/*

   * pata_serverworks.c 	- Serverworks PATA for new ATA layer

   *			  (C) 2005 Red Hat Inc

   *			  (C) 2010 Bartlomiej Zolnierkiewicz

   *
   * based upon
   *
   * serverworks.c

   *

   * Copyright (C) 1998-2000 Michel Aubry
   * Copyright (C) 1998-2000 Andrzej Krzysztofowicz
   * Copyright (C) 1998-2000 Andre Hedrick <andre@linux-ide.org>
   * Portions copyright (c) 2001 Sun Microsystems
   *
   *
   * RCC/ServerWorks IDE driver for Linux
   *
   *   OSB4: `Open South Bridge' IDE Interface (fn 1)
   *         supports UDMA mode 2 (33 MB/s)
   *
   *   CSB5: `Champion South Bridge' IDE Interface (fn 1)
   *         all revisions support UDMA mode 4 (66 MB/s)
   *         revision A2.0 and up support UDMA mode 5 (100 MB/s)
   *
   *         *** The CSB5 does not provide ANY register ***
   *         *** to detect 80-conductor cable presence. ***
   *
   *   CSB6: `Champion South Bridge' IDE Interface (optional: third channel)
   *
   * Documentation:
   *	Available under NDA only. Errata info very hard to get.
   */
  
  #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 <scsi/scsi_host.h>
  #include <linux/libata.h>
  
  #define DRV_NAME "pata_serverworks"

  #define DRV_VERSION "0.4.3"

  
  #define SVWKS_CSB5_REVISION_NEW	0x92 /* min PCI_REVISION_ID for UDMA5 (A2.0) */
  #define SVWKS_CSB6_REVISION	0xa0 /* min PCI_REVISION_ID for UDMA4 (A1.0) */
  
  /* Seagate Barracuda ATA IV Family drives in UDMA mode 5
   * can overrun their FIFOs when used with the CSB5 */
  
  static const char *csb_bad_ata100[] = {
  	"ST320011A",
  	"ST340016A",
  	"ST360021A",
  	"ST380021A",
  	NULL
  };
  
  /**

   *	oem_cable	-	Dell/Sun serverworks cable detection

   *	@ap: ATA port to do cable detect
   *

   *	Dell PowerEdge and Sun Cobalt 'Alpine' hide the 40/80 pin select
   *	for their interfaces in the top two bits of the subsystem ID.

   */

  static int oem_cable(struct ata_port *ap)

  {

  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);

  	if (pdev->subsystem_device & (1 << (ap->port_no + 14)))
  		return ATA_CBL_PATA80;
  	return ATA_CBL_PATA40;
  }

  struct sv_cable_table {
  	int device;
  	int subvendor;
  	int (*cable_detect)(struct ata_port *ap);
  };

  static struct sv_cable_table cable_detect[] = {

  	{ PCI_DEVICE_ID_SERVERWORKS_CSB5IDE,   PCI_VENDOR_ID_DELL, oem_cable },
  	{ PCI_DEVICE_ID_SERVERWORKS_CSB6IDE,   PCI_VENDOR_ID_DELL, oem_cable },
  	{ PCI_DEVICE_ID_SERVERWORKS_CSB5IDE,   PCI_VENDOR_ID_SUN,  oem_cable },

  	{ PCI_DEVICE_ID_SERVERWORKS_OSB4IDE,   PCI_ANY_ID, ata_cable_40wire  },
  	{ PCI_DEVICE_ID_SERVERWORKS_CSB5IDE,   PCI_ANY_ID, ata_cable_unknown },
  	{ PCI_DEVICE_ID_SERVERWORKS_CSB6IDE,   PCI_ANY_ID, ata_cable_unknown },
  	{ PCI_DEVICE_ID_SERVERWORKS_CSB6IDE2,  PCI_ANY_ID, ata_cable_unknown },
  	{ PCI_DEVICE_ID_SERVERWORKS_HT1000IDE, PCI_ANY_ID, ata_cable_unknown },

  	{ }
  };
  
  /**

   *	serverworks_cable_detect	-	cable detection

   *	@ap: ATA port
   *

   *	Perform cable detection according to the device and subvendor

   *	identifications
   */

  static int serverworks_cable_detect(struct ata_port *ap)
  {

  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  	struct sv_cable_table *cb = cable_detect;
  
  	while(cb->device) {

  		if (cb->device == pdev->device &&

  		    (cb->subvendor == pdev->subsystem_vendor ||
  		      cb->subvendor == PCI_ANY_ID)) {

  			return cb->cable_detect(ap);

  		}
  		cb++;
  	}
  
  	BUG();
  	return -1;	/* kill compiler warning */
  }

  /**
   *	serverworks_is_csb	-	Check for CSB or OSB
   *	@pdev: PCI device to check
   *
   *	Returns true if the device being checked is known to be a CSB
   *	series device.
   */

  static u8 serverworks_is_csb(struct pci_dev *pdev)
  {
  	switch (pdev->device) {
  		case PCI_DEVICE_ID_SERVERWORKS_CSB5IDE:
  		case PCI_DEVICE_ID_SERVERWORKS_CSB6IDE:
  		case PCI_DEVICE_ID_SERVERWORKS_CSB6IDE2:
  		case PCI_DEVICE_ID_SERVERWORKS_HT1000IDE:
  			return 1;
  		default:
  			break;
  	}
  	return 0;
  }
  
  /**
   *	serverworks_osb4_filter	-	mode selection filter

   *	@adev: ATA device

   *	@mask: Mask of proposed modes

   *
   *	Filter the offered modes for the device to apply controller
   *	specific rules. OSB4 requires no UDMA for disks due to a FIFO
   *	bug we hit.
   */

  static unsigned long serverworks_osb4_filter(struct ata_device *adev, unsigned long mask)

  {
  	if (adev->class == ATA_DEV_ATA)
  		mask &= ~ATA_MASK_UDMA;

  	return mask;

  }
  
  
  /**
   *	serverworks_csb_filter	-	mode selection filter

   *	@adev: ATA device

   *	@mask: Mask of proposed modes

   *
   *	Check the blacklist and disable UDMA5 if matched
   */

  static unsigned long serverworks_csb_filter(struct ata_device *adev, unsigned long mask)

  {
  	const char *p;

  	char model_num[ATA_ID_PROD_LEN + 1];
  	int i;

  	/* Disk, UDMA */

  	if (adev->class != ATA_DEV_ATA)

  		return mask;

  
  	/* Actually do need to check */

  	ata_id_c_string(adev->id, model_num, ATA_ID_PROD, sizeof(model_num));

  	for (i = 0; (p = csb_bad_ata100[i]) != NULL; i++) {
  		if (!strcmp(p, model_num))

  			mask &= ~(0xE0 << ATA_SHIFT_UDMA);

  	}

  	return mask;

  }

  /**
   *	serverworks_set_piomode	-	set initial PIO mode data
   *	@ap: ATA interface
   *	@adev: ATA device
   *
   *	Program the OSB4/CSB5 timing registers for PIO. The PIO register
   *	load is done as a simple lookup.
   */
  static void serverworks_set_piomode(struct ata_port *ap, struct ata_device *adev)
  {
  	static const u8 pio_mode[] = { 0x5d, 0x47, 0x34, 0x22, 0x20 };

  	int offset = 1 + 2 * ap->port_no - adev->devno;

  	int devbits = (2 * ap->port_no + adev->devno) * 4;
  	u16 csb5_pio;
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  	int pio = adev->pio_mode - XFER_PIO_0;
  
  	pci_write_config_byte(pdev, 0x40 + offset, pio_mode[pio]);

  	/* The OSB4 just requires the timing but the CSB series want the
  	   mode number as well */
  	if (serverworks_is_csb(pdev)) {
  		pci_read_config_word(pdev, 0x4A, &csb5_pio);
  		csb5_pio &= ~(0x0F << devbits);

  		pci_write_config_word(pdev, 0x4A, csb5_pio | (pio << devbits));

  	}
  }
  
  /**
   *	serverworks_set_dmamode	-	set initial DMA mode data
   *	@ap: ATA interface
   *	@adev: ATA device
   *
   *	Program the MWDMA/UDMA modes for the serverworks OSB4/CSB5
   *	chipset. The MWDMA mode values are pulled from a lookup table
   *	while the chipset uses mode number for UDMA.
   */
  
  static void serverworks_set_dmamode(struct ata_port *ap, struct ata_device *adev)
  {
  	static const u8 dma_mode[] = { 0x77, 0x21, 0x20 };
  	int offset = 1 + 2 * ap->port_no - adev->devno;

  	int devbits = 2 * ap->port_no + adev->devno;

  	u8 ultra;
  	u8 ultra_cfg;
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  
  	pci_read_config_byte(pdev, 0x54, &ultra_cfg);

  	pci_read_config_byte(pdev, 0x56 + ap->port_no, &ultra);
  	ultra &= ~(0x0F << (adev->devno * 4));

  
  	if (adev->dma_mode >= XFER_UDMA_0) {
  		pci_write_config_byte(pdev, 0x44 + offset,  0x20);

  		ultra |= (adev->dma_mode - XFER_UDMA_0)

  					<< (adev->devno * 4);

  		ultra_cfg |=  (1 << devbits);
  	} else {

  		pci_write_config_byte(pdev, 0x44 + offset,

  			dma_mode[adev->dma_mode - XFER_MW_DMA_0]);
  		ultra_cfg &= ~(1 << devbits);
  	}

  	pci_write_config_byte(pdev, 0x56 + ap->port_no, ultra);

  	pci_write_config_byte(pdev, 0x54, ultra_cfg);
  }
  
  static struct scsi_host_template serverworks_sht = {

  	ATA_BMDMA_SHT(DRV_NAME),

  };
  
  static struct ata_port_operations serverworks_osb4_port_ops = {

  	.inherits	= &ata_bmdma_port_ops,
  	.cable_detect	= serverworks_cable_detect,
  	.mode_filter	= serverworks_osb4_filter,

  	.set_piomode	= serverworks_set_piomode,
  	.set_dmamode	= serverworks_set_dmamode,

  };

  
  static struct ata_port_operations serverworks_csb_port_ops = {

  	.inherits	= &serverworks_osb4_port_ops,

  	.mode_filter	= serverworks_csb_filter,

  };

  
  static int serverworks_fixup_osb4(struct pci_dev *pdev)
  {
  	u32 reg;
  	struct pci_dev *isa_dev = pci_get_device(PCI_VENDOR_ID_SERVERWORKS,
  		  PCI_DEVICE_ID_SERVERWORKS_OSB4, NULL);
  	if (isa_dev) {
  		pci_read_config_dword(isa_dev, 0x64, &reg);
  		reg &= ~0x00002000; /* disable 600ns interrupt mask */
  		if (!(reg & 0x00004000))
  			printk(KERN_DEBUG DRV_NAME ": UDMA not BIOS enabled.
  ");
  		reg |=  0x00004000; /* enable UDMA/33 support */
  		pci_write_config_dword(isa_dev, 0x64, reg);
  		pci_dev_put(isa_dev);
  		return 0;
  	}

  	printk(KERN_WARNING DRV_NAME ": Unable to find bridge.
  ");

  	return -ENODEV;
  }
  
  static int serverworks_fixup_csb(struct pci_dev *pdev)
  {

  	u8 btr;

  	/* Third Channel Test */
  	if (!(PCI_FUNC(pdev->devfn) & 1)) {
  		struct pci_dev * findev = NULL;
  		u32 reg4c = 0;
  		findev = pci_get_device(PCI_VENDOR_ID_SERVERWORKS,
  			PCI_DEVICE_ID_SERVERWORKS_CSB5, NULL);
  		if (findev) {
  			pci_read_config_dword(findev, 0x4C, &reg4c);
  			reg4c &= ~0x000007FF;
  			reg4c |=  0x00000040;
  			reg4c |=  0x00000020;
  			pci_write_config_dword(findev, 0x4C, reg4c);
  			pci_dev_put(findev);
  		}
  	} else {
  		struct pci_dev * findev = NULL;
  		u8 reg41 = 0;
  
  		findev = pci_get_device(PCI_VENDOR_ID_SERVERWORKS,
  				PCI_DEVICE_ID_SERVERWORKS_CSB6, NULL);
  		if (findev) {
  			pci_read_config_byte(findev, 0x41, &reg41);
  			reg41 &= ~0x40;
  			pci_write_config_byte(findev, 0x41, reg41);
  			pci_dev_put(findev);
  		}
  	}
  	/* setup the UDMA Control register
  	 *
  	 * 1. clear bit 6 to enable DMA
  	 * 2. enable DMA modes with bits 0-1
  	 * 	00 : legacy
  	 * 	01 : udma2
  	 * 	10 : udma2/udma4
  	 * 	11 : udma2/udma4/udma5
  	 */
  	pci_read_config_byte(pdev, 0x5A, &btr);
  	btr &= ~0x40;
  	if (!(PCI_FUNC(pdev->devfn) & 1))
  		btr |= 0x2;
  	else

  		btr |= (pdev->revision >= SVWKS_CSB5_REVISION_NEW) ? 0x3 : 0x2;

  	pci_write_config_byte(pdev, 0x5A, btr);

  	return btr;
  }
  
  static void serverworks_fixup_ht1000(struct pci_dev *pdev)
  {
  	u8 btr;
  	/* Setup HT1000 SouthBridge Controller - Single Channel Only */
  	pci_read_config_byte(pdev, 0x5A, &btr);
  	btr &= ~0x40;
  	btr |= 0x3;
  	pci_write_config_byte(pdev, 0x5A, btr);
  }

  static int serverworks_fixup(struct pci_dev *pdev)
  {
  	int rc = 0;
  
  	/* Force master latency timer to 64 PCI clocks */
  	pci_write_config_byte(pdev, PCI_LATENCY_TIMER, 0x40);
  
  	switch (pdev->device) {
  	case PCI_DEVICE_ID_SERVERWORKS_OSB4IDE:
  		rc = serverworks_fixup_osb4(pdev);
  		break;
  	case PCI_DEVICE_ID_SERVERWORKS_CSB5IDE:
  		ata_pci_bmdma_clear_simplex(pdev);
  		/* fall through */
  	case PCI_DEVICE_ID_SERVERWORKS_CSB6IDE:
  	case PCI_DEVICE_ID_SERVERWORKS_CSB6IDE2:
  		rc = serverworks_fixup_csb(pdev);
  		break;
  	case PCI_DEVICE_ID_SERVERWORKS_HT1000IDE:
  		serverworks_fixup_ht1000(pdev);
  		break;
  	}
  
  	return rc;
  }

  
  static int serverworks_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
  {

  	static const struct ata_port_info info[4] = {

  		{ /* OSB4 */

  			.flags = ATA_FLAG_SLAVE_POSS,

  			.pio_mask = ATA_PIO4,
  			.mwdma_mask = ATA_MWDMA2,
  			.udma_mask = ATA_UDMA2,

  			.port_ops = &serverworks_osb4_port_ops
  		}, { /* OSB4 no UDMA */

  			.flags = ATA_FLAG_SLAVE_POSS,

  			.pio_mask = ATA_PIO4,
  			.mwdma_mask = ATA_MWDMA2,
  			/* No UDMA */

  			.port_ops = &serverworks_osb4_port_ops
  		}, { /* CSB5 */

  			.flags = ATA_FLAG_SLAVE_POSS,

  			.pio_mask = ATA_PIO4,
  			.mwdma_mask = ATA_MWDMA2,

  			.udma_mask = ATA_UDMA4,

  			.port_ops = &serverworks_csb_port_ops
  		}, { /* CSB5 - later revisions*/

  			.flags = ATA_FLAG_SLAVE_POSS,

  			.pio_mask = ATA_PIO4,
  			.mwdma_mask = ATA_MWDMA2,

  			.udma_mask = ATA_UDMA5,

  			.port_ops = &serverworks_csb_port_ops
  		}
  	};

  	const struct ata_port_info *ppi[] = { &info[id->driver_data], NULL };

  	int rc;
  
  	rc = pcim_enable_device(pdev);
  	if (rc)
  		return rc;

  	rc = serverworks_fixup(pdev);

  
  	/* OSB4 : South Bridge and IDE */
  	if (pdev->device == PCI_DEVICE_ID_SERVERWORKS_OSB4IDE) {
  		/* Select non UDMA capable OSB4 if we can't do fixups */

  		if (rc < 0)

  			ppi[0] = &info[1];

  	}
  	/* setup CSB5/CSB6 : South Bridge and IDE option RAID */
  	else if ((pdev->device == PCI_DEVICE_ID_SERVERWORKS_CSB5IDE) ||
  		 (pdev->device == PCI_DEVICE_ID_SERVERWORKS_CSB6IDE) ||
  		 (pdev->device == PCI_DEVICE_ID_SERVERWORKS_CSB6IDE2)) {

  		 /* If the returned btr is the newer revision then
  		    select the right info block */

  		 if (rc == 3)

  		 	ppi[0] = &info[3];

  		/* Is this the 3rd channel CSB6 IDE ? */
  		if (pdev->device == PCI_DEVICE_ID_SERVERWORKS_CSB6IDE2)

  			ppi[1] = &ata_dummy_port_info;

  	}

  	return ata_pci_bmdma_init_one(pdev, ppi, &serverworks_sht, NULL, 0);

  }

  #ifdef CONFIG_PM

  static int serverworks_reinit_one(struct pci_dev *pdev)
  {

  	struct ata_host *host = dev_get_drvdata(&pdev->dev);
  	int rc;
  
  	rc = ata_pci_device_do_resume(pdev);
  	if (rc)
  		return rc;

  	(void)serverworks_fixup(pdev);

  
  	ata_host_resume(host);
  	return 0;

  }

  #endif

  static const struct pci_device_id serverworks[] = {
  	{ PCI_VDEVICE(SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_OSB4IDE), 0},
  	{ PCI_VDEVICE(SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_CSB5IDE), 2},
  	{ PCI_VDEVICE(SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_CSB6IDE), 2},
  	{ PCI_VDEVICE(SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_CSB6IDE2), 2},
  	{ PCI_VDEVICE(SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_HT1000IDE), 2},
  
  	{ },

  };
  
  static struct pci_driver serverworks_pci_driver = {
  	.name 		= DRV_NAME,
  	.id_table	= serverworks,
  	.probe 		= serverworks_init_one,

  	.remove		= ata_pci_remove_one,

  #ifdef CONFIG_PM

  	.suspend	= ata_pci_device_suspend,
  	.resume		= serverworks_reinit_one,

  #endif

  };
  
  static int __init serverworks_init(void)
  {
  	return pci_register_driver(&serverworks_pci_driver);
  }

  static void __exit serverworks_exit(void)
  {
  	pci_unregister_driver(&serverworks_pci_driver);
  }

  MODULE_AUTHOR("Alan Cox");
  MODULE_DESCRIPTION("low-level driver for Serverworks OSB4/CSB5/CSB6");
  MODULE_LICENSE("GPL");
  MODULE_DEVICE_TABLE(pci, serverworks);
  MODULE_VERSION(DRV_VERSION);
  
  module_init(serverworks_init);
  module_exit(serverworks_exit);