/*
   * pata_atp867x.c - ARTOP 867X 64bit 4-channel UDMA133 ATA controller driver
   *
   *	(C) 2009 Google Inc. John(Jung-Ik) Lee <jilee@google.com>
   *
   * Per Atp867 data sheet rev 1.2, Acard.
   * Based in part on early ide code from
   *	2003-2004 by Eric Uhrhane, Google, Inc.
   *
   * 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.
   *
   * 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.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
   *
   *
   * TODO:
   *   1. RAID features [comparison, XOR, striping, mirroring, etc.]
   */
  
  #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 <linux/gfp.h>

  #include <scsi/scsi_host.h>
  #include <linux/libata.h>
  
  #define	DRV_NAME	"pata_atp867x"
  #define	DRV_VERSION	"0.7.5"
  
  /*
   * IO Registers
   * Note that all runtime hot priv ports are cached in ap private_data
   */
  
  enum {
  	ATP867X_IO_CHANNEL_OFFSET	= 0x10,
  
  	/*
  	 * IO Register Bitfields
  	 */
  
  	ATP867X_IO_PIOSPD_ACTIVE_SHIFT	= 4,
  	ATP867X_IO_PIOSPD_RECOVER_SHIFT	= 0,
  
  	ATP867X_IO_DMAMODE_MSTR_SHIFT	= 0,
  	ATP867X_IO_DMAMODE_MSTR_MASK	= 0x07,
  	ATP867X_IO_DMAMODE_SLAVE_SHIFT	= 4,
  	ATP867X_IO_DMAMODE_SLAVE_MASK	= 0x70,
  
  	ATP867X_IO_DMAMODE_UDMA_6	= 0x07,
  	ATP867X_IO_DMAMODE_UDMA_5	= 0x06,
  	ATP867X_IO_DMAMODE_UDMA_4	= 0x05,
  	ATP867X_IO_DMAMODE_UDMA_3	= 0x04,
  	ATP867X_IO_DMAMODE_UDMA_2	= 0x03,
  	ATP867X_IO_DMAMODE_UDMA_1	= 0x02,
  	ATP867X_IO_DMAMODE_UDMA_0	= 0x01,
  	ATP867X_IO_DMAMODE_DISABLE	= 0x00,
  
  	ATP867X_IO_SYS_INFO_66MHZ	= 0x04,
  	ATP867X_IO_SYS_INFO_SLOW_UDMA5	= 0x02,
  	ATP867X_IO_SYS_MASK_RESERVED	= (~0xf1),
  
  	ATP867X_IO_PORTSPD_VAL		= 0x1143,
  	ATP867X_PREREAD_VAL		= 0x0200,
  
  	ATP867X_NUM_PORTS		= 4,
  	ATP867X_BAR_IOBASE		= 0,
  	ATP867X_BAR_ROMBASE		= 6,
  };
  
  #define ATP867X_IOBASE(ap)		((ap)->host->iomap[0])
  #define ATP867X_SYS_INFO(ap)		(0x3F + ATP867X_IOBASE(ap))
  
  #define ATP867X_IO_PORTBASE(ap, port)	(0x00 + ATP867X_IOBASE(ap) + \
  					(port) * ATP867X_IO_CHANNEL_OFFSET)
  #define ATP867X_IO_DMABASE(ap, port)	(0x40 + \
  					ATP867X_IO_PORTBASE((ap), (port)))
  
  #define ATP867X_IO_STATUS(ap, port)	(0x07 + \
  					ATP867X_IO_PORTBASE((ap), (port)))
  #define ATP867X_IO_ALTSTATUS(ap, port)	(0x0E + \
  					ATP867X_IO_PORTBASE((ap), (port)))
  
  /*
   * hot priv ports
   */
  #define ATP867X_IO_MSTRPIOSPD(ap, port)	(0x08 + \
  					ATP867X_IO_DMABASE((ap), (port)))
  #define ATP867X_IO_SLAVPIOSPD(ap, port)	(0x09 + \
  					ATP867X_IO_DMABASE((ap), (port)))
  #define ATP867X_IO_8BPIOSPD(ap, port)	(0x0A + \
  					ATP867X_IO_DMABASE((ap), (port)))
  #define ATP867X_IO_DMAMODE(ap, port)	(0x0B + \
  					ATP867X_IO_DMABASE((ap), (port)))
  
  #define ATP867X_IO_PORTSPD(ap, port)	(0x4A + \
  					ATP867X_IO_PORTBASE((ap), (port)))
  #define ATP867X_IO_PREREAD(ap, port)	(0x4C + \
  					ATP867X_IO_PORTBASE((ap), (port)))
  
  struct atp867x_priv {
  	void __iomem *dma_mode;
  	void __iomem *mstr_piospd;
  	void __iomem *slave_piospd;
  	void __iomem *eightb_piospd;
  	int		pci66mhz;
  };

  static void atp867x_set_dmamode(struct ata_port *ap, struct ata_device *adev)
  {
  	struct pci_dev *pdev	= to_pci_dev(ap->host->dev);
  	struct atp867x_priv *dp = ap->private_data;
  	u8 speed = adev->dma_mode;
  	u8 b;

  	u8 mode = speed - XFER_UDMA_0 + 1;

  
  	/*
  	 * Doc 6.6.9: decrease the udma mode value by 1 for safer UDMA speed
  	 * on 66MHz bus
  	 *   rev-A: UDMA_1~4 (5, 6 no change)
  	 *   rev-B: all UDMA modes
  	 *   UDMA_0 stays not to disable UDMA
  	 */
  	if (dp->pci66mhz && mode > ATP867X_IO_DMAMODE_UDMA_0  &&
  	   (pdev->device == PCI_DEVICE_ID_ARTOP_ATP867B ||
  	    mode < ATP867X_IO_DMAMODE_UDMA_5))
  		mode--;
  
  	b = ioread8(dp->dma_mode);
  	if (adev->devno & 1) {
  		b = (b & ~ATP867X_IO_DMAMODE_SLAVE_MASK) |
  			(mode << ATP867X_IO_DMAMODE_SLAVE_SHIFT);
  	} else {
  		b = (b & ~ATP867X_IO_DMAMODE_MSTR_MASK) |
  			(mode << ATP867X_IO_DMAMODE_MSTR_SHIFT);
  	}
  	iowrite8(b, dp->dma_mode);
  }

  static int atp867x_get_active_clocks_shifted(struct ata_port *ap,
  	unsigned int clk)

  {

  	struct atp867x_priv *dp = ap->private_data;

  	unsigned char clocks = clk;

  	/*
  	 * Doc 6.6.9: increase the clock value by 1 for safer PIO speed
  	 * on 66MHz bus
  	 */
  	if (dp->pci66mhz)
  		clocks++;

  	switch (clocks) {
  	case 0:
  		clocks = 1;
  		break;

  	case 1 ... 6:

  		break;
  	default:
  		printk(KERN_WARNING "ATP867X: active %dclk is invalid. "

  			"Using 12clk.
  ", clk);
  	case 9 ... 12:
  		clocks = 7;	/* 12 clk */
  		break;
  	case 7:

  	case 8:	/* default 8 clk */
  		clocks = 0;
  		goto active_clock_shift_done;

  	}

  active_clock_shift_done:

  	return clocks << ATP867X_IO_PIOSPD_ACTIVE_SHIFT;
  }
  
  static int atp867x_get_recover_clocks_shifted(unsigned int clk)
  {
  	unsigned char clocks = clk;
  
  	switch (clocks) {
  	case 0:
  		clocks = 1;
  		break;
  	case 1 ... 11:
  		break;

  	case 13:
  	case 14:

  		--clocks;	/* by the spec */

  		break;
  	case 15:
  		break;
  	default:
  		printk(KERN_WARNING "ATP867X: recover %dclk is invalid. "

  			"Using default 12clk.
  ", clk);
  	case 12:	/* default 12 clk */
  		clocks = 0;

  		break;
  	}

  	return clocks << ATP867X_IO_PIOSPD_RECOVER_SHIFT;
  }
  
  static void atp867x_set_piomode(struct ata_port *ap, struct ata_device *adev)
  {
  	struct ata_device *peer = ata_dev_pair(adev);
  	struct atp867x_priv *dp = ap->private_data;
  	u8 speed = adev->pio_mode;
  	struct ata_timing t, p;
  	int T, UT;
  	u8 b;
  
  	T = 1000000000 / 33333;
  	UT = T / 4;
  
  	ata_timing_compute(adev, speed, &t, T, UT);
  	if (peer && peer->pio_mode) {
  		ata_timing_compute(peer, peer->pio_mode, &p, T, UT);
  		ata_timing_merge(&p, &t, &t, ATA_TIMING_8BIT);
  	}
  
  	b = ioread8(dp->dma_mode);
  	if (adev->devno & 1)
  		b = (b & ~ATP867X_IO_DMAMODE_SLAVE_MASK);
  	else
  		b = (b & ~ATP867X_IO_DMAMODE_MSTR_MASK);
  	iowrite8(b, dp->dma_mode);

  	b = atp867x_get_active_clocks_shifted(ap, t.active) |

  	    atp867x_get_recover_clocks_shifted(t.recover);

  
  	if (adev->devno & 1)
  		iowrite8(b, dp->slave_piospd);
  	else
  		iowrite8(b, dp->mstr_piospd);

  	b = atp867x_get_active_clocks_shifted(ap, t.act8b) |
  	    atp867x_get_recover_clocks_shifted(t.rec8b);

  	iowrite8(b, dp->eightb_piospd);
  }

  static int atp867x_cable_override(struct pci_dev *pdev)
  {
  	if (pdev->subsystem_vendor == PCI_VENDOR_ID_ARTOP &&
  		(pdev->subsystem_device == PCI_DEVICE_ID_ARTOP_ATP867A ||
  		 pdev->subsystem_device == PCI_DEVICE_ID_ARTOP_ATP867B)) {
  		return 1;
  	}
  	return 0;
  }

  static int atp867x_cable_detect(struct ata_port *ap)
  {

  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  
  	if (atp867x_cable_override(pdev))
  		return ATA_CBL_PATA40_SHORT;
  
  	return ATA_CBL_PATA_UNK;

  }
  
  static struct scsi_host_template atp867x_sht = {
  	ATA_BMDMA_SHT(DRV_NAME),
  };
  
  static struct ata_port_operations atp867x_ops = {
  	.inherits		= &ata_bmdma_port_ops,
  	.cable_detect		= atp867x_cable_detect,
  	.set_piomode		= atp867x_set_piomode,
  	.set_dmamode		= atp867x_set_dmamode,
  };
  
  
  #ifdef	ATP867X_DEBUG
  static void atp867x_check_res(struct pci_dev *pdev)
  {
  	int i;
  	unsigned long start, len;
  
  	/* Check the PCI resources for this channel are enabled */
  	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
  		start = pci_resource_start(pdev, i);
  		len   = pci_resource_len(pdev, i);
  		printk(KERN_DEBUG "ATP867X: resource start:len=%lx:%lx
  ",
  			start, len);
  	}
  }
  
  static void atp867x_check_ports(struct ata_port *ap, int port)
  {
  	struct ata_ioports *ioaddr = &ap->ioaddr;
  	struct atp867x_priv *dp = ap->private_data;
  
  	printk(KERN_DEBUG "ATP867X: port[%d] addresses
  "
  		"  cmd_addr	=0x%llx, 0x%llx
  "
  		"  ctl_addr	=0x%llx, 0x%llx
  "
  		"  bmdma_addr	=0x%llx, 0x%llx
  "
  		"  data_addr	=0x%llx
  "
  		"  error_addr	=0x%llx
  "
  		"  feature_addr	=0x%llx
  "
  		"  nsect_addr	=0x%llx
  "
  		"  lbal_addr	=0x%llx
  "
  		"  lbam_addr	=0x%llx
  "
  		"  lbah_addr	=0x%llx
  "
  		"  device_addr	=0x%llx
  "
  		"  status_addr	=0x%llx
  "
  		"  command_addr	=0x%llx
  "
  		"  dp->dma_mode	=0x%llx
  "
  		"  dp->mstr_piospd	=0x%llx
  "
  		"  dp->slave_piospd	=0x%llx
  "
  		"  dp->eightb_piospd	=0x%llx
  "
  		"  dp->pci66mhz		=0x%lx
  ",
  		port,
  		(unsigned long long)ioaddr->cmd_addr,
  		(unsigned long long)ATP867X_IO_PORTBASE(ap, port),
  		(unsigned long long)ioaddr->ctl_addr,
  		(unsigned long long)ATP867X_IO_ALTSTATUS(ap, port),
  		(unsigned long long)ioaddr->bmdma_addr,
  		(unsigned long long)ATP867X_IO_DMABASE(ap, port),
  		(unsigned long long)ioaddr->data_addr,
  		(unsigned long long)ioaddr->error_addr,
  		(unsigned long long)ioaddr->feature_addr,
  		(unsigned long long)ioaddr->nsect_addr,
  		(unsigned long long)ioaddr->lbal_addr,
  		(unsigned long long)ioaddr->lbam_addr,
  		(unsigned long long)ioaddr->lbah_addr,
  		(unsigned long long)ioaddr->device_addr,
  		(unsigned long long)ioaddr->status_addr,
  		(unsigned long long)ioaddr->command_addr,
  		(unsigned long long)dp->dma_mode,
  		(unsigned long long)dp->mstr_piospd,
  		(unsigned long long)dp->slave_piospd,
  		(unsigned long long)dp->eightb_piospd,
  		(unsigned long)dp->pci66mhz);
  }
  #endif
  
  static int atp867x_set_priv(struct ata_port *ap)
  {
  	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  	struct atp867x_priv *dp;
  	int port = ap->port_no;
  
  	dp = ap->private_data =
  		devm_kzalloc(&pdev->dev, sizeof(*dp), GFP_KERNEL);
  	if (dp == NULL)
  		return -ENOMEM;
  
  	dp->dma_mode	 = ATP867X_IO_DMAMODE(ap, port);
  	dp->mstr_piospd	 = ATP867X_IO_MSTRPIOSPD(ap, port);
  	dp->slave_piospd = ATP867X_IO_SLAVPIOSPD(ap, port);
  	dp->eightb_piospd = ATP867X_IO_8BPIOSPD(ap, port);
  
  	dp->pci66mhz =
  		ioread8(ATP867X_SYS_INFO(ap)) & ATP867X_IO_SYS_INFO_66MHZ;
  
  	return 0;
  }
  
  static void atp867x_fixup(struct ata_host *host)
  {
  	struct pci_dev *pdev = to_pci_dev(host->dev);
  	struct ata_port *ap = host->ports[0];
  	int i;
  	u8 v;
  
  	/*
  	 * Broken BIOS might not set latency high enough
  	 */
  	pci_read_config_byte(pdev, PCI_LATENCY_TIMER, &v);
  	if (v < 0x80) {
  		v = 0x80;
  		pci_write_config_byte(pdev, PCI_LATENCY_TIMER, v);
  		printk(KERN_DEBUG "ATP867X: set latency timer of device %s"
  			" to %d
  ", pci_name(pdev), v);
  	}
  
  	/*
  	 * init 8bit io ports speed(0aaarrrr) to 43h and
  	 * init udma modes of master/slave to 0/0(11h)
  	 */
  	for (i = 0; i < ATP867X_NUM_PORTS; i++)
  		iowrite16(ATP867X_IO_PORTSPD_VAL, ATP867X_IO_PORTSPD(ap, i));
  
  	/*
  	 * init PreREAD counts
  	 */
  	for (i = 0; i < ATP867X_NUM_PORTS; i++)
  		iowrite16(ATP867X_PREREAD_VAL, ATP867X_IO_PREREAD(ap, i));
  
  	v = ioread8(ATP867X_IOBASE(ap) + 0x28);
  	v &= 0xcf;	/* Enable INTA#: bit4=0 means enable */
  	v |= 0xc0;	/* Enable PCI burst, MRM & not immediate interrupts */
  	iowrite8(v, ATP867X_IOBASE(ap) + 0x28);
  
  	/*
  	 * Turn off the over clocked udma5 mode, only for Rev-B
  	 */
  	v = ioread8(ATP867X_SYS_INFO(ap));
  	v &= ATP867X_IO_SYS_MASK_RESERVED;
  	if (pdev->device == PCI_DEVICE_ID_ARTOP_ATP867B)
  		v |= ATP867X_IO_SYS_INFO_SLOW_UDMA5;
  	iowrite8(v, ATP867X_SYS_INFO(ap));
  }
  
  static int atp867x_ata_pci_sff_init_host(struct ata_host *host)
  {
  	struct device *gdev = host->dev;
  	struct pci_dev *pdev = to_pci_dev(gdev);
  	unsigned int mask = 0;
  	int i, rc;
  
  	/*
  	 * do not map rombase
  	 */
  	rc = pcim_iomap_regions(pdev, 1 << ATP867X_BAR_IOBASE, DRV_NAME);
  	if (rc == -EBUSY)
  		pcim_pin_device(pdev);
  	if (rc)
  		return rc;
  	host->iomap = pcim_iomap_table(pdev);
  
  #ifdef	ATP867X_DEBUG
  	atp867x_check_res(pdev);
  
  	for (i = 0; i < PCI_ROM_RESOURCE; i++)
  		printk(KERN_DEBUG "ATP867X: iomap[%d]=0x%llx
  ", i,
  			(unsigned long long)(host->iomap[i]));
  #endif
  
  	/*
  	 * request, iomap BARs and init port addresses accordingly
  	 */
  	for (i = 0; i < host->n_ports; i++) {
  		struct ata_port *ap = host->ports[i];
  		struct ata_ioports *ioaddr = &ap->ioaddr;
  
  		ioaddr->cmd_addr = ATP867X_IO_PORTBASE(ap, i);
  		ioaddr->ctl_addr = ioaddr->altstatus_addr
  				 = ATP867X_IO_ALTSTATUS(ap, i);
  		ioaddr->bmdma_addr = ATP867X_IO_DMABASE(ap, i);
  
  		ata_sff_std_ports(ioaddr);
  		rc = atp867x_set_priv(ap);
  		if (rc)
  			return rc;
  
  #ifdef	ATP867X_DEBUG
  		atp867x_check_ports(ap, i);
  #endif
  		ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx",
  			(unsigned long)ioaddr->cmd_addr,
  			(unsigned long)ioaddr->ctl_addr);
  		ata_port_desc(ap, "bmdma 0x%lx",
  			(unsigned long)ioaddr->bmdma_addr);
  
  		mask |= 1 << i;
  	}
  
  	if (!mask) {

  		dev_err(gdev, "no available native port
  ");

  		return -ENODEV;
  	}
  
  	atp867x_fixup(host);
  
  	rc = pci_set_dma_mask(pdev, ATA_DMA_MASK);
  	if (rc)
  		return rc;
  
  	rc = pci_set_consistent_dma_mask(pdev, ATA_DMA_MASK);
  	return rc;
  }
  
  static int atp867x_init_one(struct pci_dev *pdev,
  	const struct pci_device_id *id)
  {

  	static const struct ata_port_info info_867x = {
  		.flags		= ATA_FLAG_SLAVE_POSS,
  		.pio_mask	= ATA_PIO4,

  		.udma_mask 	= ATA_UDMA6,
  		.port_ops	= &atp867x_ops,
  	};
  
  	struct ata_host *host;
  	const struct ata_port_info *ppi[] = { &info_867x, NULL };
  	int rc;

  	ata_print_version_once(&pdev->dev, DRV_VERSION);

  
  	rc = pcim_enable_device(pdev);
  	if (rc)
  		return rc;
  
  	printk(KERN_INFO "ATP867X: ATP867 ATA UDMA133 controller (rev %02X)",
  		pdev->device);
  
  	host = ata_host_alloc_pinfo(&pdev->dev, ppi, ATP867X_NUM_PORTS);
  	if (!host) {

  		dev_err(&pdev->dev, "failed to allocate ATA host
  ");

  		rc = -ENOMEM;
  		goto err_out;
  	}
  
  	rc = atp867x_ata_pci_sff_init_host(host);
  	if (rc) {

  		dev_err(&pdev->dev, "failed to init host
  ");

  		goto err_out;
  	}
  
  	pci_set_master(pdev);

  	rc = ata_host_activate(host, pdev->irq, ata_bmdma_interrupt,

  				IRQF_SHARED, &atp867x_sht);
  	if (rc)

  		dev_err(&pdev->dev, "failed to activate host
  ");

  
  err_out:
  	return rc;
  }

  #ifdef CONFIG_PM
  static int atp867x_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;
  
  	atp867x_fixup(host);
  
  	ata_host_resume(host);
  	return 0;
  }
  #endif

  static struct pci_device_id atp867x_pci_tbl[] = {
  	{ PCI_VDEVICE(ARTOP, PCI_DEVICE_ID_ARTOP_ATP867A),	0 },
  	{ PCI_VDEVICE(ARTOP, PCI_DEVICE_ID_ARTOP_ATP867B),	0 },
  	{ },
  };
  
  static struct pci_driver atp867x_driver = {
  	.name 		= DRV_NAME,
  	.id_table 	= atp867x_pci_tbl,
  	.probe 		= atp867x_init_one,
  	.remove		= ata_pci_remove_one,

  #ifdef CONFIG_PM
  	.suspend	= ata_pci_device_suspend,
  	.resume		= atp867x_reinit_one,
  #endif

  };
  
  static int __init atp867x_init(void)
  {
  	return pci_register_driver(&atp867x_driver);
  }
  
  static void __exit atp867x_exit(void)
  {
  	pci_unregister_driver(&atp867x_driver);
  }
  
  MODULE_AUTHOR("John(Jung-Ik) Lee, Google Inc.");
  MODULE_DESCRIPTION("low level driver for Artop/Acard 867x ATA controller");
  MODULE_LICENSE("GPL");
  MODULE_DEVICE_TABLE(pci, atp867x_pci_tbl);
  MODULE_VERSION(DRV_VERSION);
  
  module_init(atp867x_init);
  module_exit(atp867x_exit);