xref: /openbmc/linux/drivers/ata/pata_efar.c (revision 9aa2cba7)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *    pata_efar.c - EFAR PIIX clone controller driver
4  *
5  *	(C) 2005 Red Hat
6  *	(C) 2009-2010 Bartlomiej Zolnierkiewicz
7  *
8  *    Some parts based on ata_piix.c by Jeff Garzik and others.
9  *
10  *    The EFAR is a PIIX4 clone with UDMA66 support. Unlike the later
11  *    Intel ICH controllers the EFAR widened the UDMA mode register bits
12  *    and doesn't require the funky clock selection.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/pci.h>
18 #include <linux/blkdev.h>
19 #include <linux/delay.h>
20 #include <linux/device.h>
21 #include <scsi/scsi_host.h>
22 #include <linux/libata.h>
23 #include <linux/ata.h>
24 
25 #define DRV_NAME	"pata_efar"
26 #define DRV_VERSION	"0.4.5"
27 
28 /**
29  *	efar_pre_reset	-	Enable bits
30  *	@link: ATA link
31  *	@deadline: deadline jiffies for the operation
32  *
33  *	Perform cable detection for the EFAR ATA interface. This is
34  *	different to the PIIX arrangement
35  */
36 
37 static int efar_pre_reset(struct ata_link *link, unsigned long deadline)
38 {
39 	static const struct pci_bits efar_enable_bits[] = {
40 		{ 0x41U, 1U, 0x80UL, 0x80UL },	/* port 0 */
41 		{ 0x43U, 1U, 0x80UL, 0x80UL },	/* port 1 */
42 	};
43 	struct ata_port *ap = link->ap;
44 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
45 
46 	if (!pci_test_config_bits(pdev, &efar_enable_bits[ap->port_no]))
47 		return -ENOENT;
48 
49 	return ata_sff_prereset(link, deadline);
50 }
51 
52 /**
53  *	efar_cable_detect	-	check for 40/80 pin
54  *	@ap: Port
55  *
56  *	Perform cable detection for the EFAR ATA interface. This is
57  *	different to the PIIX arrangement
58  */
59 
60 static int efar_cable_detect(struct ata_port *ap)
61 {
62 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
63 	u8 tmp;
64 
65 	pci_read_config_byte(pdev, 0x47, &tmp);
66 	if (tmp & (2 >> ap->port_no))
67 		return ATA_CBL_PATA40;
68 	return ATA_CBL_PATA80;
69 }
70 
71 static DEFINE_SPINLOCK(efar_lock);
72 
73 /**
74  *	efar_set_piomode - Initialize host controller PATA PIO timings
75  *	@ap: Port whose timings we are configuring
76  *	@adev: Device to program
77  *
78  *	Set PIO mode for device, in host controller PCI config space.
79  *
80  *	LOCKING:
81  *	None (inherited from caller).
82  */
83 
84 static void efar_set_piomode (struct ata_port *ap, struct ata_device *adev)
85 {
86 	unsigned int pio	= adev->pio_mode - XFER_PIO_0;
87 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
88 	unsigned int master_port = ap->port_no ? 0x42 : 0x40;
89 	unsigned long flags;
90 	u16 master_data;
91 	u8 udma_enable;
92 	int control = 0;
93 
94 	/*
95 	 *	See Intel Document 298600-004 for the timing programing rules
96 	 *	for PIIX/ICH. The EFAR is a clone so very similar
97 	 */
98 
99 	static const	 /* ISP  RTC */
100 	u8 timings[][2]	= { { 0, 0 },
101 			    { 0, 0 },
102 			    { 1, 0 },
103 			    { 2, 1 },
104 			    { 2, 3 }, };
105 
106 	if (pio > 1)
107 		control |= 1;	/* TIME */
108 	if (ata_pio_need_iordy(adev))	/* PIO 3/4 require IORDY */
109 		control |= 2;	/* IE */
110 	/* Intel specifies that the prefetch/posting is for disk only */
111 	if (adev->class == ATA_DEV_ATA)
112 		control |= 4;	/* PPE */
113 
114 	spin_lock_irqsave(&efar_lock, flags);
115 
116 	pci_read_config_word(dev, master_port, &master_data);
117 
118 	/* Set PPE, IE, and TIME as appropriate */
119 	if (adev->devno == 0) {
120 		master_data &= 0xCCF0;
121 		master_data |= control;
122 		master_data |= (timings[pio][0] << 12) |
123 			(timings[pio][1] << 8);
124 	} else {
125 		int shift = 4 * ap->port_no;
126 		u8 slave_data;
127 
128 		master_data &= 0xFF0F;
129 		master_data |= (control << 4);
130 
131 		/* Slave timing in separate register */
132 		pci_read_config_byte(dev, 0x44, &slave_data);
133 		slave_data &= ap->port_no ? 0x0F : 0xF0;
134 		slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << shift;
135 		pci_write_config_byte(dev, 0x44, slave_data);
136 	}
137 
138 	master_data |= 0x4000;	/* Ensure SITRE is set */
139 	pci_write_config_word(dev, master_port, master_data);
140 
141 	pci_read_config_byte(dev, 0x48, &udma_enable);
142 	udma_enable &= ~(1 << (2 * ap->port_no + adev->devno));
143 	pci_write_config_byte(dev, 0x48, udma_enable);
144 	spin_unlock_irqrestore(&efar_lock, flags);
145 }
146 
147 /**
148  *	efar_set_dmamode - Initialize host controller PATA DMA timings
149  *	@ap: Port whose timings we are configuring
150  *	@adev: Device to program
151  *
152  *	Set UDMA/MWDMA mode for device, in host controller PCI config space.
153  *
154  *	LOCKING:
155  *	None (inherited from caller).
156  */
157 
158 static void efar_set_dmamode (struct ata_port *ap, struct ata_device *adev)
159 {
160 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
161 	u8 master_port		= ap->port_no ? 0x42 : 0x40;
162 	u16 master_data;
163 	u8 speed		= adev->dma_mode;
164 	int devid		= adev->devno + 2 * ap->port_no;
165 	unsigned long flags;
166 	u8 udma_enable;
167 
168 	static const	 /* ISP  RTC */
169 	u8 timings[][2]	= { { 0, 0 },
170 			    { 0, 0 },
171 			    { 1, 0 },
172 			    { 2, 1 },
173 			    { 2, 3 }, };
174 
175 	spin_lock_irqsave(&efar_lock, flags);
176 
177 	pci_read_config_word(dev, master_port, &master_data);
178 	pci_read_config_byte(dev, 0x48, &udma_enable);
179 
180 	if (speed >= XFER_UDMA_0) {
181 		unsigned int udma	= adev->dma_mode - XFER_UDMA_0;
182 		u16 udma_timing;
183 
184 		udma_enable |= (1 << devid);
185 
186 		/* Load the UDMA mode number */
187 		pci_read_config_word(dev, 0x4A, &udma_timing);
188 		udma_timing &= ~(7 << (4 * devid));
189 		udma_timing |= udma << (4 * devid);
190 		pci_write_config_word(dev, 0x4A, udma_timing);
191 	} else {
192 		/*
193 		 * MWDMA is driven by the PIO timings. We must also enable
194 		 * IORDY unconditionally along with TIME1. PPE has already
195 		 * been set when the PIO timing was set.
196 		 */
197 		unsigned int mwdma	= adev->dma_mode - XFER_MW_DMA_0;
198 		unsigned int control;
199 		u8 slave_data;
200 		const unsigned int needed_pio[3] = {
201 			XFER_PIO_0, XFER_PIO_3, XFER_PIO_4
202 		};
203 		int pio = needed_pio[mwdma] - XFER_PIO_0;
204 
205 		control = 3;	/* IORDY|TIME1 */
206 
207 		/* If the drive MWDMA is faster than it can do PIO then
208 		   we must force PIO into PIO0 */
209 
210 		if (adev->pio_mode < needed_pio[mwdma])
211 			/* Enable DMA timing only */
212 			control |= 8;	/* PIO cycles in PIO0 */
213 
214 		if (adev->devno) {	/* Slave */
215 			master_data &= 0xFF4F;  /* Mask out IORDY|TIME1|DMAONLY */
216 			master_data |= control << 4;
217 			pci_read_config_byte(dev, 0x44, &slave_data);
218 			slave_data &= ap->port_no ? 0x0F : 0xF0;
219 			/* Load the matching timing */
220 			slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << (ap->port_no ? 4 : 0);
221 			pci_write_config_byte(dev, 0x44, slave_data);
222 		} else { 	/* Master */
223 			master_data &= 0xCCF4;	/* Mask out IORDY|TIME1|DMAONLY
224 						   and master timing bits */
225 			master_data |= control;
226 			master_data |=
227 				(timings[pio][0] << 12) |
228 				(timings[pio][1] << 8);
229 		}
230 		udma_enable &= ~(1 << devid);
231 		pci_write_config_word(dev, master_port, master_data);
232 	}
233 	pci_write_config_byte(dev, 0x48, udma_enable);
234 	spin_unlock_irqrestore(&efar_lock, flags);
235 }
236 
237 static const struct scsi_host_template efar_sht = {
238 	ATA_BMDMA_SHT(DRV_NAME),
239 };
240 
241 static struct ata_port_operations efar_ops = {
242 	.inherits		= &ata_bmdma_port_ops,
243 	.cable_detect		= efar_cable_detect,
244 	.set_piomode		= efar_set_piomode,
245 	.set_dmamode		= efar_set_dmamode,
246 	.prereset		= efar_pre_reset,
247 };
248 
249 
250 /**
251  *	efar_init_one - Register EFAR ATA PCI device with kernel services
252  *	@pdev: PCI device to register
253  *	@ent: Entry in efar_pci_tbl matching with @pdev
254  *
255  *	Called from kernel PCI layer.
256  *
257  *	LOCKING:
258  *	Inherited from PCI layer (may sleep).
259  *
260  *	RETURNS:
261  *	Zero on success, or -ERRNO value.
262  */
263 
264 static int efar_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
265 {
266 	static const struct ata_port_info info = {
267 		.flags		= ATA_FLAG_SLAVE_POSS,
268 		.pio_mask	= ATA_PIO4,
269 		.mwdma_mask	= ATA_MWDMA12_ONLY,
270 		.udma_mask 	= ATA_UDMA4,
271 		.port_ops	= &efar_ops,
272 	};
273 	const struct ata_port_info *ppi[] = { &info, &info };
274 
275 	ata_print_version_once(&pdev->dev, DRV_VERSION);
276 
277 	return ata_pci_bmdma_init_one(pdev, ppi, &efar_sht, NULL,
278 				      ATA_HOST_PARALLEL_SCAN);
279 }
280 
281 static const struct pci_device_id efar_pci_tbl[] = {
282 	{ PCI_VDEVICE(EFAR, 0x9130), },
283 
284 	{ }	/* terminate list */
285 };
286 
287 static struct pci_driver efar_pci_driver = {
288 	.name			= DRV_NAME,
289 	.id_table		= efar_pci_tbl,
290 	.probe			= efar_init_one,
291 	.remove			= ata_pci_remove_one,
292 #ifdef CONFIG_PM_SLEEP
293 	.suspend		= ata_pci_device_suspend,
294 	.resume			= ata_pci_device_resume,
295 #endif
296 };
297 
298 module_pci_driver(efar_pci_driver);
299 
300 MODULE_AUTHOR("Alan Cox");
301 MODULE_DESCRIPTION("SCSI low-level driver for EFAR PIIX clones");
302 MODULE_LICENSE("GPL");
303 MODULE_DEVICE_TABLE(pci, efar_pci_tbl);
304 MODULE_VERSION(DRV_VERSION);
305