GNU Linux-libre 5.10.219-gnu1
[releases.git] / drivers / scsi / a3000.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/types.h>
3 #include <linux/mm.h>
4 #include <linux/ioport.h>
5 #include <linux/init.h>
6 #include <linux/slab.h>
7 #include <linux/spinlock.h>
8 #include <linux/interrupt.h>
9 #include <linux/platform_device.h>
10 #include <linux/module.h>
11
12 #include <asm/page.h>
13 #include <asm/amigaints.h>
14 #include <asm/amigahw.h>
15
16 #include "scsi.h"
17 #include "wd33c93.h"
18 #include "a3000.h"
19
20
21 struct a3000_hostdata {
22         struct WD33C93_hostdata wh;
23         struct a3000_scsiregs *regs;
24 };
25
26 static irqreturn_t a3000_intr(int irq, void *data)
27 {
28         struct Scsi_Host *instance = data;
29         struct a3000_hostdata *hdata = shost_priv(instance);
30         unsigned int status = hdata->regs->ISTR;
31         unsigned long flags;
32
33         if (!(status & ISTR_INT_P))
34                 return IRQ_NONE;
35         if (status & ISTR_INTS) {
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         pr_warn("Non-serviced A3000 SCSI-interrupt? ISTR = %02x\n", status);
42         return IRQ_NONE;
43 }
44
45 static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
46 {
47         struct Scsi_Host *instance = cmd->device->host;
48         struct a3000_hostdata *hdata = shost_priv(instance);
49         struct WD33C93_hostdata *wh = &hdata->wh;
50         struct a3000_scsiregs *regs = hdata->regs;
51         unsigned short cntr = CNTR_PDMD | CNTR_INTEN;
52         unsigned long addr = virt_to_bus(cmd->SCp.ptr);
53
54         /*
55          * if the physical address has the wrong alignment, or if
56          * physical address is bad, or if it is a write and at the
57          * end of a physical memory chunk, then allocate a bounce
58          * buffer
59          */
60         if (addr & A3000_XFER_MASK) {
61                 wh->dma_bounce_len = (cmd->SCp.this_residual + 511) & ~0x1ff;
62                 wh->dma_bounce_buffer = kmalloc(wh->dma_bounce_len,
63                                                 GFP_KERNEL);
64
65                 /* can't allocate memory; use PIO */
66                 if (!wh->dma_bounce_buffer) {
67                         wh->dma_bounce_len = 0;
68                         return 1;
69                 }
70
71                 if (!dir_in) {
72                         /* copy to bounce buffer for a write */
73                         memcpy(wh->dma_bounce_buffer, cmd->SCp.ptr,
74                                cmd->SCp.this_residual);
75                 }
76
77                 addr = virt_to_bus(wh->dma_bounce_buffer);
78         }
79
80         /* setup dma direction */
81         if (!dir_in)
82                 cntr |= CNTR_DDIR;
83
84         /* remember direction */
85         wh->dma_dir = dir_in;
86
87         regs->CNTR = cntr;
88
89         /* setup DMA *physical* address */
90         regs->ACR = addr;
91
92         if (dir_in) {
93                 /* invalidate any cache */
94                 cache_clear(addr, cmd->SCp.this_residual);
95         } else {
96                 /* push any dirty cache */
97                 cache_push(addr, cmd->SCp.this_residual);
98         }
99
100         /* start DMA */
101         mb();                   /* make sure setup is completed */
102         regs->ST_DMA = 1;
103         mb();                   /* make sure DMA has started before next IO */
104
105         /* return success */
106         return 0;
107 }
108
109 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
110                      int status)
111 {
112         struct a3000_hostdata *hdata = shost_priv(instance);
113         struct WD33C93_hostdata *wh = &hdata->wh;
114         struct a3000_scsiregs *regs = hdata->regs;
115
116         /* disable SCSI interrupts */
117         unsigned short cntr = CNTR_PDMD;
118
119         if (!wh->dma_dir)
120                 cntr |= CNTR_DDIR;
121
122         regs->CNTR = cntr;
123         mb();                   /* make sure CNTR is updated before next IO */
124
125         /* flush if we were reading */
126         if (wh->dma_dir) {
127                 regs->FLUSH = 1;
128                 mb();           /* don't allow prefetch */
129                 while (!(regs->ISTR & ISTR_FE_FLG))
130                         barrier();
131                 mb();           /* no IO until FLUSH is done */
132         }
133
134         /* clear a possible interrupt */
135         /* I think that this CINT is only necessary if you are
136          * using the terminal count features.   HM 7 Mar 1994
137          */
138         regs->CINT = 1;
139
140         /* stop DMA */
141         regs->SP_DMA = 1;
142         mb();                   /* make sure DMA is stopped before next IO */
143
144         /* restore the CONTROL bits (minus the direction flag) */
145         regs->CNTR = CNTR_PDMD | CNTR_INTEN;
146         mb();                   /* make sure CNTR is updated before next IO */
147
148         /* copy from a bounce buffer, if necessary */
149         if (status && wh->dma_bounce_buffer) {
150                 if (SCpnt) {
151                         if (wh->dma_dir && SCpnt)
152                                 memcpy(SCpnt->SCp.ptr, wh->dma_bounce_buffer,
153                                        SCpnt->SCp.this_residual);
154                         kfree(wh->dma_bounce_buffer);
155                         wh->dma_bounce_buffer = NULL;
156                         wh->dma_bounce_len = 0;
157                 } else {
158                         kfree(wh->dma_bounce_buffer);
159                         wh->dma_bounce_buffer = NULL;
160                         wh->dma_bounce_len = 0;
161                 }
162         }
163 }
164
165 static struct scsi_host_template amiga_a3000_scsi_template = {
166         .module                 = THIS_MODULE,
167         .name                   = "Amiga 3000 built-in SCSI",
168         .show_info              = wd33c93_show_info,
169         .write_info             = wd33c93_write_info,
170         .proc_name              = "A3000",
171         .queuecommand           = wd33c93_queuecommand,
172         .eh_abort_handler       = wd33c93_abort,
173         .eh_host_reset_handler  = wd33c93_host_reset,
174         .can_queue              = CAN_QUEUE,
175         .this_id                = 7,
176         .sg_tablesize           = SG_ALL,
177         .cmd_per_lun            = CMD_PER_LUN,
178 };
179
180 static int __init amiga_a3000_scsi_probe(struct platform_device *pdev)
181 {
182         struct resource *res;
183         struct Scsi_Host *instance;
184         int error;
185         struct a3000_scsiregs *regs;
186         wd33c93_regs wdregs;
187         struct a3000_hostdata *hdata;
188
189         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
190         if (!res)
191                 return -ENODEV;
192
193         if (!request_mem_region(res->start, resource_size(res), "wd33c93"))
194                 return -EBUSY;
195
196         instance = scsi_host_alloc(&amiga_a3000_scsi_template,
197                                    sizeof(struct a3000_hostdata));
198         if (!instance) {
199                 error = -ENOMEM;
200                 goto fail_alloc;
201         }
202
203         instance->irq = IRQ_AMIGA_PORTS;
204
205         regs = ZTWO_VADDR(res->start);
206         regs->DAWR = DAWR_A3000;
207
208         wdregs.SASR = &regs->SASR;
209         wdregs.SCMD = &regs->SCMD;
210
211         hdata = shost_priv(instance);
212         hdata->wh.no_sync = 0xff;
213         hdata->wh.fast = 0;
214         hdata->wh.dma_mode = CTRL_DMA;
215         hdata->regs = regs;
216
217         wd33c93_init(instance, wdregs, dma_setup, dma_stop, WD33C93_FS_12_15);
218         error = request_irq(IRQ_AMIGA_PORTS, a3000_intr, IRQF_SHARED,
219                             "A3000 SCSI", instance);
220         if (error)
221                 goto fail_irq;
222
223         regs->CNTR = CNTR_PDMD | CNTR_INTEN;
224
225         error = scsi_add_host(instance, NULL);
226         if (error)
227                 goto fail_host;
228
229         platform_set_drvdata(pdev, instance);
230
231         scsi_scan_host(instance);
232         return 0;
233
234 fail_host:
235         free_irq(IRQ_AMIGA_PORTS, instance);
236 fail_irq:
237         scsi_host_put(instance);
238 fail_alloc:
239         release_mem_region(res->start, resource_size(res));
240         return error;
241 }
242
243 static int __exit amiga_a3000_scsi_remove(struct platform_device *pdev)
244 {
245         struct Scsi_Host *instance = platform_get_drvdata(pdev);
246         struct a3000_hostdata *hdata = shost_priv(instance);
247         struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
248
249         hdata->regs->CNTR = 0;
250         scsi_remove_host(instance);
251         free_irq(IRQ_AMIGA_PORTS, instance);
252         scsi_host_put(instance);
253         release_mem_region(res->start, resource_size(res));
254         return 0;
255 }
256
257 static struct platform_driver amiga_a3000_scsi_driver = {
258         .remove = __exit_p(amiga_a3000_scsi_remove),
259         .driver   = {
260                 .name   = "amiga-a3000-scsi",
261         },
262 };
263
264 module_platform_driver_probe(amiga_a3000_scsi_driver, amiga_a3000_scsi_probe);
265
266 MODULE_DESCRIPTION("Amiga 3000 built-in SCSI");
267 MODULE_LICENSE("GPL");
268 MODULE_ALIAS("platform:amiga-a3000-scsi");