xref: /openbmc/linux/drivers/scsi/arm/arxescsi.c (revision 6a87e0f0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * linux/drivers/scsi/arm/arxescsi.c
4  *
5  * Copyright (C) 1997-2000 Russell King, Stefan Hanske
6  *
7  * This driver is based on experimentation.  Hence, it may have made
8  * assumptions about the particular card that I have available, and
9  * may not be reliable!
10  *
11  * Changelog:
12  *  30-08-1997	RMK	0.0.0	Created, READONLY version as cumana_2.c
13  *  22-01-1998	RMK	0.0.1	Updated to 2.1.80
14  *  15-04-1998	RMK	0.0.1	Only do PIO if FAS216 will allow it.
15  *  11-06-1998 	SH	0.0.2   Changed to support ARXE 16-bit SCSI card
16  *				enabled writing
17  *  01-01-2000	SH	0.1.0   Added *real* pseudo dma writing
18  *				(arxescsi_pseudo_dma_write)
19  *  02-04-2000	RMK	0.1.1	Updated for new error handling code.
20  *  22-10-2000  SH		Updated for new registering scheme.
21  */
22 #include <linux/module.h>
23 #include <linux/blkdev.h>
24 #include <linux/kernel.h>
25 #include <linux/string.h>
26 #include <linux/ioport.h>
27 #include <linux/proc_fs.h>
28 #include <linux/unistd.h>
29 #include <linux/stat.h>
30 #include <linux/delay.h>
31 #include <linux/init.h>
32 #include <linux/interrupt.h>
33 
34 #include <asm/dma.h>
35 #include <asm/io.h>
36 #include <asm/ecard.h>
37 
38 #include <scsi/scsi.h>
39 #include <scsi/scsi_cmnd.h>
40 #include <scsi/scsi_device.h>
41 #include <scsi/scsi_eh.h>
42 #include <scsi/scsi_host.h>
43 #include <scsi/scsi_tcq.h>
44 #include "fas216.h"
45 
46 struct arxescsi_info {
47 	FAS216_Info		info;
48 	struct expansion_card	*ec;
49 	void __iomem		*base;
50 };
51 
52 #define DMADATA_OFFSET	(0x200)
53 
54 #define DMASTAT_OFFSET	(0x600)
55 #define DMASTAT_DRQ	(1 << 0)
56 
57 #define CSTATUS_IRQ	(1 << 0)
58 
59 #define VERSION "1.10 (23/01/2003 2.5.57)"
60 
61 /*
62  * Function: int arxescsi_dma_setup(host, SCpnt, direction, min_type)
63  * Purpose : initialises DMA/PIO
64  * Params  : host      - host
65  *	     SCpnt     - command
66  *	     direction - DMA on to/off of card
67  *	     min_type  - minimum DMA support that we must have for this transfer
68  * Returns : 0 if we should not set CMD_WITHDMA for transfer info command
69  */
70 static fasdmatype_t
71 arxescsi_dma_setup(struct Scsi_Host *host, struct scsi_pointer *SCp,
72 		       fasdmadir_t direction, fasdmatype_t min_type)
73 {
74 	/*
75 	 * We don't do real DMA
76 	 */
77 	return fasdma_pseudo;
78 }
79 
80 static void arxescsi_pseudo_dma_write(unsigned char *addr, void __iomem *base)
81 {
82        __asm__ __volatile__(
83        "               stmdb   sp!, {r0-r12}\n"
84        "               mov     r3, %0\n"
85        "               mov     r1, %1\n"
86        "               add     r2, r1, #512\n"
87        "               mov     r4, #256\n"
88        ".loop_1:       ldmia   r3!, {r6, r8, r10, r12}\n"
89        "               mov     r5, r6, lsl #16\n"
90        "               mov     r7, r8, lsl #16\n"
91        ".loop_2:       ldrb    r0, [r1, #1536]\n"
92        "               tst     r0, #1\n"
93        "               beq     .loop_2\n"
94        "               stmia   r2, {r5-r8}\n\t"
95        "               mov     r9, r10, lsl #16\n"
96        "               mov     r11, r12, lsl #16\n"
97        ".loop_3:       ldrb    r0, [r1, #1536]\n"
98        "               tst     r0, #1\n"
99        "               beq     .loop_3\n"
100        "               stmia   r2, {r9-r12}\n"
101        "               subs    r4, r4, #16\n"
102        "               bne     .loop_1\n"
103        "               ldmia   sp!, {r0-r12}\n"
104        :
105        : "r" (addr), "r" (base));
106 }
107 
108 /*
109  * Function: int arxescsi_dma_pseudo(host, SCpnt, direction, transfer)
110  * Purpose : handles pseudo DMA
111  * Params  : host      - host
112  *	     SCpnt     - command
113  *	     direction - DMA on to/off of card
114  *	     transfer  - minimum number of bytes we expect to transfer
115  */
116 static void
117 arxescsi_dma_pseudo(struct Scsi_Host *host, struct scsi_pointer *SCp,
118 		    fasdmadir_t direction, int transfer)
119 {
120 	struct arxescsi_info *info = (struct arxescsi_info *)host->hostdata;
121 	unsigned int length, error = 0;
122 	void __iomem *base = info->info.scsi.io_base;
123 	unsigned char *addr;
124 
125 	length = SCp->this_residual;
126 	addr = SCp->ptr;
127 
128 	if (direction == DMA_OUT) {
129 		unsigned int word;
130 		while (length > 256) {
131 			if (readb(base + 0x80) & STAT_INT) {
132 				error = 1;
133 				break;
134 			}
135 			arxescsi_pseudo_dma_write(addr, base);
136 			addr += 256;
137 			length -= 256;
138 		}
139 
140 		if (!error)
141 			while (length > 0) {
142 				if (readb(base + 0x80) & STAT_INT)
143 					break;
144 
145 				if (!(readb(base + DMASTAT_OFFSET) & DMASTAT_DRQ))
146 					continue;
147 
148 				word = *addr | *(addr + 1) << 8;
149 
150 				writew(word, base + DMADATA_OFFSET);
151 				if (length > 1) {
152 					addr += 2;
153 					length -= 2;
154 				} else {
155 					addr += 1;
156 					length -= 1;
157 				}
158 			}
159 	}
160 	else {
161 		if (transfer && (transfer & 255)) {
162 			while (length >= 256) {
163 				if (readb(base + 0x80) & STAT_INT) {
164 					error = 1;
165 					break;
166 				}
167 
168 				if (!(readb(base + DMASTAT_OFFSET) & DMASTAT_DRQ))
169 					continue;
170 
171 				readsw(base + DMADATA_OFFSET, addr, 256 >> 1);
172 				addr += 256;
173 				length -= 256;
174 			}
175 		}
176 
177 		if (!(error))
178 			while (length > 0) {
179 				unsigned long word;
180 
181 				if (readb(base + 0x80) & STAT_INT)
182 					break;
183 
184 				if (!(readb(base + DMASTAT_OFFSET) & DMASTAT_DRQ))
185 					continue;
186 
187 				word = readw(base + DMADATA_OFFSET);
188 				*addr++ = word;
189 				if (--length > 0) {
190 					*addr++ = word >> 8;
191 					length --;
192 				}
193 			}
194 	}
195 }
196 
197 /*
198  * Function: int arxescsi_dma_stop(host, SCpnt)
199  * Purpose : stops DMA/PIO
200  * Params  : host  - host
201  *	     SCpnt - command
202  */
203 static void arxescsi_dma_stop(struct Scsi_Host *host, struct scsi_pointer *SCp)
204 {
205 	/*
206 	 * no DMA to stop
207 	 */
208 }
209 
210 /*
211  * Function: const char *arxescsi_info(struct Scsi_Host * host)
212  * Purpose : returns a descriptive string about this interface,
213  * Params  : host - driver host structure to return info for.
214  * Returns : pointer to a static buffer containing null terminated string.
215  */
216 static const char *arxescsi_info(struct Scsi_Host *host)
217 {
218 	struct arxescsi_info *info = (struct arxescsi_info *)host->hostdata;
219 	static char string[150];
220 
221 	sprintf(string, "%s (%s) in slot %d v%s",
222 		host->hostt->name, info->info.scsi.type, info->ec->slot_no,
223 		VERSION);
224 
225 	return string;
226 }
227 
228 static int
229 arxescsi_show_info(struct seq_file *m, struct Scsi_Host *host)
230 {
231 	struct arxescsi_info *info;
232 	info = (struct arxescsi_info *)host->hostdata;
233 
234 	seq_printf(m, "ARXE 16-bit SCSI driver v%s\n", VERSION);
235 	fas216_print_host(&info->info, m);
236 	fas216_print_stats(&info->info, m);
237 	fas216_print_devices(&info->info, m);
238 	return 0;
239 }
240 
241 static const struct scsi_host_template arxescsi_template = {
242 	.show_info			= arxescsi_show_info,
243 	.name				= "ARXE SCSI card",
244 	.info				= arxescsi_info,
245 	.queuecommand			= fas216_noqueue_command,
246 	.eh_host_reset_handler		= fas216_eh_host_reset,
247 	.eh_bus_reset_handler		= fas216_eh_bus_reset,
248 	.eh_device_reset_handler	= fas216_eh_device_reset,
249 	.eh_abort_handler		= fas216_eh_abort,
250 	.cmd_size			= sizeof(struct fas216_cmd_priv),
251 	.can_queue			= 0,
252 	.this_id			= 7,
253 	.sg_tablesize			= SG_ALL,
254 	.dma_boundary			= PAGE_SIZE - 1,
255 	.proc_name			= "arxescsi",
256 };
257 
258 static int arxescsi_probe(struct expansion_card *ec, const struct ecard_id *id)
259 {
260 	struct Scsi_Host *host;
261 	struct arxescsi_info *info;
262 	void __iomem *base;
263 	int ret;
264 
265 	ret = ecard_request_resources(ec);
266 	if (ret)
267 		goto out;
268 
269 	base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
270 	if (!base) {
271 		ret = -ENOMEM;
272 		goto out_region;
273 	}
274 
275 	host = scsi_host_alloc(&arxescsi_template, sizeof(struct arxescsi_info));
276 	if (!host) {
277 		ret = -ENOMEM;
278 		goto out_region;
279 	}
280 
281 	info = (struct arxescsi_info *)host->hostdata;
282 	info->ec = ec;
283 	info->base = base;
284 
285 	info->info.scsi.io_base		= base + 0x2000;
286 	info->info.scsi.irq		= 0;
287 	info->info.scsi.dma		= NO_DMA;
288 	info->info.scsi.io_shift	= 5;
289 	info->info.ifcfg.clockrate	= 24; /* MHz */
290 	info->info.ifcfg.select_timeout = 255;
291 	info->info.ifcfg.asyncperiod	= 200; /* ns */
292 	info->info.ifcfg.sync_max_depth	= 0;
293 	info->info.ifcfg.cntl3		= CNTL3_FASTSCSI | CNTL3_FASTCLK;
294 	info->info.ifcfg.disconnect_ok	= 0;
295 	info->info.ifcfg.wide_max_size	= 0;
296 	info->info.ifcfg.capabilities	= FASCAP_PSEUDODMA;
297 	info->info.dma.setup		= arxescsi_dma_setup;
298 	info->info.dma.pseudo		= arxescsi_dma_pseudo;
299 	info->info.dma.stop		= arxescsi_dma_stop;
300 
301 	ec->irqaddr = base;
302 	ec->irqmask = CSTATUS_IRQ;
303 
304 	ret = fas216_init(host);
305 	if (ret)
306 		goto out_unregister;
307 
308 	ret = fas216_add(host, &ec->dev);
309 	if (ret == 0)
310 		goto out;
311 
312 	fas216_release(host);
313  out_unregister:
314 	scsi_host_put(host);
315  out_region:
316 	ecard_release_resources(ec);
317  out:
318 	return ret;
319 }
320 
321 static void arxescsi_remove(struct expansion_card *ec)
322 {
323 	struct Scsi_Host *host = ecard_get_drvdata(ec);
324 
325 	ecard_set_drvdata(ec, NULL);
326 	fas216_remove(host);
327 
328 	fas216_release(host);
329 	scsi_host_put(host);
330 	ecard_release_resources(ec);
331 }
332 
333 static const struct ecard_id arxescsi_cids[] = {
334 	{ MANU_ARXE, PROD_ARXE_SCSI },
335 	{ 0xffff, 0xffff },
336 };
337 
338 static struct ecard_driver arxescsi_driver = {
339 	.probe		= arxescsi_probe,
340 	.remove		= arxescsi_remove,
341 	.id_table	= arxescsi_cids,
342 	.drv = {
343 		.name		= "arxescsi",
344 	},
345 };
346 
347 static int __init init_arxe_scsi_driver(void)
348 {
349 	return ecard_register_driver(&arxescsi_driver);
350 }
351 
352 static void __exit exit_arxe_scsi_driver(void)
353 {
354 	ecard_remove_driver(&arxescsi_driver);
355 }
356 
357 module_init(init_arxe_scsi_driver);
358 module_exit(exit_arxe_scsi_driver);
359 
360 MODULE_AUTHOR("Stefan Hanske");
361 MODULE_DESCRIPTION("ARXESCSI driver for Acorn machines");
362 MODULE_LICENSE("GPL");
363 
364