xref: /openbmc/linux/drivers/ata/pata_sc1200.c (revision 25985edc)
1 /*
2  * New ATA layer SC1200 driver		Alan Cox <alan@lxorguk.ukuu.org.uk>
3  *
4  * TODO: Mode selection filtering
5  * TODO: Needs custom DMA cleanup code
6  *
7  * Based very heavily on
8  *
9  * linux/drivers/ide/pci/sc1200.c		Version 0.91	28-Jan-2003
10  *
11  * Copyright (C) 2000-2002		Mark Lord <mlord@pobox.com>
12  * May be copied or modified under the terms of the GNU General Public License
13  *
14  * Development of this chipset driver was funded
15  * by the nice folks at National Semiconductor.
16  *
17  * This program is free software; you can redistribute it and/or modify
18  * it under the terms of the GNU General Public License version 2 as
19  * published by the Free Software Foundation.
20  *
21  * This program is distributed in the hope that it will be useful,
22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24  * GNU General Public License for more details.
25  *
26  * You should have received a copy of the GNU General Public License
27  * along with this program; if not, write to the Free Software
28  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
29  *
30  */
31 
32 #include <linux/kernel.h>
33 #include <linux/module.h>
34 #include <linux/pci.h>
35 #include <linux/init.h>
36 #include <linux/blkdev.h>
37 #include <linux/delay.h>
38 #include <scsi/scsi_host.h>
39 #include <linux/libata.h>
40 
41 #define DRV_NAME	"sc1200"
42 #define DRV_VERSION	"0.2.6"
43 
44 #define SC1200_REV_A	0x00
45 #define SC1200_REV_B1	0x01
46 #define SC1200_REV_B3	0x02
47 #define SC1200_REV_C1	0x03
48 #define SC1200_REV_D1	0x04
49 
50 /**
51  *	sc1200_clock	-	PCI clock
52  *
53  *	Return the PCI bus clocking for the SC1200 chipset configuration
54  *	in use. We return 0 for 33MHz 1 for 48MHz and 2 for 66Mhz
55  */
56 
57 static int sc1200_clock(void)
58 {
59 	/* Magic registers that give us the chipset data */
60 	u8 chip_id = inb(0x903C);
61 	u8 silicon_rev = inb(0x903D);
62 	u16 pci_clock;
63 
64 	if (chip_id == 0x04 && silicon_rev < SC1200_REV_B1)
65 		return 0;	/* 33 MHz mode */
66 
67 	/* Clock generator configuration 0x901E its 8/9 are the PCI clocking
68 	   0/3 is 33Mhz 1 is 48 2 is 66 */
69 
70 	pci_clock = inw(0x901E);
71 	pci_clock >>= 8;
72 	pci_clock &= 0x03;
73 	if (pci_clock == 3)
74 		pci_clock = 0;
75 	return pci_clock;
76 }
77 
78 /**
79  *	sc1200_set_piomode		-	PIO setup
80  *	@ap: ATA interface
81  *	@adev: device on the interface
82  *
83  *	Set our PIO requirements. This is fairly simple on the SC1200
84  */
85 
86 static void sc1200_set_piomode(struct ata_port *ap, struct ata_device *adev)
87 {
88 	static const u32 pio_timings[4][5] = {
89 		{0x00009172, 0x00012171, 0x00020080, 0x00032010, 0x00040010},	// format0  33Mhz
90 		{0xd1329172, 0x71212171, 0x30200080, 0x20102010, 0x00100010},	// format1, 33Mhz
91 		{0xfaa3f4f3, 0xc23232b2, 0x513101c1, 0x31213121, 0x10211021},	// format1, 48Mhz
92 		{0xfff4fff4, 0xf35353d3, 0x814102f1, 0x42314231, 0x11311131}	// format1, 66Mhz
93 	};
94 
95 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
96 	u32 format;
97 	unsigned int reg = 0x40 + 0x10 * ap->port_no;
98 	int mode = adev->pio_mode - XFER_PIO_0;
99 
100 	pci_read_config_dword(pdev, reg + 4, &format);
101 	format >>= 31;
102 	format += sc1200_clock();
103 	pci_write_config_dword(pdev, reg + 8 * adev->devno,
104 				pio_timings[format][mode]);
105 }
106 
107 /**
108  *	sc1200_set_dmamode		-	DMA timing setup
109  *	@ap: ATA interface
110  *	@adev: Device being configured
111  *
112  *	We cannot mix MWDMA and UDMA without reloading timings each switch
113  *	master to slave.
114  */
115 
116 static void sc1200_set_dmamode(struct ata_port *ap, struct ata_device *adev)
117 {
118 	static const u32 udma_timing[3][3] = {
119 		{ 0x00921250, 0x00911140, 0x00911030 },
120 		{ 0x00932470, 0x00922260, 0x00922140 },
121 		{ 0x009436A1, 0x00933481, 0x00923261 }
122 	};
123 
124 	static const u32 mwdma_timing[3][3] = {
125 		{ 0x00077771, 0x00012121, 0x00002020 },
126 		{ 0x000BBBB2, 0x00024241, 0x00013131 },
127 		{ 0x000FFFF3, 0x00035352, 0x00015151 }
128 	};
129 
130 	int clock = sc1200_clock();
131 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
132 	unsigned int reg = 0x40 + 0x10 * ap->port_no;
133 	int mode = adev->dma_mode;
134 	u32 format;
135 
136 	if (mode >= XFER_UDMA_0)
137 		format = udma_timing[clock][mode - XFER_UDMA_0];
138 	else
139 		format = mwdma_timing[clock][mode - XFER_MW_DMA_0];
140 
141 	if (adev->devno == 0) {
142 		u32 timings;
143 
144 		pci_read_config_dword(pdev, reg + 4, &timings);
145 		timings &= 0x80000000UL;
146 		timings |= format;
147 		pci_write_config_dword(pdev, reg + 4, timings);
148 	} else
149 		pci_write_config_dword(pdev, reg + 12, format);
150 }
151 
152 /**
153  *	sc1200_qc_issue		-	command issue
154  *	@qc: command pending
155  *
156  *	Called when the libata layer is about to issue a command. We wrap
157  *	this interface so that we can load the correct ATA timings if
158  *	necessary.  Specifically we have a problem that there is only
159  *	one MWDMA/UDMA bit.
160  */
161 
162 static unsigned int sc1200_qc_issue(struct ata_queued_cmd *qc)
163 {
164 	struct ata_port *ap = qc->ap;
165 	struct ata_device *adev = qc->dev;
166 	struct ata_device *prev = ap->private_data;
167 
168 	/* See if the DMA settings could be wrong */
169 	if (ata_dma_enabled(adev) && adev != prev && prev != NULL) {
170 		/* Maybe, but do the channels match MWDMA/UDMA ? */
171 		if ((ata_using_udma(adev) && !ata_using_udma(prev)) ||
172 		    (ata_using_udma(prev) && !ata_using_udma(adev)))
173 		    	/* Switch the mode bits */
174 		    	sc1200_set_dmamode(ap, adev);
175 	}
176 
177 	return ata_bmdma_qc_issue(qc);
178 }
179 
180 /**
181  *	sc1200_qc_defer	-	implement serialization
182  *	@qc: command
183  *
184  *	Serialize command issue on this controller.
185  */
186 
187 static int sc1200_qc_defer(struct ata_queued_cmd *qc)
188 {
189 	struct ata_host *host = qc->ap->host;
190 	struct ata_port *alt = host->ports[1 ^ qc->ap->port_no];
191 	int rc;
192 
193 	/* First apply the usual rules */
194 	rc = ata_std_qc_defer(qc);
195 	if (rc != 0)
196 		return rc;
197 
198 	/* Now apply serialization rules. Only allow a command if the
199 	   other channel state machine is idle */
200 	if (alt && alt->qc_active)
201 		return	ATA_DEFER_PORT;
202 	return 0;
203 }
204 
205 static struct scsi_host_template sc1200_sht = {
206 	ATA_BMDMA_SHT(DRV_NAME),
207 	.sg_tablesize	= LIBATA_DUMB_MAX_PRD,
208 };
209 
210 static struct ata_port_operations sc1200_port_ops = {
211 	.inherits	= &ata_bmdma_port_ops,
212 	.qc_prep 	= ata_bmdma_dumb_qc_prep,
213 	.qc_issue	= sc1200_qc_issue,
214 	.qc_defer	= sc1200_qc_defer,
215 	.cable_detect	= ata_cable_40wire,
216 	.set_piomode	= sc1200_set_piomode,
217 	.set_dmamode	= sc1200_set_dmamode,
218 };
219 
220 /**
221  *	sc1200_init_one		-	Initialise an SC1200
222  *	@dev: PCI device
223  *	@id: Entry in match table
224  *
225  *	Just throw the needed data at the libata helper and it does all
226  *	our work.
227  */
228 
229 static int sc1200_init_one(struct pci_dev *dev, const struct pci_device_id *id)
230 {
231 	static const struct ata_port_info info = {
232 		.flags = ATA_FLAG_SLAVE_POSS,
233 		.pio_mask = ATA_PIO4,
234 		.mwdma_mask = ATA_MWDMA2,
235 		.udma_mask = ATA_UDMA2,
236 		.port_ops = &sc1200_port_ops
237 	};
238 	const struct ata_port_info *ppi[] = { &info, NULL };
239 
240 	return ata_pci_bmdma_init_one(dev, ppi, &sc1200_sht, NULL, 0);
241 }
242 
243 static const struct pci_device_id sc1200[] = {
244 	{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_IDE), },
245 
246 	{ },
247 };
248 
249 static struct pci_driver sc1200_pci_driver = {
250 	.name 		= DRV_NAME,
251 	.id_table	= sc1200,
252 	.probe 		= sc1200_init_one,
253 	.remove		= ata_pci_remove_one,
254 #ifdef CONFIG_PM
255 	.suspend	= ata_pci_device_suspend,
256 	.resume		= ata_pci_device_resume,
257 #endif
258 };
259 
260 static int __init sc1200_init(void)
261 {
262 	return pci_register_driver(&sc1200_pci_driver);
263 }
264 
265 static void __exit sc1200_exit(void)
266 {
267 	pci_unregister_driver(&sc1200_pci_driver);
268 }
269 
270 MODULE_AUTHOR("Alan Cox, Mark Lord");
271 MODULE_DESCRIPTION("low-level driver for the NS/AMD SC1200");
272 MODULE_LICENSE("GPL");
273 MODULE_DEVICE_TABLE(pci, sc1200);
274 MODULE_VERSION(DRV_VERSION);
275 
276 module_init(sc1200_init);
277 module_exit(sc1200_exit);
278