1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * pata_sl82c105.c - SL82C105 PATA for new ATA layer
4 * (C) 2005 Red Hat Inc
5 * (C) 2011 Bartlomiej Zolnierkiewicz
6 *
7 * Based in part on linux/drivers/ide/pci/sl82c105.c
8 * SL82C105/Winbond 553 IDE driver
9 *
10 * and in part on the documentation and errata sheet
11 *
12 *
13 * Note: The controller like many controllers has shared timings for
14 * PIO and DMA. We thus flip to the DMA timings in dma_start and flip back
15 * in the dma_stop function. Thus we actually don't need a set_dmamode
16 * method as the PIO method is always called and will set the right PIO
17 * timing parameters.
18 */
19
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/pci.h>
23 #include <linux/blkdev.h>
24 #include <linux/delay.h>
25 #include <scsi/scsi_host.h>
26 #include <linux/libata.h>
27
28 #define DRV_NAME "pata_sl82c105"
29 #define DRV_VERSION "0.3.3"
30
31 enum {
32 /*
33 * SL82C105 PCI config register 0x40 bits.
34 */
35 CTRL_IDE_IRQB = (1 << 30),
36 CTRL_IDE_IRQA = (1 << 28),
37 CTRL_LEGIRQ = (1 << 11),
38 CTRL_P1F16 = (1 << 5),
39 CTRL_P1EN = (1 << 4),
40 CTRL_P0F16 = (1 << 1),
41 CTRL_P0EN = (1 << 0)
42 };
43
44 /**
45 * sl82c105_pre_reset - probe begin
46 * @link: ATA link
47 * @deadline: deadline jiffies for the operation
48 *
49 * Set up cable type and use generic probe init
50 */
51
sl82c105_pre_reset(struct ata_link * link,unsigned long deadline)52 static int sl82c105_pre_reset(struct ata_link *link, unsigned long deadline)
53 {
54 static const struct pci_bits sl82c105_enable_bits[] = {
55 { 0x40, 1, 0x01, 0x01 },
56 { 0x40, 1, 0x10, 0x10 }
57 };
58 struct ata_port *ap = link->ap;
59 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
60
61 if (ap->port_no && !pci_test_config_bits(pdev, &sl82c105_enable_bits[ap->port_no]))
62 return -ENOENT;
63 return ata_sff_prereset(link, deadline);
64 }
65
66
67 /**
68 * sl82c105_configure_piomode - set chip PIO timing
69 * @ap: ATA interface
70 * @adev: ATA device
71 * @pio: PIO mode
72 *
73 * Called to do the PIO mode setup. Our timing registers are shared
74 * so a configure_dmamode call will undo any work we do here and vice
75 * versa
76 */
77
sl82c105_configure_piomode(struct ata_port * ap,struct ata_device * adev,int pio)78 static void sl82c105_configure_piomode(struct ata_port *ap, struct ata_device *adev, int pio)
79 {
80 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
81 static u16 pio_timing[5] = {
82 0x50D, 0x407, 0x304, 0x242, 0x240
83 };
84 u16 dummy;
85 int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);
86
87 pci_write_config_word(pdev, timing, pio_timing[pio]);
88 /* Can we lose this oddity of the old driver */
89 pci_read_config_word(pdev, timing, &dummy);
90 }
91
92 /**
93 * sl82c105_set_piomode - set initial PIO mode data
94 * @ap: ATA interface
95 * @adev: ATA device
96 *
97 * Called to do the PIO mode setup. Our timing registers are shared
98 * but we want to set the PIO timing by default.
99 */
100
sl82c105_set_piomode(struct ata_port * ap,struct ata_device * adev)101 static void sl82c105_set_piomode(struct ata_port *ap, struct ata_device *adev)
102 {
103 sl82c105_configure_piomode(ap, adev, adev->pio_mode - XFER_PIO_0);
104 }
105
106 /**
107 * sl82c105_configure_dmamode - set DMA mode in chip
108 * @ap: ATA interface
109 * @adev: ATA device
110 *
111 * Load DMA cycle times into the chip ready for a DMA transfer
112 * to occur.
113 */
114
sl82c105_configure_dmamode(struct ata_port * ap,struct ata_device * adev)115 static void sl82c105_configure_dmamode(struct ata_port *ap, struct ata_device *adev)
116 {
117 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
118 static u16 dma_timing[3] = {
119 0x707, 0x201, 0x200
120 };
121 u16 dummy;
122 int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);
123 int dma = adev->dma_mode - XFER_MW_DMA_0;
124
125 pci_write_config_word(pdev, timing, dma_timing[dma]);
126 /* Can we lose this oddity of the old driver */
127 pci_read_config_word(pdev, timing, &dummy);
128 }
129
130 /**
131 * sl82c105_reset_engine - Reset the DMA engine
132 * @ap: ATA interface
133 *
134 * The sl82c105 has some serious problems with the DMA engine
135 * when transfers don't run as expected or ATAPI is used. The
136 * recommended fix is to reset the engine each use using a chip
137 * test register.
138 */
139
sl82c105_reset_engine(struct ata_port * ap)140 static void sl82c105_reset_engine(struct ata_port *ap)
141 {
142 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
143 u16 val;
144
145 pci_read_config_word(pdev, 0x7E, &val);
146 pci_write_config_word(pdev, 0x7E, val | 4);
147 pci_write_config_word(pdev, 0x7E, val & ~4);
148 }
149
150 /**
151 * sl82c105_bmdma_start - DMA engine begin
152 * @qc: ATA command
153 *
154 * Reset the DMA engine each use as recommended by the errata
155 * document.
156 *
157 * FIXME: if we switch clock at BMDMA start/end we might get better
158 * PIO performance on DMA capable devices.
159 */
160
sl82c105_bmdma_start(struct ata_queued_cmd * qc)161 static void sl82c105_bmdma_start(struct ata_queued_cmd *qc)
162 {
163 struct ata_port *ap = qc->ap;
164
165 udelay(100);
166 sl82c105_reset_engine(ap);
167 udelay(100);
168
169 /* Set the clocks for DMA */
170 sl82c105_configure_dmamode(ap, qc->dev);
171 /* Activate DMA */
172 ata_bmdma_start(qc);
173 }
174
175 /**
176 * sl82c105_bmdma_end - DMA engine stop
177 * @qc: ATA command
178 *
179 * Reset the DMA engine each use as recommended by the errata
180 * document.
181 *
182 * This function is also called to turn off DMA when a timeout occurs
183 * during DMA operation. In both cases we need to reset the engine,
184 * so no actual eng_timeout handler is required.
185 *
186 * We assume bmdma_stop is always called if bmdma_start as called. If
187 * not then we may need to wrap qc_issue.
188 */
189
sl82c105_bmdma_stop(struct ata_queued_cmd * qc)190 static void sl82c105_bmdma_stop(struct ata_queued_cmd *qc)
191 {
192 struct ata_port *ap = qc->ap;
193
194 ata_bmdma_stop(qc);
195 sl82c105_reset_engine(ap);
196 udelay(100);
197
198 /* This will redo the initial setup of the DMA device to matching
199 PIO timings */
200 sl82c105_set_piomode(ap, qc->dev);
201 }
202
203 /**
204 * sl82c105_qc_defer - implement serialization
205 * @qc: command
206 *
207 * We must issue one command per host not per channel because
208 * of the reset bug.
209 *
210 * Q: is the scsi host lock sufficient ?
211 */
212
sl82c105_qc_defer(struct ata_queued_cmd * qc)213 static int sl82c105_qc_defer(struct ata_queued_cmd *qc)
214 {
215 struct ata_host *host = qc->ap->host;
216 struct ata_port *alt = host->ports[1 ^ qc->ap->port_no];
217 int rc;
218
219 /* First apply the usual rules */
220 rc = ata_std_qc_defer(qc);
221 if (rc != 0)
222 return rc;
223
224 /* Now apply serialization rules. Only allow a command if the
225 other channel state machine is idle */
226 if (alt && alt->qc_active)
227 return ATA_DEFER_PORT;
228 return 0;
229 }
230
sl82c105_sff_irq_check(struct ata_port * ap)231 static bool sl82c105_sff_irq_check(struct ata_port *ap)
232 {
233 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
234 u32 val, mask = ap->port_no ? CTRL_IDE_IRQB : CTRL_IDE_IRQA;
235
236 pci_read_config_dword(pdev, 0x40, &val);
237
238 return val & mask;
239 }
240
241 static struct scsi_host_template sl82c105_sht = {
242 ATA_BMDMA_SHT(DRV_NAME),
243 };
244
245 static struct ata_port_operations sl82c105_port_ops = {
246 .inherits = &ata_bmdma_port_ops,
247 .qc_defer = sl82c105_qc_defer,
248 .bmdma_start = sl82c105_bmdma_start,
249 .bmdma_stop = sl82c105_bmdma_stop,
250 .cable_detect = ata_cable_40wire,
251 .set_piomode = sl82c105_set_piomode,
252 .prereset = sl82c105_pre_reset,
253 .sff_irq_check = sl82c105_sff_irq_check,
254 };
255
256 /**
257 * sl82c105_bridge_revision - find bridge version
258 * @pdev: PCI device for the ATA function
259 *
260 * Locates the PCI bridge associated with the ATA function and
261 * providing it is a Winbond 553 reports the revision. If it cannot
262 * find a revision or the right device it returns -1
263 */
264
sl82c105_bridge_revision(struct pci_dev * pdev)265 static int sl82c105_bridge_revision(struct pci_dev *pdev)
266 {
267 struct pci_dev *bridge;
268
269 /*
270 * The bridge should be part of the same device, but function 0.
271 */
272 bridge = pci_get_slot(pdev->bus,
273 PCI_DEVFN(PCI_SLOT(pdev->devfn), 0));
274 if (!bridge)
275 return -1;
276
277 /*
278 * Make sure it is a Winbond 553 and is an ISA bridge.
279 */
280 if (bridge->vendor != PCI_VENDOR_ID_WINBOND ||
281 bridge->device != PCI_DEVICE_ID_WINBOND_83C553 ||
282 bridge->class >> 8 != PCI_CLASS_BRIDGE_ISA) {
283 pci_dev_put(bridge);
284 return -1;
285 }
286 /*
287 * We need to find function 0's revision, not function 1
288 */
289 pci_dev_put(bridge);
290 return bridge->revision;
291 }
292
sl82c105_fixup(struct pci_dev * pdev)293 static void sl82c105_fixup(struct pci_dev *pdev)
294 {
295 u32 val;
296
297 pci_read_config_dword(pdev, 0x40, &val);
298 val |= CTRL_P0EN | CTRL_P0F16 | CTRL_P1F16;
299 pci_write_config_dword(pdev, 0x40, val);
300 }
301
sl82c105_init_one(struct pci_dev * dev,const struct pci_device_id * id)302 static int sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id)
303 {
304 static const struct ata_port_info info_dma = {
305 .flags = ATA_FLAG_SLAVE_POSS,
306 .pio_mask = ATA_PIO4,
307 .mwdma_mask = ATA_MWDMA2,
308 .port_ops = &sl82c105_port_ops
309 };
310 static const struct ata_port_info info_early = {
311 .flags = ATA_FLAG_SLAVE_POSS,
312 .pio_mask = ATA_PIO4,
313 .port_ops = &sl82c105_port_ops
314 };
315 /* for now use only the first port */
316 const struct ata_port_info *ppi[] = { &info_early,
317 NULL };
318 int rev;
319 int rc;
320
321 rc = pcim_enable_device(dev);
322 if (rc)
323 return rc;
324
325 rev = sl82c105_bridge_revision(dev);
326
327 if (rev == -1)
328 dev_warn(&dev->dev,
329 "pata_sl82c105: Unable to find bridge, disabling DMA\n");
330 else if (rev <= 5)
331 dev_warn(&dev->dev,
332 "pata_sl82c105: Early bridge revision, no DMA available\n");
333 else
334 ppi[0] = &info_dma;
335
336 sl82c105_fixup(dev);
337
338 return ata_pci_bmdma_init_one(dev, ppi, &sl82c105_sht, NULL, 0);
339 }
340
341 #ifdef CONFIG_PM_SLEEP
sl82c105_reinit_one(struct pci_dev * pdev)342 static int sl82c105_reinit_one(struct pci_dev *pdev)
343 {
344 struct ata_host *host = pci_get_drvdata(pdev);
345 int rc;
346
347 rc = ata_pci_device_do_resume(pdev);
348 if (rc)
349 return rc;
350
351 sl82c105_fixup(pdev);
352
353 ata_host_resume(host);
354 return 0;
355 }
356 #endif
357
358 static const struct pci_device_id sl82c105[] = {
359 { PCI_VDEVICE(WINBOND, PCI_DEVICE_ID_WINBOND_82C105), },
360
361 { },
362 };
363
364 static struct pci_driver sl82c105_pci_driver = {
365 .name = DRV_NAME,
366 .id_table = sl82c105,
367 .probe = sl82c105_init_one,
368 .remove = ata_pci_remove_one,
369 #ifdef CONFIG_PM_SLEEP
370 .suspend = ata_pci_device_suspend,
371 .resume = sl82c105_reinit_one,
372 #endif
373 };
374
375 module_pci_driver(sl82c105_pci_driver);
376
377 MODULE_AUTHOR("Alan Cox");
378 MODULE_DESCRIPTION("low-level driver for Sl82c105");
379 MODULE_LICENSE("GPL");
380 MODULE_DEVICE_TABLE(pci, sl82c105);
381 MODULE_VERSION(DRV_VERSION);
382