1/*
2 * pata_cmd640.c 	- CMD640 PCI PATA for new ATA layer
3 *			  (C) 2007 Red Hat Inc
4 *			  Alan Cox <alan@redhat.com>
5 *
6 * Based upon
7 *  linux/drivers/ide/pci/cmd640.c		Version 1.02  Sep 01, 1996
8 *
9 *  Copyright (C) 1995-1996  Linus Torvalds & authors (see driver)
10 *
11 *	This drives only the PCI version of the controller. If you have a
12 *	VLB one then we have enough docs to support it but you can write
13 *	your own code.
14 */
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/pci.h>
19#include <linux/init.h>
20#include <linux/blkdev.h>
21#include <linux/delay.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_prot. Reloading the setup time is expensive
111		   so we 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_prot	-	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_prot(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_qc_issue_prot(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_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	.module			= THIS_MODULE,
170	.name			= DRV_NAME,
171	.ioctl			= ata_scsi_ioctl,
172	.queuecommand		= ata_scsi_queuecmd,
173	.can_queue		= ATA_DEF_QUEUE,
174	.this_id		= ATA_SHT_THIS_ID,
175	.sg_tablesize		= LIBATA_MAX_PRD,
176	.cmd_per_lun		= ATA_SHT_CMD_PER_LUN,
177	.emulated		= ATA_SHT_EMULATED,
178	.use_clustering		= ATA_SHT_USE_CLUSTERING,
179	.proc_name		= DRV_NAME,
180	.dma_boundary		= ATA_DMA_BOUNDARY,
181	.slave_configure	= ata_scsi_slave_config,
182	.slave_destroy		= ata_scsi_slave_destroy,
183	.bios_param		= ata_std_bios_param,
184};
185
186static struct ata_port_operations cmd640_port_ops = {
187	.port_disable	= ata_port_disable,
188	.set_piomode	= cmd640_set_piomode,
189	.mode_filter	= ata_pci_default_filter,
190	.tf_load	= ata_tf_load,
191	.tf_read	= ata_tf_read,
192	.check_status 	= ata_check_status,
193	.exec_command	= ata_exec_command,
194	.dev_select 	= ata_std_dev_select,
195
196	.freeze		= ata_bmdma_freeze,
197	.thaw		= ata_bmdma_thaw,
198	.error_handler	= ata_bmdma_error_handler,
199	.post_internal_cmd = ata_bmdma_post_internal_cmd,
200	.cable_detect	= ata_cable_40wire,
201
202	.bmdma_setup 	= ata_bmdma_setup,
203	.bmdma_start 	= ata_bmdma_start,
204	.bmdma_stop	= ata_bmdma_stop,
205	.bmdma_status 	= ata_bmdma_status,
206
207	.qc_prep 	= ata_qc_prep,
208	.qc_issue	= cmd640_qc_issue_prot,
209
210	/* In theory this is not needed once we kill the prefetcher */
211	.data_xfer	= ata_data_xfer_noirq,
212
213	.irq_handler	= ata_interrupt,
214	.irq_clear	= ata_bmdma_irq_clear,
215	.irq_on		= ata_irq_on,
216	.irq_ack	= ata_irq_ack,
217
218	.port_start	= cmd640_port_start,
219};
220
221static void cmd640_hardware_init(struct pci_dev *pdev)
222{
223	u8 r;
224	u8 ctrl;
225
226	/* CMD640 detected, commiserations */
227	pci_write_config_byte(pdev, 0x5B, 0x00);
228	/* Get version info */
229	pci_read_config_byte(pdev, CFR, &r);
230	/* PIO0 command cycles */
231	pci_write_config_byte(pdev, CMDTIM, 0);
232	/* 512 byte bursts (sector) */
233	pci_write_config_byte(pdev, BRST, 0x40);
234	/*
235	 * A reporter a long time ago
236	 * Had problems with the data fifo
237	 * So don't run the risk
238	 * Of putting crap on the disk
239	 * For its better just to go slow
240	 */
241	/* Do channel 0 */
242	pci_read_config_byte(pdev, CNTRL, &ctrl);
243	pci_write_config_byte(pdev, CNTRL, ctrl | 0xC0);
244	/* Ditto for channel 1 */
245	pci_read_config_byte(pdev, ARTIM23, &ctrl);
246	ctrl |= 0x0C;
247	pci_write_config_byte(pdev, ARTIM23, ctrl);
248}
249
250static int cmd640_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
251{
252	static const struct ata_port_info info = {
253		.sht = &cmd640_sht,
254		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
255		.pio_mask = 0x1f,
256		.port_ops = &cmd640_port_ops
257	};
258	const struct ata_port_info *ppi[] = { &info, NULL };
259
260	cmd640_hardware_init(pdev);
261	return ata_pci_init_one(pdev, ppi);
262}
263
264static int cmd640_reinit_one(struct pci_dev *pdev)
265{
266	cmd640_hardware_init(pdev);
267#ifdef CONFIG_PM
268	return ata_pci_device_resume(pdev);
269#else
270	return 0;
271#endif
272}
273
274static const struct pci_device_id cmd640[] = {
275	{ PCI_VDEVICE(CMD, 0x640), 0 },
276	{ },
277};
278
279static struct pci_driver cmd640_pci_driver = {
280	.name 		= DRV_NAME,
281	.id_table	= cmd640,
282	.probe 		= cmd640_init_one,
283	.remove		= ata_pci_remove_one,
284#ifdef CONFIG_PM
285	.suspend	= ata_pci_device_suspend,
286#endif
287	.resume		= cmd640_reinit_one,
288};
289
290static int __init cmd640_init(void)
291{
292	return pci_register_driver(&cmd640_pci_driver);
293}
294
295static void __exit cmd640_exit(void)
296{
297	pci_unregister_driver(&cmd640_pci_driver);
298}
299
300MODULE_AUTHOR("Alan Cox");
301MODULE_DESCRIPTION("low-level driver for CMD640 PATA controllers");
302MODULE_LICENSE("GPL");
303MODULE_DEVICE_TABLE(pci, cmd640);
304MODULE_VERSION(DRV_VERSION);
305
306module_init(cmd640_init);
307module_exit(cmd640_exit);
308