summaryrefslogtreecommitdiffstats
path: root/drivers/ata/pata_sl82c105.c
blob: 98548f640c8eae74bc408b67273f529dd9b8a310 (plain) (blame)
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
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
/*
 * pata_sl82c105.c 	- SL82C105 PATA for new ATA layer
 *			  (C) 2005 Red Hat Inc
 *
 * Based in part on linux/drivers/ide/pci/sl82c105.c
 * 		SL82C105/Winbond 553 IDE driver
 *
 * and in part on the documentation and errata sheet
 *
 *
 * Note: The controller like many controllers has shared timings for
 * PIO and DMA. We thus flip to the DMA timings in dma_start and flip back
 * in the dma_stop function. Thus we actually don't need a set_dmamode
 * method as the PIO method is always called and will set the right PIO
 * timing parameters.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>

#define DRV_NAME "pata_sl82c105"
#define DRV_VERSION "0.3.3"

enum {
	/*
	 * SL82C105 PCI config register 0x40 bits.
	 */
	CTRL_IDE_IRQB	=	(1 << 30),
	CTRL_IDE_IRQA   =	(1 << 28),
	CTRL_LEGIRQ     =	(1 << 11),
	CTRL_P1F16      =	(1 << 5),
	CTRL_P1EN       =	(1 << 4),
	CTRL_P0F16      =	(1 << 1),
	CTRL_P0EN       =	(1 << 0)
};

/**
 *	sl82c105_pre_reset		-	probe begin
 *	@link: ATA link
 *	@deadline: deadline jiffies for the operation
 *
 *	Set up cable type and use generic probe init
 */

static int sl82c105_pre_reset(struct ata_link *link, unsigned long deadline)
{
	static const struct pci_bits sl82c105_enable_bits[] = {
		{ 0x40, 1, 0x01, 0x01 },
		{ 0x40, 1, 0x10, 0x10 }
	};
	struct ata_port *ap = link->ap;
	struct pci_dev *pdev = to_pci_dev(ap->host->dev);

	if (ap->port_no && !pci_test_config_bits(pdev, &sl82c105_enable_bits[ap->port_no]))
		return -ENOENT;
	return ata_sff_prereset(link, deadline);
}


/**
 *	sl82c105_configure_piomode	-	set chip PIO timing
 *	@ap: ATA interface
 *	@adev: ATA device
 *	@pio: PIO mode
 *
 *	Called to do the PIO mode setup. Our timing registers are shared
 *	so a configure_dmamode call will undo any work we do here and vice
 *	versa
 */

static void sl82c105_configure_piomode(struct ata_port *ap, struct ata_device *adev, int pio)
{
	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
	static u16 pio_timing[5] = {
		0x50D, 0x407, 0x304, 0x242, 0x240
	};
	u16 dummy;
	int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);

	pci_write_config_word(pdev, timing, pio_timing[pio]);
	/* Can we lose this oddity of the old driver */
	pci_read_config_word(pdev, timing, &dummy);
}

/**
 *	sl82c105_set_piomode	-	set initial PIO mode data
 *	@ap: ATA interface
 *	@adev: ATA device
 *
 *	Called to do the PIO mode setup. Our timing registers are shared
 *	but we want to set the PIO timing by default.
 */

static void sl82c105_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
	sl82c105_configure_piomode(ap, adev, adev->pio_mode - XFER_PIO_0);
}

/**
 *	sl82c105_configure_dmamode	-	set DMA mode in chip
 *	@ap: ATA interface
 *	@adev: ATA device
 *
 *	Load DMA cycle times into the chip ready for a DMA transfer
 *	to occur.
 */

static void sl82c105_configure_dmamode(struct ata_port *ap, struct ata_device *adev)
{
	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
	static u16 dma_timing[3] = {
		0x707, 0x201, 0x200
	};
	u16 dummy;
	int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);
	int dma = adev->dma_mode - XFER_MW_DMA_0;

	pci_write_config_word(pdev, timing, dma_timing[dma]);
	/* Can we lose this oddity of the old driver */
	pci_read_config_word(pdev, timing, &dummy);
}

/**
 *	sl82c105_reset_engine	-	Reset the DMA engine
 *	@ap: ATA interface
 *
 *	The sl82c105 has some serious problems with the DMA engine
 *	when transfers don't run as expected or ATAPI is used. The
 *	recommended fix is to reset the engine each use using a chip
 *	test register.
 */

static void sl82c105_reset_engine(struct ata_port *ap)
{
	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
	u16 val;

	pci_read_config_word(pdev, 0x7E, &val);
	pci_write_config_word(pdev, 0x7E, val | 4);
	pci_write_config_word(pdev, 0x7E, val & ~4);
}

/**
 *	sl82c105_bmdma_start		-	DMA engine begin
 *	@qc: ATA command
 *
 *	Reset the DMA engine each use as recommended by the errata
 *	document.
 *
 *	FIXME: if we switch clock at BMDMA start/end we might get better
 *	PIO performance on DMA capable devices.
 */

static void sl82c105_bmdma_start(struct ata_queued_cmd *qc)
{
	struct ata_port *ap = qc->ap;

	udelay(100);
	sl82c105_reset_engine(ap);
	udelay(100);

	/* Set the clocks for DMA */
	sl82c105_configure_dmamode(ap, qc->dev);
	/* Activate DMA */
	ata_bmdma_start(qc);
}

/**
 *	sl82c105_bmdma_end		-	DMA engine stop
 *	@qc: ATA command
 *
 *	Reset the DMA engine each use as recommended by the errata
 *	document.
 *
 *	This function is also called to turn off DMA when a timeout occurs
 *	during DMA operation. In both cases we need to reset the engine,
 *	so no actual eng_timeout handler is required.
 *
 *	We assume bmdma_stop is always called if bmdma_start as called. If
 *	not then we may need to wrap qc_issue.
 */

static void sl82c105_bmdma_stop(struct ata_queued_cmd *qc)
{
	struct ata_port *ap = qc->ap;

	ata_bmdma_stop(qc);
	sl82c105_reset_engine(ap);
	udelay(100);

	/* This will redo the initial setup of the DMA device to matching
	   PIO timings */
	sl82c105_set_piomode(ap, qc->dev);
}

/**
 *	sl82c105_qc_defer	-	implement serialization
 *	@qc: command
 *
 *	We must issue one command per host not per channel because
 *	of the reset bug.
 *
 *	Q: is the scsi host lock sufficient ?
 */

static int sl82c105_qc_defer(struct ata_queued_cmd *qc)
{
	struct ata_host *host = qc->ap->host;
	struct ata_port *alt = host->ports[1 ^ qc->ap->port_no];
	int rc;

	/* First apply the usual rules */
	rc = ata_std_qc_defer(qc);
	if (rc != 0)
		return rc;

	/* Now apply serialization rules. Only allow a command if the
	   other channel state machine is idle */
	if (alt && alt->qc_active)
		return	ATA_DEFER_PORT;
	return 0;
}

static struct scsi_host_template sl82c105_sht = {
	ATA_BMDMA_SHT(DRV_NAME),
};

static struct ata_port_operations sl82c105_port_ops = {
	.inherits	= &ata_bmdma_port_ops,
	.qc_defer	= sl82c105_qc_defer,
	.bmdma_start 	= sl82c105_bmdma_start,
	.bmdma_stop	= sl82c105_bmdma_stop,
	.cable_detect	= ata_cable_40wire,
	.set_piomode	= sl82c105_set_piomode,
	.prereset	= sl82c105_pre_reset,
};

/**
 *	sl82c105_bridge_revision	-	find bridge version
 *	@pdev: PCI device for the ATA function
 *
 *	Locates the PCI bridge associated with the ATA function and
 *	providing it is a Winbond 553 reports the revision. If it cannot
 *	find a revision or the right device it returns -1
 */

static int sl82c105_bridge_revision(struct pci_dev *pdev)
{
	struct pci_dev *bridge;

	/*
	 * The bridge should be part of the same device, but function 0.
	 */
	bridge = pci_get_slot(pdev->bus,
			       PCI_DEVFN(PCI_SLOT(pdev->devfn), 0));
	if (!bridge)
		return -1;

	/*
	 * Make sure it is a Winbond 553 and is an ISA bridge.
	 */
	if (bridge->vendor != PCI_VENDOR_ID_WINBOND ||
	    bridge->device != PCI_DEVICE_ID_WINBOND_83C553 ||
	    bridge->class >> 8 != PCI_CLASS_BRIDGE_ISA) {
	    	pci_dev_put(bridge);
		return -1;
	}
	/*
	 * We need to find function 0's revision, not function 1
	 */
	pci_dev_put(bridge);
	return bridge->revision;
}


static int sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id)
{
	static const struct ata_port_info info_dma = {
		.flags = ATA_FLAG_SLAVE_POSS,
		.pio_mask = ATA_PIO4,
		.mwdma_mask = ATA_MWDMA2,
		.port_ops = &sl82c105_port_ops
	};
	static const struct ata_port_info info_early = {
		.flags = ATA_FLAG_SLAVE_POSS,
		.pio_mask = ATA_PIO4,
		.port_ops = &sl82c105_port_ops
	};
	/* for now use only the first port */
	const struct ata_port_info *ppi[] = { &info_early,
					       NULL };
	u32 val;
	int rev;
	int rc;

	rc = pcim_enable_device(dev);
	if (rc)
		return rc;

	rev = sl82c105_bridge_revision(dev);

	if (rev == -1)
		dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Unable to find bridge, disabling DMA.\n");
	else if (rev <= 5)
		dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Early bridge revision, no DMA available.\n");
	else
		ppi[0] = &info_dma;

	pci_read_config_dword(dev, 0x40, &val);
	val |= CTRL_P0EN | CTRL_P0F16 | CTRL_P1F16;
	pci_write_config_dword(dev, 0x40, val);

	return ata_pci_bmdma_init_one(dev, ppi, &sl82c105_sht, NULL, 0);
}

static const struct pci_device_id sl82c105[] = {
	{ PCI_VDEVICE(WINBOND, PCI_DEVICE_ID_WINBOND_82C105), },

	{ },
};

static struct pci_driver sl82c105_pci_driver = {
	.name 		= DRV_NAME,
	.id_table	= sl82c105,
	.probe 		= sl82c105_init_one,
	.remove		= ata_pci_remove_one
};

static int __init sl82c105_init(void)
{
	return pci_register_driver(&sl82c105_pci_driver);
}

static void __exit sl82c105_exit(void)
{
	pci_unregister_driver(&sl82c105_pci_driver);
}

MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("low-level driver for Sl82c105");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, sl82c105);
MODULE_VERSION(DRV_VERSION);

module_init(sl82c105_init);
module_exit(sl82c105_exit);