1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * pata_cs5536.c - CS5536 PATA for new ATA layer
4 * (C) 2007 Martin K. Petersen <mkp@mkp.net>
5 * (C) 2011 Bartlomiej Zolnierkiewicz
6 *
7 * Documentation:
8 * Available from AMD web site.
9 *
10 * The IDE timing registers for the CS5536 live in the Geode Machine
11 * Specific Register file and not PCI config space. Most BIOSes
12 * virtualize the PCI registers so the chip looks like a standard IDE
13 * controller. Unfortunately not all implementations get this right.
14 * In particular some have problems with unaligned accesses to the
15 * virtualized PCI registers. This driver always does full dword
16 * writes to work around the issue. Also, in case of a bad BIOS this
17 * driver can be loaded with the "msr=1" parameter which forces using
18 * the Machine Specific Registers to configure the device.
19 */
20
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/pci.h>
24 #include <linux/blkdev.h>
25 #include <linux/delay.h>
26 #include <linux/libata.h>
27 #include <scsi/scsi_host.h>
28 #include <linux/dmi.h>
29
30 #ifdef CONFIG_X86_32
31 #include <asm/msr.h>
32 static int use_msr;
33 module_param_named(msr, use_msr, int, 0644);
34 MODULE_PARM_DESC(msr, "Force using MSR to configure IDE function (Default: 0)");
35 #else
36 #undef rdmsr /* avoid accidental MSR usage on, e.g. x86-64 */
37 #undef wrmsr
38 #define rdmsr(x, y, z) do { } while (0)
39 #define wrmsr(x, y, z) do { } while (0)
40 #define use_msr 0
41 #endif
42
43 #define DRV_NAME "pata_cs5536"
44 #define DRV_VERSION "0.0.8"
45
46 enum {
47 MSR_IDE_CFG = 0x51300010,
48 PCI_IDE_CFG = 0x40,
49
50 CFG = 0,
51 DTC = 2,
52 CAST = 3,
53 ETC = 4,
54
55 IDE_CFG_CHANEN = (1 << 1),
56 IDE_CFG_CABLE = (1 << 17) | (1 << 16),
57
58 IDE_D0_SHIFT = 24,
59 IDE_D1_SHIFT = 16,
60 IDE_DRV_MASK = 0xff,
61
62 IDE_CAST_D0_SHIFT = 6,
63 IDE_CAST_D1_SHIFT = 4,
64 IDE_CAST_DRV_MASK = 0x3,
65 IDE_CAST_CMD_MASK = 0xff,
66 IDE_CAST_CMD_SHIFT = 24,
67
68 IDE_ETC_UDMA_MASK = 0xc0,
69 };
70
71 /* Some Bachmann OT200 devices have a non working UDMA support due a
72 * missing resistor.
73 */
74 static const struct dmi_system_id udma_quirk_dmi_table[] = {
75 {
76 .ident = "Bachmann electronic OT200",
77 .matches = {
78 DMI_MATCH(DMI_SYS_VENDOR, "Bachmann electronic"),
79 DMI_MATCH(DMI_PRODUCT_NAME, "OT200"),
80 DMI_MATCH(DMI_PRODUCT_VERSION, "1")
81 },
82 },
83 { }
84 };
85
cs5536_read(struct pci_dev * pdev,int reg,u32 * val)86 static int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
87 {
88 if (unlikely(use_msr)) {
89 u32 dummy __maybe_unused;
90
91 rdmsr(MSR_IDE_CFG + reg, *val, dummy);
92 return 0;
93 }
94
95 return pci_read_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
96 }
97
cs5536_write(struct pci_dev * pdev,int reg,int val)98 static int cs5536_write(struct pci_dev *pdev, int reg, int val)
99 {
100 if (unlikely(use_msr)) {
101 wrmsr(MSR_IDE_CFG + reg, val, 0);
102 return 0;
103 }
104
105 return pci_write_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
106 }
107
cs5536_program_dtc(struct ata_device * adev,u8 tim)108 static void cs5536_program_dtc(struct ata_device *adev, u8 tim)
109 {
110 struct pci_dev *pdev = to_pci_dev(adev->link->ap->host->dev);
111 int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
112 u32 dtc;
113
114 cs5536_read(pdev, DTC, &dtc);
115 dtc &= ~(IDE_DRV_MASK << dshift);
116 dtc |= tim << dshift;
117 cs5536_write(pdev, DTC, dtc);
118 }
119
120 /**
121 * cs5536_cable_detect - detect cable type
122 * @ap: Port to detect on
123 *
124 * Perform cable detection for ATA66 capable cable.
125 *
126 * Returns a cable type.
127 */
128
cs5536_cable_detect(struct ata_port * ap)129 static int cs5536_cable_detect(struct ata_port *ap)
130 {
131 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
132 u32 cfg;
133
134 cs5536_read(pdev, CFG, &cfg);
135
136 if (cfg & IDE_CFG_CABLE)
137 return ATA_CBL_PATA80;
138 else
139 return ATA_CBL_PATA40;
140 }
141
142 /**
143 * cs5536_set_piomode - PIO setup
144 * @ap: ATA interface
145 * @adev: device on the interface
146 */
147
cs5536_set_piomode(struct ata_port * ap,struct ata_device * adev)148 static void cs5536_set_piomode(struct ata_port *ap, struct ata_device *adev)
149 {
150 static const u8 drv_timings[5] = {
151 0x98, 0x55, 0x32, 0x21, 0x20,
152 };
153
154 static const u8 addr_timings[5] = {
155 0x2, 0x1, 0x0, 0x0, 0x0,
156 };
157
158 static const u8 cmd_timings[5] = {
159 0x99, 0x92, 0x90, 0x22, 0x20,
160 };
161
162 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
163 struct ata_device *pair = ata_dev_pair(adev);
164 int mode = adev->pio_mode - XFER_PIO_0;
165 int cmdmode = mode;
166 int cshift = adev->devno ? IDE_CAST_D1_SHIFT : IDE_CAST_D0_SHIFT;
167 u32 cast;
168
169 if (pair)
170 cmdmode = min(mode, pair->pio_mode - XFER_PIO_0);
171
172 cs5536_program_dtc(adev, drv_timings[mode]);
173
174 cs5536_read(pdev, CAST, &cast);
175
176 cast &= ~(IDE_CAST_DRV_MASK << cshift);
177 cast |= addr_timings[mode] << cshift;
178
179 cast &= ~(IDE_CAST_CMD_MASK << IDE_CAST_CMD_SHIFT);
180 cast |= cmd_timings[cmdmode] << IDE_CAST_CMD_SHIFT;
181
182 cs5536_write(pdev, CAST, cast);
183 }
184
185 /**
186 * cs5536_set_dmamode - DMA timing setup
187 * @ap: ATA interface
188 * @adev: Device being configured
189 *
190 */
191
cs5536_set_dmamode(struct ata_port * ap,struct ata_device * adev)192 static void cs5536_set_dmamode(struct ata_port *ap, struct ata_device *adev)
193 {
194 static const u8 udma_timings[6] = {
195 0xc2, 0xc1, 0xc0, 0xc4, 0xc5, 0xc6,
196 };
197
198 static const u8 mwdma_timings[3] = {
199 0x67, 0x21, 0x20,
200 };
201
202 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
203 u32 etc;
204 int mode = adev->dma_mode;
205 int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
206
207 cs5536_read(pdev, ETC, &etc);
208
209 if (mode >= XFER_UDMA_0) {
210 etc &= ~(IDE_DRV_MASK << dshift);
211 etc |= udma_timings[mode - XFER_UDMA_0] << dshift;
212 } else { /* MWDMA */
213 etc &= ~(IDE_ETC_UDMA_MASK << dshift);
214 cs5536_program_dtc(adev, mwdma_timings[mode - XFER_MW_DMA_0]);
215 }
216
217 cs5536_write(pdev, ETC, etc);
218 }
219
220 static struct scsi_host_template cs5536_sht = {
221 ATA_BMDMA_SHT(DRV_NAME),
222 };
223
224 static struct ata_port_operations cs5536_port_ops = {
225 .inherits = &ata_bmdma32_port_ops,
226 .cable_detect = cs5536_cable_detect,
227 .set_piomode = cs5536_set_piomode,
228 .set_dmamode = cs5536_set_dmamode,
229 };
230
231 /**
232 * cs5536_init_one
233 * @dev: PCI device
234 * @id: Entry in match table
235 *
236 */
237
cs5536_init_one(struct pci_dev * dev,const struct pci_device_id * id)238 static int cs5536_init_one(struct pci_dev *dev, const struct pci_device_id *id)
239 {
240 static const struct ata_port_info info = {
241 .flags = ATA_FLAG_SLAVE_POSS,
242 .pio_mask = ATA_PIO4,
243 .mwdma_mask = ATA_MWDMA2,
244 .udma_mask = ATA_UDMA5,
245 .port_ops = &cs5536_port_ops,
246 };
247
248 static const struct ata_port_info no_udma_info = {
249 .flags = ATA_FLAG_SLAVE_POSS,
250 .pio_mask = ATA_PIO4,
251 .port_ops = &cs5536_port_ops,
252 };
253
254
255 const struct ata_port_info *ppi[2];
256 u32 cfg;
257
258 if (dmi_check_system(udma_quirk_dmi_table))
259 ppi[0] = &no_udma_info;
260 else
261 ppi[0] = &info;
262
263 ppi[1] = &ata_dummy_port_info;
264
265 if (use_msr)
266 dev_err(&dev->dev, DRV_NAME ": Using MSR regs instead of PCI\n");
267
268 cs5536_read(dev, CFG, &cfg);
269
270 if ((cfg & IDE_CFG_CHANEN) == 0) {
271 dev_err(&dev->dev, DRV_NAME ": disabled by BIOS\n");
272 return -ENODEV;
273 }
274
275 return ata_pci_bmdma_init_one(dev, ppi, &cs5536_sht, NULL, 0);
276 }
277
278 static const struct pci_device_id cs5536[] = {
279 { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_CS5536_IDE), },
280 { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_CS5536_DEV_IDE), },
281 { },
282 };
283
284 static struct pci_driver cs5536_pci_driver = {
285 .name = DRV_NAME,
286 .id_table = cs5536,
287 .probe = cs5536_init_one,
288 .remove = ata_pci_remove_one,
289 #ifdef CONFIG_PM_SLEEP
290 .suspend = ata_pci_device_suspend,
291 .resume = ata_pci_device_resume,
292 #endif
293 };
294
295 module_pci_driver(cs5536_pci_driver);
296
297 MODULE_AUTHOR("Martin K. Petersen");
298 MODULE_DESCRIPTION("low-level driver for the CS5536 IDE controller");
299 MODULE_LICENSE("GPL");
300 MODULE_DEVICE_TABLE(pci, cs5536);
301 MODULE_VERSION(DRV_VERSION);
302