xref: /openbmc/linux/drivers/scsi/a2091.c (revision 0545810f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/types.h>
3 #include <linux/init.h>
4 #include <linux/interrupt.h>
5 #include <linux/mm.h>
6 #include <linux/slab.h>
7 #include <linux/spinlock.h>
8 #include <linux/zorro.h>
9 #include <linux/module.h>
10 
11 #include <asm/page.h>
12 #include <asm/amigaints.h>
13 #include <asm/amigahw.h>
14 
15 #include <scsi/scsi.h>
16 #include <scsi/scsi_cmnd.h>
17 #include <scsi/scsi_device.h>
18 #include <scsi/scsi_eh.h>
19 #include <scsi/scsi_tcq.h>
20 #include "wd33c93.h"
21 #include "a2091.h"
22 
23 
24 struct a2091_hostdata {
25 	struct WD33C93_hostdata wh;
26 	struct a2091_scsiregs *regs;
27 	struct device *dev;
28 };
29 
30 #define DMA_DIR(d)   ((d == DATA_OUT_DIR) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
31 
32 static irqreturn_t a2091_intr(int irq, void *data)
33 {
34 	struct Scsi_Host *instance = data;
35 	struct a2091_hostdata *hdata = shost_priv(instance);
36 	unsigned int status = hdata->regs->ISTR;
37 	unsigned long flags;
38 
39 	if (!(status & (ISTR_INT_F | ISTR_INT_P)) || !(status & ISTR_INTS))
40 		return IRQ_NONE;
41 
42 	spin_lock_irqsave(instance->host_lock, flags);
43 	wd33c93_intr(instance);
44 	spin_unlock_irqrestore(instance->host_lock, flags);
45 	return IRQ_HANDLED;
46 }
47 
48 static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
49 {
50 	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
51 	unsigned long len = scsi_pointer->this_residual;
52 	struct Scsi_Host *instance = cmd->device->host;
53 	struct a2091_hostdata *hdata = shost_priv(instance);
54 	struct WD33C93_hostdata *wh = &hdata->wh;
55 	struct a2091_scsiregs *regs = hdata->regs;
56 	unsigned short cntr = CNTR_PDMD | CNTR_INTEN;
57 	dma_addr_t addr;
58 
59 	addr = dma_map_single(hdata->dev, scsi_pointer->ptr,
60 			      len, DMA_DIR(dir_in));
61 	if (dma_mapping_error(hdata->dev, addr)) {
62 		dev_warn(hdata->dev, "cannot map SCSI data block %p\n",
63 			 scsi_pointer->ptr);
64 		return 1;
65 	}
66 	scsi_pointer->dma_handle = addr;
67 
68 	/* don't allow DMA if the physical address is bad */
69 	if (addr & A2091_XFER_MASK) {
70 		/* drop useless mapping */
71 		dma_unmap_single(hdata->dev, scsi_pointer->dma_handle,
72 				 scsi_pointer->this_residual,
73 				 DMA_DIR(dir_in));
74 		scsi_pointer->dma_handle = (dma_addr_t) NULL;
75 
76 		wh->dma_bounce_len = (scsi_pointer->this_residual + 511) & ~0x1ff;
77 		wh->dma_bounce_buffer = kmalloc(wh->dma_bounce_len,
78 						GFP_KERNEL);
79 
80 		/* can't allocate memory; use PIO */
81 		if (!wh->dma_bounce_buffer) {
82 			wh->dma_bounce_len = 0;
83 			return 1;
84 		}
85 
86 		if (!dir_in) {
87 			/* copy to bounce buffer for a write */
88 			memcpy(wh->dma_bounce_buffer, scsi_pointer->ptr,
89 			       scsi_pointer->this_residual);
90 		}
91 
92 		/* will flush/invalidate cache for us */
93 		addr = dma_map_single(hdata->dev, wh->dma_bounce_buffer,
94 				      wh->dma_bounce_len, DMA_DIR(dir_in));
95 		/* can't map buffer; use PIO */
96 		if (dma_mapping_error(hdata->dev, addr)) {
97 			dev_warn(hdata->dev, "cannot map bounce buffer %p\n",
98 				 wh->dma_bounce_buffer);
99 			return 1;
100 		}
101 
102 		/* the bounce buffer may not be in the first 16M of physmem */
103 		if (addr & A2091_XFER_MASK) {
104 			/* we could use chipmem... maybe later */
105 			kfree(wh->dma_bounce_buffer);
106 			wh->dma_bounce_buffer = NULL;
107 			wh->dma_bounce_len = 0;
108 			return 1;
109 		}
110 
111 		scsi_pointer->dma_handle = addr;
112 	}
113 
114 	/* setup dma direction */
115 	if (!dir_in)
116 		cntr |= CNTR_DDIR;
117 
118 	/* remember direction */
119 	wh->dma_dir = dir_in;
120 
121 	regs->CNTR = cntr;
122 
123 	/* setup DMA *physical* address */
124 	regs->ACR = addr;
125 
126 	/* no more cache flush here - dma_map_single() takes care */
127 
128 	/* start DMA */
129 	regs->ST_DMA = 1;
130 
131 	/* return success */
132 	return 0;
133 }
134 
135 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
136 		     int status)
137 {
138 	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(SCpnt);
139 	struct a2091_hostdata *hdata = shost_priv(instance);
140 	struct WD33C93_hostdata *wh = &hdata->wh;
141 	struct a2091_scsiregs *regs = hdata->regs;
142 
143 	/* disable SCSI interrupts */
144 	unsigned short cntr = CNTR_PDMD;
145 
146 	if (!wh->dma_dir)
147 		cntr |= CNTR_DDIR;
148 
149 	/* disable SCSI interrupts */
150 	regs->CNTR = cntr;
151 
152 	/* flush if we were reading */
153 	if (wh->dma_dir) {
154 		regs->FLUSH = 1;
155 		while (!(regs->ISTR & ISTR_FE_FLG))
156 			;
157 	}
158 
159 	/* clear a possible interrupt */
160 	regs->CINT = 1;
161 
162 	/* stop DMA */
163 	regs->SP_DMA = 1;
164 
165 	/* restore the CONTROL bits (minus the direction flag) */
166 	regs->CNTR = CNTR_PDMD | CNTR_INTEN;
167 
168 	dma_unmap_single(hdata->dev, scsi_pointer->dma_handle,
169 			 scsi_pointer->this_residual,
170 			 DMA_DIR(wh->dma_dir));
171 
172 	/* copy from a bounce buffer, if necessary */
173 	if (status && wh->dma_bounce_buffer) {
174 		if (wh->dma_dir)
175 			memcpy(scsi_pointer->ptr, wh->dma_bounce_buffer,
176 			       scsi_pointer->this_residual);
177 		kfree(wh->dma_bounce_buffer);
178 		wh->dma_bounce_buffer = NULL;
179 		wh->dma_bounce_len = 0;
180 	}
181 }
182 
183 static const struct scsi_host_template a2091_scsi_template = {
184 	.module			= THIS_MODULE,
185 	.name			= "Commodore A2091/A590 SCSI",
186 	.show_info		= wd33c93_show_info,
187 	.write_info		= wd33c93_write_info,
188 	.proc_name		= "A2901",
189 	.queuecommand		= wd33c93_queuecommand,
190 	.eh_abort_handler	= wd33c93_abort,
191 	.eh_host_reset_handler	= wd33c93_host_reset,
192 	.can_queue		= CAN_QUEUE,
193 	.this_id		= 7,
194 	.sg_tablesize		= SG_ALL,
195 	.cmd_per_lun		= CMD_PER_LUN,
196 	.dma_boundary		= PAGE_SIZE - 1,
197 	.cmd_size		= sizeof(struct scsi_pointer),
198 };
199 
200 static int a2091_probe(struct zorro_dev *z, const struct zorro_device_id *ent)
201 {
202 	struct Scsi_Host *instance;
203 	int error;
204 	struct a2091_scsiregs *regs;
205 	wd33c93_regs wdregs;
206 	struct a2091_hostdata *hdata;
207 
208 	if (dma_set_mask_and_coherent(&z->dev, DMA_BIT_MASK(24))) {
209 		dev_warn(&z->dev, "cannot use 24 bit DMA\n");
210 		return -ENODEV;
211 	}
212 
213 	if (!request_mem_region(z->resource.start, 256, "wd33c93"))
214 		return -EBUSY;
215 
216 	instance = scsi_host_alloc(&a2091_scsi_template,
217 				   sizeof(struct a2091_hostdata));
218 	if (!instance) {
219 		error = -ENOMEM;
220 		goto fail_alloc;
221 	}
222 
223 	instance->irq = IRQ_AMIGA_PORTS;
224 	instance->unique_id = z->slotaddr;
225 
226 	regs = ZTWO_VADDR(z->resource.start);
227 	regs->DAWR = DAWR_A2091;
228 
229 	wdregs.SASR = &regs->SASR;
230 	wdregs.SCMD = &regs->SCMD;
231 
232 	hdata = shost_priv(instance);
233 	hdata->dev = &z->dev;
234 	hdata->wh.no_sync = 0xff;
235 	hdata->wh.fast = 0;
236 	hdata->wh.dma_mode = CTRL_DMA;
237 	hdata->regs = regs;
238 
239 	wd33c93_init(instance, wdregs, dma_setup, dma_stop, WD33C93_FS_8_10);
240 	error = request_irq(IRQ_AMIGA_PORTS, a2091_intr, IRQF_SHARED,
241 			    "A2091 SCSI", instance);
242 	if (error)
243 		goto fail_irq;
244 
245 	regs->CNTR = CNTR_PDMD | CNTR_INTEN;
246 
247 	error = scsi_add_host(instance, NULL);
248 	if (error)
249 		goto fail_host;
250 
251 	zorro_set_drvdata(z, instance);
252 
253 	scsi_scan_host(instance);
254 	return 0;
255 
256 fail_host:
257 	free_irq(IRQ_AMIGA_PORTS, instance);
258 fail_irq:
259 	scsi_host_put(instance);
260 fail_alloc:
261 	release_mem_region(z->resource.start, 256);
262 	return error;
263 }
264 
265 static void a2091_remove(struct zorro_dev *z)
266 {
267 	struct Scsi_Host *instance = zorro_get_drvdata(z);
268 	struct a2091_hostdata *hdata = shost_priv(instance);
269 
270 	hdata->regs->CNTR = 0;
271 	scsi_remove_host(instance);
272 	free_irq(IRQ_AMIGA_PORTS, instance);
273 	scsi_host_put(instance);
274 	release_mem_region(z->resource.start, 256);
275 }
276 
277 static struct zorro_device_id a2091_zorro_tbl[] = {
278 	{ ZORRO_PROD_CBM_A590_A2091_1 },
279 	{ ZORRO_PROD_CBM_A590_A2091_2 },
280 	{ 0 }
281 };
282 MODULE_DEVICE_TABLE(zorro, a2091_zorro_tbl);
283 
284 static struct zorro_driver a2091_driver = {
285 	.name		= "a2091",
286 	.id_table	= a2091_zorro_tbl,
287 	.probe		= a2091_probe,
288 	.remove		= a2091_remove,
289 };
290 
291 static int __init a2091_init(void)
292 {
293 	return zorro_register_driver(&a2091_driver);
294 }
295 module_init(a2091_init);
296 
297 static void __exit a2091_exit(void)
298 {
299 	zorro_unregister_driver(&a2091_driver);
300 }
301 module_exit(a2091_exit);
302 
303 MODULE_DESCRIPTION("Commodore A2091/A590 SCSI");
304 MODULE_LICENSE("GPL");
305