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arxescsi.c
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1 /*
2  * linux/drivers/scsi/arm/arxescsi.c
3  *
4  * Copyright (C) 1997-2000 Russell King, Stefan Hanske
5  *
6  * This driver is based on experimentation. Hence, it may have made
7  * assumptions about the particular card that I have available, and
8  * may not be reliable!
9  *
10  * Changelog:
11  * 30-08-1997 RMK 0.0.0 Created, READONLY version as cumana_2.c
12  * 22-01-1998 RMK 0.0.1 Updated to 2.1.80
13  * 15-04-1998 RMK 0.0.1 Only do PIO if FAS216 will allow it.
14  * 11-06-1998 SH 0.0.2 Changed to support ARXE 16-bit SCSI card
15  * enabled writing
16  * 01-01-2000 SH 0.1.0 Added *real* pseudo dma writing
17  * (arxescsi_pseudo_dma_write)
18  * 02-04-2000 RMK 0.1.1 Updated for new error handling code.
19  * 22-10-2000 SH Updated for new registering scheme.
20  */
21 #include <linux/module.h>
22 #include <linux/blkdev.h>
23 #include <linux/kernel.h>
24 #include <linux/string.h>
25 #include <linux/ioport.h>
26 #include <linux/proc_fs.h>
27 #include <linux/unistd.h>
28 #include <linux/stat.h>
29 #include <linux/delay.h>
30 #include <linux/init.h>
31 #include <linux/interrupt.h>
32 
33 #include <asm/dma.h>
34 #include <asm/io.h>
35 #include <asm/ecard.h>
36 
37 #include "../scsi.h"
38 #include <scsi/scsi_host.h>
39 #include "fas216.h"
40 
41 struct arxescsi_info {
42  FAS216_Info info;
43  struct expansion_card *ec;
44  void __iomem *base;
45 };
46 
47 #define DMADATA_OFFSET (0x200)
48 
49 #define DMASTAT_OFFSET (0x600)
50 #define DMASTAT_DRQ (1 << 0)
51 
52 #define CSTATUS_IRQ (1 << 0)
53 
54 #define VERSION "1.10 (23/01/2003 2.5.57)"
55 
56 /*
57  * Function: int arxescsi_dma_setup(host, SCpnt, direction, min_type)
58  * Purpose : initialises DMA/PIO
59  * Params : host - host
60  * SCpnt - command
61  * direction - DMA on to/off of card
62  * min_type - minimum DMA support that we must have for this transfer
63  * Returns : 0 if we should not set CMD_WITHDMA for transfer info command
64  */
65 static fasdmatype_t
66 arxescsi_dma_setup(struct Scsi_Host *host, struct scsi_pointer *SCp,
67  fasdmadir_t direction, fasdmatype_t min_type)
68 {
69  /*
70  * We don't do real DMA
71  */
72  return fasdma_pseudo;
73 }
74 
75 static void arxescsi_pseudo_dma_write(unsigned char *addr, void __iomem *base)
76 {
77  __asm__ __volatile__(
78  " stmdb sp!, {r0-r12}\n"
79  " mov r3, %0\n"
80  " mov r1, %1\n"
81  " add r2, r1, #512\n"
82  " mov r4, #256\n"
83  ".loop_1: ldmia r3!, {r6, r8, r10, r12}\n"
84  " mov r5, r6, lsl #16\n"
85  " mov r7, r8, lsl #16\n"
86  ".loop_2: ldrb r0, [r1, #1536]\n"
87  " tst r0, #1\n"
88  " beq .loop_2\n"
89  " stmia r2, {r5-r8}\n\t"
90  " mov r9, r10, lsl #16\n"
91  " mov r11, r12, lsl #16\n"
92  ".loop_3: ldrb r0, [r1, #1536]\n"
93  " tst r0, #1\n"
94  " beq .loop_3\n"
95  " stmia r2, {r9-r12}\n"
96  " subs r4, r4, #16\n"
97  " bne .loop_1\n"
98  " ldmia sp!, {r0-r12}\n"
99  :
100  : "r" (addr), "r" (base));
101 }
102 
103 /*
104  * Function: int arxescsi_dma_pseudo(host, SCpnt, direction, transfer)
105  * Purpose : handles pseudo DMA
106  * Params : host - host
107  * SCpnt - command
108  * direction - DMA on to/off of card
109  * transfer - minimum number of bytes we expect to transfer
110  */
111 static void
112 arxescsi_dma_pseudo(struct Scsi_Host *host, struct scsi_pointer *SCp,
113  fasdmadir_t direction, int transfer)
114 {
115  struct arxescsi_info *info = (struct arxescsi_info *)host->hostdata;
116  unsigned int length, error = 0;
117  void __iomem *base = info->info.scsi.io_base;
118  unsigned char *addr;
119 
120  length = SCp->this_residual;
121  addr = SCp->ptr;
122 
123  if (direction == DMA_OUT) {
124  unsigned int word;
125  while (length > 256) {
126  if (readb(base + 0x80) & STAT_INT) {
127  error = 1;
128  break;
129  }
130  arxescsi_pseudo_dma_write(addr, base);
131  addr += 256;
132  length -= 256;
133  }
134 
135  if (!error)
136  while (length > 0) {
137  if (readb(base + 0x80) & STAT_INT)
138  break;
139 
140  if (!(readb(base + DMASTAT_OFFSET) & DMASTAT_DRQ))
141  continue;
142 
143  word = *addr | *(addr + 1) << 8;
144 
145  writew(word, base + DMADATA_OFFSET);
146  if (length > 1) {
147  addr += 2;
148  length -= 2;
149  } else {
150  addr += 1;
151  length -= 1;
152  }
153  }
154  }
155  else {
156  if (transfer && (transfer & 255)) {
157  while (length >= 256) {
158  if (readb(base + 0x80) & STAT_INT) {
159  error = 1;
160  break;
161  }
162 
163  if (!(readb(base + DMASTAT_OFFSET) & DMASTAT_DRQ))
164  continue;
165 
166  readsw(base + DMADATA_OFFSET, addr, 256 >> 1);
167  addr += 256;
168  length -= 256;
169  }
170  }
171 
172  if (!(error))
173  while (length > 0) {
174  unsigned long word;
175 
176  if (readb(base + 0x80) & STAT_INT)
177  break;
178 
179  if (!(readb(base + DMASTAT_OFFSET) & DMASTAT_DRQ))
180  continue;
181 
182  word = readw(base + DMADATA_OFFSET);
183  *addr++ = word;
184  if (--length > 0) {
185  *addr++ = word >> 8;
186  length --;
187  }
188  }
189  }
190 }
191 
192 /*
193  * Function: int arxescsi_dma_stop(host, SCpnt)
194  * Purpose : stops DMA/PIO
195  * Params : host - host
196  * SCpnt - command
197  */
198 static void arxescsi_dma_stop(struct Scsi_Host *host, struct scsi_pointer *SCp)
199 {
200  /*
201  * no DMA to stop
202  */
203 }
204 
205 /*
206  * Function: const char *arxescsi_info(struct Scsi_Host * host)
207  * Purpose : returns a descriptive string about this interface,
208  * Params : host - driver host structure to return info for.
209  * Returns : pointer to a static buffer containing null terminated string.
210  */
211 static const char *arxescsi_info(struct Scsi_Host *host)
212 {
213  struct arxescsi_info *info = (struct arxescsi_info *)host->hostdata;
214  static char string[150];
215 
216  sprintf(string, "%s (%s) in slot %d v%s",
217  host->hostt->name, info->info.scsi.type, info->ec->slot_no,
218  VERSION);
219 
220  return string;
221 }
222 
223 /*
224  * Function: int arxescsi_proc_info(char *buffer, char **start, off_t offset,
225  * int length, int host_no, int inout)
226  * Purpose : Return information about the driver to a user process accessing
227  * the /proc filesystem.
228  * Params : buffer - a buffer to write information to
229  * start - a pointer into this buffer set by this routine to the start
230  * of the required information.
231  * offset - offset into information that we have read up to.
232  * length - length of buffer
233  * host_no - host number to return information for
234  * inout - 0 for reading, 1 for writing.
235  * Returns : length of data written to buffer.
236  */
237 static int
238 arxescsi_proc_info(struct Scsi_Host *host, char *buffer, char **start, off_t offset, int length,
239  int inout)
240 {
241  struct arxescsi_info *info;
242  char *p = buffer;
243  int pos;
244 
245  info = (struct arxescsi_info *)host->hostdata;
246  if (inout == 1)
247  return -EINVAL;
248 
249  p += sprintf(p, "ARXE 16-bit SCSI driver v%s\n", VERSION);
250  p += fas216_print_host(&info->info, p);
251  p += fas216_print_stats(&info->info, p);
252  p += fas216_print_devices(&info->info, p);
253 
254  *start = buffer + offset;
255  pos = p - buffer - offset;
256  if (pos > length)
257  pos = length;
258 
259  return pos;
260 }
261 
262 static struct scsi_host_template arxescsi_template = {
263  .proc_info = arxescsi_proc_info,
264  .name = "ARXE SCSI card",
265  .info = arxescsi_info,
266  .queuecommand = fas216_noqueue_command,
267  .eh_host_reset_handler = fas216_eh_host_reset,
268  .eh_bus_reset_handler = fas216_eh_bus_reset,
269  .eh_device_reset_handler = fas216_eh_device_reset,
270  .eh_abort_handler = fas216_eh_abort,
271  .can_queue = 0,
272  .this_id = 7,
273  .sg_tablesize = SG_ALL,
274  .cmd_per_lun = 1,
275  .use_clustering = DISABLE_CLUSTERING,
276  .proc_name = "arxescsi",
277 };
278 
279 static int __devinit
280 arxescsi_probe(struct expansion_card *ec, const struct ecard_id *id)
281 {
282  struct Scsi_Host *host;
283  struct arxescsi_info *info;
284  void __iomem *base;
285  int ret;
286 
287  ret = ecard_request_resources(ec);
288  if (ret)
289  goto out;
290 
291  base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
292  if (!base) {
293  ret = -ENOMEM;
294  goto out_region;
295  }
296 
297  host = scsi_host_alloc(&arxescsi_template, sizeof(struct arxescsi_info));
298  if (!host) {
299  ret = -ENOMEM;
300  goto out_region;
301  }
302 
303  info = (struct arxescsi_info *)host->hostdata;
304  info->ec = ec;
305  info->base = base;
306 
307  info->info.scsi.io_base = base + 0x2000;
308  info->info.scsi.irq = 0;
309  info->info.scsi.dma = NO_DMA;
310  info->info.scsi.io_shift = 5;
311  info->info.ifcfg.clockrate = 24; /* MHz */
312  info->info.ifcfg.select_timeout = 255;
313  info->info.ifcfg.asyncperiod = 200; /* ns */
314  info->info.ifcfg.sync_max_depth = 0;
315  info->info.ifcfg.cntl3 = CNTL3_FASTSCSI | CNTL3_FASTCLK;
316  info->info.ifcfg.disconnect_ok = 0;
317  info->info.ifcfg.wide_max_size = 0;
318  info->info.ifcfg.capabilities = FASCAP_PSEUDODMA;
319  info->info.dma.setup = arxescsi_dma_setup;
320  info->info.dma.pseudo = arxescsi_dma_pseudo;
321  info->info.dma.stop = arxescsi_dma_stop;
322 
323  ec->irqaddr = base;
324  ec->irqmask = CSTATUS_IRQ;
325 
326  ret = fas216_init(host);
327  if (ret)
328  goto out_unregister;
329 
330  ret = fas216_add(host, &ec->dev);
331  if (ret == 0)
332  goto out;
333 
334  fas216_release(host);
335  out_unregister:
336  scsi_host_put(host);
337  out_region:
338  ecard_release_resources(ec);
339  out:
340  return ret;
341 }
342 
343 static void __devexit arxescsi_remove(struct expansion_card *ec)
344 {
345  struct Scsi_Host *host = ecard_get_drvdata(ec);
346 
347  ecard_set_drvdata(ec, NULL);
348  fas216_remove(host);
349 
350  fas216_release(host);
351  scsi_host_put(host);
352  ecard_release_resources(ec);
353 }
354 
355 static const struct ecard_id arxescsi_cids[] = {
356  { MANU_ARXE, PROD_ARXE_SCSI },
357  { 0xffff, 0xffff },
358 };
359 
360 static struct ecard_driver arxescsi_driver = {
361  .probe = arxescsi_probe,
362  .remove = __devexit_p(arxescsi_remove),
363  .id_table = arxescsi_cids,
364  .drv = {
365  .name = "arxescsi",
366  },
367 };
368 
369 static int __init init_arxe_scsi_driver(void)
370 {
371  return ecard_register_driver(&arxescsi_driver);
372 }
373 
374 static void __exit exit_arxe_scsi_driver(void)
375 {
376  ecard_remove_driver(&arxescsi_driver);
377 }
378 
379 module_init(init_arxe_scsi_driver);
380 module_exit(exit_arxe_scsi_driver);
381 
382 MODULE_AUTHOR("Stefan Hanske");
383 MODULE_DESCRIPTION("ARXESCSI driver for Acorn machines");
384 MODULE_LICENSE("GPL");
385 
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