xref: /openbmc/linux/drivers/ata/pata_sch.c (revision 367b8112)
1 /*
2  *  pata_sch.c - Intel SCH PATA controllers
3  *
4  *  Copyright (c) 2008 Alek Du <alek.du@intel.com>
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License 2 as published
8  *  by the Free Software Foundation.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; see the file COPYING.  If not, write to
17  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
18  *
19  */
20 
21 /*
22  *  Supports:
23  *    Intel SCH (AF82US15W, AF82US15L, AF82UL11L) chipsets -- see spec at:
24  *    http://download.intel.com/design/chipsets/embedded/datashts/319537.pdf
25  */
26 
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/pci.h>
30 #include <linux/init.h>
31 #include <linux/blkdev.h>
32 #include <linux/delay.h>
33 #include <linux/device.h>
34 #include <scsi/scsi_host.h>
35 #include <linux/libata.h>
36 #include <linux/dmi.h>
37 
38 #define DRV_NAME	"pata_sch"
39 #define DRV_VERSION	"0.2"
40 
41 /* see SCH datasheet page 351 */
42 enum {
43 	D0TIM	= 0x80,		/* Device 0 Timing Register */
44 	D1TIM	= 0x84,		/* Device 1 Timing Register */
45 	PM	= 0x07,		/* PIO Mode Bit Mask */
46 	MDM	= (0x03 << 8),	/* Multi-word DMA Mode Bit Mask */
47 	UDM	= (0x07 << 16), /* Ultra DMA Mode Bit Mask */
48 	PPE	= (1 << 30),	/* Prefetch/Post Enable */
49 	USD	= (1 << 31),	/* Use Synchronous DMA */
50 };
51 
52 static int sch_init_one(struct pci_dev *pdev,
53 			 const struct pci_device_id *ent);
54 static void sch_set_piomode(struct ata_port *ap, struct ata_device *adev);
55 static void sch_set_dmamode(struct ata_port *ap, struct ata_device *adev);
56 
57 static const struct pci_device_id sch_pci_tbl[] = {
58 	/* Intel SCH PATA Controller */
59 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_SCH_IDE), 0 },
60 	{ }	/* terminate list */
61 };
62 
63 static struct pci_driver sch_pci_driver = {
64 	.name			= DRV_NAME,
65 	.id_table		= sch_pci_tbl,
66 	.probe			= sch_init_one,
67 	.remove			= ata_pci_remove_one,
68 #ifdef CONFIG_PM
69 	.suspend		= ata_pci_device_suspend,
70 	.resume			= ata_pci_device_resume,
71 #endif
72 };
73 
74 static struct scsi_host_template sch_sht = {
75 	ATA_BMDMA_SHT(DRV_NAME),
76 };
77 
78 static struct ata_port_operations sch_pata_ops = {
79 	.inherits		= &ata_bmdma_port_ops,
80 	.cable_detect		= ata_cable_unknown,
81 	.set_piomode		= sch_set_piomode,
82 	.set_dmamode		= sch_set_dmamode,
83 };
84 
85 static struct ata_port_info sch_port_info = {
86 	.flags		= 0,
87 	.pio_mask	= ATA_PIO4,   /* pio0-4 */
88 	.mwdma_mask	= ATA_MWDMA2, /* mwdma0-2 */
89 	.udma_mask	= ATA_UDMA5,  /* udma0-5 */
90 	.port_ops	= &sch_pata_ops,
91 };
92 
93 MODULE_AUTHOR("Alek Du <alek.du@intel.com>");
94 MODULE_DESCRIPTION("SCSI low-level driver for Intel SCH PATA controllers");
95 MODULE_LICENSE("GPL");
96 MODULE_DEVICE_TABLE(pci, sch_pci_tbl);
97 MODULE_VERSION(DRV_VERSION);
98 
99 /**
100  *	sch_set_piomode - Initialize host controller PATA PIO timings
101  *	@ap: Port whose timings we are configuring
102  *	@adev: ATA device
103  *
104  *	Set PIO mode for device, in host controller PCI config space.
105  *
106  *	LOCKING:
107  *	None (inherited from caller).
108  */
109 
110 static void sch_set_piomode(struct ata_port *ap, struct ata_device *adev)
111 {
112 	unsigned int pio	= adev->pio_mode - XFER_PIO_0;
113 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
114 	unsigned int port	= adev->devno ? D1TIM : D0TIM;
115 	unsigned int data;
116 
117 	pci_read_config_dword(dev, port, &data);
118 	/* see SCH datasheet page 351 */
119 	/* set PIO mode */
120 	data &= ~(PM | PPE);
121 	data |= pio;
122 	/* enable PPE for block device */
123 	if (adev->class == ATA_DEV_ATA)
124 		data |= PPE;
125 	pci_write_config_dword(dev, port, data);
126 }
127 
128 /**
129  *	sch_set_dmamode - Initialize host controller PATA DMA timings
130  *	@ap: Port whose timings we are configuring
131  *	@adev: ATA device
132  *
133  *	Set MW/UDMA mode for device, in host controller PCI config space.
134  *
135  *	LOCKING:
136  *	None (inherited from caller).
137  */
138 
139 static void sch_set_dmamode(struct ata_port *ap, struct ata_device *adev)
140 {
141 	unsigned int dma_mode	= adev->dma_mode;
142 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
143 	unsigned int port	= adev->devno ? D1TIM : D0TIM;
144 	unsigned int data;
145 
146 	pci_read_config_dword(dev, port, &data);
147 	/* see SCH datasheet page 351 */
148 	if (dma_mode >= XFER_UDMA_0) {
149 		/* enable Synchronous DMA mode */
150 		data |= USD;
151 		data &= ~UDM;
152 		data |= (dma_mode - XFER_UDMA_0) << 16;
153 	} else { /* must be MWDMA mode, since we masked SWDMA already */
154 		data &= ~(USD | MDM);
155 		data |= (dma_mode - XFER_MW_DMA_0) << 8;
156 	}
157 	pci_write_config_dword(dev, port, data);
158 }
159 
160 /**
161  *	sch_init_one - Register SCH ATA PCI device with kernel services
162  *	@pdev: PCI device to register
163  *	@ent: Entry in sch_pci_tbl matching with @pdev
164  *
165  *	LOCKING:
166  *	Inherited from PCI layer (may sleep).
167  *
168  *	RETURNS:
169  *	Zero on success, or -ERRNO value.
170  */
171 
172 static int __devinit sch_init_one(struct pci_dev *pdev,
173 				   const struct pci_device_id *ent)
174 {
175 	static int printed_version;
176 	const struct ata_port_info *ppi[] = { &sch_port_info, NULL };
177 	struct ata_host *host;
178 	int rc;
179 
180 	if (!printed_version++)
181 		dev_printk(KERN_DEBUG, &pdev->dev,
182 			   "version " DRV_VERSION "\n");
183 
184 	/* enable device and prepare host */
185 	rc = pcim_enable_device(pdev);
186 	if (rc)
187 		return rc;
188 	rc = ata_pci_sff_prepare_host(pdev, ppi, &host);
189 	if (rc)
190 		return rc;
191 	pci_set_master(pdev);
192 	return ata_pci_sff_activate_host(host, ata_sff_interrupt, &sch_sht);
193 }
194 
195 static int __init sch_init(void)
196 {
197 	return pci_register_driver(&sch_pci_driver);
198 }
199 
200 static void __exit sch_exit(void)
201 {
202 	pci_unregister_driver(&sch_pci_driver);
203 }
204 
205 module_init(sch_init);
206 module_exit(sch_exit);
207