v4.19.13 snapshot.
diff --git a/drivers/ata/pata_sc1200.c b/drivers/ata/pata_sc1200.c
new file mode 100644
index 0000000..c71de5d
--- /dev/null
+++ b/drivers/ata/pata_sc1200.c
@@ -0,0 +1,269 @@
+/*
+ * New ATA layer SC1200 driver		Alan Cox <alan@lxorguk.ukuu.org.uk>
+ *
+ * TODO: Mode selection filtering
+ * TODO: Needs custom DMA cleanup code
+ *
+ * Based very heavily on
+ *
+ * linux/drivers/ide/pci/sc1200.c		Version 0.91	28-Jan-2003
+ *
+ * Copyright (C) 2000-2002		Mark Lord <mlord@pobox.com>
+ * 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.
+ *
+ * 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.
+ *
+ * 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
+ *
+ */
+
+#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_sc1200"
+#define DRV_VERSION	"0.2.6"
+
+#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
+
+/**
+ *	sc1200_clock	-	PCI clock
+ *
+ *	Return the PCI bus clocking for the SC1200 chipset configuration
+ *	in use. We return 0 for 33MHz 1 for 48MHz and 2 for 66Mhz
+ */
+
+static int sc1200_clock(void)
+{
+	/* Magic registers that give us the chipset data */
+	u8 chip_id = inb(0x903C);
+	u8 silicon_rev = inb(0x903D);
+	u16 pci_clock;
+
+	if (chip_id == 0x04 && silicon_rev < SC1200_REV_B1)
+		return 0;	/* 33 MHz mode */
+
+	/* Clock generator configuration 0x901E its 8/9 are the PCI clocking
+	   0/3 is 33Mhz 1 is 48 2 is 66 */
+
+	pci_clock = inw(0x901E);
+	pci_clock >>= 8;
+	pci_clock &= 0x03;
+	if (pci_clock == 3)
+		pci_clock = 0;
+	return pci_clock;
+}
+
+/**
+ *	sc1200_set_piomode		-	PIO setup
+ *	@ap: ATA interface
+ *	@adev: device on the interface
+ *
+ *	Set our PIO requirements. This is fairly simple on the SC1200
+ */
+
+static void sc1200_set_piomode(struct ata_port *ap, struct ata_device *adev)
+{
+	static const u32 pio_timings[4][5] = {
+		/* format0, 33Mhz */
+		{ 0x00009172, 0x00012171, 0x00020080, 0x00032010, 0x00040010 },
+		/* format1, 33Mhz */
+		{ 0xd1329172, 0x71212171, 0x30200080, 0x20102010, 0x00100010 },
+		/* format1, 48Mhz */
+		{ 0xfaa3f4f3, 0xc23232b2, 0x513101c1, 0x31213121, 0x10211021 },
+		/* format1, 66Mhz */
+		{ 0xfff4fff4, 0xf35353d3, 0x814102f1, 0x42314231, 0x11311131 }
+	};
+
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	u32 format;
+	unsigned int reg = 0x40 + 0x10 * ap->port_no;
+	int mode = adev->pio_mode - XFER_PIO_0;
+
+	pci_read_config_dword(pdev, reg + 4, &format);
+	format >>= 31;
+	format += sc1200_clock();
+	pci_write_config_dword(pdev, reg + 8 * adev->devno,
+				pio_timings[format][mode]);
+}
+
+/**
+ *	sc1200_set_dmamode		-	DMA timing setup
+ *	@ap: ATA interface
+ *	@adev: Device being configured
+ *
+ *	We cannot mix MWDMA and UDMA without reloading timings each switch
+ *	master to slave.
+ */
+
+static void sc1200_set_dmamode(struct ata_port *ap, struct ata_device *adev)
+{
+	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 }
+	};
+
+	int clock = sc1200_clock();
+	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+	unsigned int reg = 0x40 + 0x10 * ap->port_no;
+	int mode = adev->dma_mode;
+	u32 format;
+
+	if (mode >= XFER_UDMA_0)
+		format = udma_timing[clock][mode - XFER_UDMA_0];
+	else
+		format = mwdma_timing[clock][mode - XFER_MW_DMA_0];
+
+	if (adev->devno == 0) {
+		u32 timings;
+
+		pci_read_config_dword(pdev, reg + 4, &timings);
+		timings &= 0x80000000UL;
+		timings |= format;
+		pci_write_config_dword(pdev, reg + 4, timings);
+	} else
+		pci_write_config_dword(pdev, reg + 12, format);
+}
+
+/**
+ *	sc1200_qc_issue		-	command issue
+ *	@qc: command pending
+ *
+ *	Called when the libata layer is about to issue a command. We wrap
+ *	this interface so that we can load the correct ATA timings if
+ *	necessary.  Specifically we have a problem that there is only
+ *	one MWDMA/UDMA bit.
+ */
+
+static unsigned int sc1200_qc_issue(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	struct ata_device *adev = qc->dev;
+	struct ata_device *prev = ap->private_data;
+
+	/* See if the DMA settings could be wrong */
+	if (ata_dma_enabled(adev) && adev != prev && prev != NULL) {
+		/* Maybe, but do the channels match MWDMA/UDMA ? */
+		if ((ata_using_udma(adev) && !ata_using_udma(prev)) ||
+		    (ata_using_udma(prev) && !ata_using_udma(adev)))
+		    	/* Switch the mode bits */
+		    	sc1200_set_dmamode(ap, adev);
+	}
+
+	return ata_bmdma_qc_issue(qc);
+}
+
+/**
+ *	sc1200_qc_defer	-	implement serialization
+ *	@qc: command
+ *
+ *	Serialize command issue on this controller.
+ */
+
+static int sc1200_qc_defer(struct ata_queued_cmd *qc)
+{
+	struct ata_host *host = qc->ap->host;
+	struct ata_port *alt = host->ports[1 ^ qc->ap->port_no];
+	int rc;
+
+	/* First apply the usual rules */
+	rc = ata_std_qc_defer(qc);
+	if (rc != 0)
+		return rc;
+
+	/* Now apply serialization rules. Only allow a command if the
+	   other channel state machine is idle */
+	if (alt && alt->qc_active)
+		return	ATA_DEFER_PORT;
+	return 0;
+}
+
+static struct scsi_host_template sc1200_sht = {
+	ATA_BMDMA_SHT(DRV_NAME),
+	.sg_tablesize	= LIBATA_DUMB_MAX_PRD,
+};
+
+static struct ata_port_operations sc1200_port_ops = {
+	.inherits	= &ata_bmdma_port_ops,
+	.qc_prep 	= ata_bmdma_dumb_qc_prep,
+	.qc_issue	= sc1200_qc_issue,
+	.qc_defer	= sc1200_qc_defer,
+	.cable_detect	= ata_cable_40wire,
+	.set_piomode	= sc1200_set_piomode,
+	.set_dmamode	= sc1200_set_dmamode,
+};
+
+/**
+ *	sc1200_init_one		-	Initialise an SC1200
+ *	@dev: PCI device
+ *	@id: Entry in match table
+ *
+ *	Just throw the needed data at the libata helper and it does all
+ *	our work.
+ */
+
+static int sc1200_init_one(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	static const struct ata_port_info info = {
+		.flags = ATA_FLAG_SLAVE_POSS,
+		.pio_mask = ATA_PIO4,
+		.mwdma_mask = ATA_MWDMA2,
+		.udma_mask = ATA_UDMA2,
+		.port_ops = &sc1200_port_ops
+	};
+	const struct ata_port_info *ppi[] = { &info, NULL };
+
+	return ata_pci_bmdma_init_one(dev, ppi, &sc1200_sht, NULL, 0);
+}
+
+static const struct pci_device_id sc1200[] = {
+	{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_IDE), },
+
+	{ },
+};
+
+static struct pci_driver sc1200_pci_driver = {
+	.name 		= DRV_NAME,
+	.id_table	= sc1200,
+	.probe 		= sc1200_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(sc1200_pci_driver);
+
+MODULE_AUTHOR("Alan Cox, Mark Lord");
+MODULE_DESCRIPTION("low-level driver for the NS/AMD SC1200");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(pci, sc1200);
+MODULE_VERSION(DRV_VERSION);