Merge pobox.com:/spare/repo/libata-dev/ahci

into pobox.com:/spare/repo/libata-2.6

drivers/scsi/Kconfig

@@ -406,6 +406,14 @@ config SCSI_SATA
 
 	  If unsure, say N.
 
+config SCSI_SATA_AHCI
+	tristate "AHCI SATA support"
+	depends on SCSI_SATA && PCI && EXPERIMENTAL
+	help
+	  This option enables support for AHCI Serial ATA.
+
+	  If unsure, say N.
+
 config SCSI_SATA_SVW
 	tristate "ServerWorks Frodo / Apple K2 SATA support (EXPERIMENTAL)"
 	depends on SCSI_SATA && PCI && EXPERIMENTAL

drivers/scsi/Makefile

@@ -121,6 +121,7 @@ obj-$(CONFIG_SCSI_LASI700)	+= 53c700.o lasi700.o
 obj-$(CONFIG_SCSI_NSP32)	+= nsp32.o
 obj-$(CONFIG_SCSI_IPR)		+= ipr.o
 obj-$(CONFIG_SCSI_IBMVSCSI)	+= ibmvscsi/
+obj-$(CONFIG_SCSI_SATA_AHCI)	+= libata.o ahci.o
 obj-$(CONFIG_SCSI_SATA_SVW)	+= libata.o sata_svw.o
 obj-$(CONFIG_SCSI_ATA_PIIX)	+= libata.o ata_piix.o
 obj-$(CONFIG_SCSI_SATA_PROMISE)	+= libata.o sata_promise.o

drivers/scsi/ahci.c

+/*
+ *  ahci.c - AHCI SATA support
+ *
+ *  Copyright 2004 Red Hat, Inc.
+ *
+ *  The contents of this file are subject to the Open
+ *  Software License version 1.1 that can be found at
+ *  http://www.opensource.org/licenses/osl-1.1.txt and is included herein
+ *  by reference.
+ *
+ *  Alternatively, the contents of this file may be used under the terms
+ *  of the GNU General Public License version 2 (the "GPL") as distributed
+ *  in the kernel source COPYING file, in which case the provisions of
+ *  the GPL are applicable instead of the above.  If you wish to allow
+ *  the use of your version of this file only under the terms of the
+ *  GPL and not to allow others to use your version of this file under
+ *  the OSL, indicate your decision by deleting the provisions above and
+ *  replace them with the notice and other provisions required by the GPL.
+ *  If you do not delete the provisions above, a recipient may use your
+ *  version of this file under either the OSL or the GPL.
+ *
+ * Version 1.0 of the AHCI specification:
+ * http://www.intel.com/technology/serialata/pdf/rev1_0.pdf
+ *
+ */
+
+#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 <linux/interrupt.h>
+#include <linux/sched.h>
+#include "scsi.h"
+#include <scsi/scsi_host.h>
+#include <linux/libata.h>
+#include <asm/io.h>
+
+#define DRV_NAME	"ahci"
+#define DRV_VERSION	"0.11"
+
+
+enum {
+	AHCI_PCI_BAR		= 5,
+	AHCI_MAX_SG		= 168, /* hardware max is 64K */
+	AHCI_DMA_BOUNDARY	= 0xffffffff,
+	AHCI_USE_CLUSTERING	= 0,
+	AHCI_CMD_SLOT_SZ	= 32 * 32,
+	AHCI_RX_FIS_SZ		= 256,
+	AHCI_CMD_TBL_HDR	= 0x80,
+	AHCI_CMD_TBL_SZ		= AHCI_CMD_TBL_HDR + (AHCI_MAX_SG * 16),
+	AHCI_PORT_PRIV_DMA_SZ	= AHCI_CMD_SLOT_SZ + AHCI_CMD_TBL_SZ +
+				  AHCI_RX_FIS_SZ,
+	AHCI_IRQ_ON_SG		= (1 << 31),
+	AHCI_CMD_ATAPI		= (1 << 5),
+	AHCI_CMD_WRITE		= (1 << 6),
+
+	RX_FIS_D2H_REG		= 0x40,	/* offset of D2H Register FIS data */
+
+	board_ahci		= 0,
+
+	/* global controller registers */
+	HOST_CAP		= 0x00, /* host capabilities */
+	HOST_CTL		= 0x04, /* global host control */
+	HOST_IRQ_STAT		= 0x08, /* interrupt status */
+	HOST_PORTS_IMPL		= 0x0c, /* bitmap of implemented ports */
+	HOST_VERSION		= 0x10, /* AHCI spec. version compliancy */
+
+	/* HOST_CTL bits */
+	HOST_RESET		= (1 << 0),  /* reset controller; self-clear */
+	HOST_IRQ_EN		= (1 << 1),  /* global IRQ enable */
+	HOST_AHCI_EN		= (1 << 31), /* AHCI enabled */
+
+	/* HOST_CAP bits */
+	HOST_CAP_64		= (1 << 31), /* PCI DAC (64-bit DMA) support */
+
+	/* registers for each SATA port */
+	PORT_LST_ADDR		= 0x00, /* command list DMA addr */
+	PORT_LST_ADDR_HI	= 0x04, /* command list DMA addr hi */
+	PORT_FIS_ADDR		= 0x08, /* FIS rx buf addr */
+	PORT_FIS_ADDR_HI	= 0x0c, /* FIS rx buf addr hi */
+	PORT_IRQ_STAT		= 0x10, /* interrupt status */
+	PORT_IRQ_MASK		= 0x14, /* interrupt enable/disable mask */
+	PORT_CMD		= 0x18, /* port command */
+	PORT_TFDATA		= 0x20,	/* taskfile data */
+	PORT_SIG		= 0x24,	/* device TF signature */
+	PORT_CMD_ISSUE		= 0x38, /* command issue */
+	PORT_SCR		= 0x28, /* SATA phy register block */
+	PORT_SCR_STAT		= 0x28, /* SATA phy register: SStatus */
+	PORT_SCR_CTL		= 0x2c, /* SATA phy register: SControl */
+	PORT_SCR_ERR		= 0x30, /* SATA phy register: SError */
+
+	/* PORT_IRQ_{STAT,MASK} bits */
+	PORT_IRQ_COLD_PRES	= (1 << 31), /* cold presence detect */
+	PORT_IRQ_TF_ERR		= (1 << 30), /* task file error */
+	PORT_IRQ_HBUS_ERR	= (1 << 29), /* host bus fatal error */
+	PORT_IRQ_HBUS_DATA_ERR	= (1 << 28), /* host bus data error */
+	PORT_IRQ_IF_ERR		= (1 << 27), /* interface fatal error */
+	PORT_IRQ_IF_NONFATAL	= (1 << 26), /* interface non-fatal error */
+	PORT_IRQ_OVERFLOW	= (1 << 24), /* xfer exhausted available S/G */
+	PORT_IRQ_BAD_PMP	= (1 << 23), /* incorrect port multiplier */
+
+	PORT_IRQ_PHYRDY		= (1 << 22), /* PhyRdy changed */
+	PORT_IRQ_DEV_ILCK	= (1 << 7), /* device interlock */
+	PORT_IRQ_CONNECT	= (1 << 6), /* port connect change status */
+	PORT_IRQ_SG_DONE	= (1 << 5), /* descriptor processed */
+	PORT_IRQ_UNK_FIS	= (1 << 4), /* unknown FIS rx'd */
+	PORT_IRQ_SDB_FIS	= (1 << 3), /* Set Device Bits FIS rx'd */
+	PORT_IRQ_DMAS_FIS	= (1 << 2), /* DMA Setup FIS rx'd */
+	PORT_IRQ_PIOS_FIS	= (1 << 1), /* PIO Setup FIS rx'd */
+	PORT_IRQ_D2H_REG_FIS	= (1 << 0), /* D2H Register FIS rx'd */
+
+	PORT_IRQ_FATAL		= PORT_IRQ_TF_ERR |
+				  PORT_IRQ_HBUS_ERR |
+				  PORT_IRQ_HBUS_DATA_ERR |
+				  PORT_IRQ_IF_ERR,
+	DEF_PORT_IRQ		= PORT_IRQ_FATAL | PORT_IRQ_PHYRDY |
+				  PORT_IRQ_D2H_REG_FIS,
+
+	/* PORT_CMD bits */
+	PORT_CMD_LIST_ON	= (1 << 15), /* cmd list DMA engine running */
+	PORT_CMD_FIS_ON		= (1 << 14), /* FIS DMA engine running */
+	PORT_CMD_FIS_RX		= (1 << 4), /* Enable FIS receive DMA engine */
+	PORT_CMD_POWER_ON	= (1 << 2), /* Power up device */
+	PORT_CMD_SPIN_UP	= (1 << 1), /* Spin up device */
+	PORT_CMD_START		= (1 << 0), /* Enable port DMA engine */
+
+	PORT_CMD_ICC_ACTIVE	= (0x1 << 28), /* Put i/f in active state */
+	PORT_CMD_ICC_PARTIAL	= (0x2 << 28), /* Put i/f in partial state */
+	PORT_CMD_ICC_SLUMBER	= (0x6 << 28), /* Put i/f in slumber state */
+};
+
+struct ahci_cmd_hdr {
+	u32			opts;
+	u32			status;
+	u32			tbl_addr;
+	u32			tbl_addr_hi;
+	u32			reserved[4];
+};
+
+struct ahci_sg {
+	u32			addr;
+	u32			addr_hi;
+	u32			reserved;
+	u32			flags_size;
+};
+
+struct ahci_host_priv {
+	unsigned long		flags;
+	u32			cap;	/* cache of HOST_CAP register */
+	u32			port_map; /* cache of HOST_PORTS_IMPL reg */
+};
+
+struct ahci_port_priv {
+	struct ahci_cmd_hdr	*cmd_slot;
+	dma_addr_t		cmd_slot_dma;
+	void			*cmd_tbl;
+	dma_addr_t		cmd_tbl_dma;
+	struct ahci_sg		*cmd_tbl_sg;
+	void			*rx_fis;
+	dma_addr_t		rx_fis_dma;
+};
+
+static u32 ahci_scr_read (struct ata_port *ap, unsigned int sc_reg);
+static void ahci_scr_write (struct ata_port *ap, unsigned int sc_reg, u32 val);
+static int ahci_init_one (struct pci_dev *pdev, const struct pci_device_id *ent);
+static int ahci_qc_issue(struct ata_queued_cmd *qc);
+static irqreturn_t ahci_interrupt (int irq, void *dev_instance, struct pt_regs *regs);
+static void ahci_phy_reset(struct ata_port *ap);
+static void ahci_irq_clear(struct ata_port *ap);
+static void ahci_eng_timeout(struct ata_port *ap);
+static int ahci_port_start(struct ata_port *ap);
+static void ahci_port_stop(struct ata_port *ap);
+static void ahci_host_stop(struct ata_host_set *host_set);
+static void ahci_qc_prep(struct ata_queued_cmd *qc);
+static u8 ahci_check_status(struct ata_port *ap);
+static inline int ahci_host_intr(struct ata_port *ap, struct ata_queued_cmd *qc);
+
+static Scsi_Host_Template ahci_sht = {
+	.module			= THIS_MODULE,
+	.name			= DRV_NAME,
+	.queuecommand		= ata_scsi_queuecmd,
+	.eh_strategy_handler	= ata_scsi_error,
+	.can_queue		= ATA_DEF_QUEUE,
+	.this_id		= ATA_SHT_THIS_ID,
+	.sg_tablesize		= AHCI_MAX_SG,
+	.max_sectors		= ATA_MAX_SECTORS,
+	.cmd_per_lun		= ATA_SHT_CMD_PER_LUN,
+	.emulated		= ATA_SHT_EMULATED,
+	.use_clustering		= AHCI_USE_CLUSTERING,
+	.proc_name		= DRV_NAME,
+	.dma_boundary		= AHCI_DMA_BOUNDARY,
+	.slave_configure	= ata_scsi_slave_config,
+	.bios_param		= ata_std_bios_param,
+};
+
+static struct ata_port_operations ahci_ops = {
+	.port_disable		= ata_port_disable,
+
+	.check_status		= ahci_check_status,
+	.dev_select		= ata_noop_dev_select,
+
+	.phy_reset		= ahci_phy_reset,
+
+	.qc_prep		= ahci_qc_prep,
+	.qc_issue		= ahci_qc_issue,
+
+	.eng_timeout		= ahci_eng_timeout,
+
+	.irq_handler		= ahci_interrupt,
+	.irq_clear		= ahci_irq_clear,
+
+	.scr_read		= ahci_scr_read,
+	.scr_write		= ahci_scr_write,
+
+	.port_start		= ahci_port_start,
+	.port_stop		= ahci_port_stop,
+	.host_stop		= ahci_host_stop,
+};
+
+static struct ata_port_info ahci_port_info[] = {
+	/* board_ahci */
+	{
+		.sht		= &ahci_sht,
+		.host_flags	= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
+				  ATA_FLAG_SATA_RESET | ATA_FLAG_MMIO,
+		.pio_mask	= 0x03, /* pio3-4 */
+		.udma_mask	= 0x7f, /* udma0-6 ; FIXME */
+		.port_ops	= &ahci_ops,
+	},
+};
+
+static struct pci_device_id ahci_pci_tbl[] = {
+	{ PCI_VENDOR_ID_INTEL, 0x2652, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+	  board_ahci },
+	{ PCI_VENDOR_ID_INTEL, 0x2653, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+	  board_ahci },
+	{ }	/* terminate list */
+};
+
+
+static struct pci_driver ahci_pci_driver = {
+	.name			= DRV_NAME,
+	.id_table		= ahci_pci_tbl,
+	.probe			= ahci_init_one,
+	.remove			= ata_pci_remove_one,
+};
+
+
+static inline unsigned long ahci_port_base_ul (unsigned long base, unsigned int port)
+{
+	return base + 0x100 + (port * 0x80);
+}
+
+static inline void *ahci_port_base (void *base, unsigned int port)
+{
+	return (void *) ahci_port_base_ul((unsigned long)base, port);
+}
+
+static void ahci_host_stop(struct ata_host_set *host_set)
+{
+	struct ahci_host_priv *hpriv = host_set->private_data;
+	kfree(hpriv);
+}
+
+static int ahci_port_start(struct ata_port *ap)
+{
+	struct pci_dev *pdev = ap->host_set->pdev;
+	struct ahci_host_priv *hpriv = ap->host_set->private_data;
+	struct ahci_port_priv *pp;
+	int rc;
+	void *mem, *mmio = ap->host_set->mmio_base;
+	void *port_mmio = ahci_port_base(mmio, ap->port_no);
+	dma_addr_t mem_dma;
+
+	rc = ata_port_start(ap);
+	if (rc)
+		return rc;
+
+	pp = kmalloc(sizeof(*pp), GFP_KERNEL);
+	if (!pp) {
+		rc = -ENOMEM;
+		goto err_out;
+	}
+	memset(pp, 0, sizeof(*pp));
+
+	mem = pci_alloc_consistent(pdev, AHCI_PORT_PRIV_DMA_SZ, &mem_dma);
+	if (!mem) {
+		rc = -ENOMEM;
+		goto err_out_kfree;
+	}
+	memset(mem, 0, AHCI_PORT_PRIV_DMA_SZ);
+
+	/*
+	 * First item in chunk of DMA memory: 32-slot command table,
+	 * 32 bytes each in size
+	 */
+	pp->cmd_slot = mem;
+	pp->cmd_slot_dma = mem_dma;
+
+	mem += AHCI_CMD_SLOT_SZ;
+	mem_dma += AHCI_CMD_SLOT_SZ;
+
+	/*
+	 * Second item: Received-FIS area
+	 */
+	pp->rx_fis = mem;
+	pp->rx_fis_dma = mem_dma;
+
+	mem += AHCI_RX_FIS_SZ;
+	mem_dma += AHCI_RX_FIS_SZ;
+
+	/*
+	 * Third item: data area for storing a single command
+	 * and its scatter-gather table
+	 */
+	pp->cmd_tbl = mem;
+	pp->cmd_tbl_dma = mem_dma;
+
+	pp->cmd_tbl_sg = mem + AHCI_CMD_TBL_HDR;
+
+	ap->private_data = pp;
+
+	if (hpriv->cap & HOST_CAP_64)
+		writel((pp->cmd_slot_dma >> 16) >> 16, port_mmio + PORT_LST_ADDR_HI);
+	writel(pp->cmd_slot_dma & 0xffffffff, port_mmio + PORT_LST_ADDR);
+	readl(port_mmio + PORT_LST_ADDR); /* flush */
+
+	if (hpriv->cap & HOST_CAP_64)
+		writel((pp->rx_fis_dma >> 16) >> 16, port_mmio + PORT_FIS_ADDR_HI);
+	writel(pp->rx_fis_dma & 0xffffffff, port_mmio + PORT_LST_ADDR);
+	readl(port_mmio + PORT_LST_ADDR); /* flush */
+
+	writel(PORT_CMD_ICC_ACTIVE | PORT_CMD_FIS_RX |
+	       PORT_CMD_POWER_ON | PORT_CMD_SPIN_UP |
+	       PORT_CMD_START, port_mmio + PORT_CMD);
+	readl(port_mmio + PORT_CMD); /* flush */
+
+	return 0;
+
+err_out_kfree:
+	kfree(pp);
+err_out:
+	ata_port_stop(ap);
+	return rc;
+}
+
+
+static void ahci_port_stop(struct ata_port *ap)
+{
+	struct pci_dev *pdev = ap->host_set->pdev;
+	struct ahci_port_priv *pp = ap->private_data;
+	void *mmio = ap->host_set->mmio_base;
+	void *port_mmio = ahci_port_base(mmio, ap->port_no);
+	u32 tmp;
+
+	tmp = readl(port_mmio + PORT_CMD);
+	tmp &= ~(PORT_CMD_START | PORT_CMD_FIS_RX);
+	writel(tmp, port_mmio + PORT_CMD);
+	readl(port_mmio + PORT_CMD); /* flush */
+
+	/* spec says 500 msecs for each PORT_CMD_{START,FIS_RX} bit, so
+	 * this is slightly incorrect.
+	 */
+	set_current_state(TASK_UNINTERRUPTIBLE);
+	schedule_timeout((HZ / 2) + 1);
+
+	ap->private_data = NULL;
+	pci_free_consistent(pdev, AHCI_PORT_PRIV_DMA_SZ,
+			    pp->cmd_slot, pp->cmd_slot_dma);
+	kfree(pp);
+	ata_port_stop(ap);
+}
+
+static u32 ahci_scr_read (struct ata_port *ap, unsigned int sc_reg_in)
+{
+	unsigned int sc_reg;
+
+	switch (sc_reg_in) {
+	case SCR_STATUS:	sc_reg = 0; break;
+	case SCR_CONTROL:	sc_reg = 1; break;
+	case SCR_ERROR:		sc_reg = 2; break;
+	case SCR_ACTIVE:	sc_reg = 3; break;
+	default:
+		return 0xffffffffU;
+	}
+
+	return readl((void *) ap->ioaddr.scr_addr + (sc_reg * 4));
+}
+
+
+static void ahci_scr_write (struct ata_port *ap, unsigned int sc_reg_in,
+			       u32 val)
+{
+	unsigned int sc_reg;
+
+	switch (sc_reg_in) {
+	case SCR_STATUS:	sc_reg = 0; break;
+	case SCR_CONTROL:	sc_reg = 1; break;
+	case SCR_ERROR:		sc_reg = 2; break;
+	case SCR_ACTIVE:	sc_reg = 3; break;
+	default:
+		return;
+	}
+
+	writel(val, (void *) ap->ioaddr.scr_addr + (sc_reg * 4));
+}
+
+static void ahci_phy_reset(struct ata_port *ap)
+{
+	void __iomem *port_mmio = (void __iomem *) ap->ioaddr.cmd_addr;
+	struct ata_taskfile tf;
+	struct ata_device *dev = &ap->device[0];
+	u32 tmp;
+
+	__sata_phy_reset(ap);
+
+	if (ap->flags & ATA_FLAG_PORT_DISABLED)
+		return;
+
+	tmp = readl(port_mmio + PORT_SIG);
+	tf.lbah		= (tmp >> 24)	& 0xff;
+	tf.lbam		= (tmp >> 16)	& 0xff;
+	tf.lbal		= (tmp >> 8)	& 0xff;
+	tf.nsect	= (tmp)		& 0xff;
+
+	dev->class = ata_dev_classify(&tf);
+	if (!ata_dev_present(dev))
+		ata_port_disable(ap);
+}
+
+static u8 ahci_check_status(struct ata_port *ap)
+{
+	void *mmio = (void *) ap->ioaddr.cmd_addr;
+
+	return readl(mmio + PORT_TFDATA) & 0xFF;
+}
+
+static void ahci_fill_sg(struct ata_queued_cmd *qc)
+{
+	struct ahci_port_priv *pp = qc->ap->private_data;
+	unsigned int i;
+
+	VPRINTK("ENTER\n");
+
+	/*
+	 * Next, the S/G list.
+	 */
+	for (i = 0; i < qc->n_elem; i++) {
+		u32 sg_len;
+		dma_addr_t addr;
+
+		addr = sg_dma_address(&qc->sg[i]);
+		sg_len = sg_dma_len(&qc->sg[i]);
+
+		pp->cmd_tbl_sg[i].addr = cpu_to_le32(addr & 0xffffffff);
+		pp->cmd_tbl_sg[i].addr_hi = cpu_to_le32((addr >> 16) >> 16);
+		pp->cmd_tbl_sg[i].flags_size = cpu_to_le32(sg_len - 1);
+	}
+}
+
+static void ahci_qc_prep(struct ata_queued_cmd *qc)
+{
+	struct ahci_port_priv *pp = qc->ap->private_data;
+	u32 opts;
+	const u32 cmd_fis_len = 5; /* five dwords */
+
+	/*
+	 * Fill in command slot information (currently only one slot,
+	 * slot 0, is currently since we don't do queueing)
+	 */
+
+	opts = (qc->n_elem << 16) | cmd_fis_len;
+	if (qc->tf.flags & ATA_TFLAG_WRITE)
+		opts |= AHCI_CMD_WRITE;
+
+	switch (qc->tf.protocol) {
+	case ATA_PROT_ATAPI:
+	case ATA_PROT_ATAPI_NODATA:
+	case ATA_PROT_ATAPI_DMA:
+		opts |= AHCI_CMD_ATAPI;
+		break;
+
+	default:
+		/* do nothing */
+		break;
+	}
+
+	pp->cmd_slot[0].opts = cpu_to_le32(opts);
+	pp->cmd_slot[0].status = 0;
+	pp->cmd_slot[0].tbl_addr = cpu_to_le32(pp->cmd_tbl_dma & 0xffffffff);
+	pp->cmd_slot[0].tbl_addr_hi = cpu_to_le32((pp->cmd_tbl_dma >> 16) >> 16);
+
+	/*
+	 * Fill in command table information.  First, the header,
+	 * a SATA Register - Host to Device command FIS.
+	 */
+	ata_tf_to_fis(&qc->tf, pp->cmd_tbl, 0);
+
+	if (!(qc->flags & ATA_QCFLAG_DMAMAP))
+		return;
+
+	ahci_fill_sg(qc);
+}
+
+static inline void ahci_dma_complete (struct ata_port *ap,
+                                     struct ata_queued_cmd *qc,
+				     int have_err)
+{
+	/* get drive status; clear intr; complete txn */
+	ata_qc_complete(ata_qc_from_tag(ap, ap->active_tag),
+			have_err ? ATA_ERR : 0);
+}
+
+static void ahci_intr_error(struct ata_port *ap, u32 irq_stat)
+{
+	void *mmio = ap->host_set->mmio_base;
+	void *port_mmio = ahci_port_base(mmio, ap->port_no);
+	u32 tmp;
+	int work;
+
+	/* stop DMA */
+	tmp = readl(port_mmio + PORT_CMD);
+	tmp &= PORT_CMD_START | PORT_CMD_FIS_RX;
+	writel(tmp, port_mmio + PORT_CMD);
+
+	/* wait for engine to stop.  TODO: this could be
+	 * as long as 500 msec
+	 */
+	work = 1000;
+	while (work-- > 0) {
+		tmp = readl(port_mmio + PORT_CMD);
+		if ((tmp & PORT_CMD_LIST_ON) == 0)
+			break;
+		udelay(10);
+	}
+
+	/* clear SATA phy error, if any */
+	tmp = readl(port_mmio + PORT_SCR_ERR);
+	writel(tmp, port_mmio + PORT_SCR_ERR);
+
+	/* if DRQ/BSY is set, device needs to be reset.
+	 * if so, issue COMRESET
+	 */
+	tmp = readl(port_mmio + PORT_TFDATA);
+	if (tmp & (ATA_BUSY | ATA_DRQ)) {
+		writel(0x301, port_mmio + PORT_SCR_CTL);
+		readl(port_mmio + PORT_SCR_CTL); /* flush */
+		udelay(10);
+		writel(0x300, port_mmio + PORT_SCR_CTL);
+		readl(port_mmio + PORT_SCR_CTL); /* flush */
+	}
+
+	/* re-start DMA */
+	tmp = readl(port_mmio + PORT_CMD);
+	tmp |= PORT_CMD_START | PORT_CMD_FIS_RX;
+	writel(tmp, port_mmio + PORT_CMD);
+	readl(port_mmio + PORT_CMD); /* flush */
+
+	printk(KERN_WARNING "ata%u: error occurred, port reset\n", ap->port_no);
+}
+
+static void ahci_eng_timeout(struct ata_port *ap)
+{
+	void *mmio = ap->host_set->mmio_base;
+	void *port_mmio = ahci_port_base(mmio, ap->port_no);
+	struct ata_queued_cmd *qc;
+
+	DPRINTK("ENTER\n");
+
+	ahci_intr_error(ap, readl(port_mmio + PORT_IRQ_STAT));
+
+	qc = ata_qc_from_tag(ap, ap->active_tag);
+	if (!qc) {
+		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
+		       ap->id);
+	} else {
+		/* hack alert!  We cannot use the supplied completion
+	 	 * function from inside the ->eh_strategy_handler() thread.
+	 	 * libata is the only user of ->eh_strategy_handler() in
+	 	 * any kernel, so the default scsi_done() assumes it is
+	 	 * not being called from the SCSI EH.
+	 	 */
+		qc->scsidone = scsi_finish_command;
+		ata_qc_complete(qc, ATA_ERR);
+	}
+
+}
+
+static inline int ahci_host_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
+{
+	void *mmio = ap->host_set->mmio_base;
+	void *port_mmio = ahci_port_base(mmio, ap->port_no);
+	u32 status, serr, ci;
+
+	serr = readl(port_mmio + PORT_SCR_ERR);
+	writel(serr, port_mmio + PORT_SCR_ERR);
+
+	status = readl(port_mmio + PORT_IRQ_STAT);
+	writel(status, port_mmio + PORT_IRQ_STAT);
+
+	ci = readl(port_mmio + PORT_CMD_ISSUE);
+	if (likely((ci & 0x1) == 0)) {
+		if (qc) {
+			ata_qc_complete(qc, 0);
+			qc = NULL;
+		}
+	}
+
+	if (status & PORT_IRQ_FATAL) {
+		ahci_intr_error(ap, status);
+		if (qc)
+			ata_qc_complete(qc, ATA_ERR);
+	}
+
+	return 1;
+}
+
+static void ahci_irq_clear(struct ata_port *ap)
+{
+	/* TODO */
+}
+
+static irqreturn_t ahci_interrupt (int irq, void *dev_instance, struct pt_regs *regs)
+{
+	struct ata_host_set *host_set = dev_instance;
+	struct ahci_host_priv *hpriv;
+	unsigned int i, handled = 0;
+	void *mmio;
+	u32 irq_stat, irq_ack = 0;
+
+	VPRINTK("ENTER\n");
+
+	hpriv = host_set->private_data;
+	mmio = host_set->mmio_base;
+
+	/* sigh.  0xffffffff is a valid return from h/w */
+	irq_stat = readl(mmio + HOST_IRQ_STAT);
+	irq_stat &= hpriv->port_map;
+	if (!irq_stat)
+		return IRQ_NONE;
+
+        spin_lock(&host_set->lock);
+
+        for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap;
+		u32 tmp;
+
+		VPRINTK("port %u\n", i);
+		ap = host_set->ports[i];
+		tmp = irq_stat & (1 << i);
+		if (tmp && ap) {
+			struct ata_queued_cmd *qc;
+			qc = ata_qc_from_tag(ap, ap->active_tag);
+			if (ahci_host_intr(ap, qc))
+				irq_ack |= (1 << i);
+		}
+	}
+
+	if (irq_ack) {
+		writel(irq_ack, mmio + HOST_IRQ_STAT);
+		handled = 1;
+	}
+
+        spin_unlock(&host_set->lock);
+
+	VPRINTK("EXIT\n");
+
+	return IRQ_RETVAL(handled);
+}
+
+static int ahci_qc_issue(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	void *mmio = (void *) ap->ioaddr.cmd_addr;
+
+	writel(1, mmio + PORT_CMD_ISSUE);
+	readl(mmio + PORT_CMD_ISSUE);	/* flush */
+
+	return 0;
+}
+
+static void ahci_setup_port(struct ata_ioports *port, unsigned long base,
+			    unsigned int port_idx)
+{
+	VPRINTK("ENTER, base==0x%lx, port_idx %u\n", base, port_idx);
+	base = ahci_port_base_ul(base, port_idx);
+	VPRINTK("base now==0x%lx\n", base);
+
+	port->cmd_addr		= base;
+	port->scr_addr		= base + PORT_SCR;
+
+	VPRINTK("EXIT\n");
+}
+
+static int ahci_host_init(struct ata_probe_ent *probe_ent)
+{
+	struct ahci_host_priv *hpriv = probe_ent->private_data;
+	struct pci_dev *pdev = probe_ent->pdev;
+	void __iomem *mmio = probe_ent->mmio_base;
+	u32 tmp, cap_save;
+	u16 tmp16;
+	unsigned int i, j, using_dac;
+	int rc;
+	void __iomem *port_mmio;
+
+	cap_save = readl(mmio + HOST_CAP);
+	cap_save &= ( (1<<28) | (1<<17) );
+	cap_save |= (1 << 27);
+
+	/* global controller reset */
+	tmp = readl(mmio + HOST_CTL);
+	if ((tmp & HOST_RESET) == 0) {
+		writel(tmp | HOST_RESET, mmio + HOST_CTL);
+		readl(mmio + HOST_CTL); /* flush */
+	}
+
+	/* reset must complete within 1 second, or
+	 * the hardware should be considered fried.
+	 */
+	set_current_state(TASK_UNINTERRUPTIBLE);
+	schedule_timeout(HZ + 1);
+
+	tmp = readl(mmio + HOST_CTL);
+	if (tmp & HOST_RESET) {
+		printk(KERN_ERR DRV_NAME "(%s): controller reset failed (0x%x)\n",
+			pci_name(pdev), tmp);
+		return -EIO;
+	}
+
+	writel(HOST_AHCI_EN, mmio + HOST_CTL);
+	(void) readl(mmio + HOST_CTL);	/* flush */
+	writel(cap_save, mmio + HOST_CAP);
+	writel(0xf, mmio + HOST_PORTS_IMPL);
+	(void) readl(mmio + HOST_PORTS_IMPL);	/* flush */
+
+	pci_read_config_word(pdev, 0x92, &tmp16);
+	tmp16 |= 0xf;
+	pci_write_config_word(pdev, 0x92, tmp16);
+
+	hpriv->cap = readl(mmio + HOST_CAP);
+	hpriv->port_map = readl(mmio + HOST_PORTS_IMPL);
+	probe_ent->n_ports = (hpriv->cap & 0x1f) + 1;
+
+	VPRINTK("cap 0x%x  port_map 0x%x  n_ports %d\n",
+		hpriv->cap, hpriv->port_map, probe_ent->n_ports);
+
+	using_dac = hpriv->cap & HOST_CAP_64;
+	if (using_dac &&
+	    !pci_set_dma_mask(pdev, 0xffffffffffffffffULL)) {
+		rc = pci_set_consistent_dma_mask(pdev, 0xffffffffffffffffULL);
+		if (rc) {
+			rc = pci_set_consistent_dma_mask(pdev, 0xffffffffULL);
+			if (rc) {
+				printk(KERN_ERR DRV_NAME "(%s): 64-bit DMA enable failed\n",
+					pci_name(pdev));
+				return rc;
+			}
+		}
+
+		hpriv->flags |= HOST_CAP_64;
+	} else {
+		rc = pci_set_dma_mask(pdev, 0xffffffffULL);
+		if (rc) {
+			printk(KERN_ERR DRV_NAME "(%s): 32-bit DMA enable failed\n",
+				pci_name(pdev));
+			return rc;
+		}
+		rc = pci_set_consistent_dma_mask(pdev, 0xffffffffULL);
+		if (rc) {
+			printk(KERN_ERR DRV_NAME "(%s): 32-bit consistent DMA enable failed\n",
+				pci_name(pdev));
+			return rc;
+		}
+	}
+
+	for (i = 0; i < probe_ent->n_ports; i++) {
+		if (!(hpriv->port_map & (1 << i)))
+			continue;
+
+		port_mmio = ahci_port_base(mmio, i);
+		VPRINTK("mmio %p  port_mmio %p\n", mmio, port_mmio);
+
+		ahci_setup_port(&probe_ent->port[i],
+				(unsigned long) mmio, i);
+
+		/* make sure port is not active */
+		tmp = readl(port_mmio + PORT_CMD);
+		VPRINTK("PORT_CMD 0x%x\n", tmp);
+		if (tmp & (PORT_CMD_LIST_ON | PORT_CMD_FIS_ON |
+			   PORT_CMD_FIS_RX | PORT_CMD_START)) {
+			tmp &= ~(PORT_CMD_LIST_ON | PORT_CMD_FIS_ON |
+				 PORT_CMD_FIS_RX | PORT_CMD_START);
+			writel(tmp, port_mmio + PORT_CMD);
+			readl(port_mmio + PORT_CMD); /* flush */
+
+			/* spec says 500 msecs for each bit, so
+			 * this is slightly incorrect.
+			 */
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			schedule_timeout((HZ / 2) + 1);
+		}
+
+		writel(PORT_CMD_SPIN_UP, port_mmio + PORT_CMD);
+
+		j = 0;
+		while (j < 100) {
+			msleep(10);
+			tmp = readl(port_mmio + PORT_SCR_STAT);
+			if ((tmp & 0xf) == 0x3)
+				break;
+			j++;
+		}
+
+		tmp = readl(port_mmio + PORT_SCR_ERR);
+		VPRINTK("PORT_SCR_ERR 0x%x\n", tmp);
+		writel(tmp, port_mmio + PORT_SCR_ERR);
+
+		/* ack any pending irq events for this port */
+		tmp = readl(port_mmio + PORT_IRQ_STAT);
+		VPRINTK("PORT_IRQ_STAT 0x%x\n", tmp);
+		if (tmp)
+			writel(tmp, port_mmio + PORT_IRQ_STAT);
+
+		writel(1 << i, mmio + HOST_IRQ_STAT);
+
+		/* set irq mask (enables interrupts) */
+		writel(DEF_PORT_IRQ, port_mmio + PORT_IRQ_MASK);
+	}
+
+	tmp = readl(mmio + HOST_CTL);
+	VPRINTK("HOST_CTL 0x%x\n", tmp);
+	writel(tmp | HOST_IRQ_EN, mmio + HOST_CTL);
+	tmp = readl(mmio + HOST_CTL);
+	VPRINTK("HOST_CTL 0x%x\n", tmp);
+
+	pci_set_master(pdev);
+
+	return 0;
+}
+
+/* move to PCI layer, integrate w/ MSI stuff */
+static void pci_enable_intx(struct pci_dev *pdev)
+{
+	u16 pci_command;
+
+	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
+	if (pci_command & PCI_COMMAND_INTX_DISABLE) {
+		pci_command &= ~PCI_COMMAND_INTX_DISABLE;
+		pci_write_config_word(pdev, PCI_COMMAND, pci_command);
+	}
+}
+
+static void ahci_print_info(struct ata_probe_ent *probe_ent)
+{
+	struct ahci_host_priv *hpriv = probe_ent->private_data;
+	struct pci_dev *pdev = probe_ent->pdev;
+	void *mmio = probe_ent->mmio_base;
+	u32 vers, cap, impl, speed;
+	const char *speed_s;
+
+	vers = readl(mmio + HOST_VERSION);
+	cap = hpriv->cap;
+	impl = hpriv->port_map;
+
+	speed = (cap >> 20) & 0xf;
+	if (speed == 1)
+		speed_s = "1.5";
+	else if (speed == 2)
+		speed_s = "3";
+	else
+		speed_s = "?";
+
+	printk(KERN_INFO DRV_NAME "(%s) AHCI %02x%02x.%02x%02x "
+		"%u slots %u ports %s Gbps 0x%x impl\n"
+	       	,
+	       	pci_name(pdev),
+
+	       	(vers >> 24) & 0xff,
+	       	(vers >> 16) & 0xff,
+	       	(vers >> 8) & 0xff,
+	       	vers & 0xff,
+
+		((cap >> 8) & 0x1f) + 1,
+		(cap & 0x1f) + 1,
+		speed_s,
+		impl);
+
+	printk(KERN_INFO DRV_NAME "(%s) flags: "
+	       	"%s%s%s%s%s%s"
+	       	"%s%s%s%s%s%s%s\n"
+	       	,
+	       	pci_name(pdev),
+
+		cap & (1 << 31) ? "64bit " : "",
+		cap & (1 << 30) ? "ncq " : "",
+		cap & (1 << 28) ? "ilck " : "",
+		cap & (1 << 27) ? "stag " : "",
+		cap & (1 << 26) ? "pm " : "",
+		cap & (1 << 25) ? "led " : "",
+
+		cap & (1 << 24) ? "clo " : "",
+		cap & (1 << 19) ? "nz " : "",
+		cap & (1 << 18) ? "only " : "",
+		cap & (1 << 17) ? "pmp " : "",
+		cap & (1 << 15) ? "pio " : "",
+		cap & (1 << 14) ? "slum " : "",
+		cap & (1 << 13) ? "part " : ""
+		);
+}
+
+static int ahci_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	static int printed_version;
+	struct ata_probe_ent *probe_ent = NULL;
+	struct ahci_host_priv *hpriv;
+	unsigned long base;
+	void *mmio_base;
+	unsigned int board_idx = (unsigned int) ent->driver_data;
+	int rc;
+
+	VPRINTK("ENTER\n");
+
+	if (!printed_version++)
+		printk(KERN_DEBUG DRV_NAME " version " DRV_VERSION "\n");
+
+	/*
+	 * If this driver happens to only be useful on Apple's K2, then
+	 * we should check that here as it has a normal Serverworks ID
+	 */
+	rc = pci_enable_device(pdev);
+	if (rc)
+		return rc;
+
+	rc = pci_request_regions(pdev, DRV_NAME);
+	if (rc)
+		goto err_out;
+
+	pci_enable_intx(pdev);
+
+	probe_ent = kmalloc(sizeof(*probe_ent), GFP_KERNEL);
+	if (probe_ent == NULL) {
+		rc = -ENOMEM;
+		goto err_out_regions;
+	}
+
+	memset(probe_ent, 0, sizeof(*probe_ent));
+	probe_ent->pdev = pdev;
+	INIT_LIST_HEAD(&probe_ent->node);
+
+	mmio_base = ioremap(pci_resource_start(pdev, AHCI_PCI_BAR),
+		            pci_resource_len(pdev, AHCI_PCI_BAR));
+	if (mmio_base == NULL) {
+		rc = -ENOMEM;
+		goto err_out_free_ent;
+	}
+	base = (unsigned long) mmio_base;
+
+	hpriv = kmalloc(sizeof(*hpriv), GFP_KERNEL);
+	if (!hpriv) {
+		rc = -ENOMEM;
+		goto err_out_iounmap;
+	}
+	memset(hpriv, 0, sizeof(*hpriv));
+
+	probe_ent->sht		= ahci_port_info[board_idx].sht;
+	probe_ent->host_flags	= ahci_port_info[board_idx].host_flags;
+	probe_ent->pio_mask	= ahci_port_info[board_idx].pio_mask;
+	probe_ent->udma_mask	= ahci_port_info[board_idx].udma_mask;
+	probe_ent->port_ops	= ahci_port_info[board_idx].port_ops;
+
+       	probe_ent->irq = pdev->irq;
+       	probe_ent->irq_flags = SA_SHIRQ;
+	probe_ent->mmio_base = mmio_base;
+	probe_ent->private_data = hpriv;
+
+	/* initialize adapter */
+	rc = ahci_host_init(probe_ent);
+	if (rc)
+		goto err_out_hpriv;
+
+	ahci_print_info(probe_ent);
+
+	/* FIXME: check ata_device_add return value */
+	ata_device_add(probe_ent);
+	kfree(probe_ent);
+
+	return 0;
+
+err_out_hpriv:
+	kfree(hpriv);
+err_out_iounmap:
+	iounmap(mmio_base);
+err_out_free_ent:
+	kfree(probe_ent);
+err_out_regions:
+	pci_release_regions(pdev);
+err_out:
+	pci_disable_device(pdev);
+	return rc;
+}
+
+
+static int __init ahci_init(void)
+{
+	return pci_module_init(&ahci_pci_driver);
+}
+
+
+static void __exit ahci_exit(void)
+{
+	pci_unregister_driver(&ahci_pci_driver);
+}
+
+
+MODULE_AUTHOR("Jeff Garzik");
+MODULE_DESCRIPTION("AHCI SATA low-level driver");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(pci, ahci_pci_tbl);
+
+module_init(ahci_init);
+module_exit(ahci_exit);