xref: /openbmc/linux/drivers/ata/pata_mpiix.c (revision afb46f79)
1 /*
2  * pata_mpiix.c 	- Intel MPIIX PATA for new ATA layer
3  *			  (C) 2005-2006 Red Hat Inc
4  *			  Alan Cox <alan@lxorguk.ukuu.org.uk>
5  *
6  * The MPIIX is different enough to the PIIX4 and friends that we give it
7  * a separate driver. The old ide/pci code handles this by just not tuning
8  * MPIIX at all.
9  *
10  * The MPIIX also differs in another important way from the majority of PIIX
11  * devices. The chip is a bridge (pardon the pun) between the old world of
12  * ISA IDE and PCI IDE. Although the ATA timings are PCI configured the actual
13  * IDE controller is not decoded in PCI space and the chip does not claim to
14  * be IDE class PCI. This requires slightly non-standard probe logic compared
15  * with PCI IDE and also that we do not disable the device when our driver is
16  * unloaded (as it has many other functions).
17  *
18  * The driver consciously keeps this logic internally to avoid pushing quirky
19  * PATA history into the clean libata layer.
20  *
21  * Thinkpad specific note: If you boot an MPIIX using a thinkpad with a PCMCIA
22  * hard disk present this driver will not detect it. This is not a bug. In this
23  * configuration the secondary port of the MPIIX is disabled and the addresses
24  * are decoded by the PCMCIA bridge and therefore are for a generic IDE driver
25  * to operate.
26  */
27 
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/pci.h>
31 #include <linux/blkdev.h>
32 #include <linux/delay.h>
33 #include <scsi/scsi_host.h>
34 #include <linux/libata.h>
35 
36 #define DRV_NAME "pata_mpiix"
37 #define DRV_VERSION "0.7.7"
38 
39 enum {
40 	IDETIM = 0x6C,		/* IDE control register */
41 	IORDY = (1 << 1),
42 	PPE = (1 << 2),
43 	FTIM = (1 << 0),
44 	ENABLED = (1 << 15),
45 	SECONDARY = (1 << 14)
46 };
47 
48 static int mpiix_pre_reset(struct ata_link *link, unsigned long deadline)
49 {
50 	struct ata_port *ap = link->ap;
51 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
52 	static const struct pci_bits mpiix_enable_bits = { 0x6D, 1, 0x80, 0x80 };
53 
54 	if (!pci_test_config_bits(pdev, &mpiix_enable_bits))
55 		return -ENOENT;
56 
57 	return ata_sff_prereset(link, deadline);
58 }
59 
60 /**
61  *	mpiix_set_piomode	-	set initial PIO mode data
62  *	@ap: ATA interface
63  *	@adev: ATA device
64  *
65  *	Called to do the PIO mode setup. The MPIIX allows us to program the
66  *	IORDY sample point (2-5 clocks), recovery (1-4 clocks) and whether
67  *	prefetching or IORDY are used.
68  *
69  *	This would get very ugly because we can only program timing for one
70  *	device at a time, the other gets PIO0. Fortunately libata calls
71  *	our qc_issue command before a command is issued so we can flip the
72  *	timings back and forth to reduce the pain.
73  */
74 
75 static void mpiix_set_piomode(struct ata_port *ap, struct ata_device *adev)
76 {
77 	int control = 0;
78 	int pio = adev->pio_mode - XFER_PIO_0;
79 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
80 	u16 idetim;
81 	static const	 /* ISP  RTC */
82 	u8 timings[][2]	= { { 0, 0 },
83 			    { 0, 0 },
84 			    { 1, 0 },
85 			    { 2, 1 },
86 			    { 2, 3 }, };
87 
88 	pci_read_config_word(pdev, IDETIM, &idetim);
89 
90 	/* Mask the IORDY/TIME/PPE for this device */
91 	if (adev->class == ATA_DEV_ATA)
92 		control |= PPE;		/* Enable prefetch/posting for disk */
93 	if (ata_pio_need_iordy(adev))
94 		control |= IORDY;
95 	if (pio > 1)
96 		control |= FTIM;	/* This drive is on the fast timing bank */
97 
98 	/* Mask out timing and clear both TIME bank selects */
99 	idetim &= 0xCCEE;
100 	idetim &= ~(0x07  << (4 * adev->devno));
101 	idetim |= control << (4 * adev->devno);
102 
103 	idetim |= (timings[pio][0] << 12) | (timings[pio][1] << 8);
104 	pci_write_config_word(pdev, IDETIM, idetim);
105 
106 	/* We use ap->private_data as a pointer to the device currently
107 	   loaded for timing */
108 	ap->private_data = adev;
109 }
110 
111 /**
112  *	mpiix_qc_issue		-	command issue
113  *	@qc: command pending
114  *
115  *	Called when the libata layer is about to issue a command. We wrap
116  *	this interface so that we can load the correct ATA timings if
117  *	necessary. Our logic also clears TIME0/TIME1 for the other device so
118  *	that, even if we get this wrong, cycles to the other device will
119  *	be made PIO0.
120  */
121 
122 static unsigned int mpiix_qc_issue(struct ata_queued_cmd *qc)
123 {
124 	struct ata_port *ap = qc->ap;
125 	struct ata_device *adev = qc->dev;
126 
127 	/* If modes have been configured and the channel data is not loaded
128 	   then load it. We have to check if pio_mode is set as the core code
129 	   does not set adev->pio_mode to XFER_PIO_0 while probing as would be
130 	   logical */
131 
132 	if (adev->pio_mode && adev != ap->private_data)
133 		mpiix_set_piomode(ap, adev);
134 
135 	return ata_sff_qc_issue(qc);
136 }
137 
138 static struct scsi_host_template mpiix_sht = {
139 	ATA_PIO_SHT(DRV_NAME),
140 };
141 
142 static struct ata_port_operations mpiix_port_ops = {
143 	.inherits	= &ata_sff_port_ops,
144 	.qc_issue	= mpiix_qc_issue,
145 	.cable_detect	= ata_cable_40wire,
146 	.set_piomode	= mpiix_set_piomode,
147 	.prereset	= mpiix_pre_reset,
148 	.sff_data_xfer	= ata_sff_data_xfer32,
149 };
150 
151 static int mpiix_init_one(struct pci_dev *dev, const struct pci_device_id *id)
152 {
153 	/* Single threaded by the PCI probe logic */
154 	struct ata_host *host;
155 	struct ata_port *ap;
156 	void __iomem *cmd_addr, *ctl_addr;
157 	u16 idetim;
158 	int cmd, ctl, irq;
159 
160 	ata_print_version_once(&dev->dev, DRV_VERSION);
161 
162 	host = ata_host_alloc(&dev->dev, 1);
163 	if (!host)
164 		return -ENOMEM;
165 	ap = host->ports[0];
166 
167 	/* MPIIX has many functions which can be turned on or off according
168 	   to other devices present. Make sure IDE is enabled before we try
169 	   and use it */
170 
171 	pci_read_config_word(dev, IDETIM, &idetim);
172 	if (!(idetim & ENABLED))
173 		return -ENODEV;
174 
175 	/* See if it's primary or secondary channel... */
176 	if (!(idetim & SECONDARY)) {
177 		cmd = 0x1F0;
178 		ctl = 0x3F6;
179 		irq = 14;
180 	} else {
181 		cmd = 0x170;
182 		ctl = 0x376;
183 		irq = 15;
184 	}
185 
186 	cmd_addr = devm_ioport_map(&dev->dev, cmd, 8);
187 	ctl_addr = devm_ioport_map(&dev->dev, ctl, 1);
188 	if (!cmd_addr || !ctl_addr)
189 		return -ENOMEM;
190 
191 	ata_port_desc(ap, "cmd 0x%x ctl 0x%x", cmd, ctl);
192 
193 	/* We do our own plumbing to avoid leaking special cases for whacko
194 	   ancient hardware into the core code. There are two issues to
195 	   worry about.  #1 The chip is a bridge so if in legacy mode and
196 	   without BARs set fools the setup.  #2 If you pci_disable_device
197 	   the MPIIX your box goes castors up */
198 
199 	ap->ops = &mpiix_port_ops;
200 	ap->pio_mask = ATA_PIO4;
201 	ap->flags |= ATA_FLAG_SLAVE_POSS;
202 
203 	ap->ioaddr.cmd_addr = cmd_addr;
204 	ap->ioaddr.ctl_addr = ctl_addr;
205 	ap->ioaddr.altstatus_addr = ctl_addr;
206 
207 	/* Let libata fill in the port details */
208 	ata_sff_std_ports(&ap->ioaddr);
209 
210 	/* activate host */
211 	return ata_host_activate(host, irq, ata_sff_interrupt, IRQF_SHARED,
212 				 &mpiix_sht);
213 }
214 
215 static const struct pci_device_id mpiix[] = {
216 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_82371MX), },
217 
218 	{ },
219 };
220 
221 static struct pci_driver mpiix_pci_driver = {
222 	.name 		= DRV_NAME,
223 	.id_table	= mpiix,
224 	.probe 		= mpiix_init_one,
225 	.remove		= ata_pci_remove_one,
226 #ifdef CONFIG_PM
227 	.suspend	= ata_pci_device_suspend,
228 	.resume		= ata_pci_device_resume,
229 #endif
230 };
231 
232 module_pci_driver(mpiix_pci_driver);
233 
234 MODULE_AUTHOR("Alan Cox");
235 MODULE_DESCRIPTION("low-level driver for Intel MPIIX");
236 MODULE_LICENSE("GPL");
237 MODULE_DEVICE_TABLE(pci, mpiix);
238 MODULE_VERSION(DRV_VERSION);
239