pata_cmd640.c revision 276a47a93dbfe5d35261451925020f65cdbfcce8 
1/*
2 * pata_cmd640.c 	- CMD640 PCI PATA for new ATA layer
3 *			  (C) 2007 Red Hat Inc
4 *
5 * Based upon
6 *  linux/drivers/ide/pci/cmd640.c		Version 1.02  Sep 01, 1996
7 *
8 *  Copyright (C) 1995-1996  Linus Torvalds & authors (see driver)
9 *
10 *	This drives only the PCI version of the controller. If you have a
11 *	VLB one then we have enough docs to support it but you can write
12 *	your own code.
13 */
14
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/pci.h>
18#include <linux/init.h>
19#include <linux/blkdev.h>
20#include <linux/delay.h>
21#include <linux/gfp.h>
22#include <scsi/scsi_host.h>
23#include <linux/libata.h>
24
25#define DRV_NAME "pata_cmd640"
26#define DRV_VERSION "0.0.5"
27
28struct cmd640_reg {
29	int last;
30	u8 reg58[ATA_MAX_DEVICES];
31};
32
33enum {
34	CFR = 0x50,
35	CNTRL = 0x51,
36	CMDTIM = 0x52,
37	ARTIM0 = 0x53,
38	DRWTIM0 = 0x54,
39	ARTIM23 = 0x57,
40	DRWTIM23 = 0x58,
41	BRST = 0x59
42};
43
44/**
45 *	cmd640_set_piomode	-	set initial PIO mode data
46 *	@ap: ATA port
47 *	@adev: ATA device
48 *
49 *	Called to do the PIO mode setup.
50 */
51
52static void cmd640_set_piomode(struct ata_port *ap, struct ata_device *adev)
53{
54	struct cmd640_reg *timing = ap->private_data;
55	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
56	struct ata_timing t;
57	const unsigned long T = 1000000 / 33;
58	const u8 setup_data[] = { 0x40, 0x40, 0x40, 0x80, 0x00 };
59	u8 reg;
60	int arttim = ARTIM0 + 2 * adev->devno;
61	struct ata_device *pair = ata_dev_pair(adev);
62
63	if (ata_timing_compute(adev, adev->pio_mode, &t, T, 0) < 0) {
64		printk(KERN_ERR DRV_NAME ": mode computation failed.\n");
65		return;
66	}
67
68	/* The second channel has shared timings and the setup timing is
69	   messy to switch to merge it for worst case */
70	if (ap->port_no && pair) {
71		struct ata_timing p;
72		ata_timing_compute(pair, pair->pio_mode, &p, T, 1);
73		ata_timing_merge(&p, &t, &t, ATA_TIMING_SETUP);
74	}
75
76	/* Make the timings fit */
77	if (t.recover > 16) {
78		t.active += t.recover - 16;
79		t.recover = 16;
80	}
81	if (t.active > 16)
82		t.active = 16;
83
84	/* Now convert the clocks into values we can actually stuff into
85	   the chip */
86
87	if (t.recover > 1)
88		t.recover--;	/* 640B only */
89	else
90		t.recover = 15;
91
92	if (t.setup > 4)
93		t.setup = 0xC0;
94	else
95		t.setup = setup_data[t.setup];
96
97	if (ap->port_no == 0) {
98		t.active &= 0x0F;	/* 0 = 16 */
99
100		/* Load setup timing */
101		pci_read_config_byte(pdev, arttim, &reg);
102		reg &= 0x3F;
103		reg |= t.setup;
104		pci_write_config_byte(pdev, arttim, reg);
105
106		/* Load active/recovery */
107		pci_write_config_byte(pdev, arttim + 1, (t.active << 4) | t.recover);
108	} else {
109		/* Save the shared timings for channel, they will be loaded
110		   by qc_issue. Reloading the setup time is expensive so we
111		   keep a merged one loaded */
112		pci_read_config_byte(pdev, ARTIM23, &reg);
113		reg &= 0x3F;
114		reg |= t.setup;
115		pci_write_config_byte(pdev, ARTIM23, reg);
116		timing->reg58[adev->devno] = (t.active << 4) | t.recover;
117	}
118}
119
120
121/**
122 *	cmd640_qc_issue	-	command preparation hook
123 *	@qc: Command to be issued
124 *
125 *	Channel 1 has shared timings. We must reprogram the
126 *	clock each drive 2/3 switch we do.
127 */
128
129static unsigned int cmd640_qc_issue(struct ata_queued_cmd *qc)
130{
131	struct ata_port *ap = qc->ap;
132	struct ata_device *adev = qc->dev;
133	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
134	struct cmd640_reg *timing = ap->private_data;
135
136	if (ap->port_no != 0 && adev->devno != timing->last) {
137		pci_write_config_byte(pdev, DRWTIM23, timing->reg58[adev->devno]);
138		timing->last = adev->devno;
139	}
140	return ata_sff_qc_issue(qc);
141}
142
143/**
144 *	cmd640_port_start	-	port setup
145 *	@ap: ATA port being set up
146 *
147 *	The CMD640 needs to maintain private data structures so we
148 *	allocate space here.
149 */
150
151static int cmd640_port_start(struct ata_port *ap)
152{
153	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
154	struct cmd640_reg *timing;
155
156	int ret = ata_sff_port_start(ap);
157	if (ret < 0)
158		return ret;
159
160	timing = devm_kzalloc(&pdev->dev, sizeof(struct cmd640_reg), GFP_KERNEL);
161	if (timing == NULL)
162		return -ENOMEM;
163	timing->last = -1;	/* Force a load */
164	ap->private_data = timing;
165	return ret;
166}
167
168static struct scsi_host_template cmd640_sht = {
169	ATA_BMDMA_SHT(DRV_NAME),
170};
171
172static struct ata_port_operations cmd640_port_ops = {
173	.inherits	= &ata_bmdma_port_ops,
174	/* In theory xfer_noirq is not needed once we kill the prefetcher */
175	.sff_data_xfer	= ata_sff_data_xfer_noirq,
176	.qc_issue	= cmd640_qc_issue,
177	.cable_detect	= ata_cable_40wire,
178	.set_piomode	= cmd640_set_piomode,
179	.port_start	= cmd640_port_start,
180};
181
182static void cmd640_hardware_init(struct pci_dev *pdev)
183{
184	u8 ctrl;
185
186	/* CMD640 detected, commiserations */
187	pci_write_config_byte(pdev, 0x5B, 0x00);
188	/* PIO0 command cycles */
189	pci_write_config_byte(pdev, CMDTIM, 0);
190	/* 512 byte bursts (sector) */
191	pci_write_config_byte(pdev, BRST, 0x40);
192	/*
193	 * A reporter a long time ago
194	 * Had problems with the data fifo
195	 * So don't run the risk
196	 * Of putting crap on the disk
197	 * For its better just to go slow
198	 */
199	/* Do channel 0 */
200	pci_read_config_byte(pdev, CNTRL, &ctrl);
201	pci_write_config_byte(pdev, CNTRL, ctrl | 0xC0);
202	/* Ditto for channel 1 */
203	pci_read_config_byte(pdev, ARTIM23, &ctrl);
204	ctrl |= 0x0C;
205	pci_write_config_byte(pdev, ARTIM23, ctrl);
206}
207
208static int cmd640_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
209{
210	static const struct ata_port_info info = {
211		.flags = ATA_FLAG_SLAVE_POSS,
212		.pio_mask = ATA_PIO4,
213		.port_ops = &cmd640_port_ops
214	};
215	const struct ata_port_info *ppi[] = { &info, NULL };
216	int rc;
217
218	rc = pcim_enable_device(pdev);
219	if (rc)
220		return rc;
221
222	cmd640_hardware_init(pdev);
223
224	return ata_pci_sff_init_one(pdev, ppi, &cmd640_sht, NULL, 0);
225}
226
227#ifdef CONFIG_PM
228static int cmd640_reinit_one(struct pci_dev *pdev)
229{
230	struct ata_host *host = dev_get_drvdata(&pdev->dev);
231	int rc;
232
233	rc = ata_pci_device_do_resume(pdev);
234	if (rc)
235		return rc;
236	cmd640_hardware_init(pdev);
237	ata_host_resume(host);
238	return 0;
239}
240#endif
241
242static const struct pci_device_id cmd640[] = {
243	{ PCI_VDEVICE(CMD, 0x640), 0 },
244	{ },
245};
246
247static struct pci_driver cmd640_pci_driver = {
248	.name 		= DRV_NAME,
249	.id_table	= cmd640,
250	.probe 		= cmd640_init_one,
251	.remove		= ata_pci_remove_one,
252#ifdef CONFIG_PM
253	.suspend	= ata_pci_device_suspend,
254	.resume		= cmd640_reinit_one,
255#endif
256};
257
258static int __init cmd640_init(void)
259{
260	return pci_register_driver(&cmd640_pci_driver);
261}
262
263static void __exit cmd640_exit(void)
264{
265	pci_unregister_driver(&cmd640_pci_driver);
266}
267
268MODULE_AUTHOR("Alan Cox");
269MODULE_DESCRIPTION("low-level driver for CMD640 PATA controllers");
270MODULE_LICENSE("GPL");
271MODULE_DEVICE_TABLE(pci, cmd640);
272MODULE_VERSION(DRV_VERSION);
273
274module_init(cmd640_init);
275module_exit(cmd640_exit);
276