libata-sff.c

linux 内核源代码

/**
 *	ata_bmdma_error_handler - Stock error handler for BMDMA controller
 *	@ap: port to handle error for
 *
 *	Stock error handler for BMDMA controller.
 *
 *	LOCKING:
 *	Kernel thread context (may sleep)
 */
void ata_bmdma_error_handler(struct ata_port *ap)
{
	ata_reset_fn_t hardreset;

	hardreset = NULL;
	if (sata_scr_valid(&ap->link))
		hardreset = sata_std_hardreset;

	ata_bmdma_drive_eh(ap, ata_std_prereset, ata_std_softreset, hardreset,
			   ata_std_postreset);
}

/**
 *	ata_bmdma_post_internal_cmd - Stock post_internal_cmd for
 *				      BMDMA controller
 *	@qc: internal command to clean up
 *
 *	LOCKING:
 *	Kernel thread context (may sleep)
 */
void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc)
{
	if (qc->ap->ioaddr.bmdma_addr)
		ata_bmdma_stop(qc);
}

/**
 *	ata_sff_port_start - Set port up for dma.
 *	@ap: Port to initialize
 *
 *	Called just after data structures for each port are
 *	initialized.  Allocates space for PRD table if the device
 *	is DMA capable SFF.
 *
 *	May be used as the port_start() entry in ata_port_operations.
 *
 *	LOCKING:
 *	Inherited from caller.
 */

int ata_sff_port_start(struct ata_port *ap)
{
	if (ap->ioaddr.bmdma_addr)
		return ata_port_start(ap);
	return 0;
}

#ifdef CONFIG_PCI

static int ata_resources_present(struct pci_dev *pdev, int port)
{
	int i;

	/* Check the PCI resources for this channel are enabled */
	port = port * 2;
	for (i = 0; i < 2; i ++) {
		if (pci_resource_start(pdev, port + i) == 0 ||
		    pci_resource_len(pdev, port + i) == 0)
			return 0;
	}
	return 1;
}

/**
 *	ata_pci_init_bmdma - acquire PCI BMDMA resources and init ATA host
 *	@host: target ATA host
 *
 *	Acquire PCI BMDMA resources and initialize @host accordingly.
 *
 *	LOCKING:
 *	Inherited from calling layer (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno otherwise.
 */
int ata_pci_init_bmdma(struct ata_host *host)
{
	struct device *gdev = host->dev;
	struct pci_dev *pdev = to_pci_dev(gdev);
	int i, rc;

	/* No BAR4 allocation: No DMA */
	if (pci_resource_start(pdev, 4) == 0)
		return 0;

	/* TODO: If we get no DMA mask we should fall back to PIO */
	rc = pci_set_dma_mask(pdev, ATA_DMA_MASK);
	if (rc)
		return rc;
	rc = pci_set_consistent_dma_mask(pdev, ATA_DMA_MASK);
	if (rc)
		return rc;

	/* request and iomap DMA region */
	rc = pcim_iomap_regions(pdev, 1 << 4, DRV_NAME);
	if (rc) {
		dev_printk(KERN_ERR, gdev, "failed to request/iomap BAR4\n");
		return -ENOMEM;
	}
	host->iomap = pcim_iomap_table(pdev);

	for (i = 0; i < 2; i++) {
		struct ata_port *ap = host->ports[i];
		void __iomem *bmdma = host->iomap[4] + 8 * i;

		if (ata_port_is_dummy(ap))
			continue;

		ap->ioaddr.bmdma_addr = bmdma;
		if ((!(ap->flags & ATA_FLAG_IGN_SIMPLEX)) &&
		    (ioread8(bmdma + 2) & 0x80))
			host->flags |= ATA_HOST_SIMPLEX;

		ata_port_desc(ap, "bmdma 0x%llx",
			(unsigned long long)pci_resource_start(pdev, 4) + 8 * i);
	}

	return 0;
}

/**
 *	ata_pci_init_sff_host - acquire native PCI ATA resources and init host
 *	@host: target ATA host
 *
 *	Acquire native PCI ATA resources for @host and initialize the
 *	first two ports of @host accordingly.  Ports marked dummy are
 *	skipped and allocation failure makes the port dummy.
 *
 *	Note that native PCI resources are valid even for legacy hosts
 *	as we fix up pdev resources array early in boot, so this
 *	function can be used for both native and legacy SFF hosts.
 *
 *	LOCKING:
 *	Inherited from calling layer (may sleep).
 *
 *	RETURNS:
 *	0 if at least one port is initialized, -ENODEV if no port is
 *	available.
 */
int ata_pci_init_sff_host(struct ata_host *host)
{
	struct device *gdev = host->dev;
	struct pci_dev *pdev = to_pci_dev(gdev);
	unsigned int mask = 0;
	int i, rc;

	/* request, iomap BARs and init port addresses accordingly */
	for (i = 0; i < 2; i++) {
		struct ata_port *ap = host->ports[i];
		int base = i * 2;
		void __iomem * const *iomap;

		if (ata_port_is_dummy(ap))
			continue;

		/* Discard disabled ports.  Some controllers show
		 * their unused channels this way.  Disabled ports are
		 * made dummy.
		 */
		if (!ata_resources_present(pdev, i)) {
			ap->ops = &ata_dummy_port_ops;
			continue;
		}

		rc = pcim_iomap_regions(pdev, 0x3 << base, DRV_NAME);
		if (rc) {
			dev_printk(KERN_WARNING, gdev,
				   "failed to request/iomap BARs for port %d "
				   "(errno=%d)\n", i, rc);
			if (rc == -EBUSY)
				pcim_pin_device(pdev);
			ap->ops = &ata_dummy_port_ops;
			continue;
		}
		host->iomap = iomap = pcim_iomap_table(pdev);

		ap->ioaddr.cmd_addr = iomap[base];
		ap->ioaddr.altstatus_addr =
		ap->ioaddr.ctl_addr = (void __iomem *)
			((unsigned long)iomap[base + 1] | ATA_PCI_CTL_OFS);
		ata_std_ports(&ap->ioaddr);

		ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
			(unsigned long long)pci_resource_start(pdev, base),
			(unsigned long long)pci_resource_start(pdev, base + 1));

		mask |= 1 << i;
	}

	if (!mask) {
		dev_printk(KERN_ERR, gdev, "no available native port\n");
		return -ENODEV;
	}

	return 0;
}

/**
 *	ata_pci_prepare_sff_host - helper to prepare native PCI ATA host
 *	@pdev: target PCI device
 *	@ppi: array of port_info, must be enough for two ports
 *	@r_host: out argument for the initialized ATA host
 *
 *	Helper to allocate ATA host for @pdev, acquire all native PCI
 *	resources and initialize it accordingly in one go.
 *
 *	LOCKING:
 *	Inherited from calling layer (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno otherwise.
 */
int ata_pci_prepare_sff_host(struct pci_dev *pdev,
			     const struct ata_port_info * const * ppi,
			     struct ata_host **r_host)
{
	struct ata_host *host;
	int rc;

	if (!devres_open_group(&pdev->dev, NULL, GFP_KERNEL))
		return -ENOMEM;

	host = ata_host_alloc_pinfo(&pdev->dev, ppi, 2);
	if (!host) {
		dev_printk(KERN_ERR, &pdev->dev,
			   "failed to allocate ATA host\n");
		rc = -ENOMEM;
		goto err_out;
	}

	rc = ata_pci_init_sff_host(host);
	if (rc)
		goto err_out;

	/* init DMA related stuff */
	rc = ata_pci_init_bmdma(host);
	if (rc)
		goto err_bmdma;

	devres_remove_group(&pdev->dev, NULL);
	*r_host = host;
	return 0;

 err_bmdma:
	/* This is necessary because PCI and iomap resources are
	 * merged and releasing the top group won't release the
	 * acquired resources if some of those have been acquired
	 * before entering this function.
	 */
	pcim_iounmap_regions(pdev, 0xf);
 err_out:
	devres_release_group(&pdev->dev, NULL);
	return rc;
}

/**
 *	ata_pci_init_one - Initialize/register PCI IDE host controller
 *	@pdev: Controller to be initialized
 *	@ppi: array of port_info, must be enough for two ports
 *
 *	This is a helper function which can be called from a driver's
 *	xxx_init_one() probe function if the hardware uses traditional
 *	IDE taskfile registers.
 *
 *	This function calls pci_enable_device(), reserves its register
 *	regions, sets the dma mask, enables bus master mode, and calls
 *	ata_device_add()
 *
 *	ASSUMPTION:
 *	Nobody makes a single channel controller that appears solely as
 *	the secondary legacy port on PCI.
 *
 *	LOCKING:
 *	Inherited from PCI layer (may sleep).
 *
 *	RETURNS:
 *	Zero on success, negative on errno-based value on error.
 */
int ata_pci_init_one(struct pci_dev *pdev,
		     const struct ata_port_info * const * ppi)
{
	struct device *dev = &pdev->dev;
	const struct ata_port_info *pi = NULL;
	struct ata_host *host = NULL;
	u8 mask;
	int legacy_mode = 0;
	int i, rc;

	DPRINTK("ENTER\n");

	/* look up the first valid port_info */
	for (i = 0; i < 2 && ppi[i]; i++) {
		if (ppi[i]->port_ops != &ata_dummy_port_ops) {
			pi = ppi[i];
			break;
		}
	}

	if (!pi) {
		dev_printk(KERN_ERR, &pdev->dev,
			   "no valid port_info specified\n");
		return -EINVAL;
	}

	if (!devres_open_group(dev, NULL, GFP_KERNEL))
		return -ENOMEM;

	/* FIXME: Really for ATA it isn't safe because the device may be
	   multi-purpose and we want to leave it alone if it was already
	   enabled. Secondly for shared use as Arjan says we want refcounting

	   Checking dev->is_enabled is insufficient as this is not set at
	   boot for the primary video which is BIOS enabled
	  */

	rc = pcim_enable_device(pdev);
	if (rc)
		goto err_out;

	if ((pdev->class >> 8) == PCI_CLASS_STORAGE_IDE) {
		u8 tmp8;

		/* TODO: What if one channel is in native mode ... */
		pci_read_config_byte(pdev, PCI_CLASS_PROG, &tmp8);
		mask = (1 << 2) | (1 << 0);
		if ((tmp8 & mask) != mask)
			legacy_mode = 1;
#if defined(CONFIG_NO_ATA_LEGACY)
		/* Some platforms with PCI limits cannot address compat
		   port space. In that case we punt if their firmware has
		   left a device in compatibility mode */
		if (legacy_mode) {
			printk(KERN_ERR "ata: Compatibility mode ATA is not supported on this platform, skipping.\n");
			rc = -EOPNOTSUPP;
			goto err_out;
		}
#endif
	}

	/* prepare host */
	rc = ata_pci_prepare_sff_host(pdev, ppi, &host);
	if (rc)
		goto err_out;

	pci_set_master(pdev);

	/* start host and request IRQ */
	rc = ata_host_start(host);
	if (rc)
		goto err_out;

	if (!legacy_mode && pdev->irq) {
		/* We may have no IRQ assigned in which case we can poll. This
		   shouldn't happen on a sane system but robustness is cheap
		   in this case */
		rc = devm_request_irq(dev, pdev->irq, pi->port_ops->irq_handler,
				      IRQF_SHARED, DRV_NAME, host);
		if (rc)
			goto err_out;

		ata_port_desc(host->ports[0], "irq %d", pdev->irq);
		ata_port_desc(host->ports[1], "irq %d", pdev->irq);
	} else if (legacy_mode) {
		if (!ata_port_is_dummy(host->ports[0])) {
			rc = devm_request_irq(dev, ATA_PRIMARY_IRQ(pdev),
					      pi->port_ops->irq_handler,
					      IRQF_SHARED, DRV_NAME, host);
			if (rc)
				goto err_out;

			ata_port_desc(host->ports[0], "irq %d",
				      ATA_PRIMARY_IRQ(pdev));
		}

		if (!ata_port_is_dummy(host->ports[1])) {
			rc = devm_request_irq(dev, ATA_SECONDARY_IRQ(pdev),
					      pi->port_ops->irq_handler,
					      IRQF_SHARED, DRV_NAME, host);
			if (rc)
				goto err_out;

			ata_port_desc(host->ports[1], "irq %d",
				      ATA_SECONDARY_IRQ(pdev));
		}
	}

	/* register */
	rc = ata_host_register(host, pi->sht);
	if (rc)
		goto err_out;

	devres_remove_group(dev, NULL);
	return 0;

err_out:
	devres_release_group(dev, NULL);
	return rc;
}

/**
 *	ata_pci_clear_simplex	-	attempt to kick device out of simplex
 *	@pdev: PCI device
 *
 *	Some PCI ATA devices report simplex mode but in fact can be told to
 *	enter non simplex mode. This implements the necessary logic to
 *	perform the task on such devices. Calling it on other devices will
 *	have -undefined- behaviour.
 */

int ata_pci_clear_simplex(struct pci_dev *pdev)
{
	unsigned long bmdma = pci_resource_start(pdev, 4);
	u8 simplex;

	if (bmdma == 0)
		return -ENOENT;

	simplex = inb(bmdma + 0x02);
	outb(simplex & 0x60, bmdma + 0x02);
	simplex = inb(bmdma + 0x02);
	if (simplex & 0x80)
		return -EOPNOTSUPP;
	return 0;
}

unsigned long ata_pci_default_filter(struct ata_device *adev, unsigned long xfer_mask)
{
	/* Filter out DMA modes if the device has been configured by
	   the BIOS as PIO only */

	if (adev->link->ap->ioaddr.bmdma_addr == NULL)
		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
	return xfer_mask;
}

#endif /* CONFIG_PCI */