xref: /openbmc/linux/drivers/ata/pata_sch.c (revision 9aa2cba7)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  pata_sch.c - Intel SCH PATA controllers
4  *
5  *  Copyright (c) 2008 Alek Du <alek.du@intel.com>
6  */
7 
8 /*
9  *  Supports:
10  *    Intel SCH (AF82US15W, AF82US15L, AF82UL11L) chipsets -- see spec at:
11  *    http://download.intel.com/design/chipsets/embedded/datashts/319537.pdf
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/dmi.h>
23 
24 #define DRV_NAME	"pata_sch"
25 #define DRV_VERSION	"0.2"
26 
27 /* see SCH datasheet page 351 */
28 enum {
29 	D0TIM	= 0x80,		/* Device 0 Timing Register */
30 	D1TIM	= 0x84,		/* Device 1 Timing Register */
31 	PM	= 0x07,		/* PIO Mode Bit Mask */
32 	MDM	= (0x03 << 8),	/* Multi-word DMA Mode Bit Mask */
33 	UDM	= (0x07 << 16), /* Ultra DMA Mode Bit Mask */
34 	PPE	= (1 << 30),	/* Prefetch/Post Enable */
35 	USD	= (1 << 31),	/* Use Synchronous DMA */
36 };
37 
38 static int sch_init_one(struct pci_dev *pdev,
39 			 const struct pci_device_id *ent);
40 static void sch_set_piomode(struct ata_port *ap, struct ata_device *adev);
41 static void sch_set_dmamode(struct ata_port *ap, struct ata_device *adev);
42 
43 static const struct pci_device_id sch_pci_tbl[] = {
44 	/* Intel SCH PATA Controller */
45 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_SCH_IDE), 0 },
46 	{ }	/* terminate list */
47 };
48 
49 static struct pci_driver sch_pci_driver = {
50 	.name			= DRV_NAME,
51 	.id_table		= sch_pci_tbl,
52 	.probe			= sch_init_one,
53 	.remove			= ata_pci_remove_one,
54 #ifdef CONFIG_PM_SLEEP
55 	.suspend		= ata_pci_device_suspend,
56 	.resume			= ata_pci_device_resume,
57 #endif
58 };
59 
60 static const struct scsi_host_template sch_sht = {
61 	ATA_BMDMA_SHT(DRV_NAME),
62 };
63 
64 static struct ata_port_operations sch_pata_ops = {
65 	.inherits		= &ata_bmdma_port_ops,
66 	.cable_detect		= ata_cable_unknown,
67 	.set_piomode		= sch_set_piomode,
68 	.set_dmamode		= sch_set_dmamode,
69 };
70 
71 static const struct ata_port_info sch_port_info = {
72 	.flags		= ATA_FLAG_SLAVE_POSS,
73 	.pio_mask	= ATA_PIO4,
74 	.mwdma_mask	= ATA_MWDMA2,
75 	.udma_mask	= ATA_UDMA5,
76 	.port_ops	= &sch_pata_ops,
77 };
78 
79 MODULE_AUTHOR("Alek Du <alek.du@intel.com>");
80 MODULE_DESCRIPTION("SCSI low-level driver for Intel SCH PATA controllers");
81 MODULE_LICENSE("GPL");
82 MODULE_DEVICE_TABLE(pci, sch_pci_tbl);
83 MODULE_VERSION(DRV_VERSION);
84 
85 /**
86  *	sch_set_piomode - Initialize host controller PATA PIO timings
87  *	@ap: Port whose timings we are configuring
88  *	@adev: ATA device
89  *
90  *	Set PIO mode for device, in host controller PCI config space.
91  *
92  *	LOCKING:
93  *	None (inherited from caller).
94  */
95 
96 static void sch_set_piomode(struct ata_port *ap, struct ata_device *adev)
97 {
98 	unsigned int pio	= adev->pio_mode - XFER_PIO_0;
99 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
100 	unsigned int port	= adev->devno ? D1TIM : D0TIM;
101 	unsigned int data;
102 
103 	pci_read_config_dword(dev, port, &data);
104 	/* see SCH datasheet page 351 */
105 	/* set PIO mode */
106 	data &= ~(PM | PPE);
107 	data |= pio;
108 	/* enable PPE for block device */
109 	if (adev->class == ATA_DEV_ATA)
110 		data |= PPE;
111 	pci_write_config_dword(dev, port, data);
112 }
113 
114 /**
115  *	sch_set_dmamode - Initialize host controller PATA DMA timings
116  *	@ap: Port whose timings we are configuring
117  *	@adev: ATA device
118  *
119  *	Set MW/UDMA mode for device, in host controller PCI config space.
120  *
121  *	LOCKING:
122  *	None (inherited from caller).
123  */
124 
125 static void sch_set_dmamode(struct ata_port *ap, struct ata_device *adev)
126 {
127 	unsigned int dma_mode	= adev->dma_mode;
128 	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
129 	unsigned int port	= adev->devno ? D1TIM : D0TIM;
130 	unsigned int data;
131 
132 	pci_read_config_dword(dev, port, &data);
133 	/* see SCH datasheet page 351 */
134 	if (dma_mode >= XFER_UDMA_0) {
135 		/* enable Synchronous DMA mode */
136 		data |= USD;
137 		data &= ~UDM;
138 		data |= (dma_mode - XFER_UDMA_0) << 16;
139 	} else { /* must be MWDMA mode, since we masked SWDMA already */
140 		data &= ~(USD | MDM);
141 		data |= (dma_mode - XFER_MW_DMA_0) << 8;
142 	}
143 	pci_write_config_dword(dev, port, data);
144 }
145 
146 /**
147  *	sch_init_one - Register SCH ATA PCI device with kernel services
148  *	@pdev: PCI device to register
149  *	@ent: Entry in sch_pci_tbl matching with @pdev
150  *
151  *	LOCKING:
152  *	Inherited from PCI layer (may sleep).
153  *
154  *	RETURNS:
155  *	Zero on success, or -ERRNO value.
156  */
157 
158 static int sch_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
159 {
160 	const struct ata_port_info *ppi[] = { &sch_port_info, NULL };
161 
162 	ata_print_version_once(&pdev->dev, DRV_VERSION);
163 
164 	return ata_pci_bmdma_init_one(pdev, ppi, &sch_sht, NULL, 0);
165 }
166 
167 module_pci_driver(sch_pci_driver);
168