diff mbox

[v2] ahci: implement aggressive SATA device sleep support

Message ID 1345761072-2123-1-git-send-email-shane.huang@amd.com
State Not Applicable
Delegated to: David Miller
Headers show

Commit Message

Shane Huang Aug. 23, 2012, 10:31 p.m. UTC 
Device Sleep is a feature as described in AHCI 1.3.1 Technical Proposal.
This feature enables an HBA and SATA storage device to enter the DevSleep
interface state, enabling lower power SATA-based systems.

Aggressive Device Sleep enables the HBA to assert the DEVSLP signal as
soon as there are no commands outstanding to the device and the port
specific Device Sleep idle timer has expired. This enables autonomous
entry into the DevSleep interface state without waiting for software
in power sensitive systems.

This patch enables Aggressive Device Sleep only if both host controller
and device support it.

Tested on AMD reference board together with Device Sleep supported device
sample.

Signed-off-by: Shane Huang <shane.huang@amd.com>
Reviewed-by: Aaron Lu <aaron.lwe@gmail.com>
---
Changes from the last version(v1):
* Refine the description and add test information.
* No need to disable DevSlp again if it was already disabled.
* No need to call ata_dev_set_feature() in each DevSlp enablement,
  move it to ata_dev_configure().
* Get MDAT from Identify Device Data Log of the device, if the value
  is zero, then use the nominal value 10ms.
* Get DETO from Identify Device Data Log of the device, if the value
  is zero, then use the nominal value 20ms.

 drivers/ata/ahci.h        |   14 +++++++++
 drivers/ata/libahci.c     |   74 ++++++++++++++++++++++++++++++++++++++++++++-
 drivers/ata/libata-core.c |   29 +++++++++++++++---
 drivers/ata/libata-eh.c   |    4 +--
 drivers/ata/libata.h      |    2 ++
 include/linux/ata.h       |    3 ++
 include/linux/libata.h    |    4 +++
 7 files changed, 122 insertions(+), 8 deletions(-)

Comments

Jeff Garzik Aug. 23, 2012, 3:09 p.m. UTC | #1 
On 08/23/2012 06:31 PM, Shane Huang wrote:
> This patch enables Aggressive Device Sleep only if both host controller
> and device support it.
[...]

> @@ -2323,6 +2324,26 @@ int ata_dev_configure(struct ata_device *dev)
>   			}
>   		}
>
> +		if (ata_id_has_devslp(dev->id)) {
> +			err_mask = ata_dev_set_feature(dev,
> +						       SETFEATURES_SATA_ENABLE,
> +						       SATA_DEVSLP);
> +			if (err_mask)
> +				ata_dev_err(dev,
> +					    "failed to enable DEVSLP (err_mask=0x%x)\n",
> +					    err_mask);
> +			else {
> +				dev->flags |= ATA_DFLAG_DEVSLP;
> +				err_mask = ata_read_log_page(dev,
> +						ATA_LOG_SATA_SETTINGS,
> +						dev->sata_settings,
> +						1);
> +				if (err_mask)
> +					ata_dev_warn(dev,
> +						     "failed to get Identify Device Data\n");
> +			}
> +		}
> +
>   		dev->cdb_len = 16;
>   	}
>

1) Contra the patch description (quoted above), you are enabling 
SATA_DEVSLP on the device regardless of power policy or host controller 
support.

I'm not sure about the ata_dev_configure() change.  If the power policy 
is not enabling aggressive sleep, we should not send this command to the 
device.

2) If we are going to unconditionally add ATA_SECT_SIZE bytes to every 
ata_device structure, let's at least move the ata_read_log_page() call 
outside of the devslp test, so that others may have this information 
even if the device does not support devslp.

3) please define constants in linux/ata.h for sata_settings information, 
rather than using hexidecimal constants ("magic numbers").

4) is it wise to issue SET_FEATURES / SATA_DEVSLP prior to programming 
the host controller?  that order seems wrong.

	Jeff





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Aaron Lu Aug. 24, 2012, 12:49 a.m. UTC | #2 
On 08/23/2012 11:09 PM, Jeff Garzik wrote:
> On 08/23/2012 06:31 PM, Shane Huang wrote:
>> This patch enables Aggressive Device Sleep only if both host controller
>> and device support it.
> [...]
> 
>> @@ -2323,6 +2324,26 @@ int ata_dev_configure(struct ata_device *dev)
>>   			}
>>   		}
>>
>> +		if (ata_id_has_devslp(dev->id)) {
>> +			err_mask = ata_dev_set_feature(dev,
>> +						       SETFEATURES_SATA_ENABLE,
>> +						       SATA_DEVSLP);
>> +			if (err_mask)
>> +				ata_dev_err(dev,
>> +					    "failed to enable DEVSLP (err_mask=0x%x)\n",
>> +					    err_mask);
>> +			else {
>> +				dev->flags |= ATA_DFLAG_DEVSLP;
>> +				err_mask = ata_read_log_page(dev,
>> +						ATA_LOG_SATA_SETTINGS,
>> +						dev->sata_settings,
>> +						1);
>> +				if (err_mask)
>> +					ata_dev_warn(dev,
>> +						     "failed to get Identify Device Data\n");
>> +			}
>> +		}
>> +
>>   		dev->cdb_len = 16;
>>   	}
>>
> 
> 1) Contra the patch description (quoted above), you are enabling 
> SATA_DEVSLP on the device regardless of power policy or host controller 
> support.
> 
> I'm not sure about the ata_dev_configure() change.  If the power policy 
> is not enabling aggressive sleep, we should not send this command to the 
> device.

My understanding is that the devslp link power state will only be
entered when the host asserts the devslp signal(an out of band signal),
this may be done autonomously by the host or manually programmed by
software, while this patch cares about the former one.

The prerequisite for this would be the device's devslp feature being
already enabled, but enabling this feature for the device doesn't mean
the device wants to initiate a link power state transition.

So I think we can simply enable this feature while configuring this
device and the enter/exit of devslp is taken care of by ahci_set_lpm,
does this make sense?

Please correct me if I'm wrong, thanks.

-Aaron
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Shane Huang Aug. 24, 2012, 10:46 a.m. UTC | #3 
Jeff,

> 2) If we are going to unconditionally add ATA_SECT_SIZE bytes to every 
> ata_device structure, let's at least move the ata_read_log_page() call 
> outside of the devslp test, so that others may have this information 
> even if the device does not support devslp.

Agreed, the info in that page is not limited to DevSlp variables.
Should I also move it outside of the ata_dev_configure() function?
Do you have better place to suggest?


> 3) please define constants in linux/ata.h for sata_settings information, 
> rather than using hexidecimal constants ("magic numbers").

OK, I will define ATA_ID_FEATURE_SUPP to replace all the 78.


> 4) is it wise to issue SET_FEATURES / SATA_DEVSLP prior to programming 
> the host controller?  that order seems wrong.

Per our understanding, there is no sequence requirement on this,
please correct me if you see risk.


Thanks,
Shane

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Shane Huang Aug. 24, 2012, 3:18 p.m. UTC | #4 
> OK, I will define ATA_ID_FEATURE_SUPP to replace all the 78.

Oh, I find you were talking about sata_settings information...
I also agree with you and will take your suggestion in v3.


Thanks,
Shane

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Jeff Garzik Aug. 24, 2012, 3:36 p.m. UTC | #5 
On 08/24/2012 06:46 AM, Huang, Shane wrote:
> Jeff,
>
>> 2) If we are going to unconditionally add ATA_SECT_SIZE bytes to every
>> ata_device structure, let's at least move the ata_read_log_page() call
>> outside of the devslp test, so that others may have this information
>> even if the device does not support devslp.
>
> Agreed, the info in that page is not limited to DevSlp variables.
> Should I also move it outside of the ata_dev_configure() function?
> Do you have better place to suggest?

ata_dev_configure() is the proper place.  Just move the log-read outside 
the ata_id_devslp test.

To avoid attempting to enable on older devices, you will need an 
appropriate test (ata_id_has_ncq perhaps?)


>> 3) please define constants in linux/ata.h for sata_settings information,
>> rather than using hexidecimal constants ("magic numbers").
>
> OK, I will define ATA_ID_FEATURE_SUPP to replace all the 78.

As you figured out in the other email, I was referring to sata_settings


>> 4) is it wise to issue SET_FEATURES / SATA_DEVSLP prior to programming
>> the host controller?  that order seems wrong.
>
> Per our understanding, there is no sequence requirement on this,
> please correct me if you see risk.

I just do not like programming the device, when power policy may 
indicate otherwise.

Most conservative is to leave devslp feature in reset state and not 
touch device or host until power policy dictates it is time to program 
host + device.

	Jeff



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Shane Huang Aug. 27, 2012, 10:36 a.m. UTC | #6 
> To avoid attempting to enable on older devices, you will need an 
> appropriate test (ata_id_has_ncq perhaps?)

So far I don't find better method to exclude old devices than yours.


> As you figured out in the other email, I was referring to sata_settings

I'm going to modify both sata_settings and ID[78].


> I just do not like programming the device, when power policy may 
> indicate otherwise.
> 
> Most conservative is to leave devslp feature in reset state and not 
> touch device or host until power policy dictates it is time to program 
> host + device.

OK, I'll move setting feature back to ahci_set_aggressive_devslp().
I'm trying to avoid setting feature each time for every sleep to
improve performance.

Adding pp->device_devslp_enabled with the code below does not make
much difference because it is still called for every sleep.
Do you have good suggestion?

Any should we also call setting feature to disable device DevSlp
for each !sleep?


static void ahci_set_aggressive_devslp(struct ata_port *ap, bool sleep)
{
...
        /* disable device sleep */
        if (!sleep) {
                if (devslp & PORT_DEVSLP_ADSE)
                        writel(devslp & ~PORT_DEVSLP_ADSE,
                               port_mmio + PORT_DEVSLP);
                if (pp->device_devslp_enabled)
                        pp->device_devslp_enabled = false;
                return;
        }
...
        ahci_start_engine(ap);

        /* enable device sleep feature for the drive */
        if (!pp->device_devslp_enabled) {
                err_mask = ata_dev_set_feature(ap->link.device,
                                               SETFEATURES_SATA_ENABLE,
                                               SATA_DEVSLP);
                if (err_mask && err_mask != AC_ERR_DEV)
                        ata_dev_warn(ap->link.device,
                                     "failed to enable DEVSLP, Emask 0x%x\n", err_mask);
                else
                        pp->device_devslp_enabled = true;
        }
}


Thanks,
Shane

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Jeff Garzik Aug. 27, 2012, 4:08 p.m. UTC | #7 
On Mon, Aug 27, 2012 at 6:36 AM, Huang, Shane <Shane.Huang@amd.com> wrote:
>> To avoid attempting to enable on older devices, you will need an
>> appropriate test (ata_id_has_ncq perhaps?)
>
> So far I don't find better method to exclude old devices than yours.
>
>
>> As you figured out in the other email, I was referring to sata_settings
>
> I'm going to modify both sata_settings and ID[78].

Sounds good.


>> I just do not like programming the device, when power policy may
>> indicate otherwise.
>>
>> Most conservative is to leave devslp feature in reset state and not
>> touch device or host until power policy dictates it is time to program
>> host + device.
>
> OK, I'll move setting feature back to ahci_set_aggressive_devslp().
> I'm trying to avoid setting feature each time for every sleep to
> improve performance.
>
> Adding pp->device_devslp_enabled with the code below does not make
> much difference because it is still called for every sleep.
> Do you have good suggestion?
>
> Any should we also call setting feature to disable device DevSlp
> for each !sleep?

Well we want to issue the ATA command to the device at each -power
policy- transition, not for each aggressive sleep.

     Jeff
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diff mbox

Patch

diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index c2594dd..7b6fcf7 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -115,6 +115,9 @@  enum {
 	HOST_CAP2_BOH		= (1 << 0),  /* BIOS/OS handoff supported */
 	HOST_CAP2_NVMHCI	= (1 << 1),  /* NVMHCI supported */
 	HOST_CAP2_APST		= (1 << 2),  /* Automatic partial to slumber */
+	HOST_CAP2_SDS		= (1 << 3),  /* Support device sleep */
+	HOST_CAP2_SADM		= (1 << 4),  /* Support aggressive DevSlp */
+	HOST_CAP2_DESO		= (1 << 5),  /* DevSlp from slumber only */
 
 	/* registers for each SATA port */
 	PORT_LST_ADDR		= 0x00, /* command list DMA addr */
@@ -133,6 +136,7 @@  enum {
 	PORT_SCR_ACT		= 0x34, /* SATA phy register: SActive */
 	PORT_SCR_NTF		= 0x3c, /* SATA phy register: SNotification */
 	PORT_FBS		= 0x40, /* FIS-based Switching */
+	PORT_DEVSLP		= 0x44, /* device sleep */
 
 	/* PORT_IRQ_{STAT,MASK} bits */
 	PORT_IRQ_COLD_PRES	= (1 << 31), /* cold presence detect */
@@ -186,6 +190,7 @@  enum {
 	PORT_CMD_ICC_PARTIAL	= (0x2 << 28), /* Put i/f in partial state */
 	PORT_CMD_ICC_SLUMBER	= (0x6 << 28), /* Put i/f in slumber state */
 
+	/* PORT_FBS bits */
 	PORT_FBS_DWE_OFFSET	= 16, /* FBS device with error offset */
 	PORT_FBS_ADO_OFFSET	= 12, /* FBS active dev optimization offset */
 	PORT_FBS_DEV_OFFSET	= 8,  /* FBS device to issue offset */
@@ -194,6 +199,15 @@  enum {
 	PORT_FBS_DEC		= (1 << 1), /* FBS device error clear */
 	PORT_FBS_EN		= (1 << 0), /* Enable FBS */
 
+	/* PORT_DEVSLP bits */
+	PORT_DEVSLP_DM_OFFSET	= 25,             /* DITO multiplier offset */
+	PORT_DEVSLP_DM_MASK	= (0xf << 25),    /* DITO multiplier mask */
+	PORT_DEVSLP_DITO_OFFSET	= 15,             /* DITO offset */
+	PORT_DEVSLP_MDAT_OFFSET	= 10,             /* Minimum assertion time */
+	PORT_DEVSLP_DETO_OFFSET	= 2,              /* DevSlp exit timeout */
+	PORT_DEVSLP_DSP		= (1 << 1),       /* DevSlp present */
+	PORT_DEVSLP_ADSE	= (1 << 0),       /* Aggressive DevSlp enable */
+
 	/* hpriv->flags bits */
 
 #define AHCI_HFLAGS(flags)		.private_data	= (void *)(flags)
diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index f9eaa82..eddc789 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -76,6 +76,7 @@  static void ahci_qc_prep(struct ata_queued_cmd *qc);
 static int ahci_pmp_qc_defer(struct ata_queued_cmd *qc);
 static void ahci_freeze(struct ata_port *ap);
 static void ahci_thaw(struct ata_port *ap);
+static void ahci_set_aggressive_devslp(struct ata_port *ap, bool sleep);
 static void ahci_enable_fbs(struct ata_port *ap);
 static void ahci_disable_fbs(struct ata_port *ap);
 static void ahci_pmp_attach(struct ata_port *ap);
@@ -193,6 +194,10 @@  module_param(ahci_em_messages, int, 0444);
 MODULE_PARM_DESC(ahci_em_messages,
 	"AHCI Enclosure Management Message control (0 = off, 1 = on)");
 
+int devslp_idle_timeout = 1000;	/* device sleep idle timeout in ms */
+module_param(devslp_idle_timeout, int, 0644);
+MODULE_PARM_DESC(devslp_idle_timeout, "device sleep idle timeout");
+
 static void ahci_enable_ahci(void __iomem *mmio)
 {
 	int i;
@@ -702,6 +707,16 @@  static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
 		}
 	}
 
+	/* set aggressive device sleep */
+	if ((hpriv->cap2 & HOST_CAP2_SDS) &&
+	    (hpriv->cap2 & HOST_CAP2_SADM) &&
+	    (link->device->flags & ATA_DFLAG_DEVSLP)) {
+		if (policy == ATA_LPM_MIN_POWER)
+			ahci_set_aggressive_devslp(ap, true);
+		else
+			ahci_set_aggressive_devslp(ap, false);
+	}
+
 	if (policy == ATA_LPM_MAX_POWER) {
 		sata_link_scr_lpm(link, policy, false);
 
@@ -1889,6 +1904,59 @@  static void ahci_post_internal_cmd(struct ata_queued_cmd *qc)
 		ahci_kick_engine(ap);
 }
 
+static void ahci_set_aggressive_devslp(struct ata_port *ap, bool sleep)
+{
+	void __iomem *port_mmio = ahci_port_base(ap);
+	u32 devslp, dm, dito, mdat, deto;
+	int rc;
+
+	devslp = readl(port_mmio + PORT_DEVSLP);
+	if (!(devslp & PORT_DEVSLP_DSP)) {
+		dev_err(ap->host->dev, "port does not support device sleep\n");
+		return;
+	}
+
+	/* disable device sleep */
+	if (!sleep) {
+		if (devslp & PORT_DEVSLP_ADSE)
+			writel(devslp & ~PORT_DEVSLP_ADSE,
+			       port_mmio + PORT_DEVSLP);
+		return;
+	}
+
+	/* device sleep was already enabled */
+	if (devslp & PORT_DEVSLP_ADSE)
+		return;
+
+	/* set DITO, MDAT, DETO and enable DevSlp, need to stop engine first */
+	rc = ahci_stop_engine(ap);
+	if (rc)
+		return;
+
+	dm = (devslp & PORT_DEVSLP_DM_MASK) >> PORT_DEVSLP_DM_OFFSET;
+	dito = devslp_idle_timeout / (dm + 1);
+	if (dito > 0x3ff)
+		dito = 0x3ff;
+
+	/* If the value in MDAT is zero, then use 10 ms as the value of MDAT */
+	mdat = (ap->link.device->sata_settings[0x30]) & 0x1f;
+	if (!mdat)
+		mdat = 10;
+
+	/* If the value in DETO is zero, then use 20 ms as the value of DETO */
+	deto = ap->link.device->sata_settings[0x31];
+	if (!deto)
+		deto = 20;
+
+	devslp |= ((dito << PORT_DEVSLP_DITO_OFFSET) |
+		   (mdat << PORT_DEVSLP_MDAT_OFFSET) |
+		   (deto << PORT_DEVSLP_DETO_OFFSET) |
+		   PORT_DEVSLP_ADSE);
+	writel(devslp, port_mmio + PORT_DEVSLP);
+
+	ahci_start_engine(ap);
+}
+
 static void ahci_enable_fbs(struct ata_port *ap)
 {
 	struct ahci_port_priv *pp = ap->private_data;
@@ -2163,7 +2231,8 @@  void ahci_print_info(struct ata_host *host, const char *scc_s)
 		"flags: "
 		"%s%s%s%s%s%s%s"
 		"%s%s%s%s%s%s%s"
-		"%s%s%s%s%s%s\n"
+		"%s%s%s%s%s%s%s"
+		"%s%s\n"
 		,
 
 		cap & HOST_CAP_64 ? "64bit " : "",
@@ -2183,6 +2252,9 @@  void ahci_print_info(struct ata_host *host, const char *scc_s)
 		cap & HOST_CAP_CCC ? "ccc " : "",
 		cap & HOST_CAP_EMS ? "ems " : "",
 		cap & HOST_CAP_SXS ? "sxs " : "",
+		cap2 & HOST_CAP2_DESO ? "deso " : "",
+		cap2 & HOST_CAP2_SADM ? "sadm " : "",
+		cap2 & HOST_CAP2_SDS ? "sds " : "",
 		cap2 & HOST_CAP2_APST ? "apst " : "",
 		cap2 & HOST_CAP2_NVMHCI ? "nvmp " : "",
 		cap2 & HOST_CAP2_BOH ? "boh " : ""
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index fadd586..9754b53 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2155,6 +2155,7 @@  int ata_dev_configure(struct ata_device *dev)
 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
 	const u16 *id = dev->id;
 	unsigned long xfer_mask;
+	unsigned int err_mask;
 	char revbuf[7];		/* XYZ-99\0 */
 	char fwrevbuf[ATA_ID_FW_REV_LEN+1];
 	char modelbuf[ATA_ID_PROD_LEN+1];
@@ -2323,6 +2324,26 @@  int ata_dev_configure(struct ata_device *dev)
 			}
 		}
 
+		if (ata_id_has_devslp(dev->id)) {
+			err_mask = ata_dev_set_feature(dev,
+						       SETFEATURES_SATA_ENABLE,
+						       SATA_DEVSLP);
+			if (err_mask)
+				ata_dev_err(dev,
+					    "failed to enable DEVSLP (err_mask=0x%x)\n",
+					    err_mask);
+			else {
+				dev->flags |= ATA_DFLAG_DEVSLP;
+				err_mask = ata_read_log_page(dev,
+						ATA_LOG_SATA_SETTINGS,
+						dev->sata_settings,
+						1);
+				if (err_mask)
+					ata_dev_warn(dev,
+						     "failed to get Identify Device Data\n");
+			}
+		}
+
 		dev->cdb_len = 16;
 	}
 
@@ -2351,8 +2372,6 @@  int ata_dev_configure(struct ata_device *dev)
 		    (ap->flags & ATA_FLAG_AN) && ata_id_has_atapi_AN(id) &&
 		    (!sata_pmp_attached(ap) ||
 		     sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf) == 0)) {
-			unsigned int err_mask;
-
 			/* issue SET feature command to turn this on */
 			err_mask = ata_dev_set_feature(dev,
 					SETFEATURES_SATA_ENABLE, SATA_AN);
@@ -3598,7 +3617,7 @@  int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
 	switch (policy) {
 	case ATA_LPM_MAX_POWER:
 		/* disable all LPM transitions */
-		scontrol |= (0x3 << 8);
+		scontrol |= (0x7 << 8);
 		/* initiate transition to active state */
 		if (spm_wakeup) {
 			scontrol |= (0x4 << 12);
@@ -3608,12 +3627,12 @@  int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
 	case ATA_LPM_MED_POWER:
 		/* allow LPM to PARTIAL */
 		scontrol &= ~(0x1 << 8);
-		scontrol |= (0x2 << 8);
+		scontrol |= (0x6 << 8);
 		break;
 	case ATA_LPM_MIN_POWER:
 		if (ata_link_nr_enabled(link) > 0)
 			/* no restrictions on LPM transitions */
-			scontrol &= ~(0x3 << 8);
+			scontrol &= ~(0x7 << 8);
 		else {
 			/* empty port, power off */
 			scontrol &= ~0xf;
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 7d4535e..ed0a120 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -1499,8 +1499,8 @@  static const char *ata_err_string(unsigned int err_mask)
  *	RETURNS:
  *	0 on success, AC_ERR_* mask otherwise.
  */
-static unsigned int ata_read_log_page(struct ata_device *dev,
-				      u8 page, void *buf, unsigned int sectors)
+unsigned int ata_read_log_page(struct ata_device *dev,
+			       u8 page, void *buf, unsigned int sectors)
 {
 	struct ata_taskfile tf;
 	unsigned int err_mask;
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 50e4dff..be14f1e 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -165,6 +165,8 @@  extern void ata_eh_about_to_do(struct ata_link *link, struct ata_device *dev,
 			       unsigned int action);
 extern void ata_eh_done(struct ata_link *link, struct ata_device *dev,
 			unsigned int action);
+extern unsigned int ata_read_log_page(struct ata_device *dev,
+				      u8 page, void *buf, unsigned int sectors);
 extern void ata_eh_autopsy(struct ata_port *ap);
 const char *ata_get_cmd_descript(u8 command);
 extern void ata_eh_report(struct ata_port *ap);
diff --git a/include/linux/ata.h b/include/linux/ata.h
index 5713d3a..931bf08 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -292,6 +292,7 @@  enum {
 
 	/* READ_LOG_EXT pages */
 	ATA_LOG_SATA_NCQ	= 0x10,
+	ATA_LOG_SATA_SETTINGS	= 0x38,
 
 	/* READ/WRITE LONG (obsolete) */
 	ATA_CMD_READ_LONG	= 0x22,
@@ -345,6 +346,7 @@  enum {
 	SATA_FPDMA_IN_ORDER	= 0x04,	/* FPDMA in-order data delivery */
 	SATA_AN			= 0x05,	/* Asynchronous Notification */
 	SATA_SSP		= 0x06,	/* Software Settings Preservation */
+	SATA_DEVSLP		= 0x09,	/* Device Sleep */
 
 	/* feature values for SET_MAX */
 	ATA_SET_MAX_ADDR	= 0x00,
@@ -579,6 +581,7 @@  static inline int ata_is_data(u8 prot)
 
 #define ata_id_cdb_intr(id)	(((id)[ATA_ID_CONFIG] & 0x60) == 0x20)
 #define ata_id_has_da(id)	((id)[77] & (1 << 4))
+#define ata_id_has_devslp(id)	((id)[78] & (1 << 8))
 
 static inline bool ata_id_has_hipm(const u16 *id)
 {
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 64f90e1..464e67c 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -162,6 +162,7 @@  enum {
 	ATA_DFLAG_DETACHED	= (1 << 25),
 
 	ATA_DFLAG_DA		= (1 << 26), /* device supports Device Attention */
+	ATA_DFLAG_DEVSLP	= (1 << 27), /* device supports Device Sleep */
 
 	ATA_DEV_UNKNOWN		= 0,	/* unknown device */
 	ATA_DEV_ATA		= 1,	/* ATA device */
@@ -649,6 +650,9 @@  struct ata_device {
 		u32		gscr[SATA_PMP_GSCR_DWORDS]; /* PMP GSCR block */
 	};
 
+	/* Identify Device Data Log (30h), SATA Settings (page 08h) */
+	u8			sata_settings[ATA_SECT_SIZE];
+
 	/* error history */
 	int			spdn_cnt;
 	/* ering is CLEAR_END, read comment above CLEAR_END */