/*
   * pata_atiixp.c 	- ATI PATA for new ATA layer
   *			  (C) 2005 Red Hat Inc

   *			  (C) 2009-2010 Bartlomiej Zolnierkiewicz

   *
   * Based on
   *
   *  linux/drivers/ide/pci/atiixp.c	Version 0.01-bart2	Feb. 26, 2004
   *
   *  Copyright (C) 2003 ATI Inc. <hyu@ati.com>
   *  Copyright (C) 2004 Bartlomiej Zolnierkiewicz
   *
   */
  
  #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_atiixp"

  #define DRV_VERSION "0.4.6"

  
  enum {
  	ATIIXP_IDE_PIO_TIMING	= 0x40,
  	ATIIXP_IDE_MWDMA_TIMING	= 0x44,
  	ATIIXP_IDE_PIO_CONTROL	= 0x48,
  	ATIIXP_IDE_PIO_MODE	= 0x4a,
  	ATIIXP_IDE_UDMA_CONTROL	= 0x54,
  	ATIIXP_IDE_UDMA_MODE 	= 0x56
  };

  static int atiixp_cable_detect(struct ata_port *ap)
  {
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  	u8 udma;
  
  	/* Hack from drivers/ide/pci. Really we want to know how to do the
  	   raw detection not play follow the bios mode guess */
  	pci_read_config_byte(pdev, ATIIXP_IDE_UDMA_MODE + ap->port_no, &udma);
  	if ((udma & 0x07) >= 0x04 || (udma & 0x70) >= 0x40)
  		return  ATA_CBL_PATA80;
  	return ATA_CBL_PATA40;
  }

  static DEFINE_SPINLOCK(atiixp_lock);

  /**

   *	atiixp_prereset	-	perform reset handling
   *	@link: ATA link
   *	@deadline: deadline jiffies for the operation
   *
   *	Reset sequence checking enable bits to see which ports are
   *	active.
   */
  
  static int atiixp_prereset(struct ata_link *link, unsigned long deadline)
  {
  	static const struct pci_bits atiixp_enable_bits[] = {
  		{ 0x48, 1, 0x01, 0x00 },
  		{ 0x48, 1, 0x08, 0x00 }
  	};
  
  	struct ata_port *ap = link->ap;
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  
  	if (!pci_test_config_bits(pdev, &atiixp_enable_bits[ap->port_no]))
  		return -ENOENT;
  
  	return ata_sff_prereset(link, deadline);
  }
  
  /**

   *	atiixp_set_pio_timing	-	set initial PIO mode data
   *	@ap: ATA interface
   *	@adev: ATA device
   *
   *	Called by both the pio and dma setup functions to set the controller
   *	timings for PIO transfers. We must load both the mode number and
   *	timing values into the controller.
   */
  
  static void atiixp_set_pio_timing(struct ata_port *ap, struct ata_device *adev, int pio)
  {
  	static u8 pio_timings[5] = { 0x5D, 0x47, 0x34, 0x22, 0x20 };
  
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  	int dn = 2 * ap->port_no + adev->devno;

  	int timing_shift = (16 * ap->port_no) + 8 * (adev->devno ^ 1);

  	u32 pio_timing_data;
  	u16 pio_mode_data;

  
  	pci_read_config_word(pdev, ATIIXP_IDE_PIO_MODE, &pio_mode_data);
  	pio_mode_data &= ~(0x7 << (4 * dn));
  	pio_mode_data |= pio << (4 * dn);
  	pci_write_config_word(pdev, ATIIXP_IDE_PIO_MODE, pio_mode_data);

  	pci_read_config_dword(pdev, ATIIXP_IDE_PIO_TIMING, &pio_timing_data);

  	pio_timing_data &= ~(0xFF << timing_shift);
  	pio_timing_data |= (pio_timings[pio] << timing_shift);

  	pci_write_config_dword(pdev, ATIIXP_IDE_PIO_TIMING, pio_timing_data);

  }
  
  /**
   *	atiixp_set_piomode	-	set initial PIO mode data
   *	@ap: ATA interface
   *	@adev: ATA device
   *
   *	Called to do the PIO mode setup. We use a shared helper for this
   *	as the DMA setup must also adjust the PIO timing information.
   */
  
  static void atiixp_set_piomode(struct ata_port *ap, struct ata_device *adev)
  {

  	unsigned long flags;
  	spin_lock_irqsave(&atiixp_lock, flags);

  	atiixp_set_pio_timing(ap, adev, adev->pio_mode - XFER_PIO_0);

  	spin_unlock_irqrestore(&atiixp_lock, flags);

  }
  
  /**
   *	atiixp_set_dmamode	-	set initial DMA mode data
   *	@ap: ATA interface
   *	@adev: ATA device
   *
   *	Called to do the DMA mode setup. We use timing tables for most
   *	modes but must tune an appropriate PIO mode to match.
   */
  
  static void atiixp_set_dmamode(struct ata_port *ap, struct ata_device *adev)
  {
  	static u8 mwdma_timings[5] = { 0x77, 0x21, 0x20 };
  
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  	int dma = adev->dma_mode;
  	int dn = 2 * ap->port_no + adev->devno;
  	int wanted_pio;

  	unsigned long flags;
  
  	spin_lock_irqsave(&atiixp_lock, flags);

  
  	if (adev->dma_mode >= XFER_UDMA_0) {
  		u16 udma_mode_data;
  
  		dma -= XFER_UDMA_0;
  
  		pci_read_config_word(pdev, ATIIXP_IDE_UDMA_MODE, &udma_mode_data);
  		udma_mode_data &= ~(0x7 << (4 * dn));
  		udma_mode_data |= dma << (4 * dn);
  		pci_write_config_word(pdev, ATIIXP_IDE_UDMA_MODE, udma_mode_data);
  	} else {

  		int timing_shift = (16 * ap->port_no) + 8 * (adev->devno ^ 1);

  		u32 mwdma_timing_data;

  
  		dma -= XFER_MW_DMA_0;

  		pci_read_config_dword(pdev, ATIIXP_IDE_MWDMA_TIMING,
  				      &mwdma_timing_data);

  		mwdma_timing_data &= ~(0xFF << timing_shift);
  		mwdma_timing_data |= (mwdma_timings[dma] << timing_shift);

  		pci_write_config_dword(pdev, ATIIXP_IDE_MWDMA_TIMING,
  				       mwdma_timing_data);

  	}
  	/*
  	 *	We must now look at the PIO mode situation. We may need to
  	 *	adjust the PIO mode to keep the timings acceptable
  	 */
  	 if (adev->dma_mode >= XFER_MW_DMA_2)
  	 	wanted_pio = 4;
  	else if (adev->dma_mode == XFER_MW_DMA_1)
  		wanted_pio = 3;
  	else if (adev->dma_mode == XFER_MW_DMA_0)
  		wanted_pio = 0;
  	else BUG();
  
  	if (adev->pio_mode != wanted_pio)
  		atiixp_set_pio_timing(ap, adev, wanted_pio);

  	spin_unlock_irqrestore(&atiixp_lock, flags);

  }
  
  /**
   *	atiixp_bmdma_start	-	DMA start callback
   *	@qc: Command in progress
   *
   *	When DMA begins we need to ensure that the UDMA control
   *	register for the channel is correctly set.

   *
   *	Note: The host lock held by the libata layer protects
   *	us from two channels both trying to set DMA bits at once

   */
  
  static void atiixp_bmdma_start(struct ata_queued_cmd *qc)
  {
  	struct ata_port *ap = qc->ap;
  	struct ata_device *adev = qc->dev;
  
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  	int dn = (2 * ap->port_no) + adev->devno;
  	u16 tmp16;
  
  	pci_read_config_word(pdev, ATIIXP_IDE_UDMA_CONTROL, &tmp16);

  	if (ata_using_udma(adev))

  		tmp16 |= (1 << dn);
  	else
  		tmp16 &= ~(1 << dn);
  	pci_write_config_word(pdev, ATIIXP_IDE_UDMA_CONTROL, tmp16);
  	ata_bmdma_start(qc);
  }
  
  /**
   *	atiixp_dma_stop	-	DMA stop callback
   *	@qc: Command in progress
   *
   *	DMA has completed. Clear the UDMA flag as the next operations will
   *	be PIO ones not UDMA data transfer.

   *
   *	Note: The host lock held by the libata layer protects
   *	us from two channels both trying to set DMA bits at once

   */
  
  static void atiixp_bmdma_stop(struct ata_queued_cmd *qc)
  {
  	struct ata_port *ap = qc->ap;
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  	int dn = (2 * ap->port_no) + qc->dev->devno;
  	u16 tmp16;
  
  	pci_read_config_word(pdev, ATIIXP_IDE_UDMA_CONTROL, &tmp16);
  	tmp16 &= ~(1 << dn);
  	pci_write_config_word(pdev, ATIIXP_IDE_UDMA_CONTROL, tmp16);
  	ata_bmdma_stop(qc);
  }
  
  static struct scsi_host_template atiixp_sht = {

  	ATA_BMDMA_SHT(DRV_NAME),

  	.sg_tablesize		= LIBATA_DUMB_MAX_PRD,

  };
  
  static struct ata_port_operations atiixp_port_ops = {

  	.inherits	= &ata_bmdma_port_ops,

  	.qc_prep 	= ata_bmdma_dumb_qc_prep,

  	.bmdma_start 	= atiixp_bmdma_start,
  	.bmdma_stop	= atiixp_bmdma_stop,

  	.prereset	= atiixp_prereset,

  	.cable_detect	= atiixp_cable_detect,
  	.set_piomode	= atiixp_set_piomode,
  	.set_dmamode	= atiixp_set_dmamode,

  };

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

  {

  	static const struct ata_port_info info = {

  		.flags = ATA_FLAG_SLAVE_POSS,

  		.pio_mask = ATA_PIO4,
  		.mwdma_mask = ATA_MWDMA12_ONLY,
  		.udma_mask = ATA_UDMA5,

  		.port_ops = &atiixp_port_ops
  	};

  	const struct ata_port_info *ppi[] = { &info, &info };

  	return ata_pci_bmdma_init_one(pdev, ppi, &atiixp_sht, NULL,
  				      ATA_HOST_PARALLEL_SCAN);

  }

  static const struct pci_device_id atiixp[] = {
  	{ PCI_VDEVICE(ATI, PCI_DEVICE_ID_ATI_IXP200_IDE), },
  	{ PCI_VDEVICE(ATI, PCI_DEVICE_ID_ATI_IXP300_IDE), },
  	{ PCI_VDEVICE(ATI, PCI_DEVICE_ID_ATI_IXP400_IDE), },
  	{ PCI_VDEVICE(ATI, PCI_DEVICE_ID_ATI_IXP600_IDE), },

  	{ PCI_VDEVICE(ATI, PCI_DEVICE_ID_ATI_IXP700_IDE), },

  	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_HUDSON2_IDE), },

  
  	{ },

  };
  
  static struct pci_driver atiixp_pci_driver = {
  	.name 		= DRV_NAME,
  	.id_table	= atiixp,
  	.probe 		= atiixp_init_one,

  	.remove		= ata_pci_remove_one,

  #ifdef CONFIG_PM

  	.resume		= ata_pci_device_resume,
  	.suspend	= ata_pci_device_suspend,

  #endif

  };
  
  static int __init atiixp_init(void)
  {
  	return pci_register_driver(&atiixp_pci_driver);
  }
  
  
  static void __exit atiixp_exit(void)
  {
  	pci_unregister_driver(&atiixp_pci_driver);
  }

  MODULE_AUTHOR("Alan Cox");
  MODULE_DESCRIPTION("low-level driver for ATI IXP200/300/400");
  MODULE_LICENSE("GPL");
  MODULE_DEVICE_TABLE(pci, atiixp);
  MODULE_VERSION(DRV_VERSION);
  
  module_init(atiixp_init);
  module_exit(atiixp_exit);