U.S. patent application number 14/333780 was filed with the patent office on 2015-01-22 for appliances powered over sas.
The applicant listed for this patent is LSI Corporation. Invention is credited to Mohamad H. El-Batal, Greg Shogan, Jason M. Stuhlsatz.
Application Number | 20150026503 14/333780 |
Document ID | / |
Family ID | 52344601 |
Filed Date | 2015-01-22 |
United States Patent
Application |
20150026503 |
Kind Code |
A1 |
El-Batal; Mohamad H. ; et
al. |
January 22, 2015 |
APPLIANCES POWERED OVER SAS
Abstract
Methods and structure for powering storage devices over a SAS
interface. An exemplary system includes a storage device that
includes a receptacle configured to receive a plug that
communicates Serial Attached Small Computer Systems Interface
compliant signals from a host system. The storage device also
includes a microcontroller configured to detect a first power level
on a power contact of the receptacle. The storage device further
includes a circuit board configured to power up to the first power
level via the microcontroller, to receive an inter-integrated
circuit communication that indicates a second power level is
available, and to power up to the second power level to
sufficiently power a storage appliance.
Inventors: |
El-Batal; Mohamad H.;
(Boulder, CO) ; Stuhlsatz; Jason M.; (Norcross,
GA) ; Shogan; Greg; (Round Rock, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LSI Corporation |
San Jose |
CA |
US |
|
|
Family ID: |
52344601 |
Appl. No.: |
14/333780 |
Filed: |
July 17, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61847184 |
Jul 17, 2013 |
|
|
|
Current U.S.
Class: |
713/340 |
Current CPC
Class: |
Y02D 10/154 20180101;
G06F 3/0625 20130101; Y02D 10/00 20180101; G06F 3/0689 20130101;
G06F 3/0634 20130101; G06F 3/067 20130101; G11B 33/123
20130101 |
Class at
Publication: |
713/340 |
International
Class: |
G06F 1/26 20060101
G06F001/26 |
Claims
1. A storage device, comprising: a receptacle configured to receive
a plug that communicates Serial Attached Small Computer Systems
Interface compliant signals from a host system; a microcontroller
configured to detect a first power level on a power contact of the
receptacle; and a circuit board configured to power up to the first
power level via the microcontroller, to receive an inter-integrated
circuit communication that indicates a second power level is
available, and to power up to the second power level to
sufficiently power a storage appliance.
2. The storage device of claim 1, wherein: the inter-integrated
circuit communication indicates that up to 30 watts is available
from the host system.
3. The storage device of claim 1, wherein: the plug comprises a
High Density Mini Serial Attached Small Computer System Interface
plug.
4. The storage device of claim 1, wherein: the receptacle comprises
a High Density Mini Serial Attached Small Computer System Interface
plug.
5. The storage device of claim 4, wherein: power is received on
pins B1 and D1 of the receptacle.
6. The storage device of claim 4, wherein: the inter-integrated
circuit communication is received via pins C1 and C2 of the
receptacle.
7. The storage device of claim 1, wherein: the plug is a terminal
end of a size 24 American Wire Gauge standard cable; and the cable
delivers up to 25 watts of power from the host system to the
storage device to power the storage device from a distance of up to
60 meters.
8. A method, comprising: receiving, with a receptacle of a storage
device, a plug that communicates Serial Attached Small Computer
Systems Interface compliant signals from a host system; detecting,
with a microcontroller, a first power level on a power contact of
the receptacle; powering up a circuit board of the storage device
to the first power level via the microcontroller; receiving an
inter-integrated circuit communication that indicates a second
power level is available; and powering-up the circuit board to the
second power level to sufficiently power a storage appliance.
9. The method of claim 8, wherein: the inter-integrated circuit
communication indicates that up to 30 watts is available from the
host system.
10. The method of claim 8, wherein: the plug comprises a High
Density Mini Serial Attached Small Computer System Interface
plug.
11. The method of claim 8, wherein: the receptacle comprises a High
Density Mini Serial Attached Small Computer System Interface
plug.
12. The method of claim 11, wherein: power is received on pins B1
and D1 of the receptacle.
13. The method of claim 11, wherein: the inter-integrated circuit
communication is received via pins C1 and C2 of the receptacle.
14. The method of claim 8, wherein: the plug is a terminal end of a
size 24 American Wire Gauge standard cable; and the cable delivers
up to 25 watts of power from the host system to the storage device
to power the storage device from a distance of up to 60 meters.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This document claims priority to, and thus the benefit of an
earlier filing date from, U.S. Provisional Application No.
61/847,184 (filed on Jul. 17, 2013) entitled "APPLIANCES POWERED
OVER ETHERNET AND SAS", which is hereby incorporated by reference.
This patent application is also related to commonly owned and
co-pending patent application `TBD (Attorney Docket No. 13-0856;
hereinafter the "related patent application"), the contents of
which are incorporated by reference.
FIELD OF THE INVENTION
[0002] The invention generally relates to Serial Attached Small
Computer System Interface (SAS) and, more particularly, to a
storage device that operates on power derived from a SAS
interface.
BACKGROUND
[0003] The Power Over Ethernet (POE) standard, described in IEEE
standards 802.3af and 802.3at, was originally designed and
envisioned to power-up small consumer based terminals and
office/home computing devices. POE enables a single cable to
provide both data connection and electrical power to devices that
use Internet Protocol (IP) connectivity. However POE requires
Ethernet or SCSI over IP (iSCSI) interfaces which are not suited
for certain systems such as storage servers.
SUMMARY
[0004] Systems and methods herein provide for powering devices over
a SAS interface. In one embodiment, a storage device includes a
receptacle configured to receive a plug that communicates Serial
Attached Small Computer Systems Interface compliant signals from a
host system. The storage device also includes a microcontroller
configured to detect a first power level on a power contact of the
receptacle. The storage device further includes a circuit board
configured to power up to the first power level via the
microcontroller, to receive an inter-integrated circuit
communication that indicates a second power level is available, and
to power up to the second power level to sufficiently power a
storage appliance.
[0005] Other exemplary embodiments (e.g., methods and computer
readable media relating to the foregoing embodiments) are also
described below.
BRIEF DESCRIPTION OF THE FIGURES
[0006] Some embodiments of the present invention are now described,
by way of example only, and with reference to the accompanying
figures. The same reference number represents the same element or
the same type of element on all figures.
[0007] FIG. 1 is a block diagram illustrating a SAS topology in an
exemplary embodiment.
[0008] FIGS. 2a-b illustrate views of a connector receptacle and
plug, respectively, operable with a SAS topology.
[0009] FIG. 3 is a power-wire connecting diagram in an exemplary
embodiment.
[0010] FIG. 4 is a flowchart illustrating a method for powering a
storage device over a SAS interface in an exemplary embodiment.
[0011] FIG. 5 is a block diagram of an exemplary computing system
in which a computer readable medium provides instructions for
performing methods therein.
DETAILED DESCRIPTION
[0012] The figures and the following description illustrate
specific exemplary embodiments of the invention. It will thus be
appreciated that those skilled in the art will be able to devise
various arrangements that, although not explicitly described or
shown herein, embody the principles of the invention and are
included within the scope of the invention. Furthermore, any
examples described herein are intended to aid in understanding the
principles of the invention, and are to be construed as being
without limitation to such specifically recited examples and
conditions. As a result, the invention is not limited to the
specific embodiments or examples described below, but by the claims
and their equivalents.
[0013] FIG. 1 is a block diagram illustrating a SAS topology 100 in
an exemplary embodiment. The SAS topology 100 is used to achieve
reliable, high-speed communication between SAS devices in a
point-to-point architecture. The SAS topology 100 includes a host
system 110 coupled to a storage device 120 via a SAS cable 130. The
host system 110 and the storage device 120 include SAS ports 112
and 122, respectively, which are configured to communicate over the
SAS cable 130 in accordance with the SAS protocol. A controller 114
of the host system 110 is configured to generate SAS command
signals to perform read/write operations on data stored on the
storage device 120.
[0014] In this embodiment, the SAS ports 112 and 122 include
connectors of the SFF-8644 specification, entitled "Mini Multilane
12 Gbs 8/4x Shielded Connector," which is hereby incorporated by
reference in its entirety. In the SFF-8644 specification, the power
pin on the SAS port 112 of the host system 110 may apply power
(i.e., Vact) to the SAS port 122 of the storage device 120.
However, in the SFF-8644 specification, Vact is reserved for active
(e.g., longer length) SAS cables and operates at low voltage and
low power (e.g., up to 1.5 watts). In other words, using a SAS
SFF-8644 connector described in the standard, the host system 110
may power, for example, an optical transceiver using up to 1.5
watts, however, that power level is unable to provide power to
larger periphery appliances such as the storage device 120.
[0015] The SAS topology 100 is therefore enhanced with SAS ports
112 and 122 that connect each end of the SAS cable 130 with an
SFF-8644 connector that is configured to supply sufficient power
(e.g., up to 30 watts) to operate the storage device 120 with power
supplied over the SAS cable 130 from the host system 110. Thus, the
SAS port 112 of the host system 110 is configured to supply data
and power in parallel to the SAS port 122 of the storage device
120. Other solutions which implement power and data in parallel
(i.e., Power Over Ethernet) use protocols (i.e., Ethernet) which
are unsuitable for storage networks.
[0016] The controller 114 of the host system 110 is enhanced to
communicate the power-supplying ability of the host system 110 to
other SAS devices using the inter-integrated circuit (I2C)
communication protocol. Furthermore, the microcontroller 124 of the
storage device 120 is enhanced to receive I2C communication to
determine whether the host system 110 is able to provide sufficient
power to operate the storage device 120 over the SAS cable 130. The
SAS ports 112 and 122 of the SAS topology 100 are therefore
configured to use I2C 132 for communicating power ability and
permission to extend Vact 134 to its full range of power (e.g., up
to 30 watts in the SFF-8644 specification).
[0017] Suppose, for example, that the cable 130 is a size 24
according to the American Wire Gauge (AWG) standard. A connector in
accordance with the SFF-8644 standard provides 0.5 amps per
connector (2 pins) at 30 volts for a total power of 30 watts.
Assuming a 5 watt loss budget at 0.08422 watts/meter, the
configuration described herein is operable to provide up to 25
watts (i.e., 30 watts-5 watts) for up to approximately 60 meters
(i.e., 5/0.08422). Thus, the configuration described is able to
provide power over a SAS (POS) connection (i.e., data and power
over a single SAS cable) and selectively power up/down the storage
device 120 (which may be powered with 25 watts) via the host system
110.
[0018] The controller 114 of the host system 110 may include a host
bus adaptor (HBA), that may be a stand-alone device or included as
a component in the host system 110. Examples of storage devices 120
include, but are not limited SAS hard disk drives, SATA hard disk
drives, etc. The host system 110 may include one or more of Serial
SCSI Protocol (SSP) ports typically used to communicate with SAS
drives, Serial ATA Tunneling Protocol (STP) ports typically used to
communicate with SATA drives, and/or Serial Management Protocol
(SMP) ports typically used to communicate with expanders in an SAS
domain.
[0019] It will be appreciated that the particular arrangement,
number, and configuration of components described herein is
exemplary and non-limiting. For example, SAS topology 100 may
implement any number of host systems, storage devices, and
associated communication paths. Furthermore, SAS topology 100 may
implement one or more expanders expand the number of ports used to
interconnect one or more host system(s) 110 with one or more
storage device(s) 120. The storage device(s) 120 may be either
standard SCSI protocol SAS devices or may be SATA protocol devices
coupled through the SAS domain.
[0020] FIG. 2a-b illustrates views of a connector receptacle 200
and plug 250 operable with a SAS topology. The receptacle 200 and
plug 250 comprise Mini-SAS connectors of the SFF-8644
specification. The SAS ports 112 and 122 of the host system 110 and
storage device 120, respectively, may therefore implement the
receptacle 200 shown in FIG. 2a. Similarly, each terminal end of
the SAS cable 130 may implement the plug 250 shown in FIG. 2b. The
receptacle 200 and plug 250 include four groups of pins A-D. FIG. 3
is a power-wire connecting diagram operable with the Mini-SAS
connectors 200 and 250 in an exemplary embodiment. As shown, each
group of pins A-D collectively provide ground pins and signal pins
(e.g., RX0+, RX0-, TX0-, and TX0+, etc.). More particularly, pins
B1 and D1 provide power Vact 134, and pins C1 and C1 are the
communication pins configured to determine whether the host system
110 is configured to supply enough power for the storage device
120.
[0021] FIG. 4 is a flowchart illustrating a method for powering a
storage device over a SAS interface in an exemplary embodiment. In
step 202, the SAS port 122 of the storage device 120 receives a
plug (e.g., cable 130) that communicates SAS compliant signals from
the host system 110. In step 204, the microcontroller 124 of the
storage device 120 detects a first power level on a power contact
of the SAS port 122. In other words, the microcontroller 124, being
integrated with the SAS port 122, detects power available on Vact
134 (i.e., pin B1 and D1) supplied from the host system 110. In one
embodiment, the first level of power is 1.5 watts since that is a
power level that is used for powering optical transceivers in the
SFF-8644 standard. In another embodiment, the microcontroller 124
comprises a low power microcontroller so that minimal energy is
expended by the host system 110 to enable the storage device 120 to
detect available power levels.
[0022] In step 206, the microcontroller 124 powers up a circuit
board of the storage device 120 to the first power level when it is
available from the host system 110. Thus, in one embodiment, the
microcontroller 124 uses up to 1.5 watts from Vact 134 if it is
available from the host system 110. In step 208, the
microcontroller 124 receives an I2C communication that indicates a
second power level is available from the host system 110. When the
second power level is available, the microcontroller 124 powers up
the circuit board of the storage device 120 to sufficiently power a
storage appliance. The I2C communication may be received from the
host 110 via pins C1 and C2 to indicate to the microcontroller 124
of the storage device 120 to power the storage device 120 via pins
B1 and D1.
[0023] Embodiments disclosed herein can take the form of software,
hardware, firmware, or various combinations thereof. In one
particular embodiment, software is used to direct controller 114
and/or microcontroller 124 to perform the various operations
disclosed herein. FIG. 5 illustrates an exemplary processing system
500 operable to execute a computer readable medium embodying
programmed instructions. Processing system 500 is operable to
perform the above operations by executing programmed instructions
tangibly embodied on computer readable storage medium 512. In this
regard, embodiments of the invention can take the form of a
computer program accessible via computer readable medium 512
providing program code for use by a computer (e.g., processing
system 500) or any other instruction execution system. For the
purposes of this description, computer readable storage medium 512
can be anything that can contain or store the program for use by
the computer (e.g., processing system 500).
[0024] Computer readable storage medium 512 can be an electronic,
magnetic, optical, electromagnetic, infrared, or semiconductor
device. Examples of computer readable storage medium 512 include a
solid state memory, a magnetic tape, a removable computer diskette,
a random access memory (RAM), a read-only memory (ROM), a rigid
magnetic disk, and an optical disk. Current examples of optical
disks include compact disk-read only memory (CD-ROM), compact
disk-read/write (CD-R/W), and DVD.
[0025] Processing system 500, being suitable for storing and/or
executing the program code, includes at least one processor 502
coupled to program and data memory 504 through a system bus 550.
Program and data memory 504 can include local memory employed
during actual execution of the program code, bulk storage, and
cache memories that provide temporary storage of at least some
program code and/or data in order to reduce the number of times the
code and/or data are retrieved from bulk storage during
execution.
[0026] Input/output or I/O devices 506 (including but not limited
to keyboards, displays, pointing devices, etc.) can be coupled
either directly or through intervening I/O controllers. Network
adapter interfaces 508 can also be integrated with the system to
enable processing system 500 to become coupled to other data
processing systems or storage devices through intervening private
or public networks. Modems, cable modems, IBM Channel attachments,
SCSI, Fibre Channel, and Ethernet cards are just a few of the
currently available types of network or host interface adapters.
Display device interface 510 can be integrated with the system to
interface to one or more display devices, such as printing systems
and screens for presentation of data generated by processor
502.
* * * * *