[libata] Add a bunch of PATA drivers.

The vast majority of drivers and changes are from Alan Cox.  Albert Lee
contributed and maintains pata_pdc2027x.  Adrian Bunk, Andrew Morton,
and Tejun Heo contributed various minor fixes and updates.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/pata_sl82c105.c b/drivers/ata/pata_sl82c105.c
new file mode 100644
index 0000000..47b290b
--- /dev/null
+++ b/drivers/ata/pata_sl82c105.c
@@ -0,0 +1,388 @@
+/*
+ * pata_sl82c105.c 	- SL82C105 PATA for new ATA layer
+ *			  (C) 2005 Red Hat Inc
+ *			  Alan Cox <alan@redhat.com>
+ *
+ * Based in part on linux/drivers/ide/pci/sl82c105.c
+ * 		SL82C105/Winbond 553 IDE driver
+ *
+ * and in part on the documentation and errata sheet
+ */
+ 
+#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_sl82c105"
+#define DRV_VERSION "0.2.2"
+
+enum {
+	/*
+	 * SL82C105 PCI config register 0x40 bits.
+	 */
+	CTRL_IDE_IRQB	=	(1 << 30),
+	CTRL_IDE_IRQA   =	(1 << 28),
+	CTRL_LEGIRQ     =	(1 << 11),
+	CTRL_P1F16      =	(1 << 5),
+	CTRL_P1EN       =	(1 << 4),
+	CTRL_P0F16      =	(1 << 1),
+	CTRL_P0EN       =	(1 << 0)
+};
+
+/**
+ *	sl82c105_pre_reset		-	probe begin
+ *	@ap: ATA port
+ *
+ *	Set up cable type and use generic probe init
+ */
+ 
+static int sl82c105_pre_reset(struct ata_port *ap)
+{
+	static const struct pci_bits sl82c105_enable_bits[] = {
+		{ 0x40, 1, 0x01, 0x01 },
+		{ 0x40, 1, 0x10, 0x10 }
+	};
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+
+	if (ap->port_no && !pci_test_config_bits(pdev, &sl82c105_enable_bits[ap->port_no])) {
+		ata_port_disable(ap);
+		dev_printk(KERN_INFO, &pdev->dev, "port disabled. ignoring.\n");
+		return 0;
+	}
+	ap->cbl = ATA_CBL_PATA40;
+	return ata_std_prereset(ap);
+}
+
+
+static void sl82c105_error_handler(struct ata_port *ap)
+{
+	ata_bmdma_drive_eh(ap, sl82c105_pre_reset, ata_std_softreset, NULL, ata_std_postreset);
+}
+
+
+/**
+ *	sl82c105_configure_piomode	-	set chip PIO timing
+ *	@ap: ATA interface
+ *	@adev: ATA device
+ *	@pio: PIO mode
+ *
+ *	Called to do the PIO mode setup. Our timing registers are shared
+ *	so a configure_dmamode call will undo any work we do here and vice
+ *	versa
+ */
+ 
+static void sl82c105_configure_piomode(struct ata_port *ap, struct ata_device *adev, int pio)
+{
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	static u16 pio_timing[5] = {
+		0x50D, 0x407, 0x304, 0x242, 0x240
+	};
+	u16 dummy;
+	int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);
+	
+	pci_write_config_word(pdev, timing, pio_timing[pio]);
+	/* Can we lose this oddity of the old driver */
+	pci_read_config_word(pdev, timing, &dummy);
+}
+
+/**
+ *	sl82c105_set_piomode	-	set initial PIO mode data
+ *	@ap: ATA interface
+ *	@adev: ATA device
+ *
+ *	Called to do the PIO mode setup. Our timing registers are shared
+ *	but we want to set the PIO timing by default.
+ */
+ 
+static void sl82c105_set_piomode(struct ata_port *ap, struct ata_device *adev)
+{
+	sl82c105_configure_piomode(ap, adev, adev->pio_mode - XFER_PIO_0);
+}
+
+/**
+ *	sl82c105_configure_dmamode	-	set DMA mode in chip
+ *	@ap: ATA interface
+ *	@adev: ATA device
+ *
+ *	Load DMA cycle times into the chip ready for a DMA transfer
+ *	to occur.
+ */
+ 
+static void sl82c105_configure_dmamode(struct ata_port *ap, struct ata_device *adev)
+{
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	static u16 dma_timing[3] = {
+		0x707, 0x201, 0x200
+	};
+	u16 dummy;
+	int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);
+	int dma = adev->dma_mode - XFER_MW_DMA_0;
+	
+	pci_write_config_word(pdev, timing, dma_timing[dma]);
+	/* Can we lose this oddity of the old driver */
+	pci_read_config_word(pdev, timing, &dummy);
+}
+
+/**
+ *	sl82c105_set_dmamode	-	set initial DMA mode data
+ *	@ap: ATA interface
+ *	@adev: ATA device
+ *
+ *	Called to do the DMA mode setup. This replaces the PIO timings
+ *	for the device in question. Set appropriate PIO timings not DMA
+ *	timings at this point.
+ */
+ 
+static void sl82c105_set_dmamode(struct ata_port *ap, struct ata_device *adev)
+{
+	switch(adev->dma_mode) {
+		case XFER_MW_DMA_0:
+			sl82c105_configure_piomode(ap, adev, 1);
+			break;
+		case XFER_MW_DMA_1:
+			sl82c105_configure_piomode(ap, adev, 3);
+			break;
+		case XFER_MW_DMA_2:
+			sl82c105_configure_piomode(ap, adev, 3);
+			break;
+		default:
+			BUG();
+	}			
+}
+
+/**
+ *	sl82c105_reset_engine	-	Reset the DMA engine
+ *	@ap: ATA interface
+ *
+ *	The sl82c105 has some serious problems with the DMA engine
+ *	when transfers don't run as expected or ATAPI is used. The 
+ *	recommended fix is to reset the engine each use using a chip
+ *	test register.
+ */
+ 
+static void sl82c105_reset_engine(struct ata_port *ap)
+{
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	u16 val;
+	
+	pci_read_config_word(pdev, 0x7E, &val);
+	pci_write_config_word(pdev, 0x7E, val | 4);
+	pci_write_config_word(pdev, 0x7E, val & ~4);
+}
+
+/**
+ *	sl82c105_bmdma_start		-	DMA engine begin
+ *	@qc: ATA command
+ *
+ *	Reset the DMA engine each use as recommended by the errata
+ *	document. 
+ *
+ *	FIXME: if we switch clock at BMDMA start/end we might get better
+ *	PIO performance on DMA capable devices.
+ */
+ 
+static void sl82c105_bmdma_start(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+
+	sl82c105_reset_engine(ap);
+	
+	/* Set the clocks for DMA */
+	sl82c105_configure_dmamode(ap, qc->dev);
+	/* Activate DMA */	
+	ata_bmdma_start(qc);
+}
+
+/**
+ *	sl82c105_bmdma_end		-	DMA engine stop
+ *	@qc: ATA command
+ *
+ *	Reset the DMA engine each use as recommended by the errata
+ *	document.
+ *
+ *	This function is also called to turn off DMA when a timeout occurs
+ *	during DMA operation. In both cases we need to reset the engine,
+ *	so no actual eng_timeout handler is required.
+ *
+ *	We assume bmdma_stop is always called if bmdma_start as called. If
+ *	not then we may need to wrap qc_issue.
+ */
+ 
+static void sl82c105_bmdma_stop(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+
+	ata_bmdma_stop(qc);
+	sl82c105_reset_engine(ap);
+	
+	/* This will redo the initial setup of the DMA device to matching
+	   PIO timings */
+	sl82c105_set_dmamode(ap, qc->dev);
+}
+
+static struct scsi_host_template sl82c105_sht = {
+	.module			= THIS_MODULE,
+	.name			= DRV_NAME,
+	.ioctl			= ata_scsi_ioctl,
+	.queuecommand		= ata_scsi_queuecmd,
+	.can_queue		= ATA_DEF_QUEUE,
+	.this_id		= ATA_SHT_THIS_ID,
+	.sg_tablesize		= LIBATA_MAX_PRD,
+	.max_sectors		= ATA_MAX_SECTORS,
+	.cmd_per_lun		= ATA_SHT_CMD_PER_LUN,
+	.emulated		= ATA_SHT_EMULATED,
+	.use_clustering		= ATA_SHT_USE_CLUSTERING,
+	.proc_name		= DRV_NAME,
+	.dma_boundary		= ATA_DMA_BOUNDARY,
+	.slave_configure	= ata_scsi_slave_config,
+	.bios_param		= ata_std_bios_param,
+};
+
+static struct ata_port_operations sl82c105_port_ops = {
+	.port_disable	= ata_port_disable,
+	.set_piomode	= sl82c105_set_piomode,
+	.set_dmamode	= sl82c105_set_dmamode,
+	.mode_filter	= ata_pci_default_filter,
+
+	.tf_load	= ata_tf_load,
+	.tf_read	= ata_tf_read,
+	.check_status 	= ata_check_status,
+	.exec_command	= ata_exec_command,
+	.dev_select 	= ata_std_dev_select,
+
+	.error_handler	= sl82c105_error_handler,
+
+	.bmdma_setup 	= ata_bmdma_setup,
+	.bmdma_start 	= sl82c105_bmdma_start,
+	.bmdma_stop	= sl82c105_bmdma_stop,
+	.bmdma_status 	= ata_bmdma_status,
+
+	.qc_prep 	= ata_qc_prep,
+	.qc_issue	= ata_qc_issue_prot,
+	.eng_timeout	= ata_eng_timeout,
+	.data_xfer	= ata_pio_data_xfer,
+
+	.irq_handler	= ata_interrupt,
+	.irq_clear	= ata_bmdma_irq_clear,
+	
+	.port_start	= ata_port_start,
+	.port_stop	= ata_port_stop,
+	.host_stop	= ata_host_stop
+};	
+
+/**
+ *	sl82c105_bridge_revision	-	find bridge version
+ *	@pdev: PCI device for the ATA function
+ *
+ *	Locates the PCI bridge associated with the ATA function and
+ *	providing it is a Winbond 553 reports the revision. If it cannot
+ *	find a revision or the right device it returns -1
+ */
+ 
+static int sl82c105_bridge_revision(struct pci_dev *pdev)
+{
+	struct pci_dev *bridge;
+	u8 rev;
+
+	/*
+	 * The bridge should be part of the same device, but function 0.
+	 */
+	bridge = pci_get_slot(pdev->bus,
+			       PCI_DEVFN(PCI_SLOT(pdev->devfn), 0));
+	if (!bridge)
+		return -1;
+
+	/*
+	 * Make sure it is a Winbond 553 and is an ISA bridge.
+	 */
+	if (bridge->vendor != PCI_VENDOR_ID_WINBOND ||
+	    bridge->device != PCI_DEVICE_ID_WINBOND_83C553 ||
+	    bridge->class >> 8 != PCI_CLASS_BRIDGE_ISA) {
+	    	pci_dev_put(bridge);
+		return -1;
+	}
+	/*
+	 * We need to find function 0's revision, not function 1
+	 */
+	pci_read_config_byte(bridge, PCI_REVISION_ID, &rev);
+
+	pci_dev_put(bridge);
+	return rev;
+}
+
+	
+static int sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	static struct ata_port_info info_dma = {
+		.sht = &sl82c105_sht,
+		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
+		.pio_mask = 0x1f,
+		.mwdma_mask = 0x07,
+		.port_ops = &sl82c105_port_ops
+	};
+	static struct ata_port_info info_early = {
+		.sht = &sl82c105_sht,
+		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
+		.pio_mask = 0x1f,
+		.port_ops = &sl82c105_port_ops
+	};
+	static struct ata_port_info *port_info[2] = { &info_early, &info_early };
+	u32 val;
+	int rev;
+
+	rev = sl82c105_bridge_revision(dev);
+	
+	if (rev == -1)
+		dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Unable to find bridge, disabling DMA.\n");
+	else if (rev <= 5)
+		dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Early bridge revision, no DMA available.\n");
+	else {
+		port_info[0] = &info_dma;
+		port_info[1] = &info_dma;
+	}
+	
+	pci_read_config_dword(dev, 0x40, &val);
+	val |= CTRL_P0EN | CTRL_P0F16 | CTRL_P1F16;
+	pci_write_config_dword(dev, 0x40, val);
+
+
+	return ata_pci_init_one(dev, port_info, 1); /* For now */
+}
+
+static struct pci_device_id sl82c105[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_82C105), },
+	{ 0, },
+};
+
+static struct pci_driver sl82c105_pci_driver = {
+	.name 		= DRV_NAME,
+	.id_table	= sl82c105,
+	.probe 		= sl82c105_init_one,
+	.remove		= ata_pci_remove_one
+};
+
+static int __init sl82c105_init(void)
+{
+	return pci_register_driver(&sl82c105_pci_driver);
+}
+
+
+static void __exit sl82c105_exit(void)
+{
+	pci_unregister_driver(&sl82c105_pci_driver);
+}
+
+
+MODULE_AUTHOR("Alan Cox");
+MODULE_DESCRIPTION("low-level driver for Sl82c105");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(pci, sl82c105);
+MODULE_VERSION(DRV_VERSION);
+
+module_init(sl82c105_init);
+module_exit(sl82c105_exit);