/*
   *	IDE tuning and bus mastering support for the CS5510/CS5520
   *	chipsets
   *
   *	The CS5510/CS5520 are slightly unusual devices. Unlike the
   *	typical IDE controllers they do bus mastering with the drive in
   *	PIO mode and smarter silicon.
   *
   *	The practical upshot of this is that we must always tune the
   *	drive for the right PIO mode. We must also ignore all the blacklists
   *	and the drive bus mastering DMA information. Also to confuse matters
   *	further we can do DMA on PIO only drives.
   *
   *	DMA on the 5510 also requires we disable_hlt() during DMA on early
   *	revisions.
   *
   *	*** This driver is strictly experimental ***
   *
   *	(c) Copyright Red Hat Inc 2002
   *
   * 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, or (at your option) any
   * later version.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   *
   * Documentation:
   *	Not publically available.
   */
  #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_cs5520"

  #define DRV_VERSION	"0.6.6"

  
  struct pio_clocks
  {
  	int address;
  	int assert;
  	int recovery;
  };
  
  static const struct pio_clocks cs5520_pio_clocks[]={
  	{3, 6, 11},
  	{2, 5, 6},
  	{1, 4, 3},
  	{1, 3, 2},
  	{1, 2, 1}
  };
  
  /**
   *	cs5520_set_timings	-	program PIO timings
   *	@ap: ATA port
   *	@adev: ATA device
   *
   *	Program the PIO mode timings for the controller according to the pio
   *	clocking table.
   */
  
  static void cs5520_set_timings(struct ata_port *ap, struct ata_device *adev, int pio)
  {
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  	int slave = adev->devno;
  
  	pio -= XFER_PIO_0;
  
  	/* Channel command timing */
  	pci_write_config_byte(pdev, 0x62 + ap->port_no,
  				(cs5520_pio_clocks[pio].recovery << 4) |
  				(cs5520_pio_clocks[pio].assert));
  	/* FIXME: should these use address ? */
  	/* Read command timing */
  	pci_write_config_byte(pdev, 0x64 +  4*ap->port_no + slave,
  				(cs5520_pio_clocks[pio].recovery << 4) |
  				(cs5520_pio_clocks[pio].assert));
  	/* Write command timing */
  	pci_write_config_byte(pdev, 0x66 +  4*ap->port_no + slave,
  				(cs5520_pio_clocks[pio].recovery << 4) |
  				(cs5520_pio_clocks[pio].assert));
  }
  
  /**
   *	cs5520_enable_dma	-	turn on DMA bits
   *
   *	Turn on the DMA bits for this disk. Needed because the BIOS probably
   *	has not done the work for us. Belongs in the core SATA code.
   */
  
  static void cs5520_enable_dma(struct ata_port *ap, struct ata_device *adev)
  {
  	/* Set the DMA enable/disable flag */

  	u8 reg = ioread8(ap->ioaddr.bmdma_addr + 0x02);

  	reg |= 1<<(adev->devno + 5);

  	iowrite8(reg, ap->ioaddr.bmdma_addr + 0x02);

  }
  
  /**
   *	cs5520_set_dmamode	-	program DMA timings
   *	@ap: ATA port
   *	@adev: ATA device
   *
   *	Program the DMA mode timings for the controller according to the pio
   *	clocking table. Note that this device sets the DMA timings to PIO
   *	mode values. This may seem bizarre but the 5520 architecture talks
   *	PIO mode to the disk and DMA mode to the controller so the underlying
   *	transfers are PIO timed.
   */
  
  static void cs5520_set_dmamode(struct ata_port *ap, struct ata_device *adev)
  {
  	static const int dma_xlate[3] = { XFER_PIO_0, XFER_PIO_3, XFER_PIO_4 };
  	cs5520_set_timings(ap, adev, dma_xlate[adev->dma_mode]);
  	cs5520_enable_dma(ap, adev);
  }
  
  /**
   *	cs5520_set_piomode	-	program PIO timings
   *	@ap: ATA port
   *	@adev: ATA device
   *
   *	Program the PIO mode timings for the controller according to the pio
   *	clocking table. We know pio_mode will equal dma_mode because of the
   *	CS5520 architecture. At least once we turned DMA on and wrote a
   *	mode setter.
   */
  
  static void cs5520_set_piomode(struct ata_port *ap, struct ata_device *adev)
  {
  	cs5520_set_timings(ap, adev, adev->pio_mode);
  }

  static struct scsi_host_template cs5520_sht = {

  	ATA_BMDMA_SHT(DRV_NAME),

  	.sg_tablesize		= LIBATA_DUMB_MAX_PRD,

  };
  
  static struct ata_port_operations cs5520_port_ops = {

  	.inherits		= &ata_bmdma_port_ops,

  	.qc_prep		= ata_sff_dumb_qc_prep,

  	.cable_detect		= ata_cable_40wire,

  	.set_piomode		= cs5520_set_piomode,
  	.set_dmamode		= cs5520_set_dmamode,

  };

  static int __devinit cs5520_init_one(struct pci_dev *pdev, const struct pci_device_id *id)

  {

  	static const unsigned int cmd_port[] = { 0x1F0, 0x170 };
  	static const unsigned int ctl_port[] = { 0x3F6, 0x376 };

  	struct ata_port_info pi = {
  		.flags		= ATA_FLAG_SLAVE_POSS,

  		.pio_mask	= ATA_PIO4,

  		.port_ops	= &cs5520_port_ops,
  	};
  	const struct ata_port_info *ppi[2];

  	u8 pcicfg;

  	void __iomem *iomap[5];

  	struct ata_host *host;
  	struct ata_ioports *ioaddr;
  	int i, rc;

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

  	/* IDE port enable bits */

  	pci_read_config_byte(pdev, 0x60, &pcicfg);

  
  	/* Check if the ATA ports are enabled */
  	if ((pcicfg & 3) == 0)
  		return -ENODEV;

  	ppi[0] = ppi[1] = &ata_dummy_port_info;
  	if (pcicfg & 1)
  		ppi[0] = π
  	if (pcicfg & 2)
  		ppi[1] = π

  	if ((pcicfg & 0x40) == 0) {

  		dev_printk(KERN_WARNING, &pdev->dev,
  			   "DMA mode disabled. Enabling.
  ");
  		pci_write_config_byte(pdev, 0x60, pcicfg | 0x40);

  	}

  	pi.mwdma_mask = id->driver_data;
  
  	host = ata_host_alloc_pinfo(&pdev->dev, ppi, 2);
  	if (!host)
  		return -ENOMEM;

  	/* Perform set up for DMA */

  	if (pci_enable_device_io(pdev)) {

  		printk(KERN_ERR DRV_NAME ": unable to configure BAR2.
  ");
  		return -ENODEV;
  	}

  
  	if (pci_set_dma_mask(pdev, DMA_32BIT_MASK)) {

  		printk(KERN_ERR DRV_NAME ": unable to configure DMA mask.
  ");
  		return -ENODEV;
  	}

  	if (pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK)) {

  		printk(KERN_ERR DRV_NAME ": unable to configure consistent DMA mask.
  ");
  		return -ENODEV;
  	}

  	/* Map IO ports and initialize host accordingly */

  	iomap[0] = devm_ioport_map(&pdev->dev, cmd_port[0], 8);
  	iomap[1] = devm_ioport_map(&pdev->dev, ctl_port[0], 1);
  	iomap[2] = devm_ioport_map(&pdev->dev, cmd_port[1], 8);
  	iomap[3] = devm_ioport_map(&pdev->dev, ctl_port[1], 1);

  	iomap[4] = pcim_iomap(pdev, 2, 0);

  
  	if (!iomap[0] || !iomap[1] || !iomap[2] || !iomap[3] || !iomap[4])
  		return -ENOMEM;

  	ioaddr = &host->ports[0]->ioaddr;
  	ioaddr->cmd_addr = iomap[0];
  	ioaddr->ctl_addr = iomap[1];
  	ioaddr->altstatus_addr = iomap[1];
  	ioaddr->bmdma_addr = iomap[4];

  	ata_sff_std_ports(ioaddr);

  	ata_port_desc(host->ports[0],
  		      "cmd 0x%x ctl 0x%x", cmd_port[0], ctl_port[0]);
  	ata_port_pbar_desc(host->ports[0], 4, 0, "bmdma");

  	ioaddr = &host->ports[1]->ioaddr;
  	ioaddr->cmd_addr = iomap[2];
  	ioaddr->ctl_addr = iomap[3];
  	ioaddr->altstatus_addr = iomap[3];
  	ioaddr->bmdma_addr = iomap[4] + 8;

  	ata_sff_std_ports(ioaddr);

  	ata_port_desc(host->ports[1],
  		      "cmd 0x%x ctl 0x%x", cmd_port[1], ctl_port[1]);
  	ata_port_pbar_desc(host->ports[1], 4, 8, "bmdma");

  	/* activate the host */
  	pci_set_master(pdev);
  	rc = ata_host_start(host);
  	if (rc)
  		return rc;
  
  	for (i = 0; i < 2; i++) {
  		static const int irq[] = { 14, 15 };

  		struct ata_port *ap = host->ports[i];

  
  		if (ata_port_is_dummy(ap))
  			continue;
  
  		rc = devm_request_irq(&pdev->dev, irq[ap->port_no],

  				      ata_sff_interrupt, 0, DRV_NAME, host);

  		if (rc)
  			return rc;

  		ata_port_desc(ap, "irq %d", irq[i]);

  	}
  
  	return ata_host_register(host, &cs5520_sht);

  }

  #ifdef CONFIG_PM

  /**
   *	cs5520_reinit_one	-	device resume
   *	@pdev: PCI device
   *
   *	Do any reconfiguration work needed by a resume from RAM. We need
   *	to restore DMA mode support on BIOSen which disabled it
   */

  static int cs5520_reinit_one(struct pci_dev *pdev)
  {

  	struct ata_host *host = dev_get_drvdata(&pdev->dev);

  	u8 pcicfg;

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

  	pci_read_config_byte(pdev, 0x60, &pcicfg);
  	if ((pcicfg & 0x40) == 0)
  		pci_write_config_byte(pdev, 0x60, pcicfg | 0x40);

  
  	ata_host_resume(host);
  	return 0;

  }

  
  /**
   *	cs5520_pci_device_suspend	-	device suspend
   *	@pdev: PCI device
   *
   *	We have to cut and waste bits from the standard method because
   *	the 5520 is a bit odd and not just a pure ATA device. As a result
   *	we must not disable it. The needed code is short and this avoids
   *	chip specific mess in the core code.
   */
  
  static int cs5520_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
  {
  	struct ata_host *host = dev_get_drvdata(&pdev->dev);
  	int rc = 0;
  
  	rc = ata_host_suspend(host, mesg);
  	if (rc)
  		return rc;
  
  	pci_save_state(pdev);
  	return 0;
  }

  #endif /* CONFIG_PM */

  /* For now keep DMA off. We can set it for all but A rev CS5510 once the
     core ATA code can handle it */

  static const struct pci_device_id pata_cs5520[] = {
  	{ PCI_VDEVICE(CYRIX, PCI_DEVICE_ID_CYRIX_5510), },
  	{ PCI_VDEVICE(CYRIX, PCI_DEVICE_ID_CYRIX_5520), },
  
  	{ },

  };
  
  static struct pci_driver cs5520_pci_driver = {
  	.name 		= DRV_NAME,
  	.id_table	= pata_cs5520,
  	.probe 		= cs5520_init_one,

  	.remove		= ata_pci_remove_one,

  #ifdef CONFIG_PM

  	.suspend	= cs5520_pci_device_suspend,

  	.resume		= cs5520_reinit_one,

  #endif

  };

  static int __init cs5520_init(void)
  {
  	return pci_register_driver(&cs5520_pci_driver);
  }
  
  static void __exit cs5520_exit(void)
  {
  	pci_unregister_driver(&cs5520_pci_driver);
  }
  
  MODULE_AUTHOR("Alan Cox");
  MODULE_DESCRIPTION("low-level driver for Cyrix CS5510/5520");
  MODULE_LICENSE("GPL");
  MODULE_DEVICE_TABLE(pci, pata_cs5520);
  MODULE_VERSION(DRV_VERSION);
  
  module_init(cs5520_init);
  module_exit(cs5520_exit);