/*
   * Copyright (C) 2004-2005 Advanced Micro Devices, Inc.
   * Copyright (C)      2007 Bartlomiej Zolnierkiewicz
   *
   * History:
   * 09/20/2005 - Jaya Kumar <jayakumar.ide@gmail.com>
   * - Reworked tuneproc, set_drive, misc mods to prep for mainline
   * - Work was sponsored by CIS (M) Sdn Bhd.
   * Ported to Kernel 2.6.11 on June 26, 2005 by
   *   Wolfgang Zuleger <wolfgang.zuleger@gmx.de>
   *   Alexander Kiausch <alex.kiausch@t-online.de>
   * Originally developed by AMD for 2.4/2.6
   *
   * Development of this chipset driver was funded
   * by the nice folks at National Semiconductor/AMD.
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published by
   * the Free Software Foundation.
   *
   * Documentation:
   *  CS5535 documentation available from AMD
   */
  
  #include <linux/module.h>
  #include <linux/pci.h>
  #include <linux/ide.h>
  
  #define DRV_NAME "cs5535"
  
  #define MSR_ATAC_BASE		0x51300000
  #define ATAC_GLD_MSR_CAP	(MSR_ATAC_BASE+0)
  #define ATAC_GLD_MSR_CONFIG	(MSR_ATAC_BASE+0x01)
  #define ATAC_GLD_MSR_SMI	(MSR_ATAC_BASE+0x02)
  #define ATAC_GLD_MSR_ERROR	(MSR_ATAC_BASE+0x03)
  #define ATAC_GLD_MSR_PM		(MSR_ATAC_BASE+0x04)
  #define ATAC_GLD_MSR_DIAG	(MSR_ATAC_BASE+0x05)
  #define ATAC_IO_BAR		(MSR_ATAC_BASE+0x08)
  #define ATAC_RESET		(MSR_ATAC_BASE+0x10)
  #define ATAC_CH0D0_PIO		(MSR_ATAC_BASE+0x20)
  #define ATAC_CH0D0_DMA		(MSR_ATAC_BASE+0x21)
  #define ATAC_CH0D1_PIO		(MSR_ATAC_BASE+0x22)
  #define ATAC_CH0D1_DMA		(MSR_ATAC_BASE+0x23)
  #define ATAC_PCI_ABRTERR	(MSR_ATAC_BASE+0x24)
  #define ATAC_BM0_CMD_PRIM	0x00
  #define ATAC_BM0_STS_PRIM	0x02
  #define ATAC_BM0_PRD		0x04
  #define CS5535_CABLE_DETECT	0x48
  
  /* Format I PIO settings. We separate out cmd and data for safer timings */
  
  static unsigned int cs5535_pio_cmd_timings[5] =
  { 0xF7F4, 0x53F3, 0x13F1, 0x5131, 0x1131 };
  static unsigned int cs5535_pio_dta_timings[5] =
  { 0xF7F4, 0xF173, 0x8141, 0x5131, 0x1131 };
  
  static unsigned int cs5535_mwdma_timings[3] =
  { 0x7F0FFFF3, 0x7F035352, 0x7f024241 };
  
  static unsigned int cs5535_udma_timings[5] =
  { 0x7F7436A1, 0x7F733481, 0x7F723261, 0x7F713161, 0x7F703061 };
  
  /* Macros to check if the register is the reset value -  reset value is an
     invalid timing and indicates the register has not been set previously */
  
  #define CS5535_BAD_PIO(timings) ( (timings&~0x80000000UL) == 0x00009172 )
  #define CS5535_BAD_DMA(timings) ( (timings & 0x000FFFFF) == 0x00077771 )
  
  /****
   *	cs5535_set_speed         -     Configure the chipset to the new speed
   *	@drive: Drive to set up
   *	@speed: desired speed
   *
   *	cs5535_set_speed() configures the chipset to a new speed.
   */
  static void cs5535_set_speed(ide_drive_t *drive, const u8 speed)
  {
  	u32 reg = 0, dummy;
  	u8 unit = drive->dn & 1;
  
  	/* Set the PIO timings */
  	if (speed < XFER_SW_DMA_0) {
  		ide_drive_t *pair = ide_get_pair_dev(drive);
  		u8 cmd, pioa;
  
  		cmd = pioa = speed - XFER_PIO_0;
  
  		if (pair) {
  			u8 piob = pair->pio_mode - XFER_PIO_0;
  
  			if (piob < cmd)
  				cmd = piob;
  		}
  
  		/* Write the speed of the current drive */
  		reg = (cs5535_pio_cmd_timings[cmd] << 16) |
  			cs5535_pio_dta_timings[pioa];
  		wrmsr(unit ? ATAC_CH0D1_PIO : ATAC_CH0D0_PIO, reg, 0);
  
  		/* And if nessesary - change the speed of the other drive */
  		rdmsr(unit ?  ATAC_CH0D0_PIO : ATAC_CH0D1_PIO, reg, dummy);
  
  		if (((reg >> 16) & cs5535_pio_cmd_timings[cmd]) !=
  			cs5535_pio_cmd_timings[cmd]) {
  			reg &= 0x0000FFFF;
  			reg |= cs5535_pio_cmd_timings[cmd] << 16;
  			wrmsr(unit ? ATAC_CH0D0_PIO : ATAC_CH0D1_PIO, reg, 0);
  		}
  
  		/* Set bit 31 of the DMA register for PIO format 1 timings */
  		rdmsr(unit ?  ATAC_CH0D1_DMA : ATAC_CH0D0_DMA, reg, dummy);
  		wrmsr(unit ? ATAC_CH0D1_DMA : ATAC_CH0D0_DMA,
  					reg | 0x80000000UL, 0);
  	} else {
  		rdmsr(unit ? ATAC_CH0D1_DMA : ATAC_CH0D0_DMA, reg, dummy);
  
  		reg &= 0x80000000UL;  /* Preserve the PIO format bit */
  
  		if (speed >= XFER_UDMA_0 && speed <= XFER_UDMA_4)
  			reg |= cs5535_udma_timings[speed - XFER_UDMA_0];
  		else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2)
  			reg |= cs5535_mwdma_timings[speed - XFER_MW_DMA_0];
  		else
  			return;
  
  		wrmsr(unit ? ATAC_CH0D1_DMA : ATAC_CH0D0_DMA, reg, 0);
  	}
  }
  
  /**
   *	cs5535_set_dma_mode	-	set host controller for DMA mode
   *	@hwif: port
   *	@drive: drive
   *
   *	Programs the chipset for DMA mode.
   */
  
  static void cs5535_set_dma_mode(ide_hwif_t *hwif, ide_drive_t *drive)
  {
  	cs5535_set_speed(drive, drive->dma_mode);
  }
  
  /**
   *	cs5535_set_pio_mode	-	set host controller for PIO mode
   *	@hwif: port
   *	@drive: drive
   *
   *	A callback from the upper layers for PIO-only tuning.
   */
  
  static void cs5535_set_pio_mode(ide_hwif_t *hwif, ide_drive_t *drive)
  {
  	cs5535_set_speed(drive, drive->pio_mode);
  }
  
  static u8 cs5535_cable_detect(ide_hwif_t *hwif)
  {
  	struct pci_dev *dev = to_pci_dev(hwif->dev);
  	u8 bit;
  
  	/* if a 80 wire cable was detected */
  	pci_read_config_byte(dev, CS5535_CABLE_DETECT, &bit);
  
  	return (bit & 1) ? ATA_CBL_PATA80 : ATA_CBL_PATA40;
  }
  
  static const struct ide_port_ops cs5535_port_ops = {
  	.set_pio_mode		= cs5535_set_pio_mode,
  	.set_dma_mode		= cs5535_set_dma_mode,
  	.cable_detect		= cs5535_cable_detect,
  };
  
  static const struct ide_port_info cs5535_chipset = {
  	.name		= DRV_NAME,
  	.port_ops	= &cs5535_port_ops,
  	.host_flags	= IDE_HFLAG_SINGLE | IDE_HFLAG_POST_SET_MODE,
  	.pio_mask	= ATA_PIO4,
  	.mwdma_mask	= ATA_MWDMA2,
  	.udma_mask	= ATA_UDMA4,
  };
  
  static int cs5535_init_one(struct pci_dev *dev, const struct pci_device_id *id)
  {
  	return ide_pci_init_one(dev, &cs5535_chipset, NULL);
  }
  
  static const struct pci_device_id cs5535_pci_tbl[] = {
  	{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_CS5535_IDE), 0 },
  	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_CS5535_IDE), },
  	{ 0, },
  };
  
  MODULE_DEVICE_TABLE(pci, cs5535_pci_tbl);
  
  static struct pci_driver cs5535_pci_driver = {
  	.name		= "CS5535_IDE",
  	.id_table	= cs5535_pci_tbl,
  	.probe		= cs5535_init_one,
  	.remove		= ide_pci_remove,
  	.suspend	= ide_pci_suspend,
  	.resume		= ide_pci_resume,
  };
  
  static int __init cs5535_ide_init(void)
  {
  	return ide_pci_register_driver(&cs5535_pci_driver);
  }
  
  static void __exit cs5535_ide_exit(void)
  {
  	pci_unregister_driver(&cs5535_pci_driver);
  }
  
  module_init(cs5535_ide_init);
  module_exit(cs5535_ide_exit);
  
  MODULE_AUTHOR("AMD");
  MODULE_DESCRIPTION("PCI driver module for AMD/NS CS5535 IDE");
  MODULE_LICENSE("GPL");