xref: /openbmc/linux/drivers/scsi/arm/arxescsi.c (revision 9123e3a7)
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.h"
39 #include <scsi/scsi_host.h>
40 #include "fas216.h"
41 
42 struct arxescsi_info {
43 	FAS216_Info		info;
44 	struct expansion_card	*ec;
45 	void __iomem		*base;
46 };
47 
48 #define DMADATA_OFFSET	(0x200)
49 
50 #define DMASTAT_OFFSET	(0x600)
51 #define DMASTAT_DRQ	(1 << 0)
52 
53 #define CSTATUS_IRQ	(1 << 0)
54 
55 #define VERSION "1.10 (23/01/2003 2.5.57)"
56 
57 /*
58  * Function: int arxescsi_dma_setup(host, SCpnt, direction, min_type)
59  * Purpose : initialises DMA/PIO
60  * Params  : host      - host
61  *	     SCpnt     - command
62  *	     direction - DMA on to/off of card
63  *	     min_type  - minimum DMA support that we must have for this transfer
64  * Returns : 0 if we should not set CMD_WITHDMA for transfer info command
65  */
66 static fasdmatype_t
67 arxescsi_dma_setup(struct Scsi_Host *host, struct scsi_pointer *SCp,
68 		       fasdmadir_t direction, fasdmatype_t min_type)
69 {
70 	/*
71 	 * We don't do real DMA
72 	 */
73 	return fasdma_pseudo;
74 }
75 
76 static void arxescsi_pseudo_dma_write(unsigned char *addr, void __iomem *base)
77 {
78        __asm__ __volatile__(
79        "               stmdb   sp!, {r0-r12}\n"
80        "               mov     r3, %0\n"
81        "               mov     r1, %1\n"
82        "               add     r2, r1, #512\n"
83        "               mov     r4, #256\n"
84        ".loop_1:       ldmia   r3!, {r6, r8, r10, r12}\n"
85        "               mov     r5, r6, lsl #16\n"
86        "               mov     r7, r8, lsl #16\n"
87        ".loop_2:       ldrb    r0, [r1, #1536]\n"
88        "               tst     r0, #1\n"
89        "               beq     .loop_2\n"
90        "               stmia   r2, {r5-r8}\n\t"
91        "               mov     r9, r10, lsl #16\n"
92        "               mov     r11, r12, lsl #16\n"
93        ".loop_3:       ldrb    r0, [r1, #1536]\n"
94        "               tst     r0, #1\n"
95        "               beq     .loop_3\n"
96        "               stmia   r2, {r9-r12}\n"
97        "               subs    r4, r4, #16\n"
98        "               bne     .loop_1\n"
99        "               ldmia   sp!, {r0-r12}\n"
100        :
101        : "r" (addr), "r" (base));
102 }
103 
104 /*
105  * Function: int arxescsi_dma_pseudo(host, SCpnt, direction, transfer)
106  * Purpose : handles pseudo DMA
107  * Params  : host      - host
108  *	     SCpnt     - command
109  *	     direction - DMA on to/off of card
110  *	     transfer  - minimum number of bytes we expect to transfer
111  */
112 static void
113 arxescsi_dma_pseudo(struct Scsi_Host *host, struct scsi_pointer *SCp,
114 		    fasdmadir_t direction, int transfer)
115 {
116 	struct arxescsi_info *info = (struct arxescsi_info *)host->hostdata;
117 	unsigned int length, error = 0;
118 	void __iomem *base = info->info.scsi.io_base;
119 	unsigned char *addr;
120 
121 	length = SCp->this_residual;
122 	addr = SCp->ptr;
123 
124 	if (direction == DMA_OUT) {
125 		unsigned int word;
126 		while (length > 256) {
127 			if (readb(base + 0x80) & STAT_INT) {
128 				error = 1;
129 				break;
130 			}
131 			arxescsi_pseudo_dma_write(addr, base);
132 			addr += 256;
133 			length -= 256;
134 		}
135 
136 		if (!error)
137 			while (length > 0) {
138 				if (readb(base + 0x80) & STAT_INT)
139 					break;
140 
141 				if (!(readb(base + DMASTAT_OFFSET) & DMASTAT_DRQ))
142 					continue;
143 
144 				word = *addr | *(addr + 1) << 8;
145 
146 				writew(word, base + DMADATA_OFFSET);
147 				if (length > 1) {
148 					addr += 2;
149 					length -= 2;
150 				} else {
151 					addr += 1;
152 					length -= 1;
153 				}
154 			}
155 	}
156 	else {
157 		if (transfer && (transfer & 255)) {
158 			while (length >= 256) {
159 				if (readb(base + 0x80) & STAT_INT) {
160 					error = 1;
161 					break;
162 				}
163 
164 				if (!(readb(base + DMASTAT_OFFSET) & DMASTAT_DRQ))
165 					continue;
166 
167 				readsw(base + DMADATA_OFFSET, addr, 256 >> 1);
168 				addr += 256;
169 				length -= 256;
170 			}
171 		}
172 
173 		if (!(error))
174 			while (length > 0) {
175 				unsigned long word;
176 
177 				if (readb(base + 0x80) & STAT_INT)
178 					break;
179 
180 				if (!(readb(base + DMASTAT_OFFSET) & DMASTAT_DRQ))
181 					continue;
182 
183 				word = readw(base + DMADATA_OFFSET);
184 				*addr++ = word;
185 				if (--length > 0) {
186 					*addr++ = word >> 8;
187 					length --;
188 				}
189 			}
190 	}
191 }
192 
193 /*
194  * Function: int arxescsi_dma_stop(host, SCpnt)
195  * Purpose : stops DMA/PIO
196  * Params  : host  - host
197  *	     SCpnt - command
198  */
199 static void arxescsi_dma_stop(struct Scsi_Host *host, struct scsi_pointer *SCp)
200 {
201 	/*
202 	 * no DMA to stop
203 	 */
204 }
205 
206 /*
207  * Function: const char *arxescsi_info(struct Scsi_Host * host)
208  * Purpose : returns a descriptive string about this interface,
209  * Params  : host - driver host structure to return info for.
210  * Returns : pointer to a static buffer containing null terminated string.
211  */
212 static const char *arxescsi_info(struct Scsi_Host *host)
213 {
214 	struct arxescsi_info *info = (struct arxescsi_info *)host->hostdata;
215 	static char string[150];
216 
217 	sprintf(string, "%s (%s) in slot %d v%s",
218 		host->hostt->name, info->info.scsi.type, info->ec->slot_no,
219 		VERSION);
220 
221 	return string;
222 }
223 
224 static int
225 arxescsi_show_info(struct seq_file *m, struct Scsi_Host *host)
226 {
227 	struct arxescsi_info *info;
228 	info = (struct arxescsi_info *)host->hostdata;
229 
230 	seq_printf(m, "ARXE 16-bit SCSI driver v%s\n", VERSION);
231 	fas216_print_host(&info->info, m);
232 	fas216_print_stats(&info->info, m);
233 	fas216_print_devices(&info->info, m);
234 	return 0;
235 }
236 
237 static struct scsi_host_template arxescsi_template = {
238 	.show_info			= arxescsi_show_info,
239 	.name				= "ARXE SCSI card",
240 	.info				= arxescsi_info,
241 	.queuecommand			= fas216_noqueue_command,
242 	.eh_host_reset_handler		= fas216_eh_host_reset,
243 	.eh_bus_reset_handler		= fas216_eh_bus_reset,
244 	.eh_device_reset_handler	= fas216_eh_device_reset,
245 	.eh_abort_handler		= fas216_eh_abort,
246 	.can_queue			= 0,
247 	.this_id			= 7,
248 	.sg_tablesize			= SG_ALL,
249 	.dma_boundary			= PAGE_SIZE - 1,
250 	.proc_name			= "arxescsi",
251 };
252 
253 static int arxescsi_probe(struct expansion_card *ec, const struct ecard_id *id)
254 {
255 	struct Scsi_Host *host;
256 	struct arxescsi_info *info;
257 	void __iomem *base;
258 	int ret;
259 
260 	ret = ecard_request_resources(ec);
261 	if (ret)
262 		goto out;
263 
264 	base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
265 	if (!base) {
266 		ret = -ENOMEM;
267 		goto out_region;
268 	}
269 
270 	host = scsi_host_alloc(&arxescsi_template, sizeof(struct arxescsi_info));
271 	if (!host) {
272 		ret = -ENOMEM;
273 		goto out_region;
274 	}
275 
276 	info = (struct arxescsi_info *)host->hostdata;
277 	info->ec = ec;
278 	info->base = base;
279 
280 	info->info.scsi.io_base		= base + 0x2000;
281 	info->info.scsi.irq		= 0;
282 	info->info.scsi.dma		= NO_DMA;
283 	info->info.scsi.io_shift	= 5;
284 	info->info.ifcfg.clockrate	= 24; /* MHz */
285 	info->info.ifcfg.select_timeout = 255;
286 	info->info.ifcfg.asyncperiod	= 200; /* ns */
287 	info->info.ifcfg.sync_max_depth	= 0;
288 	info->info.ifcfg.cntl3		= CNTL3_FASTSCSI | CNTL3_FASTCLK;
289 	info->info.ifcfg.disconnect_ok	= 0;
290 	info->info.ifcfg.wide_max_size	= 0;
291 	info->info.ifcfg.capabilities	= FASCAP_PSEUDODMA;
292 	info->info.dma.setup		= arxescsi_dma_setup;
293 	info->info.dma.pseudo		= arxescsi_dma_pseudo;
294 	info->info.dma.stop		= arxescsi_dma_stop;
295 
296 	ec->irqaddr = base;
297 	ec->irqmask = CSTATUS_IRQ;
298 
299 	ret = fas216_init(host);
300 	if (ret)
301 		goto out_unregister;
302 
303 	ret = fas216_add(host, &ec->dev);
304 	if (ret == 0)
305 		goto out;
306 
307 	fas216_release(host);
308  out_unregister:
309 	scsi_host_put(host);
310  out_region:
311 	ecard_release_resources(ec);
312  out:
313 	return ret;
314 }
315 
316 static void arxescsi_remove(struct expansion_card *ec)
317 {
318 	struct Scsi_Host *host = ecard_get_drvdata(ec);
319 
320 	ecard_set_drvdata(ec, NULL);
321 	fas216_remove(host);
322 
323 	fas216_release(host);
324 	scsi_host_put(host);
325 	ecard_release_resources(ec);
326 }
327 
328 static const struct ecard_id arxescsi_cids[] = {
329 	{ MANU_ARXE, PROD_ARXE_SCSI },
330 	{ 0xffff, 0xffff },
331 };
332 
333 static struct ecard_driver arxescsi_driver = {
334 	.probe		= arxescsi_probe,
335 	.remove		= arxescsi_remove,
336 	.id_table	= arxescsi_cids,
337 	.drv = {
338 		.name		= "arxescsi",
339 	},
340 };
341 
342 static int __init init_arxe_scsi_driver(void)
343 {
344 	return ecard_register_driver(&arxescsi_driver);
345 }
346 
347 static void __exit exit_arxe_scsi_driver(void)
348 {
349 	ecard_remove_driver(&arxescsi_driver);
350 }
351 
352 module_init(init_arxe_scsi_driver);
353 module_exit(exit_arxe_scsi_driver);
354 
355 MODULE_AUTHOR("Stefan Hanske");
356 MODULE_DESCRIPTION("ARXESCSI driver for Acorn machines");
357 MODULE_LICENSE("GPL");
358 
359