summaryrefslogtreecommitdiffstats
path: root/drivers/ata/pata_at91.c
blob: 0da0dcc7dd089427a988171c3f1a8b62c1b8f90f (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
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
353
354
355
356
357
358
/*
 * PATA driver for AT91SAM9260 Static Memory Controller
 * with CompactFlash interface in True IDE mode
 *
 * Copyright (C) 2009 Matyukevich Sergey
 *
 * Based on:
 *      * generic platform driver by Paul Mundt: drivers/ata/pata_platform.c
 *      * pata_at32 driver by Kristoffer Nyborg Gregertsen
 *      * at91_ide driver by Stanislaw Gruszka
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/gfp.h>
#include <scsi/scsi_host.h>
#include <linux/ata.h>
#include <linux/clk.h>
#include <linux/libata.h>
#include <linux/platform_device.h>
#include <linux/ata_platform.h>

#include <mach/at91sam9_smc.h>
#include <mach/board.h>
#include <mach/gpio.h>


#define DRV_NAME "pata_at91"
#define DRV_VERSION "0.1"

#define CF_IDE_OFFSET	    0x00c00000
#define CF_ALT_IDE_OFFSET   0x00e00000
#define CF_IDE_RES_SIZE     0x08

struct at91_ide_info {
	unsigned long mode;
	unsigned int cs;

	struct clk *mck;

	void __iomem *ide_addr;
	void __iomem *alt_addr;
};

static const struct ata_timing initial_timing =
	{XFER_PIO_0, 70, 290, 240, 600, 165, 150, 600, 0};

static unsigned long calc_mck_cycles(unsigned long ns, unsigned long mck_hz)
{
	unsigned long mul;

	/*
	* cycles = x [nsec] * f [Hz] / 10^9 [ns in sec] =
	*     x * (f / 1_000_000_000) =
	*     x * ((f * 65536) / 1_000_000_000) / 65536 =
	*     x * (((f / 10_000) * 65536) / 100_000) / 65536 =
	*/

	mul = (mck_hz / 10000) << 16;
	mul /= 100000;

	return (ns * mul + 65536) >> 16;    /* rounding */
}

static void set_smc_mode(struct at91_ide_info *info)
{
	at91_sys_write(AT91_SMC_MODE(info->cs), info->mode);
	return;
}

static void set_smc_timing(struct device *dev,
		struct at91_ide_info *info, const struct ata_timing *ata)
{
	unsigned long read_cycle, write_cycle, active, recover;
	unsigned long nrd_setup, nrd_pulse, nrd_recover;
	unsigned long nwe_setup, nwe_pulse;

	unsigned long ncs_write_setup, ncs_write_pulse;
	unsigned long ncs_read_setup, ncs_read_pulse;

	unsigned long mck_hz;

	read_cycle  = ata->cyc8b;
	nrd_setup   = ata->setup;
	nrd_pulse   = ata->act8b;
	nrd_recover = ata->rec8b;

	mck_hz = clk_get_rate(info->mck);

	read_cycle  = calc_mck_cycles(read_cycle, mck_hz);
	nrd_setup   = calc_mck_cycles(nrd_setup, mck_hz);
	nrd_pulse   = calc_mck_cycles(nrd_pulse, mck_hz);
	nrd_recover = calc_mck_cycles(nrd_recover, mck_hz);

	active  = nrd_setup + nrd_pulse;
	recover = read_cycle - active;

	/* Need at least two cycles recovery */
	if (recover < 2)
		read_cycle = active + 2;

	/* (CS0, CS1, DIR, OE) <= (CFCE1, CFCE2, CFRNW, NCSX) timings */
	ncs_read_setup = 1;
	ncs_read_pulse = read_cycle - 2;

	/* Write timings same as read timings */
	write_cycle = read_cycle;
	nwe_setup = nrd_setup;
	nwe_pulse = nrd_pulse;
	ncs_write_setup = ncs_read_setup;
	ncs_write_pulse = ncs_read_pulse;

	dev_dbg(dev, "ATA timings: nrd_setup = %lu nrd_pulse = %lu nrd_cycle = %lu\n",
			nrd_setup, nrd_pulse, read_cycle);
	dev_dbg(dev, "ATA timings: nwe_setup = %lu nwe_pulse = %lu nwe_cycle = %lu\n",
			nwe_setup, nwe_pulse, write_cycle);
	dev_dbg(dev, "ATA timings: ncs_read_setup = %lu ncs_read_pulse = %lu\n",
			ncs_read_setup, ncs_read_pulse);
	dev_dbg(dev, "ATA timings: ncs_write_setup = %lu ncs_write_pulse = %lu\n",
			ncs_write_setup, ncs_write_pulse);

	at91_sys_write(AT91_SMC_SETUP(info->cs),
			AT91_SMC_NWESETUP_(nwe_setup) |
			AT91_SMC_NRDSETUP_(nrd_setup) |
			AT91_SMC_NCS_WRSETUP_(ncs_write_setup) |
			AT91_SMC_NCS_RDSETUP_(ncs_read_setup));

	at91_sys_write(AT91_SMC_PULSE(info->cs),
			AT91_SMC_NWEPULSE_(nwe_pulse) |
			AT91_SMC_NRDPULSE_(nrd_pulse) |
			AT91_SMC_NCS_WRPULSE_(ncs_write_pulse) |
			AT91_SMC_NCS_RDPULSE_(ncs_read_pulse));

	at91_sys_write(AT91_SMC_CYCLE(info->cs),
			AT91_SMC_NWECYCLE_(write_cycle) |
			AT91_SMC_NRDCYCLE_(read_cycle));

	return;
}

static void pata_at91_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
	struct at91_ide_info *info = ap->host->private_data;
	struct ata_timing timing;
	int ret;

	/* Compute ATA timing and set it to SMC */
	ret = ata_timing_compute(adev, adev->pio_mode, &timing, 1000, 0);
	if (ret) {
		dev_warn(ap->dev, "Failed to compute ATA timing %d, "
			 "set PIO_0 timing\n", ret);
		set_smc_timing(ap->dev, info, &initial_timing);
	} else {
		set_smc_timing(ap->dev, info, &timing);
	}

	/* Setup SMC mode */
	set_smc_mode(info);

	return;
}

static unsigned int pata_at91_data_xfer_noirq(struct ata_device *dev,
		unsigned char *buf, unsigned int buflen, int rw)
{
	struct at91_ide_info *info = dev->link->ap->host->private_data;
	unsigned int consumed;
	unsigned long flags;
	unsigned int mode;

	local_irq_save(flags);
	mode = at91_sys_read(AT91_SMC_MODE(info->cs));

	/* set 16bit mode before writing data */
	at91_sys_write(AT91_SMC_MODE(info->cs),
			(mode & ~AT91_SMC_DBW) | AT91_SMC_DBW_16);

	consumed = ata_sff_data_xfer(dev, buf, buflen, rw);

	/* restore 8bit mode after data is written */
	at91_sys_write(AT91_SMC_MODE(info->cs),
			(mode & ~AT91_SMC_DBW) | AT91_SMC_DBW_8);

	local_irq_restore(flags);
	return consumed;
}

static struct scsi_host_template pata_at91_sht = {
	ATA_PIO_SHT(DRV_NAME),
};

static struct ata_port_operations pata_at91_port_ops = {
	.inherits	= &ata_sff_port_ops,

	.sff_data_xfer	= pata_at91_data_xfer_noirq,
	.set_piomode	= pata_at91_set_piomode,
	.cable_detect	= ata_cable_40wire,
};

static int __devinit pata_at91_probe(struct platform_device *pdev)
{
	struct at91_cf_data *board = pdev->dev.platform_data;
	struct device *dev = &pdev->dev;
	struct at91_ide_info *info;
	struct resource *mem_res;
	struct ata_host *host;
	struct ata_port *ap;

	int irq_flags = 0;
	int irq = 0;
	int ret;

	/*  get platform resources: IO/CTL memories and irq/rst pins */

	if (pdev->num_resources != 1) {
		dev_err(&pdev->dev, "invalid number of resources\n");
		return -EINVAL;
	}

	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	if (!mem_res) {
		dev_err(dev, "failed to get mem resource\n");
		return -EINVAL;
	}

	irq = board->irq_pin;

	/* init ata host */

	host = ata_host_alloc(dev, 1);

	if (!host)
		return -ENOMEM;

	ap = host->ports[0];
	ap->ops = &pata_at91_port_ops;
	ap->flags |= ATA_FLAG_SLAVE_POSS;
	ap->pio_mask = ATA_PIO4;

	if (!irq) {
		ap->flags |= ATA_FLAG_PIO_POLLING;
		ata_port_desc(ap, "no IRQ, using PIO polling");
	}

	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);

	if (!info) {
		dev_err(dev, "failed to allocate memory for private data\n");
		return -ENOMEM;
	}

	info->mck = clk_get(NULL, "mck");

	if (IS_ERR(info->mck)) {
		dev_err(dev, "failed to get access to mck clock\n");
		return -ENODEV;
	}

	info->cs    = board->chipselect;
	info->mode  = AT91_SMC_READMODE | AT91_SMC_WRITEMODE |
		AT91_SMC_EXNWMODE_READY | AT91_SMC_BAT_SELECT |
		AT91_SMC_DBW_8 | AT91_SMC_TDF_(0);

	info->ide_addr = devm_ioremap(dev,
			mem_res->start + CF_IDE_OFFSET, CF_IDE_RES_SIZE);

	if (!info->ide_addr) {
		dev_err(dev, "failed to map IO base\n");
		ret = -ENOMEM;
		goto err_put;
	}

	info->alt_addr = devm_ioremap(dev,
			mem_res->start + CF_ALT_IDE_OFFSET, CF_IDE_RES_SIZE);

	if (!info->alt_addr) {
		dev_err(dev, "failed to map CTL base\n");
		ret = -ENOMEM;
		goto err_put;
	}

	ap->ioaddr.cmd_addr = info->ide_addr;
	ap->ioaddr.ctl_addr = info->alt_addr + 0x06;
	ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr;

	ata_sff_std_ports(&ap->ioaddr);

	ata_port_desc(ap, "mmio cmd 0x%llx ctl 0x%llx",
			(unsigned long long)mem_res->start + CF_IDE_OFFSET,
			(unsigned long long)mem_res->start + CF_ALT_IDE_OFFSET);

	host->private_data = info;

	return ata_host_activate(host, irq ? gpio_to_irq(irq) : 0,
			irq ? ata_sff_interrupt : NULL,
			irq_flags, &pata_at91_sht);

err_put:
	clk_put(info->mck);
	return ret;
}

static int __devexit pata_at91_remove(struct platform_device *pdev)
{
	struct ata_host *host = dev_get_drvdata(&pdev->dev);
	struct at91_ide_info *info;

	if (!host)
		return 0;
	info = host->private_data;

	ata_host_detach(host);

	if (!info)
		return 0;

	clk_put(info->mck);

	return 0;
}

static struct platform_driver pata_at91_driver = {
	.probe		= pata_at91_probe,
	.remove		= __devexit_p(pata_at91_remove),
	.driver 	= {
		.name		= DRV_NAME,
		.owner		= THIS_MODULE,
	},
};

static int __init pata_at91_init(void)
{
	return platform_driver_register(&pata_at91_driver);
}

static void __exit pata_at91_exit(void)
{
	platform_driver_unregister(&pata_at91_driver);
}


module_init(pata_at91_init);
module_exit(pata_at91_exit);


MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Driver for CF in True IDE mode on AT91SAM9260 SoC");
MODULE_AUTHOR("Matyukevich Sergey");
MODULE_VERSION(DRV_VERSION);

OpenPOWER on IntegriCloud