xref: /openbmc/linux/drivers/scsi/a2091.c (revision 4e95bc26)
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/pgtable.h>
13 #include <asm/amigaints.h>
14 #include <asm/amigahw.h>
15 
16 #include "scsi.h"
17 #include "wd33c93.h"
18 #include "a2091.h"
19 
20 
21 struct a2091_hostdata {
22 	struct WD33C93_hostdata wh;
23 	struct a2091_scsiregs *regs;
24 };
25 
26 static irqreturn_t a2091_intr(int irq, void *data)
27 {
28 	struct Scsi_Host *instance = data;
29 	struct a2091_hostdata *hdata = shost_priv(instance);
30 	unsigned int status = hdata->regs->ISTR;
31 	unsigned long flags;
32 
33 	if (!(status & (ISTR_INT_F | ISTR_INT_P)) || !(status & ISTR_INTS))
34 		return IRQ_NONE;
35 
36 	spin_lock_irqsave(instance->host_lock, flags);
37 	wd33c93_intr(instance);
38 	spin_unlock_irqrestore(instance->host_lock, flags);
39 	return IRQ_HANDLED;
40 }
41 
42 static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
43 {
44 	struct Scsi_Host *instance = cmd->device->host;
45 	struct a2091_hostdata *hdata = shost_priv(instance);
46 	struct WD33C93_hostdata *wh = &hdata->wh;
47 	struct a2091_scsiregs *regs = hdata->regs;
48 	unsigned short cntr = CNTR_PDMD | CNTR_INTEN;
49 	unsigned long addr = virt_to_bus(cmd->SCp.ptr);
50 
51 	/* don't allow DMA if the physical address is bad */
52 	if (addr & A2091_XFER_MASK) {
53 		wh->dma_bounce_len = (cmd->SCp.this_residual + 511) & ~0x1ff;
54 		wh->dma_bounce_buffer = kmalloc(wh->dma_bounce_len,
55 						GFP_KERNEL);
56 
57 		/* can't allocate memory; use PIO */
58 		if (!wh->dma_bounce_buffer) {
59 			wh->dma_bounce_len = 0;
60 			return 1;
61 		}
62 
63 		/* get the physical address of the bounce buffer */
64 		addr = virt_to_bus(wh->dma_bounce_buffer);
65 
66 		/* the bounce buffer may not be in the first 16M of physmem */
67 		if (addr & A2091_XFER_MASK) {
68 			/* we could use chipmem... maybe later */
69 			kfree(wh->dma_bounce_buffer);
70 			wh->dma_bounce_buffer = NULL;
71 			wh->dma_bounce_len = 0;
72 			return 1;
73 		}
74 
75 		if (!dir_in) {
76 			/* copy to bounce buffer for a write */
77 			memcpy(wh->dma_bounce_buffer, cmd->SCp.ptr,
78 			       cmd->SCp.this_residual);
79 		}
80 	}
81 
82 	/* setup dma direction */
83 	if (!dir_in)
84 		cntr |= CNTR_DDIR;
85 
86 	/* remember direction */
87 	wh->dma_dir = dir_in;
88 
89 	regs->CNTR = cntr;
90 
91 	/* setup DMA *physical* address */
92 	regs->ACR = addr;
93 
94 	if (dir_in) {
95 		/* invalidate any cache */
96 		cache_clear(addr, cmd->SCp.this_residual);
97 	} else {
98 		/* push any dirty cache */
99 		cache_push(addr, cmd->SCp.this_residual);
100 	}
101 	/* start DMA */
102 	regs->ST_DMA = 1;
103 
104 	/* return success */
105 	return 0;
106 }
107 
108 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
109 		     int status)
110 {
111 	struct a2091_hostdata *hdata = shost_priv(instance);
112 	struct WD33C93_hostdata *wh = &hdata->wh;
113 	struct a2091_scsiregs *regs = hdata->regs;
114 
115 	/* disable SCSI interrupts */
116 	unsigned short cntr = CNTR_PDMD;
117 
118 	if (!wh->dma_dir)
119 		cntr |= CNTR_DDIR;
120 
121 	/* disable SCSI interrupts */
122 	regs->CNTR = cntr;
123 
124 	/* flush if we were reading */
125 	if (wh->dma_dir) {
126 		regs->FLUSH = 1;
127 		while (!(regs->ISTR & ISTR_FE_FLG))
128 			;
129 	}
130 
131 	/* clear a possible interrupt */
132 	regs->CINT = 1;
133 
134 	/* stop DMA */
135 	regs->SP_DMA = 1;
136 
137 	/* restore the CONTROL bits (minus the direction flag) */
138 	regs->CNTR = CNTR_PDMD | CNTR_INTEN;
139 
140 	/* copy from a bounce buffer, if necessary */
141 	if (status && wh->dma_bounce_buffer) {
142 		if (wh->dma_dir)
143 			memcpy(SCpnt->SCp.ptr, wh->dma_bounce_buffer,
144 			       SCpnt->SCp.this_residual);
145 		kfree(wh->dma_bounce_buffer);
146 		wh->dma_bounce_buffer = NULL;
147 		wh->dma_bounce_len = 0;
148 	}
149 }
150 
151 static struct scsi_host_template a2091_scsi_template = {
152 	.module			= THIS_MODULE,
153 	.name			= "Commodore A2091/A590 SCSI",
154 	.show_info		= wd33c93_show_info,
155 	.write_info		= wd33c93_write_info,
156 	.proc_name		= "A2901",
157 	.queuecommand		= wd33c93_queuecommand,
158 	.eh_abort_handler	= wd33c93_abort,
159 	.eh_host_reset_handler	= wd33c93_host_reset,
160 	.can_queue		= CAN_QUEUE,
161 	.this_id		= 7,
162 	.sg_tablesize		= SG_ALL,
163 	.cmd_per_lun		= CMD_PER_LUN,
164 	.dma_boundary		= PAGE_SIZE - 1,
165 };
166 
167 static int a2091_probe(struct zorro_dev *z, const struct zorro_device_id *ent)
168 {
169 	struct Scsi_Host *instance;
170 	int error;
171 	struct a2091_scsiregs *regs;
172 	wd33c93_regs wdregs;
173 	struct a2091_hostdata *hdata;
174 
175 	if (!request_mem_region(z->resource.start, 256, "wd33c93"))
176 		return -EBUSY;
177 
178 	instance = scsi_host_alloc(&a2091_scsi_template,
179 				   sizeof(struct a2091_hostdata));
180 	if (!instance) {
181 		error = -ENOMEM;
182 		goto fail_alloc;
183 	}
184 
185 	instance->irq = IRQ_AMIGA_PORTS;
186 	instance->unique_id = z->slotaddr;
187 
188 	regs = ZTWO_VADDR(z->resource.start);
189 	regs->DAWR = DAWR_A2091;
190 
191 	wdregs.SASR = &regs->SASR;
192 	wdregs.SCMD = &regs->SCMD;
193 
194 	hdata = shost_priv(instance);
195 	hdata->wh.no_sync = 0xff;
196 	hdata->wh.fast = 0;
197 	hdata->wh.dma_mode = CTRL_DMA;
198 	hdata->regs = regs;
199 
200 	wd33c93_init(instance, wdregs, dma_setup, dma_stop, WD33C93_FS_8_10);
201 	error = request_irq(IRQ_AMIGA_PORTS, a2091_intr, IRQF_SHARED,
202 			    "A2091 SCSI", instance);
203 	if (error)
204 		goto fail_irq;
205 
206 	regs->CNTR = CNTR_PDMD | CNTR_INTEN;
207 
208 	error = scsi_add_host(instance, NULL);
209 	if (error)
210 		goto fail_host;
211 
212 	zorro_set_drvdata(z, instance);
213 
214 	scsi_scan_host(instance);
215 	return 0;
216 
217 fail_host:
218 	free_irq(IRQ_AMIGA_PORTS, instance);
219 fail_irq:
220 	scsi_host_put(instance);
221 fail_alloc:
222 	release_mem_region(z->resource.start, 256);
223 	return error;
224 }
225 
226 static void a2091_remove(struct zorro_dev *z)
227 {
228 	struct Scsi_Host *instance = zorro_get_drvdata(z);
229 	struct a2091_hostdata *hdata = shost_priv(instance);
230 
231 	hdata->regs->CNTR = 0;
232 	scsi_remove_host(instance);
233 	free_irq(IRQ_AMIGA_PORTS, instance);
234 	scsi_host_put(instance);
235 	release_mem_region(z->resource.start, 256);
236 }
237 
238 static struct zorro_device_id a2091_zorro_tbl[] = {
239 	{ ZORRO_PROD_CBM_A590_A2091_1 },
240 	{ ZORRO_PROD_CBM_A590_A2091_2 },
241 	{ 0 }
242 };
243 MODULE_DEVICE_TABLE(zorro, a2091_zorro_tbl);
244 
245 static struct zorro_driver a2091_driver = {
246 	.name		= "a2091",
247 	.id_table	= a2091_zorro_tbl,
248 	.probe		= a2091_probe,
249 	.remove		= a2091_remove,
250 };
251 
252 static int __init a2091_init(void)
253 {
254 	return zorro_register_driver(&a2091_driver);
255 }
256 module_init(a2091_init);
257 
258 static void __exit a2091_exit(void)
259 {
260 	zorro_unregister_driver(&a2091_driver);
261 }
262 module_exit(a2091_exit);
263 
264 MODULE_DESCRIPTION("Commodore A2091/A590 SCSI");
265 MODULE_LICENSE("GPL");
266