v4.19.13 snapshot.
diff --git a/drivers/ata/pata_optidma.c b/drivers/ata/pata_optidma.c
new file mode 100644
index 0000000..bdec7ef
--- /dev/null
+++ b/drivers/ata/pata_optidma.c
@@ -0,0 +1,455 @@
+/*
+ * pata_optidma.c 	- Opti DMA PATA for new ATA layer
+ *			  (C) 2006 Red Hat Inc
+ *
+ *	The Opti DMA controllers are related to the older PIO PCI controllers
+ *	and indeed the VLB ones. The main differences are that the timing
+ *	numbers are now based off PCI clocks not VLB and differ, and that
+ *	MWDMA is supported.
+ *
+ *	This driver should support Viper-N+, FireStar, FireStar Plus.
+ *
+ *	These devices support virtual DMA for read (aka the CS5520). Later
+ *	chips support UDMA33, but only if the rest of the board logic does,
+ *	so you have to get this right. We don't support the virtual DMA
+ *	but we do handle UDMA.
+ *
+ *	Bits that are worth knowing
+ *		Most control registers are shadowed into I/O registers
+ *		0x1F5 bit 0 tells you if the PCI/VLB clock is 33 or 25Mhz
+ *		Virtual DMA registers *move* between rev 0x02 and rev 0x10
+ *		UDMA requires a 66MHz FSB
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/blkdev.h>
+#include <linux/delay.h>
+#include <scsi/scsi_host.h>
+#include <linux/libata.h>
+
+#define DRV_NAME "pata_optidma"
+#define DRV_VERSION "0.3.2"
+
+enum {
+	READ_REG	= 0,	/* index of Read cycle timing register */
+	WRITE_REG 	= 1,	/* index of Write cycle timing register */
+	CNTRL_REG 	= 3,	/* index of Control register */
+	STRAP_REG 	= 5,	/* index of Strap register */
+	MISC_REG 	= 6	/* index of Miscellaneous register */
+};
+
+static int pci_clock;	/* 0 = 33 1 = 25 */
+
+/**
+ *	optidma_pre_reset		-	probe begin
+ *	@link: ATA link
+ *	@deadline: deadline jiffies for the operation
+ *
+ *	Set up cable type and use generic probe init
+ */
+
+static int optidma_pre_reset(struct ata_link *link, unsigned long deadline)
+{
+	struct ata_port *ap = link->ap;
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	static const struct pci_bits optidma_enable_bits = {
+		0x40, 1, 0x08, 0x00
+	};
+
+	if (ap->port_no && !pci_test_config_bits(pdev, &optidma_enable_bits))
+		return -ENOENT;
+
+	return ata_sff_prereset(link, deadline);
+}
+
+/**
+ *	optidma_unlock		-	unlock control registers
+ *	@ap: ATA port
+ *
+ *	Unlock the control register block for this adapter. Registers must not
+ *	be unlocked in a situation where libata might look at them.
+ */
+
+static void optidma_unlock(struct ata_port *ap)
+{
+	void __iomem *regio = ap->ioaddr.cmd_addr;
+
+	/* These 3 unlock the control register access */
+	ioread16(regio + 1);
+	ioread16(regio + 1);
+	iowrite8(3, regio + 2);
+}
+
+/**
+ *	optidma_lock		-	issue temporary relock
+ *	@ap: ATA port
+ *
+ *	Re-lock the configuration register settings.
+ */
+
+static void optidma_lock(struct ata_port *ap)
+{
+	void __iomem *regio = ap->ioaddr.cmd_addr;
+
+	/* Relock */
+	iowrite8(0x83, regio + 2);
+}
+
+/**
+ *	optidma_mode_setup	-	set mode data
+ *	@ap: ATA interface
+ *	@adev: ATA device
+ *	@mode: Mode to set
+ *
+ *	Called to do the DMA or PIO mode setup. Timing numbers are all
+ *	pre computed to keep the code clean. There are two tables depending
+ *	on the hardware clock speed.
+ *
+ *	WARNING: While we do this the IDE registers vanish. If we take an
+ *	IRQ here we depend on the host set locking to avoid catastrophe.
+ */
+
+static void optidma_mode_setup(struct ata_port *ap, struct ata_device *adev, u8 mode)
+{
+	struct ata_device *pair = ata_dev_pair(adev);
+	int pio = adev->pio_mode - XFER_PIO_0;
+	int dma = adev->dma_mode - XFER_MW_DMA_0;
+	void __iomem *regio = ap->ioaddr.cmd_addr;
+	u8 addr;
+
+	/* Address table precomputed with a DCLK of 2 */
+	static const u8 addr_timing[2][5] = {
+		{ 0x30, 0x20, 0x20, 0x10, 0x10 },
+		{ 0x20, 0x20, 0x10, 0x10, 0x10 }
+	};
+	static const u8 data_rec_timing[2][5] = {
+		{ 0x59, 0x46, 0x30, 0x20, 0x20 },
+		{ 0x46, 0x32, 0x20, 0x20, 0x10 }
+	};
+	static const u8 dma_data_rec_timing[2][3] = {
+		{ 0x76, 0x20, 0x20 },
+		{ 0x54, 0x20, 0x10 }
+	};
+
+	/* Switch from IDE to control mode */
+	optidma_unlock(ap);
+
+
+	/*
+ 	 *	As with many controllers the address setup time is shared
+ 	 *	and must suit both devices if present. FIXME: Check if we
+ 	 *	need to look at slowest of PIO/DMA mode of either device
+	 */
+
+	if (mode >= XFER_MW_DMA_0)
+		addr = 0;
+	else
+		addr = addr_timing[pci_clock][pio];
+
+	if (pair) {
+		u8 pair_addr;
+		/* Hardware constraint */
+		if (pair->dma_mode)
+			pair_addr = 0;
+		else
+			pair_addr = addr_timing[pci_clock][pair->pio_mode - XFER_PIO_0];
+		if (pair_addr > addr)
+			addr = pair_addr;
+	}
+
+	/* Commence primary programming sequence */
+	/* First we load the device number into the timing select */
+	iowrite8(adev->devno, regio + MISC_REG);
+	/* Now we load the data timings into read data/write data */
+	if (mode < XFER_MW_DMA_0) {
+		iowrite8(data_rec_timing[pci_clock][pio], regio + READ_REG);
+		iowrite8(data_rec_timing[pci_clock][pio], regio + WRITE_REG);
+	} else if (mode < XFER_UDMA_0) {
+		iowrite8(dma_data_rec_timing[pci_clock][dma], regio + READ_REG);
+		iowrite8(dma_data_rec_timing[pci_clock][dma], regio + WRITE_REG);
+	}
+	/* Finally we load the address setup into the misc register */
+	iowrite8(addr | adev->devno, regio + MISC_REG);
+
+	/* Programming sequence complete, timing 0 dev 0, timing 1 dev 1 */
+	iowrite8(0x85, regio + CNTRL_REG);
+
+	/* Switch back to IDE mode */
+	optidma_lock(ap);
+
+	/* Note: at this point our programming is incomplete. We are
+	   not supposed to program PCI 0x43 "things we hacked onto the chip"
+	   until we've done both sets of PIO/DMA timings */
+}
+
+/**
+ *	optiplus_mode_setup	-	DMA setup for Firestar Plus
+ *	@ap: ATA port
+ *	@adev: device
+ *	@mode: desired mode
+ *
+ *	The Firestar plus has additional UDMA functionality for UDMA0-2 and
+ *	requires we do some additional work. Because the base work we must do
+ *	is mostly shared we wrap the Firestar setup functionality in this
+ *	one
+ */
+
+static void optiplus_mode_setup(struct ata_port *ap, struct ata_device *adev, u8 mode)
+{
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	u8 udcfg;
+	u8 udslave;
+	int dev2 = 2 * adev->devno;
+	int unit = 2 * ap->port_no + adev->devno;
+	int udma = mode - XFER_UDMA_0;
+
+	pci_read_config_byte(pdev, 0x44, &udcfg);
+	if (mode <= XFER_UDMA_0) {
+		udcfg &= ~(1 << unit);
+		optidma_mode_setup(ap, adev, adev->dma_mode);
+	} else {
+		udcfg |=  (1 << unit);
+		if (ap->port_no) {
+			pci_read_config_byte(pdev, 0x45, &udslave);
+			udslave &= ~(0x03 << dev2);
+			udslave |= (udma << dev2);
+			pci_write_config_byte(pdev, 0x45, udslave);
+		} else {
+			udcfg &= ~(0x30 << dev2);
+			udcfg |= (udma << dev2);
+		}
+	}
+	pci_write_config_byte(pdev, 0x44, udcfg);
+}
+
+/**
+ *	optidma_set_pio_mode	-	PIO setup callback
+ *	@ap: ATA port
+ *	@adev: Device
+ *
+ *	The libata core provides separate functions for handling PIO and
+ *	DMA programming. The architecture of the Firestar makes it easier
+ *	for us to have a common function so we provide wrappers
+ */
+
+static void optidma_set_pio_mode(struct ata_port *ap, struct ata_device *adev)
+{
+	optidma_mode_setup(ap, adev, adev->pio_mode);
+}
+
+/**
+ *	optidma_set_dma_mode	-	DMA setup callback
+ *	@ap: ATA port
+ *	@adev: Device
+ *
+ *	The libata core provides separate functions for handling PIO and
+ *	DMA programming. The architecture of the Firestar makes it easier
+ *	for us to have a common function so we provide wrappers
+ */
+
+static void optidma_set_dma_mode(struct ata_port *ap, struct ata_device *adev)
+{
+	optidma_mode_setup(ap, adev, adev->dma_mode);
+}
+
+/**
+ *	optiplus_set_pio_mode	-	PIO setup callback
+ *	@ap: ATA port
+ *	@adev: Device
+ *
+ *	The libata core provides separate functions for handling PIO and
+ *	DMA programming. The architecture of the Firestar makes it easier
+ *	for us to have a common function so we provide wrappers
+ */
+
+static void optiplus_set_pio_mode(struct ata_port *ap, struct ata_device *adev)
+{
+	optiplus_mode_setup(ap, adev, adev->pio_mode);
+}
+
+/**
+ *	optiplus_set_dma_mode	-	DMA setup callback
+ *	@ap: ATA port
+ *	@adev: Device
+ *
+ *	The libata core provides separate functions for handling PIO and
+ *	DMA programming. The architecture of the Firestar makes it easier
+ *	for us to have a common function so we provide wrappers
+ */
+
+static void optiplus_set_dma_mode(struct ata_port *ap, struct ata_device *adev)
+{
+	optiplus_mode_setup(ap, adev, adev->dma_mode);
+}
+
+/**
+ *	optidma_make_bits	-	PCI setup helper
+ *	@adev: ATA device
+ *
+ *	Turn the ATA device setup into PCI configuration bits
+ *	for register 0x43 and return the two bits needed.
+ */
+
+static u8 optidma_make_bits43(struct ata_device *adev)
+{
+	static const u8 bits43[5] = {
+		0, 0, 0, 1, 2
+	};
+	if (!ata_dev_enabled(adev))
+		return 0;
+	if (adev->dma_mode)
+		return adev->dma_mode - XFER_MW_DMA_0;
+	return bits43[adev->pio_mode - XFER_PIO_0];
+}
+
+/**
+ *	optidma_set_mode	-	mode setup
+ *	@link: link to set up
+ *
+ *	Use the standard setup to tune the chipset and then finalise the
+ *	configuration by writing the nibble of extra bits of data into
+ *	the chip.
+ */
+
+static int optidma_set_mode(struct ata_link *link, struct ata_device **r_failed)
+{
+	struct ata_port *ap = link->ap;
+	u8 r;
+	int nybble = 4 * ap->port_no;
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	int rc  = ata_do_set_mode(link, r_failed);
+	if (rc == 0) {
+		pci_read_config_byte(pdev, 0x43, &r);
+
+		r &= (0x0F << nybble);
+		r |= (optidma_make_bits43(&link->device[0]) +
+		     (optidma_make_bits43(&link->device[0]) << 2)) << nybble;
+		pci_write_config_byte(pdev, 0x43, r);
+	}
+	return rc;
+}
+
+static struct scsi_host_template optidma_sht = {
+	ATA_BMDMA_SHT(DRV_NAME),
+};
+
+static struct ata_port_operations optidma_port_ops = {
+	.inherits	= &ata_bmdma_port_ops,
+	.cable_detect	= ata_cable_40wire,
+	.set_piomode	= optidma_set_pio_mode,
+	.set_dmamode	= optidma_set_dma_mode,
+	.set_mode	= optidma_set_mode,
+	.prereset	= optidma_pre_reset,
+};
+
+static struct ata_port_operations optiplus_port_ops = {
+	.inherits	= &optidma_port_ops,
+	.set_piomode	= optiplus_set_pio_mode,
+	.set_dmamode	= optiplus_set_dma_mode,
+};
+
+/**
+ *	optiplus_with_udma	-	Look for UDMA capable setup
+ *	@pdev; ATA controller
+ */
+
+static int optiplus_with_udma(struct pci_dev *pdev)
+{
+	u8 r;
+	int ret = 0;
+	int ioport = 0x22;
+	struct pci_dev *dev1;
+
+	/* Find function 1 */
+	dev1 = pci_get_device(0x1045, 0xC701, NULL);
+	if (dev1 == NULL)
+		return 0;
+
+	/* Rev must be >= 0x10 */
+	pci_read_config_byte(dev1, 0x08, &r);
+	if (r < 0x10)
+		goto done_nomsg;
+	/* Read the chipset system configuration to check our mode */
+	pci_read_config_byte(dev1, 0x5F, &r);
+	ioport |= (r << 8);
+	outb(0x10, ioport);
+	/* Must be 66Mhz sync */
+	if ((inb(ioport + 2) & 1) == 0)
+		goto done;
+
+	/* Check the ATA arbitration/timing is suitable */
+	pci_read_config_byte(pdev, 0x42, &r);
+	if ((r & 0x36) != 0x36)
+		goto done;
+	pci_read_config_byte(dev1, 0x52, &r);
+	if (r & 0x80)	/* IDEDIR disabled */
+		ret = 1;
+done:
+	printk(KERN_WARNING "UDMA not supported in this configuration.\n");
+done_nomsg:		/* Wrong chip revision */
+	pci_dev_put(dev1);
+	return ret;
+}
+
+static int optidma_init_one(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	static const struct ata_port_info info_82c700 = {
+		.flags = ATA_FLAG_SLAVE_POSS,
+		.pio_mask = ATA_PIO4,
+		.mwdma_mask = ATA_MWDMA2,
+		.port_ops = &optidma_port_ops
+	};
+	static const struct ata_port_info info_82c700_udma = {
+		.flags = ATA_FLAG_SLAVE_POSS,
+		.pio_mask = ATA_PIO4,
+		.mwdma_mask = ATA_MWDMA2,
+		.udma_mask = ATA_UDMA2,
+		.port_ops = &optiplus_port_ops
+	};
+	const struct ata_port_info *ppi[] = { &info_82c700, NULL };
+	int rc;
+
+	ata_print_version_once(&dev->dev, DRV_VERSION);
+
+	rc = pcim_enable_device(dev);
+	if (rc)
+		return rc;
+
+	/* Fixed location chipset magic */
+	inw(0x1F1);
+	inw(0x1F1);
+	pci_clock = inb(0x1F5) & 1;		/* 0 = 33Mhz, 1 = 25Mhz */
+
+	if (optiplus_with_udma(dev))
+		ppi[0] = &info_82c700_udma;
+
+	return ata_pci_bmdma_init_one(dev, ppi, &optidma_sht, NULL, 0);
+}
+
+static const struct pci_device_id optidma[] = {
+	{ PCI_VDEVICE(OPTI, 0xD568), },		/* Opti 82C700 */
+
+	{ },
+};
+
+static struct pci_driver optidma_pci_driver = {
+	.name 		= DRV_NAME,
+	.id_table	= optidma,
+	.probe 		= optidma_init_one,
+	.remove		= ata_pci_remove_one,
+#ifdef CONFIG_PM_SLEEP
+	.suspend	= ata_pci_device_suspend,
+	.resume		= ata_pci_device_resume,
+#endif
+};
+
+module_pci_driver(optidma_pci_driver);
+
+MODULE_AUTHOR("Alan Cox");
+MODULE_DESCRIPTION("low-level driver for Opti Firestar/Firestar Plus");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(pci, optidma);
+MODULE_VERSION(DRV_VERSION);