Commit 0be0aa98 authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik
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[PATCH] libata: improve driver initialization and deinitialization 



Implement ahci_[de]init_port() and use it during initialization and
de-initialization.  ahci_[de]init_port() are supersets of what used to
be done during driver [de-]initialization.  This patch makes the
following behavior changes.

* Per-port IRQ mask is cleared on driver load as done in other
  drivers.  The mask will be configured properly during probe.

* During init_one(), HOST_IRQ_STAT is cleared after masking port IRQs
  such that there is no race window.

* CMD_SPIN_UP is cleared during init_one() instead of being set.  It
  is set in port_start().  This is more consistent with overall
  structure of initialization.  Note that CMD_SPIN_UP simply controls
  PHY activation.

* Slumber and staggered spin-up are handled properly.

* All init/deinit operations are done in step-by-step manner as
  described in the spec instead of issued as single merged command.

Original implementation is from Zhao, Forrest <forrest.zhao@intel.com>

Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
Signed-off-by: default avatarZhao, Forrest <forrest.zhao@intel.com>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent 9f592056

drivers/scsi/ahci.c

+151 −51
Original line number Diff line number Diff line
@@ -92,7 +92,9 @@ enum { 
	HOST_AHCI_EN		= (1 << 31), /* AHCI enabled */



	/* HOST_CAP bits */

	HOST_CAP_SSC		= (1 << 14), /* Slumber capable */

	HOST_CAP_CLO		= (1 << 24), /* Command List Override support */

	HOST_CAP_SSS		= (1 << 27), /* Staggered Spin-up */

	HOST_CAP_NCQ		= (1 << 30), /* Native Command Queueing */

	HOST_CAP_64		= (1 << 31), /* PCI DAC (64-bit DMA) support */
@@ -155,6 +157,7 @@ enum { 
	PORT_CMD_SPIN_UP	= (1 << 1), /* Spin up device */

	PORT_CMD_START		= (1 << 0), /* Enable port DMA engine */



	PORT_CMD_ICC_MASK	= (0xf << 28), /* i/f ICC state mask */

	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 */
@@ -440,6 +443,135 @@ static int ahci_stop_engine(void __iomem *port_mmio) 
	return 0;

}



static void ahci_start_fis_rx(void __iomem *port_mmio, u32 cap,

			      dma_addr_t cmd_slot_dma, dma_addr_t rx_fis_dma)

{

	u32 tmp;



	/* set FIS registers */

	if (cap & HOST_CAP_64)

		writel((cmd_slot_dma >> 16) >> 16, port_mmio + PORT_LST_ADDR_HI);

	writel(cmd_slot_dma & 0xffffffff, port_mmio + PORT_LST_ADDR);



	if (cap & HOST_CAP_64)

		writel((rx_fis_dma >> 16) >> 16, port_mmio + PORT_FIS_ADDR_HI);

	writel(rx_fis_dma & 0xffffffff, port_mmio + PORT_FIS_ADDR);



	/* enable FIS reception */

	tmp = readl(port_mmio + PORT_CMD);

	tmp |= PORT_CMD_FIS_RX;

	writel(tmp, port_mmio + PORT_CMD);



	/* flush */

	readl(port_mmio + PORT_CMD);

}



static int ahci_stop_fis_rx(void __iomem *port_mmio)

{

	u32 tmp;



	/* disable FIS reception */

	tmp = readl(port_mmio + PORT_CMD);

	tmp &= ~PORT_CMD_FIS_RX;

	writel(tmp, port_mmio + PORT_CMD);



	/* wait for completion, spec says 500ms, give it 1000 */

	tmp = ata_wait_register(port_mmio + PORT_CMD, PORT_CMD_FIS_ON,

				PORT_CMD_FIS_ON, 10, 1000);

	if (tmp & PORT_CMD_FIS_ON)

		return -EBUSY;



	return 0;

}



static void ahci_power_up(void __iomem *port_mmio, u32 cap)

{

	u32 cmd;



	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;



	/* spin up device */

	if (cap & HOST_CAP_SSS) {

		cmd |= PORT_CMD_SPIN_UP;

		writel(cmd, port_mmio + PORT_CMD);

	}



	/* wake up link */

	writel(cmd | PORT_CMD_ICC_ACTIVE, port_mmio + PORT_CMD);

}



static void ahci_power_down(void __iomem *port_mmio, u32 cap)

{

	u32 cmd, scontrol;



	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;



	if (cap & HOST_CAP_SSC) {

		/* enable transitions to slumber mode */

		scontrol = readl(port_mmio + PORT_SCR_CTL);

		if ((scontrol & 0x0f00) > 0x100) {

			scontrol &= ~0xf00;

			writel(scontrol, port_mmio + PORT_SCR_CTL);

		}



		/* put device into slumber mode */

		writel(cmd | PORT_CMD_ICC_SLUMBER, port_mmio + PORT_CMD);



		/* wait for the transition to complete */

		ata_wait_register(port_mmio + PORT_CMD, PORT_CMD_ICC_SLUMBER,

				  PORT_CMD_ICC_SLUMBER, 1, 50);

	}



	/* put device into listen mode */

	if (cap & HOST_CAP_SSS) {

		/* first set PxSCTL.DET to 0 */

		scontrol = readl(port_mmio + PORT_SCR_CTL);

		scontrol &= ~0xf;

		writel(scontrol, port_mmio + PORT_SCR_CTL);



		/* then set PxCMD.SUD to 0 */

		cmd &= ~PORT_CMD_SPIN_UP;

		writel(cmd, port_mmio + PORT_CMD);

	}

}



static void ahci_init_port(void __iomem *port_mmio, u32 cap,

			   dma_addr_t cmd_slot_dma, dma_addr_t rx_fis_dma)

{

	/* power up */

	ahci_power_up(port_mmio, cap);



	/* enable FIS reception */

	ahci_start_fis_rx(port_mmio, cap, cmd_slot_dma, rx_fis_dma);



	/* enable DMA */

	ahci_start_engine(port_mmio);

}



static int ahci_deinit_port(void __iomem *port_mmio, u32 cap, const char **emsg)

{

	int rc;



	/* disable DMA */

	rc = ahci_stop_engine(port_mmio);

	if (rc) {

		*emsg = "failed to stop engine";

		return rc;

	}



	/* disable FIS reception */

	rc = ahci_stop_fis_rx(port_mmio);

	if (rc) {

		*emsg = "failed stop FIS RX";

		return rc;

	}



	/* put device into slumber mode */

	ahci_power_down(port_mmio, cap);



	return 0;

}



static unsigned int ahci_dev_classify(struct ata_port *ap)

{

	void __iomem *port_mmio = (void __iomem *) ap->ioaddr.cmd_addr;
@@ -1037,20 +1169,8 @@ static int ahci_port_start(struct ata_port *ap) 


	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_FIS_ADDR);

	readl(port_mmio + PORT_FIS_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 */

	/* initialize port */

	ahci_init_port(port_mmio, hpriv->cap, pp->cmd_slot_dma, pp->rx_fis_dma);



	return 0;

}
@@ -1058,20 +1178,17 @@ static int ahci_port_start(struct ata_port *ap) 
static void ahci_port_stop(struct ata_port *ap)

{

	struct device *dev = ap->host_set->dev;

	struct ahci_host_priv *hpriv = ap->host_set->private_data;

	struct ahci_port_priv *pp = ap->private_data;

	void __iomem *mmio = ap->host_set->mmio_base;

	void __iomem *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 */

	const char *emsg = NULL;

	int rc;



	/* spec says 500 msecs for each PORT_CMD_{START,FIS_RX} bit, so

	 * this is slightly incorrect.

	 */

	msleep(500);

	/* de-initialize port */

	rc = ahci_deinit_port(port_mmio, hpriv->cap, &emsg);

	if (rc)

		ata_port_printk(ap, KERN_WARNING, "%s (%d)\n", emsg, rc);



	ap->private_data = NULL;

	dma_free_coherent(dev, AHCI_PORT_PRIV_DMA_SZ,
@@ -1099,7 +1216,7 @@ static int ahci_host_init(struct ata_probe_ent *probe_ent) 
	struct pci_dev *pdev = to_pci_dev(probe_ent->dev);

	void __iomem *mmio = probe_ent->mmio_base;

	u32 tmp, cap_save;

	unsigned int i, j, using_dac;

	unsigned int i, using_dac;

	int rc;

	void __iomem *port_mmio;
@@ -1175,6 +1292,8 @@ static int ahci_host_init(struct ata_probe_ent *probe_ent) 
	}



	for (i = 0; i < probe_ent->n_ports; i++) {

		const char *emsg = NULL;



#if 0 /* BIOSen initialize this incorrectly */

		if (!(hpriv->port_map & (1 << i)))

			continue;
@@ -1187,43 +1306,24 @@ static int ahci_host_init(struct ata_probe_ent *probe_ent) 
				(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.

			 */

			msleep(500);

		}



		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++;

		}

		rc = ahci_deinit_port(port_mmio, hpriv->cap, &emsg);

		if (rc)

			dev_printk(KERN_WARNING, &pdev->dev,

				   "%s (%d)\n", emsg, rc);



		/* clear SError */

		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 */

		/* clear & turn off port IRQ */

		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);

		writel(0, port_mmio + PORT_IRQ_MASK);

	}



	tmp = readl(mmio + HOST_CTL);

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