text: /*
   * Copyright (C) 2000-2002		Mark Lord <mlord@pobox.com>
   * Copyright (C)      2007		Bartlomiej Zolnierkiewicz
   *
   * May be copied or modified under the terms of the GNU General Public License
   *
   * Development of this chipset driver was funded
   * by the nice folks at National Semiconductor.
   *
   * Documentation:
   *	Available from National Semiconductor
   */
  
  #include <linux/module.h>
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/slab.h>
  #include <linux/pci.h>
  #include <linux/init.h>
  #include <linux/ide.h>
  #include <linux/pm.h>
  
  #include <asm/io.h>
  
  #define DRV_NAME "sc1200"
  
  #define SC1200_REV_A	0x00
  #define SC1200_REV_B1	0x01
  #define SC1200_REV_B3	0x02
  #define SC1200_REV_C1	0x03
  #define SC1200_REV_D1	0x04
  
  #define PCI_CLK_33	0x00
  #define PCI_CLK_48	0x01
  #define PCI_CLK_66	0x02
  #define PCI_CLK_33A	0x03
  
  static unsigned short sc1200_get_pci_clock (void)
  {
  	unsigned char chip_id, silicon_revision;
  	unsigned int pci_clock;
  	/*
  	 * Check the silicon revision, as not all versions of the chip
  	 * have the register with the fast PCI bus timings.
  	 */
  	chip_id = inb (0x903c);
  	silicon_revision = inb (0x903d);
  
  	// Read the fast pci clock frequency
  	if (chip_id == 0x04 && silicon_revision < SC1200_REV_B1) {
  		pci_clock = PCI_CLK_33;
  	} else {
  		// check clock generator configuration (cfcc)
  		// the clock is in bits 8 and 9 of this word
  
  		pci_clock = inw (0x901e);
  		pci_clock >>= 8;
  		pci_clock &= 0x03;
  		if (pci_clock == PCI_CLK_33A)
  			pci_clock = PCI_CLK_33;
  	}
  	return pci_clock;
  }
  
  /*
   * Here are the standard PIO mode 0-4 timings for each "format".
   * Format-0 uses fast data reg timings, with slower command reg timings.
   * Format-1 uses fast timings for all registers, but won't work with all drives.
   */
  static const unsigned int sc1200_pio_timings[4][5] =
  	{{0x00009172, 0x00012171, 0x00020080, 0x00032010, 0x00040010},	// format0  33Mhz
  	 {0xd1329172, 0x71212171, 0x30200080, 0x20102010, 0x00100010},	// format1, 33Mhz
  	 {0xfaa3f4f3, 0xc23232b2, 0x513101c1, 0x31213121, 0x10211021},	// format1, 48Mhz
  	 {0xfff4fff4, 0xf35353d3, 0x814102f1, 0x42314231, 0x11311131}};	// format1, 66Mhz
  
  /*
   * After chip reset, the PIO timings are set to 0x00009172, which is not valid.
   */
  //#define SC1200_BAD_PIO(timings) (((timings)&~0x80000000)==0x00009172)
  
  static void sc1200_tunepio(ide_drive_t *drive, u8 pio)
  {
  	ide_hwif_t *hwif = drive->hwif;
  	struct pci_dev *pdev = to_pci_dev(hwif->dev);
  	unsigned int basereg = hwif->channel ? 0x50 : 0x40, format = 0;
  
  	pci_read_config_dword(pdev, basereg + 4, &format);
  	format = (format >> 31) & 1;
  	if (format)
  		format += sc1200_get_pci_clock();
  	pci_write_config_dword(pdev, basereg + ((drive->dn & 1) << 3),
  			       sc1200_pio_timings[format][pio]);
  }
  
  /*
   *	The SC1200 specifies that two drives sharing a cable cannot mix
   *	UDMA/MDMA.  It has to be one or the other, for the pair, though
   *	different timings can still be chosen for each drive.  We could
   *	set the appropriate timing bits on the fly, but that might be
   *	a bit confusing.  So, for now we statically handle this requirement
   *	by looking at our mate drive to see what it is capable of, before
   *	choosing a mode for our own drive.
   */
  static u8 sc1200_udma_filter(ide_drive_t *drive)
  {
  	ide_hwif_t *hwif = drive->hwif;
  	ide_drive_t *mate = ide_get_pair_dev(drive);
  	u16 *mateid;
  	u8 mask = hwif->ultra_mask;
  
  	if (mate == NULL)
  		goto out;
  	mateid = mate->id;
  
  	if (ata_id_has_dma(mateid) && __ide_dma_bad_drive(mate) == 0) {
  		if ((mateid[ATA_ID_FIELD_VALID] & 4) &&
  		    (mateid[ATA_ID_UDMA_MODES] & 7))
  			goto out;
  		if (mateid[ATA_ID_MWDMA_MODES] & 7)
  			mask = 0;
  	}
  out:
  	return mask;
  }
  
  static void sc1200_set_dma_mode(ide_hwif_t *hwif, ide_drive_t *drive)
  {
  	struct pci_dev		*dev = to_pci_dev(hwif->dev);
  	unsigned int		reg, timings;
  	unsigned short		pci_clock;
  	unsigned int		basereg = hwif->channel ? 0x50 : 0x40;
  	const u8		mode = drive->dma_mode;
  
  	static const u32 udma_timing[3][3] = {
  		{ 0x00921250, 0x00911140, 0x00911030 },
  		{ 0x00932470, 0x00922260, 0x00922140 },
  		{ 0x009436a1, 0x00933481, 0x00923261 },
  	};
  
  	static const u32 mwdma_timing[3][3] = {
  		{ 0x00077771, 0x00012121, 0x00002020 },
  		{ 0x000bbbb2, 0x00024241, 0x00013131 },
  		{ 0x000ffff3, 0x00035352, 0x00015151 },
  	};
  
  	pci_clock = sc1200_get_pci_clock();
  
  	/*
  	 * Note that each DMA mode has several timings associated with it.
  	 * The correct timing depends on the fast PCI clock freq.
  	 */
  
  	if (mode >= XFER_UDMA_0)
  		timings =  udma_timing[pci_clock][mode - XFER_UDMA_0];
  	else
  		timings = mwdma_timing[pci_clock][mode - XFER_MW_DMA_0];
  
  	if ((drive->dn & 1) == 0) {
  		pci_read_config_dword(dev, basereg + 4, &reg);
  		timings |= reg & 0x80000000;	/* preserve PIO format bit */
  		pci_write_config_dword(dev, basereg + 4, timings);
  	} else
  		pci_write_config_dword(dev, basereg + 12, timings);
  }
  
  /*  Replacement for the standard ide_dma_end action in
   *  dma_proc.
   *
   *  returns 1 on error, 0 otherwise
   */
  static int sc1200_dma_end(ide_drive_t *drive)
  {
  	ide_hwif_t *hwif = drive->hwif;
  	unsigned long dma_base = hwif->dma_base;
  	u8 dma_stat;
  
  	dma_stat = inb(dma_base+2);		/* get DMA status */
  
  	if (!(dma_stat & 4))
  		printk(" ide_dma_end dma_stat=%0x err=%x newerr=%x\n",
  		  dma_stat, ((dma_stat&7)!=4), ((dma_stat&2)==2));
  
  	outb(dma_stat|0x1b, dma_base+2);	/* clear the INTR & ERROR bits */
  	outb(inb(dma_base)&~1, dma_base);	/* !! DO THIS HERE !! stop DMA */
  
  	return (dma_stat & 7) != 4;		/* verify good DMA status */
  }
  
  /*
   * sc1200_set_pio_mode() handles setting of PIO modes
   * for both the chipset and drive.
   *
   * All existing BIOSs for this chipset guarantee that all drives
   * will have valid default PIO timings set up before we get here.
   */
  
  static void sc1200_set_pio_mode(ide_hwif_t *hwif, ide_drive_t *drive)
  {
  	int		mode = -1;
  	const u8	pio = drive->pio_mode - XFER_PIO_0;
  
  	/*
  	 * bad abuse of ->set_pio_mode interface
  	 */
  	switch (pio) {
  		case 200: mode = XFER_UDMA_0;	break;
  		case 201: mode = XFER_UDMA_1;	break;
  		case 202: mode = XFER_UDMA_2;	break;
  		case 100: mode = XFER_MW_DMA_0;	break;
  		case 101: mode = XFER_MW_DMA_1;	break;
  		case 102: mode = XFER_MW_DMA_2;	break;
  	}
  	if (mode != -1) {
  		printk("SC1200: %s: changing (U)DMA mode\n", drive->name);
  		ide_dma_off_quietly(drive);
  		if (ide_set_dma_mode(drive, mode) == 0 &&
  		    (drive->dev_flags & IDE_DFLAG_USING_DMA))
  			hwif->dma_ops->dma_host_set(drive, 1);
  		return;
  	}
  
  	sc1200_tunepio(drive, pio);
  }
  
  #ifdef CONFIG_PM
  struct sc1200_saved_state {
  	u32 regs[8];
  };
  
  static int sc1200_suspend (struct pci_dev *dev, pm_message_t state)
  {
  	printk("SC1200: suspend(%u)\n", state.event);
  
  	/*
  	 * we only save state when going from full power to less
  	 */
  	if (state.event == PM_EVENT_ON) {
  		struct ide_host *host = pci_get_drvdata(dev);
  		struct sc1200_saved_state *ss = host->host_priv;
  		unsigned int r;
  
  		/*
  		 * save timing registers
  		 * (this may be unnecessary if BIOS also does it)
  		 */
  		for (r = 0; r < 8; r++)
  			pci_read_config_dword(dev, 0x40 + r * 4, &ss->regs[r]);
  	}
  
  	pci_disable_device(dev);
  	pci_set_power_state(dev, pci_choose_state(dev, state));
  	return 0;
  }
  
  static int sc1200_resume (struct pci_dev *dev)
  {
  	struct ide_host *host = pci_get_drvdata(dev);
  	struct sc1200_saved_state *ss = host->host_priv;
  	unsigned int r;
  	int i;
  
  	i = pci_enable_device(dev);
  	if (i)
  		return i;
  
  	/*
  	 * restore timing registers
  	 * (this may be unnecessary if BIOS also does it)
  	 */
  	for (r = 0; r < 8; r++)
  		pci_write_config_dword(dev, 0x40 + r * 4, ss->regs[r]);
  
  	return 0;
  }
  #endif
  
  static const struct ide_port_ops sc1200_port_ops = {
  	.set_pio_mode		= sc1200_set_pio_mode,
  	.set_dma_mode		= sc1200_set_dma_mode,
  	.udma_filter		= sc1200_udma_filter,
  };
  
  static const struct ide_dma_ops sc1200_dma_ops = {
  	.dma_host_set		= ide_dma_host_set,
  	.dma_setup		= ide_dma_setup,
  	.dma_start		= ide_dma_start,
  	.dma_end		= sc1200_dma_end,
  	.dma_test_irq		= ide_dma_test_irq,
  	.dma_lost_irq		= ide_dma_lost_irq,
  	.dma_timer_expiry	= ide_dma_sff_timer_expiry,
  	.dma_sff_read_status	= ide_dma_sff_read_status,
  };
  
  static const struct ide_port_info sc1200_chipset __devinitdata = {
  	.name		= DRV_NAME,
  	.port_ops	= &sc1200_port_ops,
  	.dma_ops	= &sc1200_dma_ops,
  	.host_flags	= IDE_HFLAG_SERIALIZE |
  			  IDE_HFLAG_POST_SET_MODE |
  			  IDE_HFLAG_ABUSE_DMA_MODES,
  	.pio_mask	= ATA_PIO4,
  	.mwdma_mask	= ATA_MWDMA2,
  	.udma_mask	= ATA_UDMA2,
  };
  
  static int __devinit sc1200_init_one(struct pci_dev *dev, const struct pci_device_id *id)
  {
  	struct sc1200_saved_state *ss = NULL;
  	int rc;
  
  #ifdef CONFIG_PM
  	ss = kmalloc(sizeof(*ss), GFP_KERNEL);
  	if (ss == NULL)
  		return -ENOMEM;
  #endif
  	rc = ide_pci_init_one(dev, &sc1200_chipset, ss);
  	if (rc)
  		kfree(ss);
  
  	return rc;
  }
  
  static const struct pci_device_id sc1200_pci_tbl[] = {
  	{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_IDE), 0},
  	{ 0, },
  };
  MODULE_DEVICE_TABLE(pci, sc1200_pci_tbl);
  
  static struct pci_driver sc1200_pci_driver = {
  	.name		= "SC1200_IDE",
  	.id_table	= sc1200_pci_tbl,
  	.probe		= sc1200_init_one,
  	.remove		= ide_pci_remove,
  #ifdef CONFIG_PM
  	.suspend	= sc1200_suspend,
  	.resume		= sc1200_resume,
  #endif
  };
  
  static int __init sc1200_ide_init(void)
  {
  	return ide_pci_register_driver(&sc1200_pci_driver);
  }
  
  static void __exit sc1200_ide_exit(void)
  {
  	pci_unregister_driver(&sc1200_pci_driver);
  }
  
  module_init(sc1200_ide_init);
  module_exit(sc1200_ide_exit);
  
  MODULE_AUTHOR("Mark Lord");
  MODULE_DESCRIPTION("PCI driver module for NS SC1200 IDE");
  MODULE_LICENSE("GPL");
  