Memory switching control apparatus using open serial interface, operating method thereof, and data storage device therefor

• US 20090083457A1
• Filed: 05/01/2008
• Published: 03/26/2009
• Est. Priority Date: 09/21/2007
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Nam, Kook Jin, Ahn, Byung Jun, Choi, Woo Young, Kim, Bup Joong
• Granted Patent: US 8,612,713 B2
• Time in Patent Office: Days
• US Class Current: 710/56
• CPC Class Codes: G06F 12/0646 Configuration or reconfiguration
• CPC Class Codes: G06F 13/1657 Access to multiple memories

Abstract

Provided is a memory switching control apparatus using an open serial interfacing scheme capable of enhancing flexibility, reliability, availability, performance in a data communication processes between a memory and a processing unit and an operating method thereof. The memory switching control apparatus includes: one or more processor interfacing units which perform interfacing with one or more processing units; one or more memory interfacing units which have open-serial-interfacing-scheme memory interfacing ports to interface with data storage devices connected to the memory interfacing ports in a serial interfacing scheme; and a plurality of arbitrating units which are provided corresponding to the memory interfacing units to independently arbitrate usage rights of the processor interfacing units to the memory interfacing units.

Claims

1. A memory switching control apparatus using an open serial interfacing, comprising:

one or more processor interfacing units which perform interfacing with one or more processing units;

one or more memory interfacing units which respectively have open-serial-interfacing-scheme memory interfacing ports to interface with data storage devices connected to the memory interfacing ports in a serial interfacing scheme; and

a plurality of arbitrating units which are provided corresponding to the memory interfacing units to independently arbitrate usage rights of the processor interfacing units to the memory interfacing units.

2. The memory switching control apparatus of claim 1, further comprising a memory port table which manages memory start addresses allocated to the respective memory interfacing units, memory sizes of the data storage devices connected to the memory interfacing ports or memory end addresses allocated thereto, and state information of the memory interfacing units.

3. The memory switching control apparatus of claim 1, wherein the number of interfacing lines of the memory interfacing units is varied according to required bandwidths of the connected data storage devices.

4. The memory switching control apparatus of claim 1, wherein the memory interfacing unit comprises:

a link unit which generates memory packets by combining data bus signals and control bus signals applied by the processor interfacing units, converts the memory packets to interfacing line packets by adjusting data widths of the memory packets, converts the interfacing line packets to memory packets, and extracts data bus signals and control bus signals from the memory packets; and

a physical-layer processor which performs a physical-layer process on the interfacing line packets inputted and outputted between the link unit and the interfacing lines.

5. The memory switching control apparatus of claim 2, wherein the memory start address, the memory size or the memory end addresses allocated to each memory interfacing unit is varied according to a memory capacity of the data storage device connected to the memory interfacing unit.

6. The memory switching control apparatus of claim 2, wherein the processor interfacing unit is one of:

a first processor interfacing unit which is directly connected to a processing unit through an internal bus to interface a memory access to the processing unit; and

a second processor interfacing unit which is connected to an external processing unit through an external interface to interface a memory access to the external processing unit.

7. The memory switching control apparatus of claim 2, wherein the processor interfacing unit comprises:

a data buffer which temporarily stores data, a memory address, a control signal, and a state signal inputted to and outputted from the processing unit and adjusts data width and speed of data inputted to and outputted from the memory interfacing unit; and

a decoder and a controller which identifies the memory interfacing unit which is to be requested to be accessed, based on the memory address, the control signal, and the state signal stored in the data buffer and the memory port table, requests for a usage right, and adjusts a data exchange timing for the memory interfacing unit.

8. The memory switching control apparatus of claim 2, wherein the arbitrating unit comprises:

a controller which allocates a usage right to a memory interfacing port to the processor interfacing units based on a usability of the memory interfacing unit and priorities of the processor interfacing units when a request for the usage right to the memory interfacing port is received from the processor interfacing units; and

a selection unit which selectively connects the processor interfacing units to the memory interfacing unit according to the usage right allocated by the controller.

9. The memory switching control apparatus of claim 4, wherein the link unit comprises:

a data input/output bus through which data bus signals including reading data and writing data are inputted to and outputted from the processor interfacing units;

a control input bus through which control bus signals including memory addresses, reading control signals, writing control signals, and state signals are inputted from the processor interfacing units;

a control output bus through which the control bus signals including the memory addresses, the reading control signals, the writing control signals, and the state signals are outputted to the processor interfacing units;

a data mixing/extracting unit which mixes the data bus signals inputted through the data input/output bus and the control bus signals inputted through the control input bus to output memory packets and extracts data bus signals and control bus signals from inputted memory packets to output the data bus signals and the control bus signals through the data input/output bus and the control output bus; and

an asymmetric buffer unit which adjusts widths of the memory packets outputted from the data mixing/extracting unit to converts the memory packets to interfacing line packets or adjusts data widths of the inputted interfacing line packets to converts the interfacing line packets to the memory packets to output the memory packets to the data mixing/extracting unit.

10. The memory switching control apparatus of claim 4, wherein the physical-layer processor is constructed with one or more of:

a scrambling/descrambling unit which performing scheduled data conversion and recovery so as to reduce electro magnetic interference (EMI) caused from occurrence of data having a repetitive equal pattern in the interfacing line packet;

an encoding/decoding unit which performs encoding and decoding so as to facilitate clock synchronization for the interfacing line packet, maintain a DC voltage balance of the interfacing line, and limit a frequency band of a data pattern; and

a data aligning unit which compensates for data delays between the interfacing lines.

11. The memory switching control apparatus of claim 4, wherein the memory packet comprises:

an information block including one or more of interfacing scheme version information, ID indicating an memory-accessing request entity and a sequence number, a memory address, a data size, control information, state information, and an error check code; and

a data block including reading data and writing data.

12. The memory switching control apparatus of claim 9, wherein the asymmetric buffer unit comprises:

an asymmetric bidirectional data buffer which has A and B sides in an asymmetric input/output structure to temporarily store memory packets inputted from the A side and output interfacing line packets through the B side and temporarily store interfacing line packets inputted from the B side and output memory packets through the A side;

an input/output control circuit which controls input and output flows of the memory packets and the interfacing line packets of the asymmetric bidirectional data buffer.

13. The memory switching control apparatus of claim 9, wherein the asymmetric buffer unit comprises:

a first asymmetric bidirectional data buffer which has A and B sides in an asymmetric input/output structure to receive memory packets through the A side and temporarily store the packets and output interfacing line packets through the B side;

a second asymmetric bidirectional data buffer which has A and B sides in an asymmetric input/output structure to receive interfacing line packets through the A side and temporarily store the interfacing line packets and output memory packets through the B side;

an input/output control circuit which controls input and output flows of the memory packets and the interfacing line packets of the first asymmetric bidirectional data buffer and the second asymmetric bidirectional data buffer.

14. The memory switching control apparatus of claim 9, wherein the asymmetric buffer unit comprises:

a plurality of asymmetric bidirectional data buffers, each of which has A and B sides in an asymmetric input/output structure to input and output memory packets through the A side and input and output interfacing line packets through the B side, wherein data widths inputted and outputted through the B side are set to be different;

an input/output control circuit which controls input and output flows of the memory packets and the interfacing line packets of the asymmetric bidirectional data buffers; and

a selection unit which selects an asymmetric bidirectional data buffer according to the widths of interfacing lines so as for the asymmetric bidirectional data buffer having the same data width to input and output the interfacing line packets.

15. The memory switching control apparatus of claim 9, wherein the asymmetric buffer unit comprises:

a plurality of first asymmetric bidirectional data buffers, each has A and B sides in an asymmetric input/output structure to receive memory packets through the A side and output interfacing line packets through the B side, wherein data output widths of the B side are set to be different;

a plurality of second asymmetric bidirectional data buffers, each has A and B sides in an asymmetric input/output structure to receive interfacing line packets through the A side and output memory packets through the B side, wherein data output widths of the A side are set to be different;

an input/output control circuit which controls input and output flows of the memory packets and the interfacing line packets of the first asymmetric bidirectional data buffer and the second asymmetric bidirectional data buffer; and

a selection unit which selects first and second asymmetric bidirectional data buffers according to the widths of interfacing lines so as for the first and second asymmetric bidirectional data buffers having the same data width to input and output the interfacing line packets.

16. The memory switching control apparatus of claim 12 wherein the input/output control circuit comprises a plurality of 3-state buffers which are provided to output lines of the memory packets and the interfacing line packets to operate in an open state or a normal state according to input and output of data.

17. The memory switching control apparatus of claim 14, wherein the selection unit checks the number of available interfacing lines among the interfacing lines connected to the data storage devices at an initial operation and performs the selection operation according to the number of available interfacing lines.

18. The memory switching control apparatus of 11, wherein the ID is generated by combining information of the processor interfacing unit which issues the memory-accessing request and specific request sequence information of the processor interfacing unit.

19. An operating method of a memory switching control apparatus using an open serial interfacing scheme, the memory switching control apparatus having a plurality of processor interfacing units connected to a plurality of processing units, a plurality of memory interfacing units connected to a plurality of data storage devices, and a plurality of arbitrating units arbitrating usage right to the memory interfacing units, the operating method comprising:

if an initialization operation is started, driving the memory interfacing units at corresponding lowest speeds so as to check the number of available interfacing lines;

checking a highest speed of the checked available interfacing lines; and

driving all the checked available interfacing lines at the checked highest speed so as to determine whether or not the available interfacing lines operate normally;

measuring data delays between the interfacing lines that are determined to operate normally and compensating for the data delays between the interfacing lines;

performing a memory test for data storage devices connected to the normally-operated interfacing lines; and

if the result of the memory test is normal, allocating system addressing spaces mapped to the data storage devices to each of the memory interfacing units and registrating thereof in a memory port table.

20. The operating method of claim 19, further comprising, if the result of the memory test is not normal, notifying an error state.

21. The operating method of claim 19, further comprising:

if a reading request issued from an arbitrary processing unit, a corresponding processor interfacing unit buffering a memory address of which reading is requested by the processing unit and a control signal;

the processor interfacing unit identifying a memory interfacing unit that is to read data from a currently-registered memory port table by using the buffered memory address information;

the processor interfacing unit requesting for a usage right to a memory interfacing port to an arbitrating unit of the identified memory interfacing unit;

the arbitrating unit allocating a usage right of a memory interfacing port to the processor interfacing unit according to a usability of the memory interfacing unit and a priority of the processor interfacing unit;

applying the memory address and the control signal buffered in the processor interfacing unit through the memory interfacing unit to the data storage device according to the allocation;

the memory interfacing unit receiving the reading-requested data from the data storage device;

the arbitrating unit identifying the processor interfacing unit which requests for data received by the memory interfacing unit;

transferring the data received by the memory interfacing unit to the identified processor interfacing unit; and

the processor interfacing unit receiving the data and transferring the data to the corresponding processing unit.

22. The operating method of claim 21, further comprising after the identifying of the processor interfacing unit that requests for the received data, the arbitrating unit notifying the identified processor interfacing unit that the reading-requested data are prepared.

23. The operating method of claim 19, further comprising:

if a writing request is issued from an arbitrary processing unit, a processor interfacing unit connected to the processing unit buffering a memory address of which writing is requested by the processing unit, a control signal, and data that are to be written in a memory;

the processor interfacing unit identifying a memory interfacing unit corresponding to the memory address by searching for the memory port table by using the buffered memory address;

the processor interfacing unit requesting for a usage right to a memory interfacing port to an arbitrating unit of the identified memory interfacing unit;

the arbitrating unit allocating a usage right of memory interfacing port to the processor interfacing unit according to a usability of the memory interfacing unit and a priority of the processor interfacing unit;

transferring the data, the memory address, and the control signal buffered in the processor interfacing unit which is allocated with the usage right to the memory interfacing unit; and

the memory interfacing unit transmitting the data, the memory address, and the control signal to the data storage device so as to request for writing.

24. The operating method of claim 23, further comprising:

the memory interfacing unit receiving an response to the writing request from the data storage device;

the arbitrating unit identifying a processor interfacing unit to which the response received by the memory interfacing unit is transferred;

the memory interfacing unit transferring the received response to the identified processor interfacing unit; and

the processor interfacing unit transmitting the transferred response to the corresponding processing unit.

25. A data storage device comprising:

one or more memory devices; and

one or more memory interfacing units, each of which an open-serial-interfacing-scheme memory interfacing port separately or commonly connected to the memory devices, wherein the memory interfacing unit receives a predetermined format of data through interfacing lines connected to the memory interfacing port to transfer the data to the memory devices or converts the data read from the memory devices to the predetermined format of data to output the data to the memory interfacing port.