xref: /openbmc/linux/drivers/ata/pata_sch.c (revision cfbb9be8)
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/blkdev.h>
31 #include <linux/delay.h>
32 #include <linux/device.h>
33 #include <scsi/scsi_host.h>
34 #include <linux/libata.h>
35 #include <linux/dmi.h>
36 
37 #define DRV_NAME	"pata_sch"
38 #define DRV_VERSION	"0.2"
39 
40 /* see SCH datasheet page 351 */
41 enum {
42 	D0TIM	= 0x80,		/* Device 0 Timing Register */
43 	D1TIM	= 0x84,		/* Device 1 Timing Register */
44 	PM	= 0x07,		/* PIO Mode Bit Mask */
45 	MDM	= (0x03 << 8),	/* Multi-word DMA Mode Bit Mask */
46 	UDM	= (0x07 << 16), /* Ultra DMA Mode Bit Mask */
47 	PPE	= (1 << 30),	/* Prefetch/Post Enable */
48 	USD	= (1 << 31),	/* Use Synchronous DMA */
49 };
50 
51 static int sch_init_one(struct pci_dev *pdev,
52 			 const struct pci_device_id *ent);
53 static void sch_set_piomode(struct ata_port *ap, struct ata_device *adev);
54 static void sch_set_dmamode(struct ata_port *ap, struct ata_device *adev);
55 
56 static const struct pci_device_id sch_pci_tbl[] = {
57 	/* Intel SCH PATA Controller */
58 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_SCH_IDE), 0 },
59 	{ }	/* terminate list */
60 };
61 
62 static struct pci_driver sch_pci_driver = {
63 	.name			= DRV_NAME,
64 	.id_table		= sch_pci_tbl,
65 	.probe			= sch_init_one,
66 	.remove			= ata_pci_remove_one,
67 #ifdef CONFIG_PM_SLEEP
68 	.suspend		= ata_pci_device_suspend,
69 	.resume			= ata_pci_device_resume,
70 #endif
71 };
72 
73 static struct scsi_host_template sch_sht = {
74 	ATA_BMDMA_SHT(DRV_NAME),
75 };
76 
77 static struct ata_port_operations sch_pata_ops = {
78 	.inherits		= &ata_bmdma_port_ops,
79 	.cable_detect		= ata_cable_unknown,
80 	.set_piomode		= sch_set_piomode,
81 	.set_dmamode		= sch_set_dmamode,
82 };
83 
84 static const struct ata_port_info sch_port_info = {
85 	.flags		= ATA_FLAG_SLAVE_POSS,
86 	.pio_mask	= ATA_PIO4,
87 	.mwdma_mask	= ATA_MWDMA2,
88 	.udma_mask	= ATA_UDMA5,
89 	.port_ops	= &sch_pata_ops,
90 };
91 
92 MODULE_AUTHOR("Alek Du <alek.du@intel.com>");
93 MODULE_DESCRIPTION("SCSI low-level driver for Intel SCH PATA controllers");
94 MODULE_LICENSE("GPL");
95 MODULE_DEVICE_TABLE(pci, sch_pci_tbl);
96 MODULE_VERSION(DRV_VERSION);
97 
98 /**
99  *	sch_set_piomode - Initialize host controller PATA PIO timings
100  *	@ap: Port whose timings we are configuring
101  *	@adev: ATA device
102  *
103  *	Set PIO mode for device, in host controller PCI config space.
104  *
105  *	LOCKING:
106  *	None (inherited from caller).
107  */
108 
109 static void sch_set_piomode(struct ata_port *ap, struct ata_device *adev)
110 {
111 	unsigned int pio	= adev->pio_mode - XFER_PIO_0;
112 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
113 	unsigned int port	= adev->devno ? D1TIM : D0TIM;
114 	unsigned int data;
115 
116 	pci_read_config_dword(dev, port, &data);
117 	/* see SCH datasheet page 351 */
118 	/* set PIO mode */
119 	data &= ~(PM | PPE);
120 	data |= pio;
121 	/* enable PPE for block device */
122 	if (adev->class == ATA_DEV_ATA)
123 		data |= PPE;
124 	pci_write_config_dword(dev, port, data);
125 }
126 
127 /**
128  *	sch_set_dmamode - Initialize host controller PATA DMA timings
129  *	@ap: Port whose timings we are configuring
130  *	@adev: ATA device
131  *
132  *	Set MW/UDMA mode for device, in host controller PCI config space.
133  *
134  *	LOCKING:
135  *	None (inherited from caller).
136  */
137 
138 static void sch_set_dmamode(struct ata_port *ap, struct ata_device *adev)
139 {
140 	unsigned int dma_mode	= adev->dma_mode;
141 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
142 	unsigned int port	= adev->devno ? D1TIM : D0TIM;
143 	unsigned int data;
144 
145 	pci_read_config_dword(dev, port, &data);
146 	/* see SCH datasheet page 351 */
147 	if (dma_mode >= XFER_UDMA_0) {
148 		/* enable Synchronous DMA mode */
149 		data |= USD;
150 		data &= ~UDM;
151 		data |= (dma_mode - XFER_UDMA_0) << 16;
152 	} else { /* must be MWDMA mode, since we masked SWDMA already */
153 		data &= ~(USD | MDM);
154 		data |= (dma_mode - XFER_MW_DMA_0) << 8;
155 	}
156 	pci_write_config_dword(dev, port, data);
157 }
158 
159 /**
160  *	sch_init_one - Register SCH ATA PCI device with kernel services
161  *	@pdev: PCI device to register
162  *	@ent: Entry in sch_pci_tbl matching with @pdev
163  *
164  *	LOCKING:
165  *	Inherited from PCI layer (may sleep).
166  *
167  *	RETURNS:
168  *	Zero on success, or -ERRNO value.
169  */
170 
171 static int sch_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
172 {
173 	const struct ata_port_info *ppi[] = { &sch_port_info, NULL };
174 
175 	ata_print_version_once(&pdev->dev, DRV_VERSION);
176 
177 	return ata_pci_bmdma_init_one(pdev, ppi, &sch_sht, NULL, 0);
178 }
179 
180 module_pci_driver(sch_pci_driver);
181