CRISv32: add unreachable() to BUG()
[linux/fpc-iii.git] / drivers / ata / pata_mpiix.c
blob202b4d601393c918cb5154e674fbfad46f59ac83
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>
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.
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).
18 * The driver consciously keeps this logic internally to avoid pushing quirky
19 * PATA history into the clean libata layer.
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.
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>
36 #define DRV_NAME "pata_mpiix"
37 #define DRV_VERSION "0.7.7"
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)
48 static int mpiix_pre_reset(struct ata_link *link, unsigned long deadline)
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 };
54 if (!pci_test_config_bits(pdev, &mpiix_enable_bits))
55 return -ENOENT;
57 return ata_sff_prereset(link, deadline);
60 /**
61 * mpiix_set_piomode - set initial PIO mode data
62 * @ap: ATA interface
63 * @adev: ATA device
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.
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.
75 static void mpiix_set_piomode(struct ata_port *ap, struct ata_device *adev)
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 }, };
88 pci_read_config_word(pdev, IDETIM, &idetim);
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 */
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);
103 idetim |= (timings[pio][0] << 12) | (timings[pio][1] << 8);
104 pci_write_config_word(pdev, IDETIM, idetim);
106 /* We use ap->private_data as a pointer to the device currently
107 loaded for timing */
108 ap->private_data = adev;
112 * mpiix_qc_issue - command issue
113 * @qc: command pending
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.
122 static unsigned int mpiix_qc_issue(struct ata_queued_cmd *qc)
124 struct ata_port *ap = qc->ap;
125 struct ata_device *adev = qc->dev;
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 */
132 if (adev->pio_mode && adev != ap->private_data)
133 mpiix_set_piomode(ap, adev);
135 return ata_sff_qc_issue(qc);
138 static struct scsi_host_template mpiix_sht = {
139 ATA_PIO_SHT(DRV_NAME),
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,
151 static int mpiix_init_one(struct pci_dev *dev, const struct pci_device_id *id)
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;
160 ata_print_version_once(&dev->dev, DRV_VERSION);
162 host = ata_host_alloc(&dev->dev, 1);
163 if (!host)
164 return -ENOMEM;
165 ap = host->ports[0];
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 */
171 pci_read_config_word(dev, IDETIM, &idetim);
172 if (!(idetim & ENABLED))
173 return -ENODEV;
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;
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;
191 ata_port_desc(ap, "cmd 0x%x ctl 0x%x", cmd, ctl);
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 */
199 ap->ops = &mpiix_port_ops;
200 ap->pio_mask = ATA_PIO4;
201 ap->flags |= ATA_FLAG_SLAVE_POSS;
203 ap->ioaddr.cmd_addr = cmd_addr;
204 ap->ioaddr.ctl_addr = ctl_addr;
205 ap->ioaddr.altstatus_addr = ctl_addr;
207 /* Let libata fill in the port details */
208 ata_sff_std_ports(&ap->ioaddr);
210 /* activate host */
211 return ata_host_activate(host, irq, ata_sff_interrupt, IRQF_SHARED,
212 &mpiix_sht);
215 static const struct pci_device_id mpiix[] = {
216 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_82371MX), },
218 { },
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_SLEEP
227 .suspend = ata_pci_device_suspend,
228 .resume = ata_pci_device_resume,
229 #endif
232 module_pci_driver(mpiix_pci_driver);
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);