xref: /openbmc/linux/drivers/ata/pata_radisys.c (revision 6d99a79c)
1 /*
2  *    pata_radisys.c - Intel PATA/SATA controllers
3  *
4  *	(C) 2006 Red Hat <alan@lxorguk.ukuu.org.uk>
5  *
6  *    Some parts based on ata_piix.c by Jeff Garzik and others.
7  *
8  *    A PIIX relative, this device has a single ATA channel and no
9  *    slave timings, SITRE or PPE. In that sense it is a close relative
10  *    of the original PIIX. It does however support UDMA 33/66 per channel
11  *    although no other modes/timings. Also lacking is 32bit I/O on the ATA
12  *    port.
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_radisys"
26 #define DRV_VERSION	"0.4.4"
27 
28 /**
29  *	radisys_set_piomode - Initialize host controller PATA PIO timings
30  *	@ap: ATA port
31  *	@adev: Device whose timings we are configuring
32  *
33  *	Set PIO mode for device, in host controller PCI config space.
34  *
35  *	LOCKING:
36  *	None (inherited from caller).
37  */
38 
39 static void radisys_set_piomode (struct ata_port *ap, struct ata_device *adev)
40 {
41 	unsigned int pio	= adev->pio_mode - XFER_PIO_0;
42 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
43 	u16 idetm_data;
44 	int control = 0;
45 
46 	/*
47 	 *	See Intel Document 298600-004 for the timing programing rules
48 	 *	for PIIX/ICH. Note that the early PIIX does not have the slave
49 	 *	timing port at 0x44. The Radisys is a relative of the PIIX
50 	 *	but not the same so be careful.
51 	 */
52 
53 	static const	 /* ISP  RTC */
54 	u8 timings[][2]	= { { 0, 0 },	/* Check me */
55 			    { 0, 0 },
56 			    { 1, 1 },
57 			    { 2, 2 },
58 			    { 3, 3 }, };
59 
60 	if (pio > 0)
61 		control |= 1;	/* TIME1 enable */
62 	if (ata_pio_need_iordy(adev))
63 		control |= 2;	/* IE IORDY */
64 
65 	pci_read_config_word(dev, 0x40, &idetm_data);
66 
67 	/* Enable IE and TIME as appropriate. Clear the other
68 	   drive timing bits */
69 	idetm_data &= 0xCCCC;
70 	idetm_data |= (control << (4 * adev->devno));
71 	idetm_data |= (timings[pio][0] << 12) |
72 			(timings[pio][1] << 8);
73 	pci_write_config_word(dev, 0x40, idetm_data);
74 
75 	/* Track which port is configured */
76 	ap->private_data = adev;
77 }
78 
79 /**
80  *	radisys_set_dmamode - Initialize host controller PATA DMA timings
81  *	@ap: Port whose timings we are configuring
82  *	@adev: Device to program
83  *
84  *	Set MWDMA mode for device, in host controller PCI config space.
85  *
86  *	LOCKING:
87  *	None (inherited from caller).
88  */
89 
90 static void radisys_set_dmamode (struct ata_port *ap, struct ata_device *adev)
91 {
92 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
93 	u16 idetm_data;
94 	u8 udma_enable;
95 
96 	static const	 /* ISP  RTC */
97 	u8 timings[][2]	= { { 0, 0 },
98 			    { 0, 0 },
99 			    { 1, 1 },
100 			    { 2, 2 },
101 			    { 3, 3 }, };
102 
103 	/*
104 	 * MWDMA is driven by the PIO timings. We must also enable
105 	 * IORDY unconditionally.
106 	 */
107 
108 	pci_read_config_word(dev, 0x40, &idetm_data);
109 	pci_read_config_byte(dev, 0x48, &udma_enable);
110 
111 	if (adev->dma_mode < XFER_UDMA_0) {
112 		unsigned int mwdma	= adev->dma_mode - XFER_MW_DMA_0;
113 		const unsigned int needed_pio[3] = {
114 			XFER_PIO_0, XFER_PIO_3, XFER_PIO_4
115 		};
116 		int pio = needed_pio[mwdma] - XFER_PIO_0;
117 		int control = 3;	/* IORDY|TIME0 */
118 
119 		/* If the drive MWDMA is faster than it can do PIO then
120 		   we must force PIO0 for PIO cycles. */
121 
122 		if (adev->pio_mode < needed_pio[mwdma])
123 			control = 1;
124 
125 		/* Mask out the relevant control and timing bits we will load. Also
126 		   clear the other drive TIME register as a precaution */
127 
128 		idetm_data &= 0xCCCC;
129 		idetm_data |= control << (4 * adev->devno);
130 		idetm_data |= (timings[pio][0] << 12) | (timings[pio][1] << 8);
131 
132 		udma_enable &= ~(1 << adev->devno);
133 	} else {
134 		u8 udma_mode;
135 
136 		/* UDMA66 on: UDMA 33 and 66 are switchable via register 0x4A */
137 
138 		pci_read_config_byte(dev, 0x4A, &udma_mode);
139 
140 		if (adev->xfer_mode == XFER_UDMA_2)
141 			udma_mode &= ~(2 << (adev->devno * 4));
142 		else /* UDMA 4 */
143 			udma_mode |= (2 << (adev->devno * 4));
144 
145 		pci_write_config_byte(dev, 0x4A, udma_mode);
146 
147 		udma_enable |= (1 << adev->devno);
148 	}
149 	pci_write_config_word(dev, 0x40, idetm_data);
150 	pci_write_config_byte(dev, 0x48, udma_enable);
151 
152 	/* Track which port is configured */
153 	ap->private_data = adev;
154 }
155 
156 /**
157  *	radisys_qc_issue	-	command issue
158  *	@qc: command pending
159  *
160  *	Called when the libata layer is about to issue a command. We wrap
161  *	this interface so that we can load the correct ATA timings if
162  *	necessary. Our logic also clears TIME0/TIME1 for the other device so
163  *	that, even if we get this wrong, cycles to the other device will
164  *	be made PIO0.
165  */
166 
167 static unsigned int radisys_qc_issue(struct ata_queued_cmd *qc)
168 {
169 	struct ata_port *ap = qc->ap;
170 	struct ata_device *adev = qc->dev;
171 
172 	if (adev != ap->private_data) {
173 		/* UDMA timing is not shared */
174 		if (adev->dma_mode < XFER_UDMA_0) {
175 			if (adev->dma_mode)
176 				radisys_set_dmamode(ap, adev);
177 			else if (adev->pio_mode)
178 				radisys_set_piomode(ap, adev);
179 		}
180 	}
181 	return ata_bmdma_qc_issue(qc);
182 }
183 
184 
185 static struct scsi_host_template radisys_sht = {
186 	ATA_BMDMA_SHT(DRV_NAME),
187 };
188 
189 static struct ata_port_operations radisys_pata_ops = {
190 	.inherits		= &ata_bmdma_port_ops,
191 	.qc_issue		= radisys_qc_issue,
192 	.cable_detect		= ata_cable_unknown,
193 	.set_piomode		= radisys_set_piomode,
194 	.set_dmamode		= radisys_set_dmamode,
195 };
196 
197 
198 /**
199  *	radisys_init_one - Register PIIX ATA PCI device with kernel services
200  *	@pdev: PCI device to register
201  *	@ent: Entry in radisys_pci_tbl matching with @pdev
202  *
203  *	Called from kernel PCI layer.  We probe for combined mode (sigh),
204  *	and then hand over control to libata, for it to do the rest.
205  *
206  *	LOCKING:
207  *	Inherited from PCI layer (may sleep).
208  *
209  *	RETURNS:
210  *	Zero on success, or -ERRNO value.
211  */
212 
213 static int radisys_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
214 {
215 	static const struct ata_port_info info = {
216 		.flags		= ATA_FLAG_SLAVE_POSS,
217 		.pio_mask	= ATA_PIO4,
218 		.mwdma_mask	= ATA_MWDMA12_ONLY,
219 		.udma_mask	= ATA_UDMA24_ONLY,
220 		.port_ops	= &radisys_pata_ops,
221 	};
222 	const struct ata_port_info *ppi[] = { &info, NULL };
223 
224 	ata_print_version_once(&pdev->dev, DRV_VERSION);
225 
226 	return ata_pci_bmdma_init_one(pdev, ppi, &radisys_sht, NULL, 0);
227 }
228 
229 static const struct pci_device_id radisys_pci_tbl[] = {
230 	{ PCI_VDEVICE(RADISYS, 0x8201), },
231 
232 	{ }	/* terminate list */
233 };
234 
235 static struct pci_driver radisys_pci_driver = {
236 	.name			= DRV_NAME,
237 	.id_table		= radisys_pci_tbl,
238 	.probe			= radisys_init_one,
239 	.remove			= ata_pci_remove_one,
240 #ifdef CONFIG_PM_SLEEP
241 	.suspend		= ata_pci_device_suspend,
242 	.resume			= ata_pci_device_resume,
243 #endif
244 };
245 
246 module_pci_driver(radisys_pci_driver);
247 
248 MODULE_AUTHOR("Alan Cox");
249 MODULE_DESCRIPTION("SCSI low-level driver for Radisys R82600 controllers");
250 MODULE_LICENSE("GPL");
251 MODULE_DEVICE_TABLE(pci, radisys_pci_tbl);
252 MODULE_VERSION(DRV_VERSION);
253