[PATCH] libata: check SATA_SETTINGS log with HW Feature Ctrl

[PATCH] libata: check SATA_SETTINGS log with HW Feature Ctrl

[Shane Huang]

NCQ capability was used to check availability of SATA Settings page
from Identify Device Data Log, which contains DevSlp timing variables.
It does not work on some HDDs and leads to error messages.
IDENTIFY word 78 bit 5(Hardware Feature Control) should be used.

Quoting SATA spec 3.1:
If Hardware Feature Control is supported, then:
a) IDENTIFY DEVICE data word 78 bit 5 (see 13.2.1.18) shall be
set to one;
b) the SET FEATURES Select Hardware Feature Control subcommand
shall be supported (see 13.3.8);
c) page 08h of the Identify Device Data log (see 13.7.7) shall
be supported;

This patch is not tested on SATA HDD with DevSlp supported.

Reported-by: Borislav Petkov <bp@amd64.org>
Signed-off-by: Shane Huang <shane.huang@amd.com>
---
 drivers/ata/libata-core.c |    3 +--
 include/linux/ata.h       |    1 +
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 3cc7096..4c9a58b 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2330,9 +2330,8 @@ int ata_dev_configure(struct ata_device *dev)
 
 		/* Obtain SATA Settings page from Identify Device Data Log,
 		 * which contains DevSlp timing variables etc.
-		 * Exclude old devices with ata_id_has_ncq()
 		 */
-		if (ata_id_has_ncq(dev->id)) {
+		if (ata_id_has_hw_feature_ctrl(dev->id)) {
 			err_mask = ata_read_log_page(dev,
 						     ATA_LOG_SATA_ID_DEV_DATA,
 						     ATA_LOG_SATA_SETTINGS,
diff --git a/include/linux/ata.h b/include/linux/ata.h
index 408da95..18cbb93 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -593,6 +593,7 @@ 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)[ATA_ID_SATA_CAPABILITY_2] & (1 << 4))
 #define ata_id_has_devslp(id)	((id)[ATA_ID_FEATURE_SUPP] & (1 << 8))
+#define ata_id_has_hw_feature_ctrl(id)	((id)[ATA_ID_FEATURE_SUPP] & (1 << 5))
 
 static inline bool ata_id_has_hipm(const u16 *id)
 {
-- 
1.7.9.5

Re: [PATCH] libata: check SATA_SETTINGS log with HW Feature Ctrl

[Jeff Garzik]

On 11/17/2012 03:44 PM, Shane Huang wrote:
> NCQ capability was used to check availability of SATA Settings page
> from Identify Device Data Log, which contains DevSlp timing variables.
> It does not work on some HDDs and leads to error messages.
> IDENTIFY word 78 bit 5(Hardware Feature Control) should be used.
>
> Quoting SATA spec 3.1:
> If Hardware Feature Control is supported, then:
> a) IDENTIFY DEVICE data word 78 bit 5 (see 13.2.1.18) shall be
> set to one;
> b) the SET FEATURES Select Hardware Feature Control subcommand
> shall be supported (see 13.3.8);
> c) page 08h of the Identify Device Data log (see 13.7.7) shall
> be supported;
>
> This patch is not tested on SATA HDD with DevSlp supported.
>
> Reported-by: Borislav Petkov <bp@amd64.org>
> Signed-off-by: Shane Huang <shane.huang@amd.com>
> ---
>   drivers/ata/libata-core.c |    3 +--
>   include/linux/ata.h       |    1 +
>   2 files changed, 2 insertions(+), 2 deletions(-)

applied

RE: [PATCH] libata: check SATA_SETTINGS log with HW Feature Ctrl

[Huang, Shane]

Jeff,

> > This patch is not tested on SATA HDD with DevSlp supported.
> >
> > Reported-by: Borislav Petkov <bp@amd64.org>
> > Signed-off-by: Shane Huang <shane.huang@amd.com>
> > ---
> >   drivers/ata/libata-core.c |    3 +--
> >   include/linux/ata.h       |    1 +
> >   2 files changed, 2 insertions(+), 2 deletions(-)
> 
> applied

Please suspend this patch because I just received two new
DevSlp drives but found word 78 bit 5 is _not_ set.

I'm checking with the drive vendor whether he gave me
the wrong information. If bit 5 is not the necessary and
sufficient condition, I will implement another patch to
replace ata_device->sata_settings into ->devslp_timing.

Thanks,
Shane

Re: [PATCH] libata: check SATA_SETTINGS log with HW Feature Ctrl

[Jeff Garzik]

On 12/11/2012 04:25 AM, Huang, Shane wrote:
> Jeff,
>
>>> This patch is not tested on SATA HDD with DevSlp supported.
>>>
>>> Reported-by: Borislav Petkov <bp@amd64.org>
>>> Signed-off-by: Shane Huang <shane.huang@amd.com>
>>> ---
>>>    drivers/ata/libata-core.c |    3 +--
>>>    include/linux/ata.h       |    1 +
>>>    2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> applied
>
> Please suspend this patch because I just received two new
> DevSlp drives but found word 78 bit 5 is _not_ set.
>
> I'm checking with the drive vendor whether he gave me
> the wrong information. If bit 5 is not the necessary and
> sufficient condition, I will implement another patch to
> replace ata_device->sata_settings into ->devslp_timing.

reverted