xref: /openbmc/linux/drivers/ata/pata_cs5536.c (revision d0b73b48)
1 /*
2  * pata_cs5536.c	- CS5536 PATA for new ATA layer
3  *			  (C) 2007 Martin K. Petersen <mkp@mkp.net>
4  *			  (C) 2011 Bartlomiej Zolnierkiewicz
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307	 USA
18  *
19  * Documentation:
20  *	Available from AMD web site.
21  *
22  * The IDE timing registers for the CS5536 live in the Geode Machine
23  * Specific Register file and not PCI config space.  Most BIOSes
24  * virtualize the PCI registers so the chip looks like a standard IDE
25  * controller.	Unfortunately not all implementations get this right.
26  * In particular some have problems with unaligned accesses to the
27  * virtualized PCI registers.  This driver always does full dword
28  * writes to work around the issue.  Also, in case of a bad BIOS this
29  * driver can be loaded with the "msr=1" parameter which forces using
30  * the Machine Specific Registers to configure the device.
31  */
32 
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/pci.h>
36 #include <linux/init.h>
37 #include <linux/blkdev.h>
38 #include <linux/delay.h>
39 #include <linux/libata.h>
40 #include <scsi/scsi_host.h>
41 #include <linux/dmi.h>
42 
43 #ifdef CONFIG_X86_32
44 #include <asm/msr.h>
45 static int use_msr;
46 module_param_named(msr, use_msr, int, 0644);
47 MODULE_PARM_DESC(msr, "Force using MSR to configure IDE function (Default: 0)");
48 #else
49 #undef rdmsr	/* avoid accidental MSR usage on, e.g. x86-64 */
50 #undef wrmsr
51 #define rdmsr(x, y, z) do { } while (0)
52 #define wrmsr(x, y, z) do { } while (0)
53 #define use_msr 0
54 #endif
55 
56 #define DRV_NAME	"pata_cs5536"
57 #define DRV_VERSION	"0.0.8"
58 
59 enum {
60 	MSR_IDE_CFG		= 0x51300010,
61 	PCI_IDE_CFG		= 0x40,
62 
63 	CFG			= 0,
64 	DTC			= 2,
65 	CAST			= 3,
66 	ETC			= 4,
67 
68 	IDE_CFG_CHANEN		= (1 << 1),
69 	IDE_CFG_CABLE		= (1 << 17) | (1 << 16),
70 
71 	IDE_D0_SHIFT		= 24,
72 	IDE_D1_SHIFT		= 16,
73 	IDE_DRV_MASK		= 0xff,
74 
75 	IDE_CAST_D0_SHIFT	= 6,
76 	IDE_CAST_D1_SHIFT	= 4,
77 	IDE_CAST_DRV_MASK	= 0x3,
78 	IDE_CAST_CMD_MASK	= 0xff,
79 	IDE_CAST_CMD_SHIFT	= 24,
80 
81 	IDE_ETC_UDMA_MASK	= 0xc0,
82 };
83 
84 /* Some Bachmann OT200 devices have a non working UDMA support due a
85  * missing resistor.
86  */
87 static const struct dmi_system_id udma_quirk_dmi_table[] = {
88 	{
89 		.ident = "Bachmann electronic OT200",
90 		.matches = {
91 			DMI_MATCH(DMI_SYS_VENDOR, "Bachmann electronic"),
92 			DMI_MATCH(DMI_PRODUCT_NAME, "OT200"),
93 			DMI_MATCH(DMI_PRODUCT_VERSION, "1")
94 		},
95 	},
96 	{ }
97 };
98 
99 static int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
100 {
101 	if (unlikely(use_msr)) {
102 		u32 dummy __maybe_unused;
103 
104 		rdmsr(MSR_IDE_CFG + reg, *val, dummy);
105 		return 0;
106 	}
107 
108 	return pci_read_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
109 }
110 
111 static int cs5536_write(struct pci_dev *pdev, int reg, int val)
112 {
113 	if (unlikely(use_msr)) {
114 		wrmsr(MSR_IDE_CFG + reg, val, 0);
115 		return 0;
116 	}
117 
118 	return pci_write_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
119 }
120 
121 static void cs5536_program_dtc(struct ata_device *adev, u8 tim)
122 {
123 	struct pci_dev *pdev = to_pci_dev(adev->link->ap->host->dev);
124 	int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
125 	u32 dtc;
126 
127 	cs5536_read(pdev, DTC, &dtc);
128 	dtc &= ~(IDE_DRV_MASK << dshift);
129 	dtc |= tim << dshift;
130 	cs5536_write(pdev, DTC, dtc);
131 }
132 
133 /**
134  *	cs5536_cable_detect	-	detect cable type
135  *	@ap: Port to detect on
136  *
137  *	Perform cable detection for ATA66 capable cable.
138  *
139  *	Returns a cable type.
140  */
141 
142 static int cs5536_cable_detect(struct ata_port *ap)
143 {
144 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
145 	u32 cfg;
146 
147 	cs5536_read(pdev, CFG, &cfg);
148 
149 	if (cfg & IDE_CFG_CABLE)
150 		return ATA_CBL_PATA80;
151 	else
152 		return ATA_CBL_PATA40;
153 }
154 
155 /**
156  *	cs5536_set_piomode		-	PIO setup
157  *	@ap: ATA interface
158  *	@adev: device on the interface
159  */
160 
161 static void cs5536_set_piomode(struct ata_port *ap, struct ata_device *adev)
162 {
163 	static const u8 drv_timings[5] = {
164 		0x98, 0x55, 0x32, 0x21, 0x20,
165 	};
166 
167 	static const u8 addr_timings[5] = {
168 		0x2, 0x1, 0x0, 0x0, 0x0,
169 	};
170 
171 	static const u8 cmd_timings[5] = {
172 		0x99, 0x92, 0x90, 0x22, 0x20,
173 	};
174 
175 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
176 	struct ata_device *pair = ata_dev_pair(adev);
177 	int mode = adev->pio_mode - XFER_PIO_0;
178 	int cmdmode = mode;
179 	int cshift = adev->devno ? IDE_CAST_D1_SHIFT : IDE_CAST_D0_SHIFT;
180 	u32 cast;
181 
182 	if (pair)
183 		cmdmode = min(mode, pair->pio_mode - XFER_PIO_0);
184 
185 	cs5536_program_dtc(adev, drv_timings[mode]);
186 
187 	cs5536_read(pdev, CAST, &cast);
188 
189 	cast &= ~(IDE_CAST_DRV_MASK << cshift);
190 	cast |= addr_timings[mode] << cshift;
191 
192 	cast &= ~(IDE_CAST_CMD_MASK << IDE_CAST_CMD_SHIFT);
193 	cast |= cmd_timings[cmdmode] << IDE_CAST_CMD_SHIFT;
194 
195 	cs5536_write(pdev, CAST, cast);
196 }
197 
198 /**
199  *	cs5536_set_dmamode		-	DMA timing setup
200  *	@ap: ATA interface
201  *	@adev: Device being configured
202  *
203  */
204 
205 static void cs5536_set_dmamode(struct ata_port *ap, struct ata_device *adev)
206 {
207 	static const u8 udma_timings[6] = {
208 		0xc2, 0xc1, 0xc0, 0xc4, 0xc5, 0xc6,
209 	};
210 
211 	static const u8 mwdma_timings[3] = {
212 		0x67, 0x21, 0x20,
213 	};
214 
215 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
216 	u32 etc;
217 	int mode = adev->dma_mode;
218 	int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
219 
220 	cs5536_read(pdev, ETC, &etc);
221 
222 	if (mode >= XFER_UDMA_0) {
223 		etc &= ~(IDE_DRV_MASK << dshift);
224 		etc |= udma_timings[mode - XFER_UDMA_0] << dshift;
225 	} else { /* MWDMA */
226 		etc &= ~(IDE_ETC_UDMA_MASK << dshift);
227 		cs5536_program_dtc(adev, mwdma_timings[mode - XFER_MW_DMA_0]);
228 	}
229 
230 	cs5536_write(pdev, ETC, etc);
231 }
232 
233 static struct scsi_host_template cs5536_sht = {
234 	ATA_BMDMA_SHT(DRV_NAME),
235 };
236 
237 static struct ata_port_operations cs5536_port_ops = {
238 	.inherits		= &ata_bmdma32_port_ops,
239 	.cable_detect		= cs5536_cable_detect,
240 	.set_piomode		= cs5536_set_piomode,
241 	.set_dmamode		= cs5536_set_dmamode,
242 };
243 
244 /**
245  *	cs5536_init_one
246  *	@dev: PCI device
247  *	@id: Entry in match table
248  *
249  */
250 
251 static int cs5536_init_one(struct pci_dev *dev, const struct pci_device_id *id)
252 {
253 	static const struct ata_port_info info = {
254 		.flags = ATA_FLAG_SLAVE_POSS,
255 		.pio_mask = ATA_PIO4,
256 		.mwdma_mask = ATA_MWDMA2,
257 		.udma_mask = ATA_UDMA5,
258 		.port_ops = &cs5536_port_ops,
259 	};
260 
261 	static const struct ata_port_info no_udma_info = {
262 		.flags = ATA_FLAG_SLAVE_POSS,
263 		.pio_mask = ATA_PIO4,
264 		.port_ops = &cs5536_port_ops,
265 	};
266 
267 
268 	const struct ata_port_info *ppi[2];
269 	u32 cfg;
270 
271 	if (dmi_check_system(udma_quirk_dmi_table))
272 		ppi[0] = &no_udma_info;
273 	else
274 		ppi[0] = &info;
275 
276 	ppi[1] = &ata_dummy_port_info;
277 
278 	if (use_msr)
279 		printk(KERN_ERR DRV_NAME ": Using MSR regs instead of PCI\n");
280 
281 	cs5536_read(dev, CFG, &cfg);
282 
283 	if ((cfg & IDE_CFG_CHANEN) == 0) {
284 		printk(KERN_ERR DRV_NAME ": disabled by BIOS\n");
285 		return -ENODEV;
286 	}
287 
288 	return ata_pci_bmdma_init_one(dev, ppi, &cs5536_sht, NULL, 0);
289 }
290 
291 static const struct pci_device_id cs5536[] = {
292 	{ PCI_VDEVICE(AMD,	PCI_DEVICE_ID_AMD_CS5536_IDE), },
293 	{ },
294 };
295 
296 static struct pci_driver cs5536_pci_driver = {
297 	.name		= DRV_NAME,
298 	.id_table	= cs5536,
299 	.probe		= cs5536_init_one,
300 	.remove		= ata_pci_remove_one,
301 #ifdef CONFIG_PM
302 	.suspend	= ata_pci_device_suspend,
303 	.resume		= ata_pci_device_resume,
304 #endif
305 };
306 
307 module_pci_driver(cs5536_pci_driver);
308 
309 MODULE_AUTHOR("Martin K. Petersen");
310 MODULE_DESCRIPTION("low-level driver for the CS5536 IDE controller");
311 MODULE_LICENSE("GPL");
312 MODULE_DEVICE_TABLE(pci, cs5536);
313 MODULE_VERSION(DRV_VERSION);
314