Patent Application
20060075155
The description herein relates to information handling systems having serial attached small computer systems interface (“SAS”) controllers.
As the value and use of information continue to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system (“IHS”) generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
Serial attached small computer systems interface (“SAS”) and serial advanced technology attachment (“SATA”) storage devices (e.g., disk drives) are both capable of being coupled to a SAS interface (e.g., a “connector”). For example, a SAS controller with a SAS interface is capable of being coupled to either a SAS disk drive or a SATA disk drive via the same interface. Such compatibility may cause various problems such as a user undesirably or inadvertently connecting to a SAS controller, a SATA disk drive instead of a SAS disk drive, and vice versa.
What is needed is a method and an IHS without the disadvantages discussed above.
Accordingly, it is determined whether a storage device that is coupled to a serial attached small computer systems interface (“SAS”) interface is a SAS storage device or a serial attached advanced technology attachment (“SATA”) storage device.
For purposes of this disclosure, an information handling system (“IHS”) includes any instrumentality or aggregate of instrumentalities operable to compute, classify, process, transmit, receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, or other purposes. For example, an information handling system may be a personal computer, a server computer, a storage enclosure, a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The information handling system may include random access memory (RAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional components of the information handling system may include one or more disk drives, one or more network ports for communicating with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, and a video display. The information handling system may also include one or more buses operable to transmit communications between the various hardware components.
The chipset 110 further acts as a controller for main memory 115 which is coupled thereto. The chipset 110 also acts as an input/output (“I/O”) controller hub (ICH) which performs I/O functions. A USB controller 170 is coupled to chipset 110 so that devices such as a peripheral device 175 can be connected to the chipset 110 and the processor 105. Examples of the peripheral device 175 include printers, cameras, scanners, audio players, and other suitable devices. Although the peripheral device 175 communicates with the IHS 100 via a USB interface in the illustrative embodiment, in other embodiments, the peripheral device 175 communicates with the IHS 100 via another type of interface such as serial, parallel, FireWire, and/or any other suitable connection interface. A system basic input-output system (“BIOS”) 140 is coupled to chipset 110 as shown. The BIOS 140 is stored in CMOS or FLASH memory so that it is nonvolatile.
A local area network (LAN) controller 145, alternatively called a network interface controller (NIC), is coupled to the chipset 110 to facilitate connection of the IHS 100 to other IHSs. A media driver controller 150 is coupled to chipset 110 so that devices such as media drives 155 can be connected to the chipset 110 and the processor 105. Examples of the media devices 155 capable of being coupled to the media controller 150 include CD-ROM drives, DVD drives, hard disk drives and other fixed or removable media drives. An expansion bus 120, such as a peripheral component interconnect (PCI) bus, PCI express bus is coupled to the chipset 110 as shown. Via the expansion bus 120, a storage enclosure controller (e.g., a host bus adapter) 122 is also coupled to the chipset 110.
In the illustrative embodiment, the IHS 100 is a server. For providing the IHS 100 with storage capacity, a storage enclosure is coupled to the IHS 100 via the controller 122. Accordingly,
The storage enclosure 200 includes controller cards 202 and 204. Each of the controller cards 202 and 204 includes expanders. For example, the controller card 202 includes expanders 206, 208, 210, and the controller 204 includes expanders 212, 214, and 216. Via one or more of the expanders 206, 208, 210, 212, 214, or 216, one or more storage devices (e.g., SAS drives or SATA drives) are capable of being coupled to the controller card 202.
Within each of the controller cards 202 and 204, one or more of the expanders are capable of operating as an interface between the controller 122 and other expanders. For example, within the controller card 202, the expander 206 is an interface between the controller 122 and the other expanders 208 and 210.
The enclosure 200 also includes a back pane 218, which includes interfaces 220, 222, 224, and 226. Via the interfaces 220, 222, 224, and 226, one or more SAS drives and/or SATA drives are capable of being coupled to one or more of the expanders included by the controller cards 202 and 204. Accordingly, the enclosure 200 includes SAS/SATA storage devices 228, 230, 232, and 234, which are respectively coupled to the expanders 208, 220, 214, and 216 via the interfaces 220, 222, 224, and 226.
Although
The interface 300 includes a first port (e.g., port A) 302 and a second port (e.g., port B) 304. Each of the ports 302 and 304 includes one or more transmit (“TX”) wires (e.g., “pins”), receive (“RX”) wires, and ground (“GND”) wires. For example, the port 302 includes GND pins 306, 312, and 318. The port 302 also includes TX pins 308 and 310. Moreover, the port 302 includes RX pins 314 and 316.
Similar to the port 302, the port 304 includes GND pins 320, 326, and 332, TX pins 322 and 324, and RX pins 328 and 330. The GND pin 332 is coupled to a detection circuit, indicated generally at 334, that detects whether a SAS storage device or a SATA storage device is coupled to the interface 300. The detection circuit 334 includes a resistor (e.g., a “pull-up” resistor) 336. In the illustrative embodiment, the pull-up resistor 336 is an approximately 4.7 kilo-ohm pull-up resistor. The detection circuit 334 also includes a capacitor 338. In one example, the capacitor 338 is an approximately 1 uF capacitor. Each of the pull-up resistor 336 and the capacitor 338 is coupled to the GND pin 332.
The detection circuit 334 is coupled to a voltage source 340 via the pull up resistor 334. In the illustrative embodiment, voltage supplied by the voltage source 340 is approximately 5 volts. Also, the detection circuit 334 is coupled to a logic device 342 (e.g., a processor or a complex programmable logic device (“CPLD”), a field programmable gate array (“FPGA”) or a comparator circuit). The logic device 342 is also coupled to the GND pin 332. In at least one alternative embodiment, the detection circuit 336 includes the logic device 342.
Each of the ports 402 and 404 includes one or more GND, TX, and RX pins. For example, the port 402 includes GND pins 406, 412, and 418, TX pins 408 and 410, and RX pins 414 and 416. The port 404 includes GND pins 420, 426, and 432, TX pins 422 and 424, and RX pins 428 and 430.
As discussed above, the detection circuit 334 determines (e.g., detects) whether a SAS storage device or a SATA storage device is coupled to the interface 300. In one example, the detection circuit 334 makes such determination by determining whether an SAS storage device is coupled to the interface 300. For example, if the detection circuit 334 determines that a SAS storage device is not coupled to the interface 300, the detection circuit 334 determines that a SATA storage device is coupled to the interface 300.
In one embodiment, the detection circuit 334 determines whether a storage device that is coupled to the interface 300 is a SAS storage device or a SATA storage device by determining whether the storage device includes two ports (e.g., ports A and B). As shown in
In more detail, referring again to
Alternatively, in response to a SAS storage device, such as the SAS storage device 400, being coupled to the interface 300, the GND pin 332 is also coupled to the GND pin 432. In such situation, the signal on the GND pin 332 is pulled down to 0 volts indicating a second logic signal (e.g., logic 0). Such signal indicates (e.g., to the logic device 342) that a storage device that is coupled to the interface 300 is a SAS storage device. The logic device 342 receives such signal of the GND pin 332.
Referring again to
Although illustrative embodiments have been shown and described, a wide range of modification, change and substitution is contemplated in the foregoing disclosure. Also, in some instances, some features of the embodiments may be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be constructed broadly and in manner consistent with the scope of the embodiments disclosed herein.
