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/dma-mapping.h>
11 #include <linux/module.h>
12
13 #include <asm/page.h>
14 #include <asm/amigaints.h>
15 #include <asm/amigahw.h>
16
17 #include <scsi/scsi.h>
18 #include <scsi/scsi_cmnd.h>
19 #include <scsi/scsi_device.h>
20 #include <scsi/scsi_eh.h>
21 #include <scsi/scsi_tcq.h>
22 #include "wd33c93.h"
23 #include "a3000.h"
24
25
26 struct a3000_hostdata {
27 struct WD33C93_hostdata wh;
28 struct a3000_scsiregs *regs;
29 struct device *dev;
30 };
31
32 #define DMA_DIR(d) ((d == DATA_OUT_DIR) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
33
a3000_intr(int irq,void * data)34 static irqreturn_t a3000_intr(int irq, void *data)
35 {
36 struct Scsi_Host *instance = data;
37 struct a3000_hostdata *hdata = shost_priv(instance);
38 unsigned int status = hdata->regs->ISTR;
39 unsigned long flags;
40
41 if (!(status & ISTR_INT_P))
42 return IRQ_NONE;
43 if (status & ISTR_INTS) {
44 spin_lock_irqsave(instance->host_lock, flags);
45 wd33c93_intr(instance);
46 spin_unlock_irqrestore(instance->host_lock, flags);
47 return IRQ_HANDLED;
48 }
49 pr_warn("Non-serviced A3000 SCSI-interrupt? ISTR = %02x\n", status);
50 return IRQ_NONE;
51 }
52
dma_setup(struct scsi_cmnd * cmd,int dir_in)53 static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
54 {
55 struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
56 unsigned long len = scsi_pointer->this_residual;
57 struct Scsi_Host *instance = cmd->device->host;
58 struct a3000_hostdata *hdata = shost_priv(instance);
59 struct WD33C93_hostdata *wh = &hdata->wh;
60 struct a3000_scsiregs *regs = hdata->regs;
61 unsigned short cntr = CNTR_PDMD | CNTR_INTEN;
62 dma_addr_t addr;
63
64 addr = dma_map_single(hdata->dev, scsi_pointer->ptr,
65 len, DMA_DIR(dir_in));
66 if (dma_mapping_error(hdata->dev, addr)) {
67 dev_warn(hdata->dev, "cannot map SCSI data block %p\n",
68 scsi_pointer->ptr);
69 return 1;
70 }
71 scsi_pointer->dma_handle = addr;
72
73 /*
74 * if the physical address has the wrong alignment, or if
75 * physical address is bad, or if it is a write and at the
76 * end of a physical memory chunk, then allocate a bounce
77 * buffer
78 * MSch 20220629 - only wrong alignment tested - bounce
79 * buffer returned by kmalloc is guaranteed to be aligned
80 */
81 if (addr & A3000_XFER_MASK) {
82 WARN_ONCE(1, "Invalid alignment for DMA!");
83 /* drop useless mapping */
84 dma_unmap_single(hdata->dev, scsi_pointer->dma_handle,
85 scsi_pointer->this_residual,
86 DMA_DIR(dir_in));
87
88 wh->dma_bounce_len = (scsi_pointer->this_residual + 511) & ~0x1ff;
89 wh->dma_bounce_buffer = kmalloc(wh->dma_bounce_len,
90 GFP_KERNEL);
91
92 /* can't allocate memory; use PIO */
93 if (!wh->dma_bounce_buffer) {
94 wh->dma_bounce_len = 0;
95 scsi_pointer->dma_handle = (dma_addr_t) NULL;
96 return 1;
97 }
98
99 if (!dir_in) {
100 /* copy to bounce buffer for a write */
101 memcpy(wh->dma_bounce_buffer, scsi_pointer->ptr,
102 scsi_pointer->this_residual);
103 }
104
105 addr = dma_map_single(hdata->dev, scsi_pointer->ptr,
106 len, DMA_DIR(dir_in));
107 if (dma_mapping_error(hdata->dev, addr)) {
108 dev_warn(hdata->dev,
109 "cannot map SCSI data block %p\n",
110 scsi_pointer->ptr);
111 return 1;
112 }
113 scsi_pointer->dma_handle = addr;
114 }
115
116 /* setup dma direction */
117 if (!dir_in)
118 cntr |= CNTR_DDIR;
119
120 /* remember direction */
121 wh->dma_dir = dir_in;
122
123 regs->CNTR = cntr;
124
125 /* setup DMA *physical* address */
126 regs->ACR = addr;
127
128 /* no more cache flush here - dma_map_single() takes care */
129
130 /* start DMA */
131 mb(); /* make sure setup is completed */
132 regs->ST_DMA = 1;
133 mb(); /* make sure DMA has started before next IO */
134
135 /* return success */
136 return 0;
137 }
138
dma_stop(struct Scsi_Host * instance,struct scsi_cmnd * SCpnt,int status)139 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
140 int status)
141 {
142 struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(SCpnt);
143 struct a3000_hostdata *hdata = shost_priv(instance);
144 struct WD33C93_hostdata *wh = &hdata->wh;
145 struct a3000_scsiregs *regs = hdata->regs;
146
147 /* disable SCSI interrupts */
148 unsigned short cntr = CNTR_PDMD;
149
150 if (!wh->dma_dir)
151 cntr |= CNTR_DDIR;
152
153 regs->CNTR = cntr;
154 mb(); /* make sure CNTR is updated before next IO */
155
156 /* flush if we were reading */
157 if (wh->dma_dir) {
158 regs->FLUSH = 1;
159 mb(); /* don't allow prefetch */
160 while (!(regs->ISTR & ISTR_FE_FLG))
161 barrier();
162 mb(); /* no IO until FLUSH is done */
163 }
164
165 /* clear a possible interrupt */
166 /* I think that this CINT is only necessary if you are
167 * using the terminal count features. HM 7 Mar 1994
168 */
169 regs->CINT = 1;
170
171 /* stop DMA */
172 regs->SP_DMA = 1;
173 mb(); /* make sure DMA is stopped before next IO */
174
175 /* restore the CONTROL bits (minus the direction flag) */
176 regs->CNTR = CNTR_PDMD | CNTR_INTEN;
177 mb(); /* make sure CNTR is updated before next IO */
178
179 dma_unmap_single(hdata->dev, scsi_pointer->dma_handle,
180 scsi_pointer->this_residual,
181 DMA_DIR(wh->dma_dir));
182
183 /* copy from a bounce buffer, if necessary */
184 if (status && wh->dma_bounce_buffer) {
185 if (SCpnt) {
186 if (wh->dma_dir && SCpnt)
187 memcpy(scsi_pointer->ptr, wh->dma_bounce_buffer,
188 scsi_pointer->this_residual);
189 kfree(wh->dma_bounce_buffer);
190 wh->dma_bounce_buffer = NULL;
191 wh->dma_bounce_len = 0;
192 } else {
193 kfree(wh->dma_bounce_buffer);
194 wh->dma_bounce_buffer = NULL;
195 wh->dma_bounce_len = 0;
196 }
197 }
198 }
199
200 static const struct scsi_host_template amiga_a3000_scsi_template = {
201 .module = THIS_MODULE,
202 .name = "Amiga 3000 built-in SCSI",
203 .show_info = wd33c93_show_info,
204 .write_info = wd33c93_write_info,
205 .proc_name = "A3000",
206 .queuecommand = wd33c93_queuecommand,
207 .eh_abort_handler = wd33c93_abort,
208 .eh_host_reset_handler = wd33c93_host_reset,
209 .can_queue = CAN_QUEUE,
210 .this_id = 7,
211 .sg_tablesize = SG_ALL,
212 .cmd_per_lun = CMD_PER_LUN,
213 .cmd_size = sizeof(struct scsi_pointer),
214 };
215
amiga_a3000_scsi_probe(struct platform_device * pdev)216 static int __init amiga_a3000_scsi_probe(struct platform_device *pdev)
217 {
218 struct resource *res;
219 struct Scsi_Host *instance;
220 int error;
221 struct a3000_scsiregs *regs;
222 wd33c93_regs wdregs;
223 struct a3000_hostdata *hdata;
224
225 if (dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32))) {
226 dev_warn(&pdev->dev, "cannot use 32 bit DMA\n");
227 return -ENODEV;
228 }
229
230 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
231 if (!res)
232 return -ENODEV;
233
234 if (!request_mem_region(res->start, resource_size(res), "wd33c93"))
235 return -EBUSY;
236
237 instance = scsi_host_alloc(&amiga_a3000_scsi_template,
238 sizeof(struct a3000_hostdata));
239 if (!instance) {
240 error = -ENOMEM;
241 goto fail_alloc;
242 }
243
244 instance->irq = IRQ_AMIGA_PORTS;
245
246 regs = ZTWO_VADDR(res->start);
247 regs->DAWR = DAWR_A3000;
248
249 wdregs.SASR = ®s->SASR;
250 wdregs.SCMD = ®s->SCMD;
251
252 hdata = shost_priv(instance);
253 hdata->dev = &pdev->dev;
254 hdata->wh.no_sync = 0xff;
255 hdata->wh.fast = 0;
256 hdata->wh.dma_mode = CTRL_DMA;
257 hdata->regs = regs;
258
259 wd33c93_init(instance, wdregs, dma_setup, dma_stop, WD33C93_FS_12_15);
260 error = request_irq(IRQ_AMIGA_PORTS, a3000_intr, IRQF_SHARED,
261 "A3000 SCSI", instance);
262 if (error)
263 goto fail_irq;
264
265 regs->CNTR = CNTR_PDMD | CNTR_INTEN;
266
267 error = scsi_add_host(instance, NULL);
268 if (error)
269 goto fail_host;
270
271 platform_set_drvdata(pdev, instance);
272
273 scsi_scan_host(instance);
274 return 0;
275
276 fail_host:
277 free_irq(IRQ_AMIGA_PORTS, instance);
278 fail_irq:
279 scsi_host_put(instance);
280 fail_alloc:
281 release_mem_region(res->start, resource_size(res));
282 return error;
283 }
284
amiga_a3000_scsi_remove(struct platform_device * pdev)285 static void __exit amiga_a3000_scsi_remove(struct platform_device *pdev)
286 {
287 struct Scsi_Host *instance = platform_get_drvdata(pdev);
288 struct a3000_hostdata *hdata = shost_priv(instance);
289 struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
290
291 hdata->regs->CNTR = 0;
292 scsi_remove_host(instance);
293 free_irq(IRQ_AMIGA_PORTS, instance);
294 scsi_host_put(instance);
295 release_mem_region(res->start, resource_size(res));
296 }
297
298 /*
299 * amiga_a3000_scsi_remove() lives in .exit.text. For drivers registered via
300 * module_platform_driver_probe() this is ok because they cannot get unbound at
301 * runtime. So mark the driver struct with __refdata to prevent modpost
302 * triggering a section mismatch warning.
303 */
304 static struct platform_driver amiga_a3000_scsi_driver __refdata = {
305 .remove_new = __exit_p(amiga_a3000_scsi_remove),
306 .driver = {
307 .name = "amiga-a3000-scsi",
308 },
309 };
310
311 module_platform_driver_probe(amiga_a3000_scsi_driver, amiga_a3000_scsi_probe);
312
313 MODULE_DESCRIPTION("Amiga 3000 built-in SCSI");
314 MODULE_LICENSE("GPL");
315 MODULE_ALIAS("platform:amiga-a3000-scsi");
316