[libata] Add a bunch of PATA drivers.

The vast majority of drivers and changes are from Alan Cox.  Albert Lee
contributed and maintains pata_pdc2027x.  Adrian Bunk, Andrew Morton,
and Tejun Heo contributed various minor fixes and updates.

Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 869 insertions, 0 deletions

diff --git a/drivers/ata/pata_pdc2027x.c b/drivers/ata/pata_pdc2027x.c
new file mode 100644
index 00000000000..56b8c1ee293
--- /dev/null
+++ b/drivers/ata/pata_pdc2027x.c
@@ -0,0 +1,869 @@
+/*
+ *  Promise PATA TX2/TX4/TX2000/133 IDE driver for pdc20268 to pdc20277.
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ *  Ported to libata by:
+ *  Albert Lee <albertcc@tw.ibm.com> IBM Corporation
+ *
+ *  Copyright (C) 1998-2002		Andre Hedrick <andre@linux-ide.org>
+ *  Portions Copyright (C) 1999 Promise Technology, Inc.
+ *
+ *  Author: Frank Tiernan (frankt@promise.com)
+ *  Released under terms of General Public License
+ *
+ *
+ *  libata documentation is available via 'make {ps|pdf}docs',
+ *  as Documentation/DocBook/libata.*
+ *
+ *  Hardware information only available under NDA.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_cmnd.h>
+#include <linux/libata.h>
+#include <asm/io.h>
+
+#define DRV_NAME	"pata_pdc2027x"
+#define DRV_VERSION	"0.74-ac3"
+#undef PDC_DEBUG
+
+#ifdef PDC_DEBUG
+#define PDPRINTK(fmt, args...) printk(KERN_ERR "%s: " fmt, __FUNCTION__, ## args)
+#else
+#define PDPRINTK(fmt, args...)
+#endif
+
+enum {
+	PDC_UDMA_100		= 0,
+	PDC_UDMA_133		= 1,
+
+	PDC_100_MHZ		= 100000000,
+	PDC_133_MHZ		= 133333333,
+
+	PDC_SYS_CTL		= 0x1100,
+	PDC_ATA_CTL		= 0x1104,
+	PDC_GLOBAL_CTL		= 0x1108,
+	PDC_CTCR0		= 0x110C,
+	PDC_CTCR1		= 0x1110,
+	PDC_BYTE_COUNT		= 0x1120,
+	PDC_PLL_CTL		= 0x1202,
+};
+
+static int pdc2027x_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
+static void pdc2027x_remove_one(struct pci_dev *pdev);
+static void pdc2027x_error_handler(struct ata_port *ap);
+static void pdc2027x_set_piomode(struct ata_port *ap, struct ata_device *adev);
+static void pdc2027x_set_dmamode(struct ata_port *ap, struct ata_device *adev);
+static void pdc2027x_post_set_mode(struct ata_port *ap);
+static int pdc2027x_check_atapi_dma(struct ata_queued_cmd *qc);
+
+/*
+ * ATA Timing Tables based on 133MHz controller clock.
+ * These tables are only used when the controller is in 133MHz clock.
+ * If the controller is in 100MHz clock, the ASIC hardware will
+ * set the timing registers automatically when "set feature" command
+ * is issued to the device. However, if the controller clock is 133MHz,
+ * the following tables must be used.
+ */
+static struct pdc2027x_pio_timing {
+	u8 value0, value1, value2;
+} pdc2027x_pio_timing_tbl [] = {
+	{ 0xfb, 0x2b, 0xac }, /* PIO mode 0 */
+	{ 0x46, 0x29, 0xa4 }, /* PIO mode 1 */
+	{ 0x23, 0x26, 0x64 }, /* PIO mode 2 */
+	{ 0x27, 0x0d, 0x35 }, /* PIO mode 3, IORDY on, Prefetch off */
+	{ 0x23, 0x09, 0x25 }, /* PIO mode 4, IORDY on, Prefetch off */
+};
+
+static struct pdc2027x_mdma_timing {
+	u8 value0, value1;
+} pdc2027x_mdma_timing_tbl [] = {
+	{ 0xdf, 0x5f }, /* MDMA mode 0 */
+	{ 0x6b, 0x27 }, /* MDMA mode 1 */
+	{ 0x69, 0x25 }, /* MDMA mode 2 */
+};
+
+static struct pdc2027x_udma_timing {
+	u8 value0, value1, value2;
+} pdc2027x_udma_timing_tbl [] = {
+	{ 0x4a, 0x0f, 0xd5 }, /* UDMA mode 0 */
+	{ 0x3a, 0x0a, 0xd0 }, /* UDMA mode 1 */
+	{ 0x2a, 0x07, 0xcd }, /* UDMA mode 2 */
+	{ 0x1a, 0x05, 0xcd }, /* UDMA mode 3 */
+	{ 0x1a, 0x03, 0xcd }, /* UDMA mode 4 */
+	{ 0x1a, 0x02, 0xcb }, /* UDMA mode 5 */
+	{ 0x1a, 0x01, 0xcb }, /* UDMA mode 6 */
+};
+
+static const struct pci_device_id pdc2027x_pci_tbl[] = {
+	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20268, PCI_ANY_ID, PCI_ANY_ID, 0, 0, PDC_UDMA_100 },
+	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20269, PCI_ANY_ID, PCI_ANY_ID, 0, 0, PDC_UDMA_133 },
+	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20270, PCI_ANY_ID, PCI_ANY_ID, 0, 0, PDC_UDMA_100 },
+	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20271, PCI_ANY_ID, PCI_ANY_ID, 0, 0, PDC_UDMA_133 },
+	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20275, PCI_ANY_ID, PCI_ANY_ID, 0, 0, PDC_UDMA_133 },
+	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20276, PCI_ANY_ID, PCI_ANY_ID, 0, 0, PDC_UDMA_133 },
+	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20277, PCI_ANY_ID, PCI_ANY_ID, 0, 0, PDC_UDMA_133 },
+	{ }	/* terminate list */
+};
+
+static struct pci_driver pdc2027x_pci_driver = {
+	.name			= DRV_NAME,
+	.id_table		= pdc2027x_pci_tbl,
+	.probe			= pdc2027x_init_one,
+	.remove			= __devexit_p(pdc2027x_remove_one),
+};
+
+static struct scsi_host_template pdc2027x_sht = {
+	.module			= THIS_MODULE,
+	.name			= DRV_NAME,
+	.ioctl			= ata_scsi_ioctl,
+	.queuecommand		= ata_scsi_queuecmd,
+	.can_queue		= ATA_DEF_QUEUE,
+	.this_id		= ATA_SHT_THIS_ID,
+	.sg_tablesize		= LIBATA_MAX_PRD,
+	.max_sectors		= ATA_MAX_SECTORS,
+	.cmd_per_lun		= ATA_SHT_CMD_PER_LUN,
+	.emulated		= ATA_SHT_EMULATED,
+	.use_clustering		= ATA_SHT_USE_CLUSTERING,
+	.proc_name		= DRV_NAME,
+	.dma_boundary		= ATA_DMA_BOUNDARY,
+	.slave_configure	= ata_scsi_slave_config,
+	.bios_param		= ata_std_bios_param,
+};
+
+static struct ata_port_operations pdc2027x_pata100_ops = {
+	.port_disable		= ata_port_disable,
+
+	.tf_load		= ata_tf_load,
+	.tf_read		= ata_tf_read,
+	.check_status		= ata_check_status,
+	.exec_command		= ata_exec_command,
+	.dev_select		= ata_std_dev_select,
+
+	.check_atapi_dma	= pdc2027x_check_atapi_dma,
+	.bmdma_setup		= ata_bmdma_setup,
+	.bmdma_start		= ata_bmdma_start,
+	.bmdma_stop		= ata_bmdma_stop,
+	.bmdma_status		= ata_bmdma_status,
+	.qc_prep		= ata_qc_prep,
+	.qc_issue		= ata_qc_issue_prot,
+	.data_xfer		= ata_mmio_data_xfer,
+
+	.freeze			= ata_bmdma_freeze,
+	.thaw			= ata_bmdma_thaw,
+	.error_handler		= pdc2027x_error_handler,
+	.post_internal_cmd 	= ata_bmdma_post_internal_cmd,
+
+	.irq_handler		= ata_interrupt,
+	.irq_clear		= ata_bmdma_irq_clear,
+
+	.port_start		= ata_port_start,
+	.port_stop		= ata_port_stop,
+	.host_stop		= ata_pci_host_stop,
+};
+
+static struct ata_port_operations pdc2027x_pata133_ops = {
+	.port_disable		= ata_port_disable,
+	.set_piomode		= pdc2027x_set_piomode,
+	.set_dmamode		= pdc2027x_set_dmamode,
+	.post_set_mode		= pdc2027x_post_set_mode,
+
+	.tf_load		= ata_tf_load,
+	.tf_read		= ata_tf_read,
+	.check_status		= ata_check_status,
+	.exec_command		= ata_exec_command,
+	.dev_select		= ata_std_dev_select,
+
+	.check_atapi_dma	= pdc2027x_check_atapi_dma,
+	.bmdma_setup		= ata_bmdma_setup,
+	.bmdma_start		= ata_bmdma_start,
+	.bmdma_stop		= ata_bmdma_stop,
+	.bmdma_status		= ata_bmdma_status,
+	.qc_prep		= ata_qc_prep,
+	.qc_issue		= ata_qc_issue_prot,
+	.data_xfer		= ata_mmio_data_xfer,
+
+	.freeze			= ata_bmdma_freeze,
+	.thaw			= ata_bmdma_thaw,
+	.error_handler		= pdc2027x_error_handler,
+	.post_internal_cmd	= ata_bmdma_post_internal_cmd,
+
+	.irq_handler		= ata_interrupt,
+	.irq_clear		= ata_bmdma_irq_clear,
+
+	.port_start		= ata_port_start,
+	.port_stop		= ata_port_stop,
+	.host_stop		= ata_pci_host_stop,
+};
+
+static struct ata_port_info pdc2027x_port_info[] = {
+	/* PDC_UDMA_100 */
+	{
+		.sht		= &pdc2027x_sht,
+		.flags		= ATA_FLAG_NO_LEGACY | ATA_FLAG_SLAVE_POSS |
+		                  ATA_FLAG_MMIO,
+		.pio_mask	= 0x1f, /* pio0-4 */
+		.mwdma_mask	= 0x07, /* mwdma0-2 */
+		.udma_mask	= ATA_UDMA5, /* udma0-5 */
+		.port_ops	= &pdc2027x_pata100_ops,
+	},
+	/* PDC_UDMA_133 */
+	{
+		.sht		= &pdc2027x_sht,
+		.flags		= ATA_FLAG_NO_LEGACY | ATA_FLAG_SLAVE_POSS |
+                        	  ATA_FLAG_MMIO,
+		.pio_mask	= 0x1f, /* pio0-4 */
+		.mwdma_mask	= 0x07, /* mwdma0-2 */
+		.udma_mask	= ATA_UDMA6, /* udma0-6 */
+		.port_ops	= &pdc2027x_pata133_ops,
+	},
+};
+
+MODULE_AUTHOR("Andre Hedrick, Frank Tiernan, Albert Lee");
+MODULE_DESCRIPTION("libata driver module for Promise PDC20268 to PDC20277");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);
+MODULE_DEVICE_TABLE(pci, pdc2027x_pci_tbl);
+
+/**
+ *	port_mmio - Get the MMIO address of PDC2027x extended registers
+ *	@ap: Port
+ *	@offset: offset from mmio base
+ */
+static inline void* port_mmio(struct ata_port *ap, unsigned int offset)
+{
+	return ap->host->mmio_base + ap->port_no * 0x100 + offset;
+}
+
+/**
+ *	dev_mmio - Get the MMIO address of PDC2027x extended registers
+ *	@ap: Port
+ *	@adev: device
+ *	@offset: offset from mmio base
+ */
+static inline void* dev_mmio(struct ata_port *ap, struct ata_device *adev, unsigned int offset)
+{
+	u8 adj = (adev->devno) ? 0x08 : 0x00;
+	return port_mmio(ap, offset) + adj;
+}
+
+/**
+ *	pdc2027x_pata_cbl_detect - Probe host controller cable detect info
+ *	@ap: Port for which cable detect info is desired
+ *
+ *	Read 80c cable indicator from Promise extended register.
+ *      This register is latched when the system is reset.
+ *
+ *	LOCKING:
+ *	None (inherited from caller).
+ */
+static void pdc2027x_cbl_detect(struct ata_port *ap)
+{
+	u32 cgcr;
+
+	/* check cable detect results */
+	cgcr = readl(port_mmio(ap, PDC_GLOBAL_CTL));
+	if (cgcr & (1 << 26))
+		goto cbl40;
+
+	PDPRINTK("No cable or 80-conductor cable on port %d\n", ap->port_no);
+
+	ap->cbl = ATA_CBL_PATA80;
+	return;
+
+cbl40:
+	printk(KERN_INFO DRV_NAME ": 40-conductor cable detected on port %d\n", ap->port_no);
+	ap->cbl = ATA_CBL_PATA40;
+	ap->udma_mask &= ATA_UDMA_MASK_40C;
+}
+
+/**
+ * pdc2027x_port_enabled - Check PDC ATA control register to see whether the port is enabled.
+ * @ap: Port to check
+ */
+static inline int pdc2027x_port_enabled(struct ata_port *ap)
+{
+	return readb(port_mmio(ap, PDC_ATA_CTL)) & 0x02;
+}
+
+/**
+ *	pdc2027x_prereset - prereset for PATA host controller
+ *	@ap: Target port
+ *
+ *	Probeinit including cable detection.
+ *
+ *	LOCKING:
+ *	None (inherited from caller).
+ */
+
+static int pdc2027x_prereset(struct ata_port *ap)
+{
+	/* Check whether port enabled */
+	if (!pdc2027x_port_enabled(ap)) {
+		printk(KERN_INFO "ata%u: port disabled. ignoring.\n", ap->id);
+		return 0;
+	}
+	pdc2027x_cbl_detect(ap);
+	return ata_std_prereset(ap);
+}
+
+/**
+ *	pdc2027x_error_handler - Perform reset on PATA port and classify
+ *	@ap: Port to reset
+ *
+ *	Reset PATA phy and classify attached devices.
+ *
+ *	LOCKING:
+ *	None (inherited from caller).
+ */
+
+static void pdc2027x_error_handler(struct ata_port *ap)
+{
+	ata_bmdma_drive_eh(ap, pdc2027x_prereset, ata_std_softreset, NULL, ata_std_postreset);
+}
+
+/**
+ *	pdc2027x_set_piomode - Initialize host controller PATA PIO timings
+ *	@ap: Port to configure
+ *	@adev: um
+ *	@pio: PIO mode, 0 - 4
+ *
+ *	Set PIO mode for device.
+ *
+ *	LOCKING:
+ *	None (inherited from caller).
+ */
+
+static void pdc2027x_set_piomode(struct ata_port *ap, struct ata_device *adev)
+{
+	unsigned int pio = adev->pio_mode - XFER_PIO_0;
+	u32 ctcr0, ctcr1;
+
+	PDPRINTK("adev->pio_mode[%X]\n", adev->pio_mode);
+
+	/* Sanity check */
+	if (pio > 4) {
+		printk(KERN_ERR DRV_NAME ": Unknown pio mode [%d] ignored\n", pio);
+		return;
+
+	}
+
+	/* Set the PIO timing registers using value table for 133MHz */
+	PDPRINTK("Set pio regs... \n");
+
+	ctcr0 = readl(dev_mmio(ap, adev, PDC_CTCR0));
+	ctcr0 &= 0xffff0000;
+	ctcr0 |= pdc2027x_pio_timing_tbl[pio].value0 |
+		(pdc2027x_pio_timing_tbl[pio].value1 << 8);
+	writel(ctcr0, dev_mmio(ap, adev, PDC_CTCR0));
+
+	ctcr1 = readl(dev_mmio(ap, adev, PDC_CTCR1));
+	ctcr1 &= 0x00ffffff;
+	ctcr1 |= (pdc2027x_pio_timing_tbl[pio].value2 << 24);
+	writel(ctcr1, dev_mmio(ap, adev, PDC_CTCR1));
+
+	PDPRINTK("Set pio regs done\n");
+
+	PDPRINTK("Set to pio mode[%u] \n", pio);
+}
+
+/**
+ *	pdc2027x_set_dmamode - Initialize host controller PATA UDMA timings
+ *	@ap: Port to configure
+ *	@adev: um
+ *	@udma: udma mode, XFER_UDMA_0 to XFER_UDMA_6
+ *
+ *	Set UDMA mode for device.
+ *
+ *	LOCKING:
+ *	None (inherited from caller).
+ */
+static void pdc2027x_set_dmamode(struct ata_port *ap, struct ata_device *adev)
+{
+	unsigned int dma_mode = adev->dma_mode;
+	u32 ctcr0, ctcr1;
+
+	if ((dma_mode >= XFER_UDMA_0) &&
+	   (dma_mode <= XFER_UDMA_6)) {
+		/* Set the UDMA timing registers with value table for 133MHz */
+		unsigned int udma_mode = dma_mode & 0x07;
+
+		if (dma_mode == XFER_UDMA_2) {
+			/*
+			 * Turn off tHOLD.
+			 * If tHOLD is '1', the hardware will add half clock for data hold time.
+			 * This code segment seems to be no effect. tHOLD will be overwritten below.
+			 */
+			ctcr1 = readl(dev_mmio(ap, adev, PDC_CTCR1));
+			writel(ctcr1 & ~(1 << 7), dev_mmio(ap, adev, PDC_CTCR1));
+		}
+
+		PDPRINTK("Set udma regs... \n");
+
+		ctcr1 = readl(dev_mmio(ap, adev, PDC_CTCR1));
+		ctcr1 &= 0xff000000;
+		ctcr1 |= pdc2027x_udma_timing_tbl[udma_mode].value0 |
+			(pdc2027x_udma_timing_tbl[udma_mode].value1 << 8) |
+			(pdc2027x_udma_timing_tbl[udma_mode].value2 << 16);
+		writel(ctcr1, dev_mmio(ap, adev, PDC_CTCR1));
+
+		PDPRINTK("Set udma regs done\n");
+
+		PDPRINTK("Set to udma mode[%u] \n", udma_mode);
+
+	} else  if ((dma_mode >= XFER_MW_DMA_0) &&
+		   (dma_mode <= XFER_MW_DMA_2)) {
+		/* Set the MDMA timing registers with value table for 133MHz */
+		unsigned int mdma_mode = dma_mode & 0x07;
+
+		PDPRINTK("Set mdma regs... \n");
+		ctcr0 = readl(dev_mmio(ap, adev, PDC_CTCR0));
+
+		ctcr0 &= 0x0000ffff;
+		ctcr0 |= (pdc2027x_mdma_timing_tbl[mdma_mode].value0 << 16) |
+			(pdc2027x_mdma_timing_tbl[mdma_mode].value1 << 24);
+
+		writel(ctcr0, dev_mmio(ap, adev, PDC_CTCR0));
+		PDPRINTK("Set mdma regs done\n");
+
+		PDPRINTK("Set to mdma mode[%u] \n", mdma_mode);
+	} else {
+		printk(KERN_ERR DRV_NAME ": Unknown dma mode [%u] ignored\n", dma_mode);
+	}
+}
+
+/**
+ *	pdc2027x_post_set_mode - Set the timing registers back to correct values.
+ *	@ap: Port to configure
+ *
+ *	The pdc2027x hardware will look at "SET FEATURES" and change the timing registers
+ *	automatically. The values set by the hardware might be incorrect, under 133Mhz PLL.
+ *	This function overwrites the possibly incorrect values set by the hardware to be correct.
+ */
+static void pdc2027x_post_set_mode(struct ata_port *ap)
+{
+	int i;
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		struct ata_device *dev = &ap->device[i];
+
+		if (ata_dev_enabled(dev)) {
+
+			pdc2027x_set_piomode(ap, dev);
+
+			/*
+			 * Enable prefetch if the device support PIO only.
+			 */
+			if (dev->xfer_shift == ATA_SHIFT_PIO) {
+				u32 ctcr1 = readl(dev_mmio(ap, dev, PDC_CTCR1));
+				ctcr1 |= (1 << 25);
+				writel(ctcr1, dev_mmio(ap, dev, PDC_CTCR1));
+
+				PDPRINTK("Turn on prefetch\n");
+			} else {
+				pdc2027x_set_dmamode(ap, dev);
+			}
+		}
+	}
+}
+
+/**
+ *	pdc2027x_check_atapi_dma - Check whether ATAPI DMA can be supported for this command
+ *	@qc: Metadata associated with taskfile to check
+ *
+ *	LOCKING:
+ *	None (inherited from caller).
+ *
+ *	RETURNS: 0 when ATAPI DMA can be used
+ *		 1 otherwise
+ */
+static int pdc2027x_check_atapi_dma(struct ata_queued_cmd *qc)
+{
+	struct scsi_cmnd *cmd = qc->scsicmd;
+	u8 *scsicmd = cmd->cmnd;
+	int rc = 1; /* atapi dma off by default */
+
+	/*
+	 * This workaround is from Promise's GPL driver.
+	 * If ATAPI DMA is used for commands not in the
+	 * following white list, say MODE_SENSE and REQUEST_SENSE,
+	 * pdc2027x might hit the irq lost problem.
+	 */
+	switch (scsicmd[0]) {
+	case READ_10:
+	case WRITE_10:
+	case READ_12:
+	case WRITE_12:
+	case READ_6:
+	case WRITE_6:
+	case 0xad: /* READ_DVD_STRUCTURE */
+	case 0xbe: /* READ_CD */
+		/* ATAPI DMA is ok */
+		rc = 0;
+		break;
+	default:
+		;
+	}
+
+	return rc;
+}
+
+/**
+ * pdc_read_counter - Read the ctr counter
+ * @probe_ent: for the port address
+ */
+
+static long pdc_read_counter(struct ata_probe_ent *probe_ent)
+{
+	long counter;
+	int retry = 1;
+	u32 bccrl, bccrh, bccrlv, bccrhv;
+
+retry:
+	bccrl = readl(probe_ent->mmio_base + PDC_BYTE_COUNT) & 0xffff;
+	bccrh = readl(probe_ent->mmio_base + PDC_BYTE_COUNT + 0x100) & 0xffff;
+	rmb();
+
+	/* Read the counter values again for verification */
+	bccrlv = readl(probe_ent->mmio_base + PDC_BYTE_COUNT) & 0xffff;
+	bccrhv = readl(probe_ent->mmio_base + PDC_BYTE_COUNT + 0x100) & 0xffff;
+	rmb();
+
+	counter = (bccrh << 15) | bccrl;
+
+	PDPRINTK("bccrh [%X] bccrl [%X]\n", bccrh,  bccrl);
+	PDPRINTK("bccrhv[%X] bccrlv[%X]\n", bccrhv, bccrlv);
+
+	/*
+	 * The 30-bit decreasing counter are read by 2 pieces.
+	 * Incorrect value may be read when both bccrh and bccrl are changing.
+	 * Ex. When 7900 decrease to 78FF, wrong value 7800 might be read.
+	 */
+	if (retry && !(bccrh == bccrhv && bccrl >= bccrlv)) {
+		retry--;
+		PDPRINTK("rereading counter\n");
+		goto retry;
+	}
+
+	return counter;
+}
+
+/**
+ * adjust_pll - Adjust the PLL input clock in Hz.
+ *
+ * @pdc_controller: controller specific information
+ * @probe_ent: For the port address
+ * @pll_clock: The input of PLL in HZ
+ */
+static void pdc_adjust_pll(struct ata_probe_ent *probe_ent, long pll_clock, unsigned int board_idx)
+{
+
+	u16 pll_ctl;
+	long pll_clock_khz = pll_clock / 1000;
+	long pout_required = board_idx? PDC_133_MHZ:PDC_100_MHZ;
+	long ratio = pout_required / pll_clock_khz;
+	int F, R;
+
+	/* Sanity check */
+	if (unlikely(pll_clock_khz < 5000L || pll_clock_khz > 70000L)) {
+		printk(KERN_ERR DRV_NAME ": Invalid PLL input clock %ldkHz, give up!\n", pll_clock_khz);
+		return;
+	}
+
+#ifdef PDC_DEBUG
+	PDPRINTK("pout_required is %ld\n", pout_required);
+
+	/* Show the current clock value of PLL control register
+	 * (maybe already configured by the firmware)
+	 */
+	pll_ctl = readw(probe_ent->mmio_base + PDC_PLL_CTL);
+
+	PDPRINTK("pll_ctl[%X]\n", pll_ctl);
+#endif
+
+	/*
+	 * Calculate the ratio of F, R and OD
+	 * POUT = (F + 2) / (( R + 2) * NO)
+	 */
+	if (ratio < 8600L) { /* 8.6x */
+		/* Using NO = 0x01, R = 0x0D */
+		R = 0x0d;
+	} else if (ratio < 12900L) { /* 12.9x */
+		/* Using NO = 0x01, R = 0x08 */
+		R = 0x08;
+	} else if (ratio < 16100L) { /* 16.1x */
+		/* Using NO = 0x01, R = 0x06 */
+		R = 0x06;
+	} else if (ratio < 64000L) { /* 64x */
+		R = 0x00;
+	} else {
+		/* Invalid ratio */
+		printk(KERN_ERR DRV_NAME ": Invalid ratio %ld, give up!\n", ratio);
+		return;
+	}
+
+	F = (ratio * (R+2)) / 1000 - 2;
+
+	if (unlikely(F < 0 || F > 127)) {
+		/* Invalid F */
+		printk(KERN_ERR DRV_NAME ": F[%d] invalid!\n", F);
+		return;
+	}
+
+	PDPRINTK("F[%d] R[%d] ratio*1000[%ld]\n", F, R, ratio);
+
+	pll_ctl = (R << 8) | F;
+
+	PDPRINTK("Writing pll_ctl[%X]\n", pll_ctl);
+
+	writew(pll_ctl, probe_ent->mmio_base + PDC_PLL_CTL);
+	readw(probe_ent->mmio_base + PDC_PLL_CTL); /* flush */
+
+	/* Wait the PLL circuit to be stable */
+	mdelay(30);
+
+#ifdef PDC_DEBUG
+	/*
+	 *  Show the current clock value of PLL control register
+	 * (maybe configured by the firmware)
+	 */
+	pll_ctl = readw(probe_ent->mmio_base + PDC_PLL_CTL);
+
+	PDPRINTK("pll_ctl[%X]\n", pll_ctl);
+#endif
+
+	return;
+}
+
+/**
+ * detect_pll_input_clock - Detect the PLL input clock in Hz.
+ * @probe_ent: for the port address
+ * Ex. 16949000 on 33MHz PCI bus for pdc20275.
+ *     Half of the PCI clock.
+ */
+static long pdc_detect_pll_input_clock(struct ata_probe_ent *probe_ent)
+{
+	u32 scr;
+	long start_count, end_count;
+	long pll_clock;
+
+	/* Read current counter value */
+	start_count = pdc_read_counter(probe_ent);
+
+	/* Start the test mode */
+	scr = readl(probe_ent->mmio_base + PDC_SYS_CTL);
+	PDPRINTK("scr[%X]\n", scr);
+	writel(scr | (0x01 << 14), probe_ent->mmio_base + PDC_SYS_CTL);
+	readl(probe_ent->mmio_base + PDC_SYS_CTL); /* flush */
+
+	/* Let the counter run for 100 ms. */
+	mdelay(100);
+
+	/* Read the counter values again */
+	end_count = pdc_read_counter(probe_ent);
+
+	/* Stop the test mode */
+	scr = readl(probe_ent->mmio_base + PDC_SYS_CTL);
+	PDPRINTK("scr[%X]\n", scr);
+	writel(scr & ~(0x01 << 14), probe_ent->mmio_base + PDC_SYS_CTL);
+	readl(probe_ent->mmio_base + PDC_SYS_CTL); /* flush */
+
+	/* calculate the input clock in Hz */
+	pll_clock = (start_count - end_count) * 10;
+
+	PDPRINTK("start[%ld] end[%ld] \n", start_count, end_count);
+	PDPRINTK("PLL input clock[%ld]Hz\n", pll_clock);
+
+	return pll_clock;
+}
+
+/**
+ * pdc_hardware_init - Initialize the hardware.
+ * @pdev: instance of pci_dev found
+ * @pdc_controller: controller specific information
+ * @pe:  for the port address
+ */
+static int pdc_hardware_init(struct pci_dev *pdev, struct ata_probe_ent *pe, unsigned int board_idx)
+{
+	long pll_clock;
+
+	/*
+	 * Detect PLL input clock rate.
+	 * On some system, where PCI bus is running at non-standard clock rate.
+	 * Ex. 25MHz or 40MHz, we have to adjust the cycle_time.
+	 * The pdc20275 controller employs PLL circuit to help correct timing registers setting.
+	 */
+	pll_clock = pdc_detect_pll_input_clock(pe);
+
+	if (pll_clock < 0) /* counter overflow? Try again. */
+		pll_clock = pdc_detect_pll_input_clock(pe);
+
+	dev_printk(KERN_INFO, &pdev->dev, "PLL input clock %ld kHz\n", pll_clock/1000);
+
+	/* Adjust PLL control register */
+	pdc_adjust_pll(pe, pll_clock, board_idx);
+
+	return 0;
+}
+
+/**
+ * pdc_ata_setup_port - setup the mmio address
+ * @port: ata ioports to setup
+ * @base: base address
+ */
+static void pdc_ata_setup_port(struct ata_ioports *port, unsigned long base)
+{
+	port->cmd_addr		=
+	port->data_addr		= base;
+	port->feature_addr	=
+	port->error_addr	= base + 0x05;
+	port->nsect_addr	= base + 0x0a;
+	port->lbal_addr		= base + 0x0f;
+	port->lbam_addr		= base + 0x10;
+	port->lbah_addr		= base + 0x15;
+	port->device_addr	= base + 0x1a;
+	port->command_addr	=
+	port->status_addr	= base + 0x1f;
+	port->altstatus_addr	=
+	port->ctl_addr		= base + 0x81a;
+}
+
+/**
+ * pdc2027x_init_one - PCI probe function
+ * Called when an instance of PCI adapter is inserted.
+ * This function checks whether the hardware is supported,
+ * initialize hardware and register an instance of ata_host to
+ * libata by providing struct ata_probe_ent and ata_device_add().
+ * (implements struct pci_driver.probe() )
+ *
+ * @pdev: instance of pci_dev found
+ * @ent:  matching entry in the id_tbl[]
+ */
+static int __devinit pdc2027x_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	static int printed_version;
+	unsigned int board_idx = (unsigned int) ent->driver_data;
+
+	struct ata_probe_ent *probe_ent = NULL;
+	unsigned long base;
+	void *mmio_base;
+	int rc;
+
+	if (!printed_version++)
+		dev_printk(KERN_DEBUG, &pdev->dev, "version " DRV_VERSION "\n");
+
+	rc = pci_enable_device(pdev);
+	if (rc)
+		return rc;
+
+	rc = pci_request_regions(pdev, DRV_NAME);
+	if (rc)
+		goto err_out;
+
+	rc = pci_set_dma_mask(pdev, ATA_DMA_MASK);
+	if (rc)
+		goto err_out_regions;
+
+	rc = pci_set_consistent_dma_mask(pdev, ATA_DMA_MASK);
+	if (rc)
+		goto err_out_regions;
+
+	/* Prepare the probe entry */
+	probe_ent = kzalloc(sizeof(*probe_ent), GFP_KERNEL);
+	if (probe_ent == NULL) {
+		rc = -ENOMEM;
+		goto err_out_regions;
+	}
+
+	probe_ent->dev = pci_dev_to_dev(pdev);
+	INIT_LIST_HEAD(&probe_ent->node);
+
+	mmio_base = pci_iomap(pdev, 5, 0);
+	if (!mmio_base) {
+		rc = -ENOMEM;
+		goto err_out_free_ent;
+	}
+
+	base = (unsigned long) mmio_base;
+
+	probe_ent->sht		= pdc2027x_port_info[board_idx].sht;
+	probe_ent->port_flags	= pdc2027x_port_info[board_idx].flags;
+	probe_ent->pio_mask	= pdc2027x_port_info[board_idx].pio_mask;
+	probe_ent->mwdma_mask	= pdc2027x_port_info[board_idx].mwdma_mask;
+	probe_ent->udma_mask	= pdc2027x_port_info[board_idx].udma_mask;
+	probe_ent->port_ops	= pdc2027x_port_info[board_idx].port_ops;
+
+       	probe_ent->irq = pdev->irq;
+       	probe_ent->irq_flags = SA_SHIRQ;
+	probe_ent->mmio_base = mmio_base;
+
+	pdc_ata_setup_port(&probe_ent->port[0], base + 0x17c0);
+	probe_ent->port[0].bmdma_addr = base + 0x1000;
+	pdc_ata_setup_port(&probe_ent->port[1], base + 0x15c0);
+	probe_ent->port[1].bmdma_addr = base + 0x1008;
+
+	probe_ent->n_ports = 2;
+
+	pci_set_master(pdev);
+	//pci_enable_intx(pdev);
+
+	/* initialize adapter */
+	if (pdc_hardware_init(pdev, probe_ent, board_idx) != 0)
+		goto err_out_free_ent;
+
+	ata_device_add(probe_ent);
+	kfree(probe_ent);
+
+	return 0;
+
+err_out_free_ent:
+	kfree(probe_ent);
+err_out_regions:
+	pci_release_regions(pdev);
+err_out:
+	pci_disable_device(pdev);
+	return rc;
+}
+
+/**
+ * pdc2027x_remove_one - Called to remove a single instance of the
+ * adapter.
+ *
+ * @dev: The PCI device to remove.
+ * FIXME: module load/unload not working yet
+ */
+static void __devexit pdc2027x_remove_one(struct pci_dev *pdev)
+{
+	ata_pci_remove_one(pdev);
+}
+
+/**
+ * pdc2027x_init - Called after this module is loaded into the kernel.
+ */
+static int __init pdc2027x_init(void)
+{
+	return pci_module_init(&pdc2027x_pci_driver);
+}
+
+/**
+ * pdc2027x_exit - Called before this module unloaded from the kernel
+ */
+static void __exit pdc2027x_exit(void)
+{
+	pci_unregister_driver(&pdc2027x_pci_driver);
+}
+
+module_init(pdc2027x_init);
+module_exit(pdc2027x_exit);