xref: /openbmc/linux/drivers/ata/pata_mpiix.c (revision 9b93eb47)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * pata_mpiix.c 	- Intel MPIIX PATA for new ATA layer
4  *			  (C) 2005-2006 Red Hat Inc
5  *			  Alan Cox <alan@lxorguk.ukuu.org.uk>
6  *
7  * The MPIIX is different enough to the PIIX4 and friends that we give it
8  * a separate driver. The old ide/pci code handles this by just not tuning
9  * MPIIX at all.
10  *
11  * The MPIIX also differs in another important way from the majority of PIIX
12  * devices. The chip is a bridge (pardon the pun) between the old world of
13  * ISA IDE and PCI IDE. Although the ATA timings are PCI configured the actual
14  * IDE controller is not decoded in PCI space and the chip does not claim to
15  * be IDE class PCI. This requires slightly non-standard probe logic compared
16  * with PCI IDE and also that we do not disable the device when our driver is
17  * unloaded (as it has many other functions).
18  *
19  * The driver consciously keeps this logic internally to avoid pushing quirky
20  * PATA history into the clean libata layer.
21  *
22  * Thinkpad specific note: If you boot an MPIIX using a thinkpad with a PCMCIA
23  * hard disk present this driver will not detect it. This is not a bug. In this
24  * configuration the secondary port of the MPIIX is disabled and the addresses
25  * are decoded by the PCMCIA bridge and therefore are for a generic IDE driver
26  * to operate.
27  */
28 
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/pci.h>
32 #include <linux/blkdev.h>
33 #include <linux/delay.h>
34 #include <scsi/scsi_host.h>
35 #include <linux/libata.h>
36 
37 #define DRV_NAME "pata_mpiix"
38 #define DRV_VERSION "0.7.7"
39 
40 enum {
41 	IDETIM = 0x6C,		/* IDE control register */
42 	IORDY = (1 << 1),
43 	PPE = (1 << 2),
44 	FTIM = (1 << 0),
45 	ENABLED = (1 << 15),
46 	SECONDARY = (1 << 14)
47 };
48 
49 static int mpiix_pre_reset(struct ata_link *link, unsigned long deadline)
50 {
51 	struct ata_port *ap = link->ap;
52 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
53 	static const struct pci_bits mpiix_enable_bits = { 0x6D, 1, 0x80, 0x80 };
54 
55 	if (!pci_test_config_bits(pdev, &mpiix_enable_bits))
56 		return -ENOENT;
57 
58 	return ata_sff_prereset(link, deadline);
59 }
60 
61 /**
62  *	mpiix_set_piomode	-	set initial PIO mode data
63  *	@ap: ATA interface
64  *	@adev: ATA device
65  *
66  *	Called to do the PIO mode setup. The MPIIX allows us to program the
67  *	IORDY sample point (2-5 clocks), recovery (1-4 clocks) and whether
68  *	prefetching or IORDY are used.
69  *
70  *	This would get very ugly because we can only program timing for one
71  *	device at a time, the other gets PIO0. Fortunately libata calls
72  *	our qc_issue command before a command is issued so we can flip the
73  *	timings back and forth to reduce the pain.
74  */
75 
76 static void mpiix_set_piomode(struct ata_port *ap, struct ata_device *adev)
77 {
78 	int control = 0;
79 	int pio = adev->pio_mode - XFER_PIO_0;
80 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
81 	u16 idetim;
82 	static const	 /* ISP  RTC */
83 	u8 timings[][2]	= { { 0, 0 },
84 			    { 0, 0 },
85 			    { 1, 0 },
86 			    { 2, 1 },
87 			    { 2, 3 }, };
88 
89 	pci_read_config_word(pdev, IDETIM, &idetim);
90 
91 	/* Mask the IORDY/TIME/PPE for this device */
92 	if (adev->class == ATA_DEV_ATA)
93 		control |= PPE;		/* Enable prefetch/posting for disk */
94 	if (ata_pio_need_iordy(adev))
95 		control |= IORDY;
96 	if (pio > 1)
97 		control |= FTIM;	/* This drive is on the fast timing bank */
98 
99 	/* Mask out timing and clear both TIME bank selects */
100 	idetim &= 0xCCEE;
101 	idetim &= ~(0x07  << (4 * adev->devno));
102 	idetim |= control << (4 * adev->devno);
103 
104 	idetim |= (timings[pio][0] << 12) | (timings[pio][1] << 8);
105 	pci_write_config_word(pdev, IDETIM, idetim);
106 
107 	/* We use ap->private_data as a pointer to the device currently
108 	   loaded for timing */
109 	ap->private_data = adev;
110 }
111 
112 /**
113  *	mpiix_qc_issue		-	command issue
114  *	@qc: command pending
115  *
116  *	Called when the libata layer is about to issue a command. We wrap
117  *	this interface so that we can load the correct ATA timings if
118  *	necessary. Our logic also clears TIME0/TIME1 for the other device so
119  *	that, even if we get this wrong, cycles to the other device will
120  *	be made PIO0.
121  */
122 
123 static unsigned int mpiix_qc_issue(struct ata_queued_cmd *qc)
124 {
125 	struct ata_port *ap = qc->ap;
126 	struct ata_device *adev = qc->dev;
127 
128 	/* If modes have been configured and the channel data is not loaded
129 	   then load it. We have to check if pio_mode is set as the core code
130 	   does not set adev->pio_mode to XFER_PIO_0 while probing as would be
131 	   logical */
132 
133 	if (adev->pio_mode && adev != ap->private_data)
134 		mpiix_set_piomode(ap, adev);
135 
136 	return ata_sff_qc_issue(qc);
137 }
138 
139 static struct scsi_host_template mpiix_sht = {
140 	ATA_PIO_SHT(DRV_NAME),
141 };
142 
143 static struct ata_port_operations mpiix_port_ops = {
144 	.inherits	= &ata_sff_port_ops,
145 	.qc_issue	= mpiix_qc_issue,
146 	.cable_detect	= ata_cable_40wire,
147 	.set_piomode	= mpiix_set_piomode,
148 	.prereset	= mpiix_pre_reset,
149 	.sff_data_xfer	= ata_sff_data_xfer32,
150 };
151 
152 static int mpiix_init_one(struct pci_dev *dev, const struct pci_device_id *id)
153 {
154 	/* Single threaded by the PCI probe logic */
155 	struct ata_host *host;
156 	struct ata_port *ap;
157 	void __iomem *cmd_addr, *ctl_addr;
158 	u16 idetim;
159 	int cmd, ctl, irq;
160 
161 	ata_print_version_once(&dev->dev, DRV_VERSION);
162 
163 	host = ata_host_alloc(&dev->dev, 1);
164 	if (!host)
165 		return -ENOMEM;
166 	ap = host->ports[0];
167 
168 	/* MPIIX has many functions which can be turned on or off according
169 	   to other devices present. Make sure IDE is enabled before we try
170 	   and use it */
171 
172 	pci_read_config_word(dev, IDETIM, &idetim);
173 	if (!(idetim & ENABLED))
174 		return -ENODEV;
175 
176 	/* See if it's primary or secondary channel... */
177 	if (!(idetim & SECONDARY)) {
178 		cmd = 0x1F0;
179 		ctl = 0x3F6;
180 		irq = 14;
181 	} else {
182 		cmd = 0x170;
183 		ctl = 0x376;
184 		irq = 15;
185 	}
186 
187 	cmd_addr = devm_ioport_map(&dev->dev, cmd, 8);
188 	ctl_addr = devm_ioport_map(&dev->dev, ctl, 1);
189 	if (!cmd_addr || !ctl_addr)
190 		return -ENOMEM;
191 
192 	ata_port_desc(ap, "cmd 0x%x ctl 0x%x", cmd, ctl);
193 
194 	/* We do our own plumbing to avoid leaking special cases for whacko
195 	   ancient hardware into the core code. There are two issues to
196 	   worry about.  #1 The chip is a bridge so if in legacy mode and
197 	   without BARs set fools the setup.  #2 If you pci_disable_device
198 	   the MPIIX your box goes castors up */
199 
200 	ap->ops = &mpiix_port_ops;
201 	ap->pio_mask = ATA_PIO4;
202 	ap->flags |= ATA_FLAG_SLAVE_POSS;
203 
204 	ap->ioaddr.cmd_addr = cmd_addr;
205 	ap->ioaddr.ctl_addr = ctl_addr;
206 	ap->ioaddr.altstatus_addr = ctl_addr;
207 
208 	/* Let libata fill in the port details */
209 	ata_sff_std_ports(&ap->ioaddr);
210 
211 	/* activate host */
212 	return ata_host_activate(host, irq, ata_sff_interrupt, IRQF_SHARED,
213 				 &mpiix_sht);
214 }
215 
216 static const struct pci_device_id mpiix[] = {
217 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_82371MX), },
218 
219 	{ },
220 };
221 
222 static struct pci_driver mpiix_pci_driver = {
223 	.name 		= DRV_NAME,
224 	.id_table	= mpiix,
225 	.probe 		= mpiix_init_one,
226 	.remove		= ata_pci_remove_one,
227 #ifdef CONFIG_PM_SLEEP
228 	.suspend	= ata_pci_device_suspend,
229 	.resume		= ata_pci_device_resume,
230 #endif
231 };
232 
233 module_pci_driver(mpiix_pci_driver);
234 
235 MODULE_AUTHOR("Alan Cox");
236 MODULE_DESCRIPTION("low-level driver for Intel MPIIX");
237 MODULE_LICENSE("GPL");
238 MODULE_DEVICE_TABLE(pci, mpiix);
239 MODULE_VERSION(DRV_VERSION);
240