xref: /openbmc/linux/drivers/ata/pata_efar.c (revision dea54fba)
1 /*
2  *    pata_efar.c - EFAR PIIX clone controller driver
3  *
4  *	(C) 2005 Red Hat
5  *	(C) 2009-2010 Bartlomiej Zolnierkiewicz
6  *
7  *    Some parts based on ata_piix.c by Jeff Garzik and others.
8  *
9  *    The EFAR is a PIIX4 clone with UDMA66 support. Unlike the later
10  *    Intel ICH controllers the EFAR widened the UDMA mode register bits
11  *    and doesn't require the funky clock selection.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/pci.h>
17 #include <linux/blkdev.h>
18 #include <linux/delay.h>
19 #include <linux/device.h>
20 #include <scsi/scsi_host.h>
21 #include <linux/libata.h>
22 #include <linux/ata.h>
23 
24 #define DRV_NAME	"pata_efar"
25 #define DRV_VERSION	"0.4.5"
26 
27 /**
28  *	efar_pre_reset	-	Enable bits
29  *	@link: ATA link
30  *	@deadline: deadline jiffies for the operation
31  *
32  *	Perform cable detection for the EFAR ATA interface. This is
33  *	different to the PIIX arrangement
34  */
35 
36 static int efar_pre_reset(struct ata_link *link, unsigned long deadline)
37 {
38 	static const struct pci_bits efar_enable_bits[] = {
39 		{ 0x41U, 1U, 0x80UL, 0x80UL },	/* port 0 */
40 		{ 0x43U, 1U, 0x80UL, 0x80UL },	/* port 1 */
41 	};
42 	struct ata_port *ap = link->ap;
43 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
44 
45 	if (!pci_test_config_bits(pdev, &efar_enable_bits[ap->port_no]))
46 		return -ENOENT;
47 
48 	return ata_sff_prereset(link, deadline);
49 }
50 
51 /**
52  *	efar_cable_detect	-	check for 40/80 pin
53  *	@ap: Port
54  *
55  *	Perform cable detection for the EFAR ATA interface. This is
56  *	different to the PIIX arrangement
57  */
58 
59 static int efar_cable_detect(struct ata_port *ap)
60 {
61 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
62 	u8 tmp;
63 
64 	pci_read_config_byte(pdev, 0x47, &tmp);
65 	if (tmp & (2 >> ap->port_no))
66 		return ATA_CBL_PATA40;
67 	return ATA_CBL_PATA80;
68 }
69 
70 static DEFINE_SPINLOCK(efar_lock);
71 
72 /**
73  *	efar_set_piomode - Initialize host controller PATA PIO timings
74  *	@ap: Port whose timings we are configuring
75  *	@adev: Device to program
76  *
77  *	Set PIO mode for device, in host controller PCI config space.
78  *
79  *	LOCKING:
80  *	None (inherited from caller).
81  */
82 
83 static void efar_set_piomode (struct ata_port *ap, struct ata_device *adev)
84 {
85 	unsigned int pio	= adev->pio_mode - XFER_PIO_0;
86 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
87 	unsigned int master_port = ap->port_no ? 0x42 : 0x40;
88 	unsigned long flags;
89 	u16 master_data;
90 	u8 udma_enable;
91 	int control = 0;
92 
93 	/*
94 	 *	See Intel Document 298600-004 for the timing programing rules
95 	 *	for PIIX/ICH. The EFAR is a clone so very similar
96 	 */
97 
98 	static const	 /* ISP  RTC */
99 	u8 timings[][2]	= { { 0, 0 },
100 			    { 0, 0 },
101 			    { 1, 0 },
102 			    { 2, 1 },
103 			    { 2, 3 }, };
104 
105 	if (pio > 1)
106 		control |= 1;	/* TIME */
107 	if (ata_pio_need_iordy(adev))	/* PIO 3/4 require IORDY */
108 		control |= 2;	/* IE */
109 	/* Intel specifies that the prefetch/posting is for disk only */
110 	if (adev->class == ATA_DEV_ATA)
111 		control |= 4;	/* PPE */
112 
113 	spin_lock_irqsave(&efar_lock, flags);
114 
115 	pci_read_config_word(dev, master_port, &master_data);
116 
117 	/* Set PPE, IE, and TIME as appropriate */
118 	if (adev->devno == 0) {
119 		master_data &= 0xCCF0;
120 		master_data |= control;
121 		master_data |= (timings[pio][0] << 12) |
122 			(timings[pio][1] << 8);
123 	} else {
124 		int shift = 4 * ap->port_no;
125 		u8 slave_data;
126 
127 		master_data &= 0xFF0F;
128 		master_data |= (control << 4);
129 
130 		/* Slave timing in separate register */
131 		pci_read_config_byte(dev, 0x44, &slave_data);
132 		slave_data &= ap->port_no ? 0x0F : 0xF0;
133 		slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << shift;
134 		pci_write_config_byte(dev, 0x44, slave_data);
135 	}
136 
137 	master_data |= 0x4000;	/* Ensure SITRE is set */
138 	pci_write_config_word(dev, master_port, master_data);
139 
140 	pci_read_config_byte(dev, 0x48, &udma_enable);
141 	udma_enable &= ~(1 << (2 * ap->port_no + adev->devno));
142 	pci_write_config_byte(dev, 0x48, udma_enable);
143 	spin_unlock_irqrestore(&efar_lock, flags);
144 }
145 
146 /**
147  *	efar_set_dmamode - Initialize host controller PATA DMA timings
148  *	@ap: Port whose timings we are configuring
149  *	@adev: Device to program
150  *
151  *	Set UDMA/MWDMA mode for device, in host controller PCI config space.
152  *
153  *	LOCKING:
154  *	None (inherited from caller).
155  */
156 
157 static void efar_set_dmamode (struct ata_port *ap, struct ata_device *adev)
158 {
159 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
160 	u8 master_port		= ap->port_no ? 0x42 : 0x40;
161 	u16 master_data;
162 	u8 speed		= adev->dma_mode;
163 	int devid		= adev->devno + 2 * ap->port_no;
164 	unsigned long flags;
165 	u8 udma_enable;
166 
167 	static const	 /* ISP  RTC */
168 	u8 timings[][2]	= { { 0, 0 },
169 			    { 0, 0 },
170 			    { 1, 0 },
171 			    { 2, 1 },
172 			    { 2, 3 }, };
173 
174 	spin_lock_irqsave(&efar_lock, flags);
175 
176 	pci_read_config_word(dev, master_port, &master_data);
177 	pci_read_config_byte(dev, 0x48, &udma_enable);
178 
179 	if (speed >= XFER_UDMA_0) {
180 		unsigned int udma	= adev->dma_mode - XFER_UDMA_0;
181 		u16 udma_timing;
182 
183 		udma_enable |= (1 << devid);
184 
185 		/* Load the UDMA mode number */
186 		pci_read_config_word(dev, 0x4A, &udma_timing);
187 		udma_timing &= ~(7 << (4 * devid));
188 		udma_timing |= udma << (4 * devid);
189 		pci_write_config_word(dev, 0x4A, udma_timing);
190 	} else {
191 		/*
192 		 * MWDMA is driven by the PIO timings. We must also enable
193 		 * IORDY unconditionally along with TIME1. PPE has already
194 		 * been set when the PIO timing was set.
195 		 */
196 		unsigned int mwdma	= adev->dma_mode - XFER_MW_DMA_0;
197 		unsigned int control;
198 		u8 slave_data;
199 		const unsigned int needed_pio[3] = {
200 			XFER_PIO_0, XFER_PIO_3, XFER_PIO_4
201 		};
202 		int pio = needed_pio[mwdma] - XFER_PIO_0;
203 
204 		control = 3;	/* IORDY|TIME1 */
205 
206 		/* If the drive MWDMA is faster than it can do PIO then
207 		   we must force PIO into PIO0 */
208 
209 		if (adev->pio_mode < needed_pio[mwdma])
210 			/* Enable DMA timing only */
211 			control |= 8;	/* PIO cycles in PIO0 */
212 
213 		if (adev->devno) {	/* Slave */
214 			master_data &= 0xFF4F;  /* Mask out IORDY|TIME1|DMAONLY */
215 			master_data |= control << 4;
216 			pci_read_config_byte(dev, 0x44, &slave_data);
217 			slave_data &= ap->port_no ? 0x0F : 0xF0;
218 			/* Load the matching timing */
219 			slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << (ap->port_no ? 4 : 0);
220 			pci_write_config_byte(dev, 0x44, slave_data);
221 		} else { 	/* Master */
222 			master_data &= 0xCCF4;	/* Mask out IORDY|TIME1|DMAONLY
223 						   and master timing bits */
224 			master_data |= control;
225 			master_data |=
226 				(timings[pio][0] << 12) |
227 				(timings[pio][1] << 8);
228 		}
229 		udma_enable &= ~(1 << devid);
230 		pci_write_config_word(dev, master_port, master_data);
231 	}
232 	pci_write_config_byte(dev, 0x48, udma_enable);
233 	spin_unlock_irqrestore(&efar_lock, flags);
234 }
235 
236 static struct scsi_host_template efar_sht = {
237 	ATA_BMDMA_SHT(DRV_NAME),
238 };
239 
240 static struct ata_port_operations efar_ops = {
241 	.inherits		= &ata_bmdma_port_ops,
242 	.cable_detect		= efar_cable_detect,
243 	.set_piomode		= efar_set_piomode,
244 	.set_dmamode		= efar_set_dmamode,
245 	.prereset		= efar_pre_reset,
246 };
247 
248 
249 /**
250  *	efar_init_one - Register EFAR ATA PCI device with kernel services
251  *	@pdev: PCI device to register
252  *	@ent: Entry in efar_pci_tbl matching with @pdev
253  *
254  *	Called from kernel PCI layer.
255  *
256  *	LOCKING:
257  *	Inherited from PCI layer (may sleep).
258  *
259  *	RETURNS:
260  *	Zero on success, or -ERRNO value.
261  */
262 
263 static int efar_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
264 {
265 	static const struct ata_port_info info = {
266 		.flags		= ATA_FLAG_SLAVE_POSS,
267 		.pio_mask	= ATA_PIO4,
268 		.mwdma_mask	= ATA_MWDMA12_ONLY,
269 		.udma_mask 	= ATA_UDMA4,
270 		.port_ops	= &efar_ops,
271 	};
272 	const struct ata_port_info *ppi[] = { &info, &info };
273 
274 	ata_print_version_once(&pdev->dev, DRV_VERSION);
275 
276 	return ata_pci_bmdma_init_one(pdev, ppi, &efar_sht, NULL,
277 				      ATA_HOST_PARALLEL_SCAN);
278 }
279 
280 static const struct pci_device_id efar_pci_tbl[] = {
281 	{ PCI_VDEVICE(EFAR, 0x9130), },
282 
283 	{ }	/* terminate list */
284 };
285 
286 static struct pci_driver efar_pci_driver = {
287 	.name			= DRV_NAME,
288 	.id_table		= efar_pci_tbl,
289 	.probe			= efar_init_one,
290 	.remove			= ata_pci_remove_one,
291 #ifdef CONFIG_PM_SLEEP
292 	.suspend		= ata_pci_device_suspend,
293 	.resume			= ata_pci_device_resume,
294 #endif
295 };
296 
297 module_pci_driver(efar_pci_driver);
298 
299 MODULE_AUTHOR("Alan Cox");
300 MODULE_DESCRIPTION("SCSI low-level driver for EFAR PIIX clones");
301 MODULE_LICENSE("GPL");
302 MODULE_DEVICE_TABLE(pci, efar_pci_tbl);
303 MODULE_VERSION(DRV_VERSION);
304