xref: /openbmc/linux/drivers/ata/pata_sc1200.c (revision 94cdda6b)
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/blkdev.h>
36 #include <linux/delay.h>
37 #include <scsi/scsi_host.h>
38 #include <linux/libata.h>
39 
40 #define DRV_NAME	"pata_sc1200"
41 #define DRV_VERSION	"0.2.6"
42 
43 #define SC1200_REV_A	0x00
44 #define SC1200_REV_B1	0x01
45 #define SC1200_REV_B3	0x02
46 #define SC1200_REV_C1	0x03
47 #define SC1200_REV_D1	0x04
48 
49 /**
50  *	sc1200_clock	-	PCI clock
51  *
52  *	Return the PCI bus clocking for the SC1200 chipset configuration
53  *	in use. We return 0 for 33MHz 1 for 48MHz and 2 for 66Mhz
54  */
55 
56 static int sc1200_clock(void)
57 {
58 	/* Magic registers that give us the chipset data */
59 	u8 chip_id = inb(0x903C);
60 	u8 silicon_rev = inb(0x903D);
61 	u16 pci_clock;
62 
63 	if (chip_id == 0x04 && silicon_rev < SC1200_REV_B1)
64 		return 0;	/* 33 MHz mode */
65 
66 	/* Clock generator configuration 0x901E its 8/9 are the PCI clocking
67 	   0/3 is 33Mhz 1 is 48 2 is 66 */
68 
69 	pci_clock = inw(0x901E);
70 	pci_clock >>= 8;
71 	pci_clock &= 0x03;
72 	if (pci_clock == 3)
73 		pci_clock = 0;
74 	return pci_clock;
75 }
76 
77 /**
78  *	sc1200_set_piomode		-	PIO setup
79  *	@ap: ATA interface
80  *	@adev: device on the interface
81  *
82  *	Set our PIO requirements. This is fairly simple on the SC1200
83  */
84 
85 static void sc1200_set_piomode(struct ata_port *ap, struct ata_device *adev)
86 {
87 	static const u32 pio_timings[4][5] = {
88 		/* format0, 33Mhz */
89 		{ 0x00009172, 0x00012171, 0x00020080, 0x00032010, 0x00040010 },
90 		/* format1, 33Mhz */
91 		{ 0xd1329172, 0x71212171, 0x30200080, 0x20102010, 0x00100010 },
92 		/* format1, 48Mhz */
93 		{ 0xfaa3f4f3, 0xc23232b2, 0x513101c1, 0x31213121, 0x10211021 },
94 		/* format1, 66Mhz */
95 		{ 0xfff4fff4, 0xf35353d3, 0x814102f1, 0x42314231, 0x11311131 }
96 	};
97 
98 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
99 	u32 format;
100 	unsigned int reg = 0x40 + 0x10 * ap->port_no;
101 	int mode = adev->pio_mode - XFER_PIO_0;
102 
103 	pci_read_config_dword(pdev, reg + 4, &format);
104 	format >>= 31;
105 	format += sc1200_clock();
106 	pci_write_config_dword(pdev, reg + 8 * adev->devno,
107 				pio_timings[format][mode]);
108 }
109 
110 /**
111  *	sc1200_set_dmamode		-	DMA timing setup
112  *	@ap: ATA interface
113  *	@adev: Device being configured
114  *
115  *	We cannot mix MWDMA and UDMA without reloading timings each switch
116  *	master to slave.
117  */
118 
119 static void sc1200_set_dmamode(struct ata_port *ap, struct ata_device *adev)
120 {
121 	static const u32 udma_timing[3][3] = {
122 		{ 0x00921250, 0x00911140, 0x00911030 },
123 		{ 0x00932470, 0x00922260, 0x00922140 },
124 		{ 0x009436A1, 0x00933481, 0x00923261 }
125 	};
126 
127 	static const u32 mwdma_timing[3][3] = {
128 		{ 0x00077771, 0x00012121, 0x00002020 },
129 		{ 0x000BBBB2, 0x00024241, 0x00013131 },
130 		{ 0x000FFFF3, 0x00035352, 0x00015151 }
131 	};
132 
133 	int clock = sc1200_clock();
134 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
135 	unsigned int reg = 0x40 + 0x10 * ap->port_no;
136 	int mode = adev->dma_mode;
137 	u32 format;
138 
139 	if (mode >= XFER_UDMA_0)
140 		format = udma_timing[clock][mode - XFER_UDMA_0];
141 	else
142 		format = mwdma_timing[clock][mode - XFER_MW_DMA_0];
143 
144 	if (adev->devno == 0) {
145 		u32 timings;
146 
147 		pci_read_config_dword(pdev, reg + 4, &timings);
148 		timings &= 0x80000000UL;
149 		timings |= format;
150 		pci_write_config_dword(pdev, reg + 4, timings);
151 	} else
152 		pci_write_config_dword(pdev, reg + 12, format);
153 }
154 
155 /**
156  *	sc1200_qc_issue		-	command issue
157  *	@qc: command pending
158  *
159  *	Called when the libata layer is about to issue a command. We wrap
160  *	this interface so that we can load the correct ATA timings if
161  *	necessary.  Specifically we have a problem that there is only
162  *	one MWDMA/UDMA bit.
163  */
164 
165 static unsigned int sc1200_qc_issue(struct ata_queued_cmd *qc)
166 {
167 	struct ata_port *ap = qc->ap;
168 	struct ata_device *adev = qc->dev;
169 	struct ata_device *prev = ap->private_data;
170 
171 	/* See if the DMA settings could be wrong */
172 	if (ata_dma_enabled(adev) && adev != prev && prev != NULL) {
173 		/* Maybe, but do the channels match MWDMA/UDMA ? */
174 		if ((ata_using_udma(adev) && !ata_using_udma(prev)) ||
175 		    (ata_using_udma(prev) && !ata_using_udma(adev)))
176 		    	/* Switch the mode bits */
177 		    	sc1200_set_dmamode(ap, adev);
178 	}
179 
180 	return ata_bmdma_qc_issue(qc);
181 }
182 
183 /**
184  *	sc1200_qc_defer	-	implement serialization
185  *	@qc: command
186  *
187  *	Serialize command issue on this controller.
188  */
189 
190 static int sc1200_qc_defer(struct ata_queued_cmd *qc)
191 {
192 	struct ata_host *host = qc->ap->host;
193 	struct ata_port *alt = host->ports[1 ^ qc->ap->port_no];
194 	int rc;
195 
196 	/* First apply the usual rules */
197 	rc = ata_std_qc_defer(qc);
198 	if (rc != 0)
199 		return rc;
200 
201 	/* Now apply serialization rules. Only allow a command if the
202 	   other channel state machine is idle */
203 	if (alt && alt->qc_active)
204 		return	ATA_DEFER_PORT;
205 	return 0;
206 }
207 
208 static struct scsi_host_template sc1200_sht = {
209 	ATA_BMDMA_SHT(DRV_NAME),
210 	.sg_tablesize	= LIBATA_DUMB_MAX_PRD,
211 };
212 
213 static struct ata_port_operations sc1200_port_ops = {
214 	.inherits	= &ata_bmdma_port_ops,
215 	.qc_prep 	= ata_bmdma_dumb_qc_prep,
216 	.qc_issue	= sc1200_qc_issue,
217 	.qc_defer	= sc1200_qc_defer,
218 	.cable_detect	= ata_cable_40wire,
219 	.set_piomode	= sc1200_set_piomode,
220 	.set_dmamode	= sc1200_set_dmamode,
221 };
222 
223 /**
224  *	sc1200_init_one		-	Initialise an SC1200
225  *	@dev: PCI device
226  *	@id: Entry in match table
227  *
228  *	Just throw the needed data at the libata helper and it does all
229  *	our work.
230  */
231 
232 static int sc1200_init_one(struct pci_dev *dev, const struct pci_device_id *id)
233 {
234 	static const struct ata_port_info info = {
235 		.flags = ATA_FLAG_SLAVE_POSS,
236 		.pio_mask = ATA_PIO4,
237 		.mwdma_mask = ATA_MWDMA2,
238 		.udma_mask = ATA_UDMA2,
239 		.port_ops = &sc1200_port_ops
240 	};
241 	const struct ata_port_info *ppi[] = { &info, NULL };
242 
243 	return ata_pci_bmdma_init_one(dev, ppi, &sc1200_sht, NULL, 0);
244 }
245 
246 static const struct pci_device_id sc1200[] = {
247 	{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_IDE), },
248 
249 	{ },
250 };
251 
252 static struct pci_driver sc1200_pci_driver = {
253 	.name 		= DRV_NAME,
254 	.id_table	= sc1200,
255 	.probe 		= sc1200_init_one,
256 	.remove		= ata_pci_remove_one,
257 #ifdef CONFIG_PM_SLEEP
258 	.suspend	= ata_pci_device_suspend,
259 	.resume		= ata_pci_device_resume,
260 #endif
261 };
262 
263 module_pci_driver(sc1200_pci_driver);
264 
265 MODULE_AUTHOR("Alan Cox, Mark Lord");
266 MODULE_DESCRIPTION("low-level driver for the NS/AMD SC1200");
267 MODULE_LICENSE("GPL");
268 MODULE_DEVICE_TABLE(pci, sc1200);
269 MODULE_VERSION(DRV_VERSION);
270