1 files changed, 381 insertions, 0 deletions
diff --git a/drivers/ata/pata_sl82c105.c b/drivers/ata/pata_sl82c105.c
new file mode 100644
index 000000000..8487470e2
--- /dev/null
+++ b/drivers/ata/pata_sl82c105.c
@@ -0,0 +1,381 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * pata_sl82c105.c 	- SL82C105 PATA for new ATA layer
+ *			  (C) 2005 Red Hat Inc
+ *			  (C) 2011 Bartlomiej Zolnierkiewicz
+ *
+ * Based in part on linux/drivers/ide/pci/sl82c105.c
+ * 		SL82C105/Winbond 553 IDE driver
+ *
+ * and in part on the documentation and errata sheet
+ *
+ *
+ * Note: The controller like many controllers has shared timings for
+ * PIO and DMA. We thus flip to the DMA timings in dma_start and flip back
+ * in the dma_stop function. Thus we actually don't need a set_dmamode
+ * method as the PIO method is always called and will set the right PIO
+ * timing parameters.
+ */
+
+#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_sl82c105"
+#define DRV_VERSION "0.3.3"
+
+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
+ *	@link: ATA link
+ *	@deadline: deadline jiffies for the operation
+ *
+ *	Set up cable type and use generic probe init
+ */
+
+static int sl82c105_pre_reset(struct ata_link *link, unsigned long deadline)
+{
+	static const struct pci_bits sl82c105_enable_bits[] = {
+		{ 0x40, 1, 0x01, 0x01 },
+		{ 0x40, 1, 0x10, 0x10 }
+	};
+	struct ata_port *ap = link->ap;
+	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]))
+		return -ENOENT;
+	return ata_sff_prereset(link, deadline);
+}
+
+
+/**
+ *	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_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;
+
+	udelay(100);
+	sl82c105_reset_engine(ap);
+	udelay(100);
+
+	/* Set the clocks for DMA */
+	sl82c105_configure_dmamode(ap, qc->dev);
+	/* Activate DMA */
+	ata_bmdma_start(qc);
+}
+
+/**
+ *	sl82c105_bmdma_stop		-	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);
+	udelay(100);
+
+	/* This will redo the initial setup of the DMA device to matching
+	   PIO timings */
+	sl82c105_set_piomode(ap, qc->dev);
+}
+
+/**
+ *	sl82c105_qc_defer	-	implement serialization
+ *	@qc: command
+ *
+ *	We must issue one command per host not per channel because
+ *	of the reset bug.
+ *
+ *	Q: is the scsi host lock sufficient ?
+ */
+
+static int sl82c105_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 bool sl82c105_sff_irq_check(struct ata_port *ap)
+{
+	struct pci_dev *pdev	= to_pci_dev(ap->host->dev);
+	u32 val, mask		= ap->port_no ? CTRL_IDE_IRQB : CTRL_IDE_IRQA;
+
+	pci_read_config_dword(pdev, 0x40, &val);
+
+	return val & mask;
+}
+
+static struct scsi_host_template sl82c105_sht = {
+	ATA_BMDMA_SHT(DRV_NAME),
+};
+
+static struct ata_port_operations sl82c105_port_ops = {
+	.inherits	= &ata_bmdma_port_ops,
+	.qc_defer	= sl82c105_qc_defer,
+	.bmdma_start 	= sl82c105_bmdma_start,
+	.bmdma_stop	= sl82c105_bmdma_stop,
+	.cable_detect	= ata_cable_40wire,
+	.set_piomode	= sl82c105_set_piomode,
+	.prereset	= sl82c105_pre_reset,
+	.sff_irq_check	= sl82c105_sff_irq_check,
+};
+
+/**
+ *	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;
+
+	/*
+	 * 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_dev_put(bridge);
+	return bridge->revision;
+}
+
+static void sl82c105_fixup(struct pci_dev *pdev)
+{
+	u32 val;
+
+	pci_read_config_dword(pdev, 0x40, &val);
+	val |= CTRL_P0EN | CTRL_P0F16 | CTRL_P1F16;
+	pci_write_config_dword(pdev, 0x40, val);
+}
+
+static int sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	static const struct ata_port_info info_dma = {
+		.flags = ATA_FLAG_SLAVE_POSS,
+		.pio_mask = ATA_PIO4,
+		.mwdma_mask = ATA_MWDMA2,
+		.port_ops = &sl82c105_port_ops
+	};
+	static const struct ata_port_info info_early = {
+		.flags = ATA_FLAG_SLAVE_POSS,
+		.pio_mask = ATA_PIO4,
+		.port_ops = &sl82c105_port_ops
+	};
+	/* for now use only the first port */
+	const struct ata_port_info *ppi[] = { &info_early,
+					       NULL };
+	int rev;
+	int rc;
+
+	rc = pcim_enable_device(dev);
+	if (rc)
+		return rc;
+
+	rev = sl82c105_bridge_revision(dev);
+
+	if (rev == -1)
+		dev_warn(&dev->dev,
+			 "pata_sl82c105: Unable to find bridge, disabling DMA\n");
+	else if (rev <= 5)
+		dev_warn(&dev->dev,
+			 "pata_sl82c105: Early bridge revision, no DMA available\n");
+	else
+		ppi[0] = &info_dma;
+
+	sl82c105_fixup(dev);
+
+	return ata_pci_bmdma_init_one(dev, ppi, &sl82c105_sht, NULL, 0);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int sl82c105_reinit_one(struct pci_dev *pdev)
+{
+	struct ata_host *host = pci_get_drvdata(pdev);
+	int rc;
+
+	rc = ata_pci_device_do_resume(pdev);
+	if (rc)
+		return rc;
+
+	sl82c105_fixup(pdev);
+
+	ata_host_resume(host);
+	return 0;
+}
+#endif
+
+static const struct pci_device_id sl82c105[] = {
+	{ PCI_VDEVICE(WINBOND, PCI_DEVICE_ID_WINBOND_82C105), },
+
+	{ },
+};
+
+static struct pci_driver sl82c105_pci_driver = {
+	.name 		= DRV_NAME,
+	.id_table	= sl82c105,
+	.probe 		= sl82c105_init_one,
+	.remove		= ata_pci_remove_one,
+#ifdef CONFIG_PM_SLEEP
+	.suspend	= ata_pci_device_suspend,
+	.resume		= sl82c105_reinit_one,
+#endif
+};
+
+module_pci_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);