libata: Add ALPM power state accounting to the AHCI driver

Message ID	20091113192429.4dfc9c39@infradead.org
State	Not Applicable
Delegated to:	David Miller
Headers	show Return-Path: <linux-ide-owner@vger.kernel.org> Date: Fri, 13 Nov 2009 19:24:29 -0800 From: Arjan van de Ven <arjan@infradead.org> To: linux-ide@vger.kernel.org, Jeff Garzik <jgarzik@pobox.com>, Tejun Heo <tj@kernel.org> Cc: akpm@linux-foundation.org Subject: [PATCH] libata: Add ALPM power state accounting to the AHCI driver Message-ID: <20091113192429.4dfc9c39@infradead.org> Organization: Intel Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Sender: linux-ide-owner@vger.kernel.org Precedence: bulk

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index a3241a1..448d684 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -72,6 +72,21 @@ MODULE_PARM_DESC(ignore_sss, "Ignore staggered spinup flag (0=don't ignore, 1=ig static int ahci_enable_alpm(struct ata_port *ap, enum link_pm policy); static void ahci_disable_alpm(struct ata_port *ap); + +static ssize_t ahci_alpm_show_active(struct device *dev, + struct device_attribute *attr, char *buf); +static ssize_t ahci_alpm_show_slumber(struct device *dev, + struct device_attribute *attr, char *buf); +static ssize_t ahci_alpm_show_partial(struct device *dev, + struct device_attribute *attr, char *buf); + +static ssize_t ahci_alpm_show_accounting(struct device *dev, + struct device_attribute *attr, char *buf); + +static ssize_t ahci_alpm_set_accounting(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count); + static ssize_t ahci_led_show(struct ata_port *ap, char *buf); static ssize_t ahci_led_store(struct ata_port *ap, const char *buf, size_t size); @@ -289,6 +304,13 @@ struct ahci_host_priv { u32 em_loc; /* enclosure management location */ }; +enum ahci_port_states { + AHCI_PORT_NOLINK = 0, + AHCI_PORT_ACTIVE = 1, + AHCI_PORT_PARTIAL = 2, + AHCI_PORT_SLUMBER = 3 +}; + struct ahci_port_priv { struct ata_link *active_link; struct ahci_cmd_hdr *cmd_slot; @@ -304,6 +326,14 @@ struct ahci_port_priv { u32 intr_mask; /* interrupts to enable */ /* enclosure management info per PM slot */ struct ahci_em_priv em_priv[EM_MAX_SLOTS]; + + /* ALPM accounting state and stats */ + unsigned int accounting_active:1; + u64 active_jiffies; + u64 partial_jiffies; + u64 slumber_jiffies; + int previous_state; + int previous_jiffies; }; static int ahci_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val); @@ -359,6 +389,12 @@ DEVICE_ATTR(ahci_host_cap2, S_IRUGO, ahci_show_host_cap2, NULL); DEVICE_ATTR(ahci_host_version, S_IRUGO, ahci_show_host_version, NULL); DEVICE_ATTR(ahci_port_cmd, S_IRUGO, ahci_show_port_cmd, NULL); +DEVICE_ATTR(ahci_alpm_active, S_IRUGO, ahci_alpm_show_active, NULL); +DEVICE_ATTR(ahci_alpm_partial, S_IRUGO, ahci_alpm_show_partial, NULL); +DEVICE_ATTR(ahci_alpm_slumber, S_IRUGO, ahci_alpm_show_slumber, NULL); +DEVICE_ATTR(ahci_alpm_accounting, S_IRUGO | S_IWUSR, + ahci_alpm_show_accounting, ahci_alpm_set_accounting); + static struct device_attribute *ahci_shost_attrs[] = { &dev_attr_link_power_management_policy, &dev_attr_em_message_type, @@ -367,6 +403,10 @@ static struct device_attribute *ahci_shost_attrs[] = { &dev_attr_ahci_host_cap2, &dev_attr_ahci_host_version, &dev_attr_ahci_port_cmd, + &dev_attr_ahci_alpm_active, + &dev_attr_ahci_alpm_partial, + &dev_attr_ahci_alpm_slumber, + &dev_attr_ahci_alpm_accounting, NULL }; @@ -1165,9 +1205,14 @@ static int ahci_enable_alpm(struct ata_port *ap, * getting woken up due to spurious phy ready interrupts * TBD - Hot plug should be done via polling now, is * that even supported? + * + * However, when accounting_active is set, we do want + * the interrupts for accounting purposes. */ - pp->intr_mask &= ~PORT_IRQ_PHYRDY; - writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK); + if (!pp->accounting_active) { + pp->intr_mask &= ~PORT_IRQ_PHYRDY; + writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK); + } /* * Set a flag to indicate that we should ignore all PhyRdy @@ -2157,6 +2202,131 @@ static void ahci_error_intr(struct ata_port *ap, u32 irq_stat) ata_port_abort(ap); } +static int get_current_alpm_state(struct ata_port *ap) +{ + u32 status = 0; + + ahci_scr_read(&ap->link, SCR_STATUS, &status); + + /* link status is in bits 11-8 */ + status = status >> 8; + status = status & 0x7; + + if (status == 6) + return AHCI_PORT_SLUMBER; + if (status == 2) + return AHCI_PORT_PARTIAL; + if (status == 1) + return AHCI_PORT_ACTIVE; + return AHCI_PORT_NOLINK; +} + +static void account_alpm_stats(struct ata_port *ap) +{ + struct ahci_port_priv *pp = ap->private_data; + + int new_state; + u64 new_jiffies, jiffies_delta; + + new_state = get_current_alpm_state(ap); + new_jiffies = jiffies; + + jiffies_delta = new_jiffies - pp->previous_jiffies; + + switch (pp->previous_state) { + case AHCI_PORT_NOLINK: + pp->active_jiffies = 0; + pp->partial_jiffies = 0; + pp->slumber_jiffies = 0; + break; + case AHCI_PORT_ACTIVE: + pp->active_jiffies += jiffies_delta; + break; + case AHCI_PORT_PARTIAL: + pp->partial_jiffies += jiffies_delta; + break; + case AHCI_PORT_SLUMBER: + pp->slumber_jiffies += jiffies_delta; + break; + default: + break; + } + pp->previous_state = new_state; + pp->previous_jiffies = new_jiffies; +} + +static ssize_t ahci_alpm_show_active(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct Scsi_Host *shost = class_to_shost(dev); + struct ata_port *ap = ata_shost_to_port(shost); + struct ahci_port_priv *pp = ap->private_data; + + account_alpm_stats(ap); + + return sprintf(buf, "%u\n", jiffies_to_msecs(pp->active_jiffies)); +} + +static ssize_t ahci_alpm_show_partial(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct Scsi_Host *shost = class_to_shost(dev); + struct ata_port *ap = ata_shost_to_port(shost); + struct ahci_port_priv *pp = ap->private_data; + + account_alpm_stats(ap); + + return sprintf(buf, "%u\n", jiffies_to_msecs(pp->partial_jiffies)); +} + +static ssize_t ahci_alpm_show_slumber(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct Scsi_Host *shost = class_to_shost(dev); + struct ata_port *ap = ata_shost_to_port(shost); + struct ahci_port_priv *pp = ap->private_data; + + account_alpm_stats(ap); + + return sprintf(buf, "%u\n", jiffies_to_msecs(pp->slumber_jiffies)); +} + + +static ssize_t ahci_alpm_show_accounting(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct Scsi_Host *shost = class_to_shost(dev); + struct ata_port *ap = ata_shost_to_port(shost); + struct ahci_port_priv *pp = ap->private_data; + + return sprintf(buf, "%u\n", pp->accounting_active); +} + +static ssize_t ahci_alpm_set_accounting(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + unsigned long flags; + struct Scsi_Host *shost = class_to_shost(dev); + struct ata_port *ap = ata_shost_to_port(shost); + struct ahci_port_priv *pp = ap->private_data; + void __iomem *port_mmio = ahci_port_base(ap); + + if (buf[0] == '0') + pp->accounting_active = 0; + if (buf[0] == '1') + pp->accounting_active = 1; + + /* we need to enable the PHYRDY interrupt when we want accounting */ + if (pp->accounting_active) { + spin_lock_irqsave(ap->lock, flags); + pp->intr_mask |= PORT_IRQ_PHYRDY; + writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK); + spin_unlock_irqrestore(ap->lock, flags); + } + return count; +} + static void ahci_port_intr(struct ata_port *ap) { void __iomem *port_mmio = ahci_port_base(ap); @@ -2182,6 +2352,7 @@ static void ahci_port_intr(struct ata_port *ap) if ((hpriv->flags & AHCI_HFLAG_NO_HOTPLUG) && (status & PORT_IRQ_PHYRDY)) { status &= ~PORT_IRQ_PHYRDY; + account_alpm_stats(ap); ahci_scr_write(&ap->link, SCR_ERROR, ((1 << 16) | (1 << 18))); }

libata: Add ALPM power state accounting to the AHCI driver

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