[MtFuji] SATA AN, Sleep power state and media arrival notification

keiji_katata at post.pioneer.co.jp keiji_katata at post.pioneer.co.jp
Tue Nov 25 23:00:12 PST 2008


* From the T10 Reflector (t10 at t10.org), posted by:
* keiji_katata at post.pioneer.co.jp
*
Hello David,
>The first set of questions is regarding the entry to sleep mode. Should a
>power state notification be generated?
Basically No. At the completion of the START/STOP UNIT command for the sleep,
drive should enter the sleep state, then host should use Hard Reset (SSP=1)
to
communicate with the drive again. You may refer page 502 of Fuji7 R111.
In the case of native queuing environment when GESN is queued, before
completion
of the START/STOP UNIT command for sleep, the queued GESN shall be executed
and
shall be finished. In this case, a power state notification will be
generated.
I think your understanding is correct. Sleep option of START/STOP UNIT
command
is designed to turn off the drive power by host. Many drives may have same
power
consumption on Standby and on Sleep. If you want less power consumption than
now, you may request lower power consumption of Standby mode.
Or host may actually remove the power from drive. This case door of the drive
will not open.
Best regards,
Keiji Katata
PIONEER CORP.
David Burg <daviburg at windows.microsoft.com>@avc-pioneer.com on 2008/11/21
18:22:46
mtfuji5 at avc-pioneer.com$B$KJV?.$7$F$/$@$5$$(B
$BAw?.<T(B:	  owner-mtfuji5 at avc-pioneer.com
$B08 at h(B:  "t10 at t10.org" <t10 at t10.org>, "mtfuji5 at avc-pioneer.com"
       <mtfuji5 at avc-pioneer.com>
cc:    Michael Xing <xiaoxing at microsoft.com>, Frank Shu
       <frankshu at windows.microsoft.com>, David Walp
<David.Walp at microsoft.com>,
       Ope Aladekomo <Ope.Aladekomo at microsoft.com>
$B7oL>(B:  [MtFuji] SATA AN, Sleep power state and media arrival
notification
Hi,
In a conference call with a SATA chipset manufacturer earlier this week the
manufacturer expressed difficulties in the implementation of SATA
Asynchronous
Notification (AN) because of the perceived lack of clarity in the handling of
sleep mode in combination with AN. As the manufacturer is not present on this
reflector or the Mt Fuji committee, I am relaying their issue. However the
chipset manufacturer is working with device manufacturer(s) from Mt Fuji
committee and expect that member(s) will be familiar and supportive of the
issue
resolution.
The chipset manufacturer is not clear what is the specified device behavior
when
the host issues a START/STOP UNIT command with parameters to request sleep
mode.
The first set of questions is regarding the entry to sleep mode. Should a
power
state notification be generated? If a power state notification is generated,
should AN be set? If a notification is generated and AN is set, will the
device
complete GESN from the host despite been in sleep mode? Does setting the
immediate bit change the behavior of event notification?
The second set of questions is regarding notification while in sleep mode. In
sleep mode, can the user insert an optical media? If the user can, can the
device generate a media arrival event? If so, can AN be posted and will the
device complete GESN from the host despite been in sleep mode?
If the user can insert a media but the device cannot generate a media arrival
event, the manufacturer is concerned by the user experience.
If the user cannot insert a media ? for instance if the device is actually
powered off in sleep and the door won$B!G(Bt open ? can PC vendors really
use this
mode for power saving without affecting the user experience?
Microsoft$B!G(Bs (not speaking on the manufacturer$B!G(Bs behalf now)
understanding of the
current Mt Fuji specification is that no event is generated *after* entering
sleep mode. So if the host issues a START/STOP UNIT command with parameters
to
request sleep mode with immediate bit set, the command completes, no event is
generated and no command but reset will work after the START/STOP UNIT
command
completes.
But if the host issues a START/STOP UNIT command with parameters to request
sleep mode with immediate bit NOT set, the command completes right away, no
power event is posted BUT if a GESN command is still processed while entering
sleep mode, Power Status Field is set to $B!H(B4h ? Sleep ? The device is
about to
enter sleep state$B!I(B, and AN is not set.
Microsoft$B!G(Bs understanding of the device sleep power mode is that it
should be
used only if the host itself (sleeps or) hibernates or powers off. Device
sleep
power mode should not be used while the host system is active, even if there
is
no optical device activity, because user interaction with the device would
not
work in sleep power mode (such as opening / closing the tray, inserting &
detection a new media). Instead, standby power mode needs to be used when the
host is active but the device is waiting.
Chipset manufacturer measured however that there is a non-negligible power
consumption saving by entering sleep mode in comparison to standby mode.
Could the device manufacturers on the reflector help clarify the source of
the
power consumption in standby mode. What could we do to avoid this power
consumption but still preserve the user experience of opening/closing door
and
detecting inserted media?
With regards,
David Burg.
*
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