aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/scsi/sun3x_esp.c
blob: 0621037f027129970748ac77ad918ef0dd6d1442 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
/* sun3x_esp.c: ESP front-end for Sun3x systems.
 *
 * Copyright (C) 2007,2008 Thomas Bogendoerfer (tsbogend@alpha.franken.de)
 */

#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>

#include <asm/sun3x.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <asm/dvma.h>

/* DMA controller reg offsets */
#define DMA_CSR		0x00UL	/* rw  DMA control/status register    0x00   */
#define DMA_ADDR        0x04UL	/* rw  DMA transfer address register  0x04   */
#define DMA_COUNT       0x08UL	/* rw  DMA transfer count register    0x08   */
#define DMA_TEST        0x0cUL	/* rw  DMA test/debug register        0x0c   */

#include <scsi/scsi_host.h>

#include "esp_scsi.h"

#define DRV_MODULE_NAME		"sun3x_esp"
#define PFX DRV_MODULE_NAME	": "
#define DRV_VERSION		"1.000"
#define DRV_MODULE_RELDATE	"Nov 1, 2007"

/*
 * m68k always assumes readl/writel operate on little endian
 * mmio space; this is wrong at least for Sun3x, so we
 * need to workaround this until a proper way is found
 */
#if 0
#define dma_read32(REG) \
	readl(esp->dma_regs + (REG))
#define dma_write32(VAL, REG) \
	writel((VAL), esp->dma_regs + (REG))
#else
#define dma_read32(REG) \
	*(volatile u32 *)(esp->dma_regs + (REG))
#define dma_write32(VAL, REG) \
	do { *(volatile u32 *)(esp->dma_regs + (REG)) = (VAL); } while (0)
#endif

static void sun3x_esp_write8(struct esp *esp, u8 val, unsigned long reg)
{
	writeb(val, esp->regs + (reg * 4UL));
}

static u8 sun3x_esp_read8(struct esp *esp, unsigned long reg)
{
	return readb(esp->regs + (reg * 4UL));
}

static dma_addr_t sun3x_esp_map_single(struct esp *esp, void *buf,
				      size_t sz, int dir)
{
	return dma_map_single(esp->dev, buf, sz, dir);
}

static int sun3x_esp_map_sg(struct esp *esp, struct scatterlist *sg,
				  int num_sg, int dir)
{
	return dma_map_sg(esp->dev, sg, num_sg, dir);
}

static void sun3x_esp_unmap_single(struct esp *esp, dma_addr_t addr,
				  size_t sz, int dir)
{
	dma_unmap_single(esp->dev, addr, sz, dir);
}

static void sun3x_esp_unmap_sg(struct esp *esp, struct scatterlist *sg,
			      int num_sg, int dir)
{
	dma_unmap_sg(esp->dev, sg, num_sg, dir);
}

static int sun3x_esp_irq_pending(struct esp *esp)
{
	if (dma_read32(DMA_CSR) & (DMA_HNDL_INTR | DMA_HNDL_ERROR))
		return 1;
	return 0;
}

static void sun3x_esp_reset_dma(struct esp *esp)
{
	u32 val;

	val = dma_read32(DMA_CSR);
	dma_write32(val | DMA_RST_SCSI, DMA_CSR);
	dma_write32(val & ~DMA_RST_SCSI, DMA_CSR);

	/* Enable interrupts.  */
	val = dma_read32(DMA_CSR);
	dma_write32(val | DMA_INT_ENAB, DMA_CSR);
}

static void sun3x_esp_dma_drain(struct esp *esp)
{
	u32 csr;
	int lim;

	csr = dma_read32(DMA_CSR);
	if (!(csr & DMA_FIFO_ISDRAIN))
		return;

	dma_write32(csr | DMA_FIFO_STDRAIN, DMA_CSR);

	lim = 1000;
	while (dma_read32(DMA_CSR) & DMA_FIFO_ISDRAIN) {
		if (--lim == 0) {
			printk(KERN_ALERT PFX "esp%d: DMA will not drain!\n",
			       esp->host->unique_id);
			break;
		}
		udelay(1);
	}
}

static void sun3x_esp_dma_invalidate(struct esp *esp)
{
	u32 val;
	int lim;

	lim = 1000;
	while ((val = dma_read32(DMA_CSR)) & DMA_PEND_READ) {
		if (--lim == 0) {
			printk(KERN_ALERT PFX "esp%d: DMA will not "
			       "invalidate!\n", esp->host->unique_id);
			break;
		}
		udelay(1);
	}

	val &= ~(DMA_ENABLE | DMA_ST_WRITE | DMA_BCNT_ENAB);
	val |= DMA_FIFO_INV;
	dma_write32(val, DMA_CSR);
	val &= ~DMA_FIFO_INV;
	dma_write32(val, DMA_CSR);
}

static void sun3x_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count,
				  u32 dma_count, int write, u8 cmd)
{
	u32 csr;

	BUG_ON(!(cmd & ESP_CMD_DMA));

	sun3x_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW);
	sun3x_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED);
	csr = dma_read32(DMA_CSR);
	csr |= DMA_ENABLE;
	if (write)
		csr |= DMA_ST_WRITE;
	else
		csr &= ~DMA_ST_WRITE;
	dma_write32(csr, DMA_CSR);
	dma_write32(addr, DMA_ADDR);

	scsi_esp_cmd(esp, cmd);
}

static int sun3x_esp_dma_error(struct esp *esp)
{
	u32 csr = dma_read32(DMA_CSR);

	if (csr & DMA_HNDL_ERROR)
		return 1;

	return 0;
}

static const struct esp_driver_ops sun3x_esp_ops = {
	.esp_write8	=	sun3x_esp_write8,
	.esp_read8	=	sun3x_esp_read8,
	.map_single	=	sun3x_esp_map_single,
	.map_sg		=	sun3x_esp_map_sg,
	.unmap_single	=	sun3x_esp_unmap_single,
	.unmap_sg	=	sun3x_esp_unmap_sg,
	.irq_pending	=	sun3x_esp_irq_pending,
	.reset_dma	=	sun3x_esp_reset_dma,
	.dma_drain	=	sun3x_esp_dma_drain,
	.dma_invalidate	=	sun3x_esp_dma_invalidate,
	.send_dma_cmd	=	sun3x_esp_send_dma_cmd,
	.dma_error	=	sun3x_esp_dma_error,
};

static int __devinit esp_sun3x_probe(struct platform_device *dev)
{
	struct scsi_host_template *tpnt = &scsi_esp_template;
	struct Scsi_Host *host;
	struct esp *esp;
	struct resource *res;
	int err = -ENOMEM;

	host = scsi_host_alloc(tpnt, sizeof(struct esp));
	if (!host)
		goto fail;

	host->max_id = 8;
	esp = shost_priv(host);

	esp->host = host;
	esp->dev = dev;
	esp->ops = &sun3x_esp_ops;

	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
	if (!res || !res->start)
		goto fail_unlink;

	esp->regs = ioremap_nocache(res->start, 0x20);
	if (!esp->regs)
		goto fail_unmap_regs;

	res = platform_get_resource(dev, IORESOURCE_MEM, 1);
	if (!res || !res->start)
		goto fail_unmap_regs;

	esp->dma_regs = ioremap_nocache(res->start, 0x10);

	esp->command_block = dma_alloc_coherent(esp->dev, 16,
						&esp->command_block_dma,
						GFP_KERNEL);
	if (!esp->command_block)
		goto fail_unmap_regs_dma;

	host->irq = platform_get_irq(dev, 0);
	err = request_irq(host->irq, scsi_esp_intr, IRQF_SHARED,
			  "SUN3X ESP", esp);
	if (err < 0)
		goto fail_unmap_command_block;

	esp->scsi_id = 7;
	esp->host->this_id = esp->scsi_id;
	esp->scsi_id_mask = (1 << esp->scsi_id);
	esp->cfreq = 20000000;

	dev_set_drvdata(&dev->dev, esp);

	err = scsi_esp_register(esp, &dev->dev);
	if (err)
		goto fail_free_irq;

	return 0;

fail_free_irq:
	free_irq(host->irq, esp);
fail_unmap_command_block:
	dma_free_coherent(esp->dev, 16,
			  esp->command_block,
			  esp->command_block_dma);
fail_unmap_regs_dma:
	iounmap(esp->dma_regs);
fail_unmap_regs:
	iounmap(esp->regs);
fail_unlink:
	scsi_host_put(host);
fail:
	return err;
}

static int __devexit esp_sun3x_remove(struct platform_device *dev)
{
	struct esp *esp = dev_get_drvdata(&dev->dev);
	unsigned int irq = esp->host->irq;
	u32 val;

	scsi_esp_unregister(esp);

	/* Disable interrupts.  */
	val = dma_read32(DMA_CSR);
	dma_write32(val & ~DMA_INT_ENAB, DMA_CSR);

	free_irq(irq, esp);
	dma_free_coherent(esp->dev, 16,
			  esp->command_block,
			  esp->command_block_dma);

	scsi_host_put(esp->host);

	return 0;
}

static struct platform_driver esp_sun3x_driver = {
	.probe          = esp_sun3x_probe,
	.remove         = __devexit_p(esp_sun3x_remove),
	.driver = {
		.name   = "sun3x_esp",
		.owner	= THIS_MODULE,
	},
};

static int __init sun3x_esp_init(void)
{
	return platform_driver_register(&esp_sun3x_driver);
}

static void __exit sun3x_esp_exit(void)
{
	platform_driver_unregister(&esp_sun3x_driver);
}

MODULE_DESCRIPTION("Sun3x ESP SCSI driver");
MODULE_AUTHOR("Thomas Bogendoerfer (tsbogend@alpha.franken.de)");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);

module_init(sun3x_esp_init);
module_exit(sun3x_esp_exit);
MODULE_ALIAS("platform:sun3x_esp");