xref: /openbmc/linux/drivers/ata/pata_cs5536.c (revision f42b3800)
1 /*
2  * pata_cs5536.c	- CS5536 PATA for new ATA layer
3  *			  (C) 2007 Martin K. Petersen <mkp@mkp.net>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307	 USA
17  *
18  * Documentation:
19  *	Available from AMD web site.
20  *
21  * The IDE timing registers for the CS5536 live in the Geode Machine
22  * Specific Register file and not PCI config space.  Most BIOSes
23  * virtualize the PCI registers so the chip looks like a standard IDE
24  * controller.	Unfortunately not all implementations get this right.
25  * In particular some have problems with unaligned accesses to the
26  * virtualized PCI registers.  This driver always does full dword
27  * writes to work around the issue.  Also, in case of a bad BIOS this
28  * driver can be loaded with the "msr=1" parameter which forces using
29  * the Machine Specific Registers to configure the device.
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 <linux/libata.h>
39 #include <scsi/scsi_host.h>
40 #include <asm/msr.h>
41 
42 #define DRV_NAME	"pata_cs5536"
43 #define DRV_VERSION	"0.0.7"
44 
45 enum {
46 	CFG			= 0,
47 	DTC			= 1,
48 	CAST			= 2,
49 	ETC			= 3,
50 
51 	MSR_IDE_BASE		= 0x51300000,
52 	MSR_IDE_CFG		= (MSR_IDE_BASE + 0x10),
53 	MSR_IDE_DTC		= (MSR_IDE_BASE + 0x12),
54 	MSR_IDE_CAST		= (MSR_IDE_BASE + 0x13),
55 	MSR_IDE_ETC		= (MSR_IDE_BASE + 0x14),
56 
57 	PCI_IDE_CFG		= 0x40,
58 	PCI_IDE_DTC		= 0x48,
59 	PCI_IDE_CAST		= 0x4c,
60 	PCI_IDE_ETC		= 0x50,
61 
62 	IDE_CFG_CHANEN		= 0x2,
63 	IDE_CFG_CABLE		= 0x10000,
64 
65 	IDE_D0_SHIFT		= 24,
66 	IDE_D1_SHIFT		= 16,
67 	IDE_DRV_MASK		= 0xff,
68 
69 	IDE_CAST_D0_SHIFT	= 6,
70 	IDE_CAST_D1_SHIFT	= 4,
71 	IDE_CAST_DRV_MASK	= 0x3,
72 	IDE_CAST_CMD_MASK	= 0xff,
73 	IDE_CAST_CMD_SHIFT	= 24,
74 
75 	IDE_ETC_NODMA		= 0x03,
76 };
77 
78 static int use_msr;
79 
80 static const u32 msr_reg[4] = {
81 	MSR_IDE_CFG, MSR_IDE_DTC, MSR_IDE_CAST, MSR_IDE_ETC,
82 };
83 
84 static const u8 pci_reg[4] = {
85 	PCI_IDE_CFG, PCI_IDE_DTC, PCI_IDE_CAST, PCI_IDE_ETC,
86 };
87 
88 static inline int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
89 {
90 	if (unlikely(use_msr)) {
91 		u32 dummy;
92 
93 		rdmsr(msr_reg[reg], *val, dummy);
94 		return 0;
95 	}
96 
97 	return pci_read_config_dword(pdev, pci_reg[reg], val);
98 }
99 
100 static inline int cs5536_write(struct pci_dev *pdev, int reg, int val)
101 {
102 	if (unlikely(use_msr)) {
103 		wrmsr(msr_reg[reg], val, 0);
104 		return 0;
105 	}
106 
107 	return pci_write_config_dword(pdev, pci_reg[reg], val);
108 }
109 
110 /**
111  *	cs5536_cable_detect	-	detect cable type
112  *	@ap: Port to detect on
113  *	@deadline: deadline jiffies for the operation
114  *
115  *	Perform cable detection for ATA66 capable cable. Return a libata
116  *	cable type.
117  */
118 
119 static int cs5536_cable_detect(struct ata_port *ap)
120 {
121 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
122 	u32 cfg;
123 
124 	cs5536_read(pdev, CFG, &cfg);
125 
126 	if (cfg & (IDE_CFG_CABLE << ap->port_no))
127 		return ATA_CBL_PATA80;
128 	else
129 		return ATA_CBL_PATA40;
130 }
131 
132 /**
133  *	cs5536_set_piomode		-	PIO setup
134  *	@ap: ATA interface
135  *	@adev: device on the interface
136  */
137 
138 static void cs5536_set_piomode(struct ata_port *ap, struct ata_device *adev)
139 {
140 	static const u8 drv_timings[5] = {
141 		0x98, 0x55, 0x32, 0x21, 0x20,
142 	};
143 
144 	static const u8 addr_timings[5] = {
145 		0x2, 0x1, 0x0, 0x0, 0x0,
146 	};
147 
148 	static const u8 cmd_timings[5] = {
149 		0x99, 0x92, 0x90, 0x22, 0x20,
150 	};
151 
152 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
153 	struct ata_device *pair = ata_dev_pair(adev);
154 	int mode = adev->pio_mode - XFER_PIO_0;
155 	int cmdmode = mode;
156 	int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
157 	int cshift = adev->devno ? IDE_CAST_D1_SHIFT : IDE_CAST_D0_SHIFT;
158 	u32 dtc, cast, etc;
159 
160 	if (pair)
161 		cmdmode = min(mode, pair->pio_mode - XFER_PIO_0);
162 
163 	cs5536_read(pdev, DTC, &dtc);
164 	cs5536_read(pdev, CAST, &cast);
165 	cs5536_read(pdev, ETC, &etc);
166 
167 	dtc &= ~(IDE_DRV_MASK << dshift);
168 	dtc |= drv_timings[mode] << dshift;
169 
170 	cast &= ~(IDE_CAST_DRV_MASK << cshift);
171 	cast |= addr_timings[mode] << cshift;
172 
173 	cast &= ~(IDE_CAST_CMD_MASK << IDE_CAST_CMD_SHIFT);
174 	cast |= cmd_timings[cmdmode] << IDE_CAST_CMD_SHIFT;
175 
176 	etc &= ~(IDE_DRV_MASK << dshift);
177 	etc |= IDE_ETC_NODMA << dshift;
178 
179 	cs5536_write(pdev, DTC, dtc);
180 	cs5536_write(pdev, CAST, cast);
181 	cs5536_write(pdev, ETC, etc);
182 }
183 
184 /**
185  *	cs5536_set_dmamode		-	DMA timing setup
186  *	@ap: ATA interface
187  *	@adev: Device being configured
188  *
189  */
190 
191 static void cs5536_set_dmamode(struct ata_port *ap, struct ata_device *adev)
192 {
193 	static const u8 udma_timings[6] = {
194 		0xc2, 0xc1, 0xc0, 0xc4, 0xc5, 0xc6,
195 	};
196 
197 	static const u8 mwdma_timings[3] = {
198 		0x67, 0x21, 0x20,
199 	};
200 
201 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
202 	u32 dtc, etc;
203 	int mode = adev->dma_mode;
204 	int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
205 
206 	if (mode >= XFER_UDMA_0) {
207 		cs5536_read(pdev, ETC, &etc);
208 
209 		etc &= ~(IDE_DRV_MASK << dshift);
210 		etc |= udma_timings[mode - XFER_UDMA_0] << dshift;
211 
212 		cs5536_write(pdev, ETC, etc);
213 	} else { /* MWDMA */
214 		cs5536_read(pdev, DTC, &dtc);
215 
216 		dtc &= ~(IDE_DRV_MASK << dshift);
217 		dtc |= mwdma_timings[mode - XFER_MW_DMA_0] << dshift;
218 
219 		cs5536_write(pdev, DTC, dtc);
220 	}
221 }
222 
223 static struct scsi_host_template cs5536_sht = {
224 	ATA_BMDMA_SHT(DRV_NAME),
225 };
226 
227 static struct ata_port_operations cs5536_port_ops = {
228 	.inherits		= &ata_bmdma_port_ops,
229 	.cable_detect		= cs5536_cable_detect,
230 	.set_piomode		= cs5536_set_piomode,
231 	.set_dmamode		= cs5536_set_dmamode,
232 };
233 
234 /**
235  *	cs5536_init_one
236  *	@dev: PCI device
237  *	@id: Entry in match table
238  *
239  */
240 
241 static int cs5536_init_one(struct pci_dev *dev, const struct pci_device_id *id)
242 {
243 	static const struct ata_port_info info = {
244 		.flags = ATA_FLAG_SLAVE_POSS,
245 		.pio_mask = 0x1f,
246 		.mwdma_mask = 0x07,
247 		.udma_mask = ATA_UDMA5,
248 		.port_ops = &cs5536_port_ops,
249 	};
250 
251 	const struct ata_port_info *ppi[] = { &info, &ata_dummy_port_info };
252 	u32 cfg;
253 
254 	if (use_msr)
255 		printk(KERN_ERR DRV_NAME ": Using MSR regs instead of PCI\n");
256 
257 	cs5536_read(dev, CFG, &cfg);
258 
259 	if ((cfg & IDE_CFG_CHANEN) == 0) {
260 		printk(KERN_ERR DRV_NAME ": disabled by BIOS\n");
261 		return -ENODEV;
262 	}
263 
264 	return ata_pci_sff_init_one(dev, ppi, &cs5536_sht, NULL);
265 }
266 
267 static const struct pci_device_id cs5536[] = {
268 	{ PCI_VDEVICE(AMD,	PCI_DEVICE_ID_AMD_CS5536_IDE), },
269 	{ },
270 };
271 
272 static struct pci_driver cs5536_pci_driver = {
273 	.name		= DRV_NAME,
274 	.id_table	= cs5536,
275 	.probe		= cs5536_init_one,
276 	.remove		= ata_pci_remove_one,
277 #ifdef CONFIG_PM
278 	.suspend	= ata_pci_device_suspend,
279 	.resume		= ata_pci_device_resume,
280 #endif
281 };
282 
283 static int __init cs5536_init(void)
284 {
285 	return pci_register_driver(&cs5536_pci_driver);
286 }
287 
288 static void __exit cs5536_exit(void)
289 {
290 	pci_unregister_driver(&cs5536_pci_driver);
291 }
292 
293 MODULE_AUTHOR("Martin K. Petersen");
294 MODULE_DESCRIPTION("low-level driver for the CS5536 IDE controller");
295 MODULE_LICENSE("GPL");
296 MODULE_DEVICE_TABLE(pci, cs5536);
297 MODULE_VERSION(DRV_VERSION);
298 module_param_named(msr, use_msr, int, 0644);
299 MODULE_PARM_DESC(msr, "Force using MSR to configure IDE function (Default: 0)");
300 
301 module_init(cs5536_init);
302 module_exit(cs5536_exit);
303