xref: /openbmc/linux/drivers/ata/pata_sl82c105.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 /*
2  * pata_sl82c105.c 	- SL82C105 PATA for new ATA layer
3  *			  (C) 2005 Red Hat Inc
4  *			  Alan Cox <alan@redhat.com>
5  *
6  * Based in part on linux/drivers/ide/pci/sl82c105.c
7  * 		SL82C105/Winbond 553 IDE driver
8  *
9  * and in part on the documentation and errata sheet
10  *
11  *
12  * Note: The controller like many controllers has shared timings for
13  * PIO and DMA. We thus flip to the DMA timings in dma_start and flip back
14  * in the dma_stop function. Thus we actually don't need a set_dmamode
15  * method as the PIO method is always called and will set the right PIO
16  * timing parameters.
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/pci.h>
22 #include <linux/init.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 "0.3.2"
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 
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_std_prereset(link, deadline);
64 }
65 
66 
67 static void sl82c105_error_handler(struct ata_port *ap)
68 {
69 	ata_bmdma_drive_eh(ap, sl82c105_pre_reset, ata_std_softreset, NULL, ata_std_postreset);
70 }
71 
72 
73 /**
74  *	sl82c105_configure_piomode	-	set chip PIO timing
75  *	@ap: ATA interface
76  *	@adev: ATA device
77  *	@pio: PIO mode
78  *
79  *	Called to do the PIO mode setup. Our timing registers are shared
80  *	so a configure_dmamode call will undo any work we do here and vice
81  *	versa
82  */
83 
84 static void sl82c105_configure_piomode(struct ata_port *ap, struct ata_device *adev, int pio)
85 {
86 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
87 	static u16 pio_timing[5] = {
88 		0x50D, 0x407, 0x304, 0x242, 0x240
89 	};
90 	u16 dummy;
91 	int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);
92 
93 	pci_write_config_word(pdev, timing, pio_timing[pio]);
94 	/* Can we lose this oddity of the old driver */
95 	pci_read_config_word(pdev, timing, &dummy);
96 }
97 
98 /**
99  *	sl82c105_set_piomode	-	set initial PIO mode data
100  *	@ap: ATA interface
101  *	@adev: ATA device
102  *
103  *	Called to do the PIO mode setup. Our timing registers are shared
104  *	but we want to set the PIO timing by default.
105  */
106 
107 static void sl82c105_set_piomode(struct ata_port *ap, struct ata_device *adev)
108 {
109 	sl82c105_configure_piomode(ap, adev, adev->pio_mode - XFER_PIO_0);
110 }
111 
112 /**
113  *	sl82c105_configure_dmamode	-	set DMA mode in chip
114  *	@ap: ATA interface
115  *	@adev: ATA device
116  *
117  *	Load DMA cycle times into the chip ready for a DMA transfer
118  *	to occur.
119  */
120 
121 static void sl82c105_configure_dmamode(struct ata_port *ap, struct ata_device *adev)
122 {
123 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
124 	static u16 dma_timing[3] = {
125 		0x707, 0x201, 0x200
126 	};
127 	u16 dummy;
128 	int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);
129 	int dma = adev->dma_mode - XFER_MW_DMA_0;
130 
131 	pci_write_config_word(pdev, timing, dma_timing[dma]);
132 	/* Can we lose this oddity of the old driver */
133 	pci_read_config_word(pdev, timing, &dummy);
134 }
135 
136 /**
137  *	sl82c105_reset_engine	-	Reset the DMA engine
138  *	@ap: ATA interface
139  *
140  *	The sl82c105 has some serious problems with the DMA engine
141  *	when transfers don't run as expected or ATAPI is used. The
142  *	recommended fix is to reset the engine each use using a chip
143  *	test register.
144  */
145 
146 static void sl82c105_reset_engine(struct ata_port *ap)
147 {
148 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
149 	u16 val;
150 
151 	pci_read_config_word(pdev, 0x7E, &val);
152 	pci_write_config_word(pdev, 0x7E, val | 4);
153 	pci_write_config_word(pdev, 0x7E, val & ~4);
154 }
155 
156 /**
157  *	sl82c105_bmdma_start		-	DMA engine begin
158  *	@qc: ATA command
159  *
160  *	Reset the DMA engine each use as recommended by the errata
161  *	document.
162  *
163  *	FIXME: if we switch clock at BMDMA start/end we might get better
164  *	PIO performance on DMA capable devices.
165  */
166 
167 static void sl82c105_bmdma_start(struct ata_queued_cmd *qc)
168 {
169 	struct ata_port *ap = qc->ap;
170 
171 	udelay(100);
172 	sl82c105_reset_engine(ap);
173 	udelay(100);
174 
175 	/* Set the clocks for DMA */
176 	sl82c105_configure_dmamode(ap, qc->dev);
177 	/* Activate DMA */
178 	ata_bmdma_start(qc);
179 }
180 
181 /**
182  *	sl82c105_bmdma_end		-	DMA engine stop
183  *	@qc: ATA command
184  *
185  *	Reset the DMA engine each use as recommended by the errata
186  *	document.
187  *
188  *	This function is also called to turn off DMA when a timeout occurs
189  *	during DMA operation. In both cases we need to reset the engine,
190  *	so no actual eng_timeout handler is required.
191  *
192  *	We assume bmdma_stop is always called if bmdma_start as called. If
193  *	not then we may need to wrap qc_issue.
194  */
195 
196 static void sl82c105_bmdma_stop(struct ata_queued_cmd *qc)
197 {
198 	struct ata_port *ap = qc->ap;
199 
200 	ata_bmdma_stop(qc);
201 	sl82c105_reset_engine(ap);
202 	udelay(100);
203 
204 	/* This will redo the initial setup of the DMA device to matching
205 	   PIO timings */
206 	sl82c105_set_piomode(ap, qc->dev);
207 }
208 
209 static struct scsi_host_template sl82c105_sht = {
210 	.module			= THIS_MODULE,
211 	.name			= DRV_NAME,
212 	.ioctl			= ata_scsi_ioctl,
213 	.queuecommand		= ata_scsi_queuecmd,
214 	.can_queue		= ATA_DEF_QUEUE,
215 	.this_id		= ATA_SHT_THIS_ID,
216 	.sg_tablesize		= LIBATA_MAX_PRD,
217 	.cmd_per_lun		= ATA_SHT_CMD_PER_LUN,
218 	.emulated		= ATA_SHT_EMULATED,
219 	.use_clustering		= ATA_SHT_USE_CLUSTERING,
220 	.proc_name		= DRV_NAME,
221 	.dma_boundary		= ATA_DMA_BOUNDARY,
222 	.slave_configure	= ata_scsi_slave_config,
223 	.slave_destroy		= ata_scsi_slave_destroy,
224 	.bios_param		= ata_std_bios_param,
225 };
226 
227 static struct ata_port_operations sl82c105_port_ops = {
228 	.set_piomode	= sl82c105_set_piomode,
229 	.mode_filter	= ata_pci_default_filter,
230 
231 	.tf_load	= ata_tf_load,
232 	.tf_read	= ata_tf_read,
233 	.check_status 	= ata_check_status,
234 	.exec_command	= ata_exec_command,
235 	.dev_select 	= ata_std_dev_select,
236 
237 	.freeze		= ata_bmdma_freeze,
238 	.thaw		= ata_bmdma_thaw,
239 	.error_handler	= sl82c105_error_handler,
240 	.post_internal_cmd = ata_bmdma_post_internal_cmd,
241 	.cable_detect	= ata_cable_40wire,
242 
243 	.bmdma_setup 	= ata_bmdma_setup,
244 	.bmdma_start 	= sl82c105_bmdma_start,
245 	.bmdma_stop	= sl82c105_bmdma_stop,
246 	.bmdma_status 	= ata_bmdma_status,
247 
248 	.qc_prep 	= ata_qc_prep,
249 	.qc_issue	= ata_qc_issue_prot,
250 
251 	.data_xfer	= ata_data_xfer,
252 
253 	.irq_handler	= ata_interrupt,
254 	.irq_clear	= ata_bmdma_irq_clear,
255 	.irq_on		= ata_irq_on,
256 
257 	.port_start	= ata_sff_port_start,
258 };
259 
260 /**
261  *	sl82c105_bridge_revision	-	find bridge version
262  *	@pdev: PCI device for the ATA function
263  *
264  *	Locates the PCI bridge associated with the ATA function and
265  *	providing it is a Winbond 553 reports the revision. If it cannot
266  *	find a revision or the right device it returns -1
267  */
268 
269 static int sl82c105_bridge_revision(struct pci_dev *pdev)
270 {
271 	struct pci_dev *bridge;
272 
273 	/*
274 	 * The bridge should be part of the same device, but function 0.
275 	 */
276 	bridge = pci_get_slot(pdev->bus,
277 			       PCI_DEVFN(PCI_SLOT(pdev->devfn), 0));
278 	if (!bridge)
279 		return -1;
280 
281 	/*
282 	 * Make sure it is a Winbond 553 and is an ISA bridge.
283 	 */
284 	if (bridge->vendor != PCI_VENDOR_ID_WINBOND ||
285 	    bridge->device != PCI_DEVICE_ID_WINBOND_83C553 ||
286 	    bridge->class >> 8 != PCI_CLASS_BRIDGE_ISA) {
287 	    	pci_dev_put(bridge);
288 		return -1;
289 	}
290 	/*
291 	 * We need to find function 0's revision, not function 1
292 	 */
293 	pci_dev_put(bridge);
294 	return bridge->revision;
295 }
296 
297 
298 static int sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id)
299 {
300 	static const struct ata_port_info info_dma = {
301 		.sht = &sl82c105_sht,
302 		.flags = ATA_FLAG_SLAVE_POSS,
303 		.pio_mask = 0x1f,
304 		.mwdma_mask = 0x07,
305 		.port_ops = &sl82c105_port_ops
306 	};
307 	static const struct ata_port_info info_early = {
308 		.sht = &sl82c105_sht,
309 		.flags = ATA_FLAG_SLAVE_POSS,
310 		.pio_mask = 0x1f,
311 		.port_ops = &sl82c105_port_ops
312 	};
313 	/* for now use only the first port */
314 	const struct ata_port_info *ppi[] = { &info_early,
315 					       &ata_dummy_port_info };
316 	u32 val;
317 	int rev;
318 
319 	rev = sl82c105_bridge_revision(dev);
320 
321 	if (rev == -1)
322 		dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Unable to find bridge, disabling DMA.\n");
323 	else if (rev <= 5)
324 		dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Early bridge revision, no DMA available.\n");
325 	else
326 		ppi[0] = &info_dma;
327 
328 	pci_read_config_dword(dev, 0x40, &val);
329 	val |= CTRL_P0EN | CTRL_P0F16 | CTRL_P1F16;
330 	pci_write_config_dword(dev, 0x40, val);
331 
332 	return ata_pci_init_one(dev, ppi);
333 }
334 
335 static const struct pci_device_id sl82c105[] = {
336 	{ PCI_VDEVICE(WINBOND, PCI_DEVICE_ID_WINBOND_82C105), },
337 
338 	{ },
339 };
340 
341 static struct pci_driver sl82c105_pci_driver = {
342 	.name 		= DRV_NAME,
343 	.id_table	= sl82c105,
344 	.probe 		= sl82c105_init_one,
345 	.remove		= ata_pci_remove_one
346 };
347 
348 static int __init sl82c105_init(void)
349 {
350 	return pci_register_driver(&sl82c105_pci_driver);
351 }
352 
353 static void __exit sl82c105_exit(void)
354 {
355 	pci_unregister_driver(&sl82c105_pci_driver);
356 }
357 
358 MODULE_AUTHOR("Alan Cox");
359 MODULE_DESCRIPTION("low-level driver for Sl82c105");
360 MODULE_LICENSE("GPL");
361 MODULE_DEVICE_TABLE(pci, sl82c105);
362 MODULE_VERSION(DRV_VERSION);
363 
364 module_init(sl82c105_init);
365 module_exit(sl82c105_exit);
366