 | 539 | /* reset RST and interrupt */ |
c28bda25 RZ |
540 | NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
541 | NCR5380_read(RESET_PARITY_INTERRUPT_REG); | |
1da177e4 LT |
542 | |
543 | end = jiffies + AFTER_RESET_DELAY; | |
544 | while (time_before(jiffies, end)) | |
545 | barrier(); | |
546 | ||
c28bda25 | 547 | printk(" done\n"); |
1da177e4 LT |
548 | } |
549 | #endif | |
550 | ||
1da177e4 LT |
551 | #if defined(REAL_DMA) |
552 | ||
107b5d53 GU |
553 | static unsigned long atari_scsi_dma_setup(struct Scsi_Host *instance, |
554 | void *data, unsigned long count, | |
555 | int dir) | |
1da177e4 | 556 | { |
c28bda25 | 557 | unsigned long addr = virt_to_phys(data); |
1da177e4 | 558 | |
d65e634a | 559 | dprintk(NDEBUG_DMA, "scsi%d: setting up dma, data = %p, phys = %lx, count = %ld, " |
1da177e4 LT |
560 | "dir = %d\n", instance->host_no, data, addr, count, dir); |
561 | ||
562 | if (!IS_A_TT() && !STRAM_ADDR(addr)) { | |
563 | /* If we have a non-DMAable address on a Falcon, use the dribble | |
564 | * buffer; 'orig_addr' != 0 in the read case tells the interrupt | |
565 | * handler to copy data from the dribble buffer to the originally | |
566 | * wanted address. | |
567 | */ | |
568 | if (dir) | |
c28bda25 | 569 | memcpy(atari_dma_buffer, data, count); |
1da177e4 LT |
570 | else |
571 | atari_dma_orig_addr = data; | |
572 | addr = atari_dma_phys_buffer; | |
573 | } | |
c28bda25 | 574 | |
1da177e4 | 575 | atari_dma_startaddr = addr; /* Needed for calculating residual later. */ |
c28bda25 | 576 | |
1da177e4 LT |
577 | /* Cache cleanup stuff: On writes, push any dirty cache out before sending |
578 | * it to the peripheral. (Must be done before DMA setup, since at least | |
579 | * the ST-DMA begins to fill internal buffers right after setup. For | |
580 | * reads, invalidate any cache, may be altered after DMA without CPU | |
581 | * knowledge. | |
c28bda25 | 582 | * |
1da177e4 LT |
583 | * ++roman: For the Medusa, there's no need at all for that cache stuff, |
584 | * because the hardware does bus snooping (fine!). | |
585 | */ | |
c28bda25 | 586 | dma_cache_maintenance(addr, count, dir); |
1da177e4 LT |
587 | |
588 | if (count == 0) | |
589 | printk(KERN_NOTICE "SCSI warning: DMA programmed for 0 bytes !\n"); | |
590 | ||
591 | if (IS_A_TT()) { | |
592 | tt_scsi_dma.dma_ctrl = dir; | |
c28bda25 RZ |
593 | SCSI_DMA_WRITE_P(dma_addr, addr); |
594 | SCSI_DMA_WRITE_P(dma_cnt, count); | |
1da177e4 | 595 | tt_scsi_dma.dma_ctrl = dir | 2; |
c28bda25 RZ |
596 | } else { /* ! IS_A_TT */ |
597 | ||
1da177e4 | 598 | /* set address */ |
c28bda25 | 599 | SCSI_DMA_SETADR(addr); |
1da177e4 LT |
600 | |
601 | /* toggle direction bit to clear FIFO and set DMA direction */ | |
602 | dir <<= 8; | |
603 | st_dma.dma_mode_status = 0x90 | dir; | |
604 | st_dma.dma_mode_status = 0x90 | (dir ^ 0x100); | |
605 | st_dma.dma_mode_status = 0x90 | dir; | |
606 | udelay(40); | |
607 | /* On writes, round up the transfer length to the next multiple of 512 | |
608 | * (see also comment at atari_dma_xfer_len()). */ | |
609 | st_dma.fdc_acces_seccount = (count + (dir ? 511 : 0)) >> 9; | |
610 | udelay(40); | |
611 | st_dma.dma_mode_status = 0x10 | dir; | |
612 | udelay(40); | |
613 | /* need not restore value of dir, only boolean value is tested */ | |
614 | atari_dma_active = 1; | |
615 | } | |
616 | ||
c28bda25 | 617 | return count; |
1da177e4 LT |
618 | } |
619 | ||
620 | ||
c28bda25 | 621 | static long atari_scsi_dma_residual(struct Scsi_Host *instance) |
1da177e4 | 622 | { |
c28bda25 | 623 | return atari_dma_residual; |
1da177e4 LT |
624 | } |
625 | ||
626 | ||
627 | #define CMD_SURELY_BLOCK_MODE 0 | |
628 | #define CMD_SURELY_BYTE_MODE 1 | |
629 | #define CMD_MODE_UNKNOWN 2 | |
630 | ||
710ddd0d | 631 | static int falcon_classify_cmd(struct scsi_cmnd *cmd) |
1da177e4 LT |
632 | { |
633 | unsigned char opcode = cmd->cmnd[0]; | |
c28bda25 | 634 | |
1da177e4 | 635 | if (opcode == READ_DEFECT_DATA || opcode == READ_LONG || |
c28bda25 RZ |
636 | opcode == READ_BUFFER) |
637 | return CMD_SURELY_BYTE_MODE; | |
1da177e4 LT |
638 | else if (opcode == READ_6 || opcode == READ_10 || |
639 | opcode == 0xa8 /* READ_12 */ || opcode == READ_REVERSE || | |
640 | opcode == RECOVER_BUFFERED_DATA) { | |
641 | /* In case of a sequential-access target (tape), special care is | |
642 | * needed here: The transfer is block-mode only if the 'fixed' bit is | |
643 | * set! */ | |
644 | if (cmd->device->type == TYPE_TAPE && !(cmd->cmnd[1] & 1)) | |
c28bda25 | 645 | return CMD_SURELY_BYTE_MODE; |
1da177e4 | 646 | else |
c28bda25 RZ |
647 | return CMD_SURELY_BLOCK_MODE; |
648 | } else | |
649 | return CMD_MODE_UNKNOWN; | |
1da177e4 LT |
650 | } |
651 | ||
652 | ||
653 | /* This function calculates the number of bytes that can be transferred via | |
654 | * DMA. On the TT, this is arbitrary, but on the Falcon we have to use the | |
655 | * ST-DMA chip. There are only multiples of 512 bytes possible and max. | |
656 | * 255*512 bytes :-( This means also, that defining READ_OVERRUNS is not | |
657 | * possible on the Falcon, since that would require to program the DMA for | |
658 | * n*512 - atari_read_overrun bytes. But it seems that the Falcon doesn't have | |
659 | * the overrun problem, so this question is academic :-) | |
660 | */ | |
661 | ||
c28bda25 | 662 | static unsigned long atari_dma_xfer_len(unsigned long wanted_len, |
710ddd0d | 663 | struct scsi_cmnd *cmd, int write_flag) |
1da177e4 LT |
664 | { |
665 | unsigned long possible_len, limit; | |
29c8a246 | 666 | |
1da177e4 LT |
667 | if (IS_A_TT()) |
668 | /* TT SCSI DMA can transfer arbitrary #bytes */ | |
c28bda25 | 669 | return wanted_len; |
1da177e4 LT |
670 | |
671 | /* ST DMA chip is stupid -- only multiples of 512 bytes! (and max. | |
672 | * 255*512 bytes, but this should be enough) | |
673 | * | |
674 | * ++roman: Aaargl! Another Falcon-SCSI problem... There are some commands | |
675 | * that return a number of bytes which cannot be known beforehand. In this | |
676 | * case, the given transfer length is an "allocation length". Now it | |
677 | * can happen that this allocation length is a multiple of 512 bytes and | |
678 | * the DMA is used. But if not n*512 bytes really arrive, some input data | |
679 | * will be lost in the ST-DMA's FIFO :-( Thus, we have to distinguish | |
680 | * between commands that do block transfers and those that do byte | |
681 | * transfers. But this isn't easy... there are lots of vendor specific | |
682 | * commands, and the user can issue any command via the | |
683 | * SCSI_IOCTL_SEND_COMMAND. | |
684 | * | |
685 | * The solution: We classify SCSI commands in 1) surely block-mode cmd.s, | |
686 | * 2) surely byte-mode cmd.s and 3) cmd.s with unknown mode. In case 1) | |
687 | * and 3), the thing to do is obvious: allow any number of blocks via DMA | |
688 | * or none. In case 2), we apply some heuristic: Byte mode is assumed if | |
689 | * the transfer (allocation) length is < 1024, hoping that no cmd. not | |
690 | * explicitly known as byte mode have such big allocation lengths... | |
691 | * BTW, all the discussion above applies only to reads. DMA writes are | |
692 | * unproblematic anyways, since the targets aborts the transfer after | |
693 | * receiving a sufficient number of bytes. | |
694 | * | |
695 | * Another point: If the transfer is from/to an non-ST-RAM address, we | |
696 | * use the dribble buffer and thus can do only STRAM_BUFFER_SIZE bytes. | |
697 | */ | |
698 | ||
699 | if (write_flag) { | |
700 | /* Write operation can always use the DMA, but the transfer size must | |
701 | * be rounded up to the next multiple of 512 (atari_dma_setup() does | |
702 | * this). | |
703 | */ | |
704 | possible_len = wanted_len; | |
c28bda25 | 705 | } else { |
1da177e4 LT |
706 | /* Read operations: if the wanted transfer length is not a multiple of |
707 | * 512, we cannot use DMA, since the ST-DMA cannot split transfers | |
708 | * (no interrupt on DMA finished!) | |
709 | */ | |
710 | if (wanted_len & 0x1ff) | |
711 | possible_len = 0; | |
712 | else { | |
713 | /* Now classify the command (see above) and decide whether it is | |
714 | * allowed to do DMA at all */ | |
c28bda25 RZ |
715 | switch (falcon_classify_cmd(cmd)) { |
716 | case CMD_SURELY_BLOCK_MODE: | |
1da177e4 LT |
717 | possible_len = wanted_len; |
718 | break; | |
c28bda25 | 719 | case CMD_SURELY_BYTE_MODE: |
1da177e4 LT |
720 | possible_len = 0; /* DMA prohibited */ |
721 | break; | |
c28bda25 RZ |
722 | case CMD_MODE_UNKNOWN: |
723 | default: | |
1da177e4 LT |
724 | /* For unknown commands assume block transfers if the transfer |
725 | * size/allocation length is >= 1024 */ | |
726 | possible_len = (wanted_len < 1024) ? 0 : wanted_len; | |
727 | break; | |
728 | } | |
729 | } | |
730 | } | |
c28bda25 | 731 | |
1da177e4 | 732 | /* Last step: apply the hard limit on DMA transfers */ |
c28bda25 | 733 | limit = (atari_dma_buffer && !STRAM_ADDR(virt_to_phys(cmd->SCp.ptr))) ? |
1da177e4 LT |
734 | STRAM_BUFFER_SIZE : 255*512; |
735 | if (possible_len > limit) | |
736 | possible_len = limit; | |
737 | ||
738 | if (possible_len != wanted_len) | |
d65e634a | 739 | dprintk(NDEBUG_DMA, "Sorry, must cut DMA transfer size to %ld bytes " |
1da177e4 LT |
740 | "instead of %ld\n", possible_len, wanted_len); |
741 | ||
c28bda25 | 742 | return possible_len; |
1da177e4 LT |
743 | } |
744 | ||
745 | ||
746 | #endif /* REAL_DMA */ | |
747 | ||
748 | ||
749 | /* NCR5380 register access functions | |
750 | * | |
751 | * There are separate functions for TT and Falcon, because the access | |
752 | * methods are quite different. The calling macros NCR5380_read and | |
753 | * NCR5380_write call these functions via function pointers. | |
754 | */ | |
755 | ||
c28bda25 | 756 | static unsigned char atari_scsi_tt_reg_read(unsigned char reg) |
1da177e4 | 757 | { |
c28bda25 | 758 | return tt_scsi_regp[reg * 2]; |
1da177e4 LT |
759 | } |
760 | ||
c28bda25 | 761 | static void atari_scsi_tt_reg_write(unsigned char reg, unsigned char value) |
1da177e4 LT |
762 | { |
763 | tt_scsi_regp[reg * 2] = value; | |
764 | } | |
765 | ||
c28bda25 | 766 | static unsigned char atari_scsi_falcon_reg_read(unsigned char reg) |
1da177e4 LT |
767 | { |
768 | dma_wd.dma_mode_status= (u_short)(0x88 + reg); | |
c28bda25 | 769 | return (u_char)dma_wd.fdc_acces_seccount; |
1da177e4 LT |
770 | } |
771 | ||
c28bda25 | 772 | static void atari_scsi_falcon_reg_write(unsigned char reg, unsigned char value) |
1da177e4 LT |
773 | { |
774 | dma_wd.dma_mode_status = (u_short)(0x88 + reg); | |
775 | dma_wd.fdc_acces_seccount = (u_short)value; | |
776 | } | |
777 | ||
778 | ||
779 | #include "atari_NCR5380.c" | |
780 | ||
4d3d2a54 FT |
781 | static int atari_scsi_bus_reset(struct scsi_cmnd *cmd) |
782 | { | |
783 | int rv; | |
e3c3da67 FT |
784 | unsigned long flags; |
785 | ||
786 | local_irq_save(flags); | |
4d3d2a54 | 787 | |
4d3d2a54 | 788 | #ifdef REAL_DMA |
e3c3da67 FT |
789 | /* Abort a maybe active DMA transfer */ |
790 | if (IS_A_TT()) { | |
4d3d2a54 | 791 | tt_scsi_dma.dma_ctrl = 0; |
4d3d2a54 | 792 | } else { |
4d3d2a54 FT |
793 | st_dma.dma_mode_status = 0x90; |
794 | atari_dma_active = 0; | |
795 | atari_dma_orig_addr = NULL; | |
4d3d2a54 | 796 | } |
e3c3da67 | 797 | #endif |
4d3d2a54 FT |
798 | |
799 | rv = NCR5380_bus_reset(cmd); | |
800 | ||
e3c3da67 FT |
801 | /* The 5380 raises its IRQ line while _RST is active but the ST DMA |
802 | * "lock" has been released so this interrupt may end up handled by | |
803 | * floppy or IDE driver (if one of them holds the lock). The NCR5380 | |
804 | * interrupt flag has been cleared already. | |
805 | */ | |
4d3d2a54 | 806 | |
e3c3da67 | 807 | local_irq_restore(flags); |
4d3d2a54 FT |
808 | |
809 | return rv; | |
810 | } | |
811 | ||
3ff228af FT |
812 | #define DRV_MODULE_NAME "atari_scsi" |
813 | #define PFX DRV_MODULE_NAME ": " | |
814 | ||
815 | static struct scsi_host_template atari_scsi_template = { | |
816 | .module = THIS_MODULE, | |
817 | .proc_name = DRV_MODULE_NAME, | |
d89537e1 | 818 | .show_info = atari_scsi_show_info, |
1da177e4 | 819 | .name = "Atari native SCSI", |
1da177e4 LT |
820 | .info = atari_scsi_info, |
821 | .queuecommand = atari_scsi_queue_command, | |
822 | .eh_abort_handler = atari_scsi_abort, | |
823 | .eh_bus_reset_handler = atari_scsi_bus_reset, | |
3ff228af | 824 | .this_id = 7, |
1da177e4 LT |
825 | .use_clustering = DISABLE_CLUSTERING |
826 | }; | |
827 | ||
3ff228af FT |
828 | static int __init atari_scsi_probe(struct platform_device *pdev) |
829 | { | |
830 | struct Scsi_Host *instance; | |
831 | int error; | |
832 | struct resource *irq; | |
ef1081cb | 833 | int host_flags = 0; |
3ff228af FT |
834 | |
835 | irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); | |
836 | if (!irq) | |
837 | return -ENODEV; | |
838 | ||
839 | if (ATARIHW_PRESENT(TT_SCSI)) { | |
840 | atari_scsi_reg_read = atari_scsi_tt_reg_read; | |
841 | atari_scsi_reg_write = atari_scsi_tt_reg_write; | |
842 | } else { | |
843 | atari_scsi_reg_read = atari_scsi_falcon_reg_read; | |
844 | atari_scsi_reg_write = atari_scsi_falcon_reg_write; | |
845 | } | |
846 | ||
847 | /* The values for CMD_PER_LUN and CAN_QUEUE are somehow arbitrary. | |
848 | * Higher values should work, too; try it! | |
849 | * (But cmd_per_lun costs memory!) | |
850 | * | |
851 | * But there seems to be a bug somewhere that requires CAN_QUEUE to be | |
852 | * 2*CMD_PER_LUN. At least on a TT, no spurious timeouts seen since | |
853 | * changed CMD_PER_LUN... | |
854 | * | |
855 | * Note: The Falcon currently uses 8/1 setting due to unsolved problems | |
856 | * with cmd_per_lun != 1 | |
857 | */ | |
858 | if (ATARIHW_PRESENT(TT_SCSI)) { | |
859 | atari_scsi_template.can_queue = 16; | |
860 | atari_scsi_template.cmd_per_lun = 8; | |
861 | atari_scsi_template.sg_tablesize = SG_ALL; | |
862 | } else { | |
863 | atari_scsi_template.can_queue = 8; | |
864 | atari_scsi_template.cmd_per_lun = 1; | |
865 | atari_scsi_template.sg_tablesize = SG_NONE; | |
866 | } | |
867 | ||
868 | if (setup_can_queue > 0) | |
869 | atari_scsi_template.can_queue = setup_can_queue; | |
870 | ||
871 | if (setup_cmd_per_lun > 0) | |
872 | atari_scsi_template.cmd_per_lun = setup_cmd_per_lun; | |
873 | ||
874 | /* Leave sg_tablesize at 0 on a Falcon! */ | |
875 | if (ATARIHW_PRESENT(TT_SCSI) && setup_sg_tablesize >= 0) | |
876 | atari_scsi_template.sg_tablesize = setup_sg_tablesize; | |
877 | ||
878 | if (setup_hostid >= 0) { | |
879 | atari_scsi_template.this_id = setup_hostid & 7; | |
880 | } else { | |
881 | /* Test if a host id is set in the NVRam */ | |
882 | if (ATARIHW_PRESENT(TT_CLK) && nvram_check_checksum()) { | |
883 | unsigned char b = nvram_read_byte(14); | |
884 | ||
885 | /* Arbitration enabled? (for TOS) | |
886 | * If yes, use configured host ID | |
887 | */ | |
888 | if (b & 0x80) | |
889 | atari_scsi_template.this_id = b & 7; | |
890 | } | |
891 | } | |
892 | ||
3ff228af FT |
893 | |
894 | #ifdef REAL_DMA | |
895 | /* If running on a Falcon and if there's TT-Ram (i.e., more than one | |
896 | * memory block, since there's always ST-Ram in a Falcon), then | |
897 | * allocate a STRAM_BUFFER_SIZE byte dribble buffer for transfers | |
898 | * from/to alternative Ram. | |
899 | */ | |
900 | if (ATARIHW_PRESENT(ST_SCSI) && !ATARIHW_PRESENT(EXTD_DMA) && | |
901 | m68k_num_memory > 1) { | |
902 | atari_dma_buffer = atari_stram_alloc(STRAM_BUFFER_SIZE, "SCSI"); | |
903 | if (!atari_dma_buffer) { | |
904 | pr_err(PFX "can't allocate ST-RAM double buffer\n"); | |
905 | return -ENOMEM; | |
906 | } | |
907 | atari_dma_phys_buffer = atari_stram_to_phys(atari_dma_buffer); | |
908 | atari_dma_orig_addr = 0; | |
909 | } | |
910 | #endif | |
911 | ||
912 | instance = scsi_host_alloc(&atari_scsi_template, | |
913 | sizeof(struct NCR5380_hostdata)); | |
914 | if (!instance) { | |
915 | error = -ENOMEM; | |
916 | goto fail_alloc; | |
917 | } | |
918 | atari_scsi_host = instance; | |
919 | ||
920 | #ifdef CONFIG_ATARI_SCSI_RESET_BOOT | |
921 | atari_scsi_reset_boot(); | |
922 | #endif | |
923 | ||
924 | instance->irq = irq->start; | |
925 | ||
ef1081cb FT |
926 | host_flags |= IS_A_TT() ? 0 : FLAG_LATE_DMA_SETUP; |
927 | ||
ca513fc9 FT |
928 | #ifdef SUPPORT_TAGS |
929 | host_flags |= setup_use_tagged_queuing > 0 ? FLAG_TAGGED_QUEUING : 0; | |
930 | #endif | |
931 | ||
ef1081cb | 932 | NCR5380_init(instance, host_flags); |
3ff228af FT |
933 | |
934 | if (IS_A_TT()) { | |
935 | error = request_irq(instance->irq, scsi_tt_intr, 0, | |
936 | "NCR5380", instance); | |
937 | if (error) { | |
938 | pr_err(PFX "request irq %d failed, aborting\n", | |
939 | instance->irq); | |
940 | goto fail_irq; | |
941 | } | |
942 | tt_mfp.active_edge |= 0x80; /* SCSI int on L->H */ | |
943 | #ifdef REAL_DMA | |
944 | tt_scsi_dma.dma_ctrl = 0; | |
945 | atari_dma_residual = 0; | |
946 | ||
947 | /* While the read overruns (described by Drew Eckhardt in | |
948 | * NCR5380.c) never happened on TTs, they do in fact on the | |
949 | * Medusa (This was the cause why SCSI didn't work right for | |
950 | * so long there.) Since handling the overruns slows down | |
951 | * a bit, I turned the #ifdef's into a runtime condition. | |
952 | * | |
953 | * In principle it should be sufficient to do max. 1 byte with | |
954 | * PIO, but there is another problem on the Medusa with the DMA | |
ef1081cb | 955 | * rest data register. So read_overruns is currently set |
3ff228af FT |
956 | * to 4 to avoid having transfers that aren't a multiple of 4. |
957 | * If the rest data bug is fixed, this can be lowered to 1. | |
958 | */ | |
ef1081cb FT |
959 | if (MACH_IS_MEDUSA) { |
960 | struct NCR5380_hostdata *hostdata = | |
961 | shost_priv(instance); | |
962 | ||
963 | hostdata->read_overruns = 4; | |
964 | } | |
3ff228af FT |
965 | #endif |
966 | } else { | |
967 | /* Nothing to do for the interrupt: the ST-DMA is initialized | |
968 | * already. | |
969 | */ | |
970 | #ifdef REAL_DMA | |
971 | atari_dma_residual = 0; | |
972 | atari_dma_active = 0; | |
973 | atari_dma_stram_mask = (ATARIHW_PRESENT(EXTD_DMA) ? 0x00000000 | |
974 | : 0xff000000); | |
975 | #endif | |
976 | } | |
977 | ||
978 | error = scsi_add_host(instance, NULL); | |
979 | if (error) | |
980 | goto fail_host; | |
981 | ||
982 | platform_set_drvdata(pdev, instance); | |
983 | ||
984 | scsi_scan_host(instance); | |
985 | return 0; | |
986 | ||
987 | fail_host: | |
988 | if (IS_A_TT()) | |
989 | free_irq(instance->irq, instance); | |
990 | fail_irq: | |
991 | NCR5380_exit(instance); | |
992 | scsi_host_put(instance); | |
993 | fail_alloc: | |
994 | if (atari_dma_buffer) | |
995 | atari_stram_free(atari_dma_buffer); | |
996 | return error; | |
997 | } | |
998 | ||
999 | static int __exit atari_scsi_remove(struct platform_device *pdev) | |
1000 | { | |
1001 | struct Scsi_Host *instance = platform_get_drvdata(pdev); | |
1002 | ||
1003 | scsi_remove_host(instance); | |
1004 | if (IS_A_TT()) | |
1005 | free_irq(instance->irq, instance); | |
1006 | NCR5380_exit(instance); | |
1007 | scsi_host_put(instance); | |
1008 | if (atari_dma_buffer) | |
1009 | atari_stram_free(atari_dma_buffer); | |
1010 | return 0; | |
1011 | } | |
1012 | ||
1013 | static struct platform_driver atari_scsi_driver = { | |
1014 | .remove = __exit_p(atari_scsi_remove), | |
1015 | .driver = { | |
1016 | .name = DRV_MODULE_NAME, | |
3ff228af FT |
1017 | }, |
1018 | }; | |
1da177e4 | 1019 | |
3ff228af | 1020 | module_platform_driver_probe(atari_scsi_driver, atari_scsi_probe); |
1da177e4 | 1021 | |
3ff228af | 1022 | MODULE_ALIAS("platform:" DRV_MODULE_NAME); |
1da177e4 | 1023 | MODULE_LICENSE("GPL"); |