CN106708747A - Memory switching method and device - Google Patents

Abstract

The invention provides a memory switching method, the method comprising: configuring the high-speed cache memory Cache RAM as a tightly coupled memory TCM RAM; judging the memory to be accessed by the received request, when the memory to be accessed by the received request is Cache When using RAM, generate a request to access Cache RAM; when the type of memory to be accessed by the received request is TCM RAM, generate a request to access TCM RAM; send the generated access request to the corresponding RAM. The invention also provides a memory switching device.

Description

A memory switching method and device

technical field

The invention relates to data storage technology, in particular to a memory switching method and device for realizing dynamic switching between a cache memory (Cache) and a tightly coupled memory (TCM, Tightly Coupled Memory).

Background technique

In the processor architecture, the storage system is hierarchical. The closer the memory is to the core, the smaller the scale and the faster the read and write speed. In the existing processor system, in addition to L1 Cache and L2 Cache, most processor systems also have L1 TCM; L1 TCM is fast and the access time is deterministic, but it is usually small in scale and cannot fully meet the actual requirements. need. When a program that requires high access speed works or the data cannot fit in the L1 TCM, the usual practice is to define the program or the corresponding data as a cacheable attribute and store it in the Cache. However, the disadvantage of this is that after the cache has passed the query delay, the access time is relatively short if there is a hit, and the access time is still very long if there is no hit.

Contents of the invention

In view of this, the embodiments of the present invention expect to provide a memory switching method and device, which can effectively shorten memory access time and improve access performance.

In order to achieve the above object, technical solution of the present invention is achieved in that way:

An embodiment of the present invention provides a memory switching method, including:

Configure Cache RAM as TCM RAM;

Determine the memory to be accessed by the received request, when the memory to be accessed by the received request is Cache RAM, generate a request to access Cache RAM; when the type of memory to be accessed by the received request is TCM RAM, generate a request to access TCM RAM ask;

Send the generated access request to the corresponding RAM.

In the above solution, the configuration of Cache RAM as TCM RAM includes:

Configure part of Cache RAM as TCM RAM; or,

Configure all Cache RAM as TCM RAM.

In the above solution, the configuration of Cache RAM as TCM RAM includes:

Change the allocation algorithm of Cache RAM, and do not query and allocate the Cache RAM that will be configured as TCM RAM;

A one-to-one mapping between the TCM address space and the TCM RAM is established for the Cache RAM that does not perform query and allocation, and the Cache RAM is configured as a TCM RAM.

In the above solution, the method further includes: transferring the data in the Cache RAM to be configured as TCM RAM to memory.

In the above solution, the method further includes: restoring the TCM RAM to a Cache RAM, and transferring data in the TCM RAM to a memory.

The embodiment of the present invention also provides a memory switching device, which includes: a configuration module and a control module, wherein,

The configuration module is configured to configure the Cache RAM as TCM RAM;

The control module is used to determine the memory to be accessed by the received request, and when the memory to be accessed by the received request is Cache RAM, generate a request for accessing Cache RAM; when the memory type to be accessed by the received request is TCM RAM, generating a request to access the TCM RAM; sending the generated access request to the corresponding RAM.

In the above solution, the configuration module is specifically configured to: configure part of the Cache RAM as TCM RAM; or configure all the Cache RAM as TCM RAM.

In the above solution, the configuration module is specifically used for:

Change the allocation algorithm of Cache RAM, and do not query and allocate the Cache RAM that will be configured as TCM RAM;

A one-to-one mapping between the TCM address space and the TCM RAM is established for the Cache RAM that does not perform query and allocation, and the Cache RAM is configured as a TCM RAM.

In the above solution, the configuration module is further configured to: transfer the data in the CacheRAM to be configured as TCM RAM to memory.

In the above solution, the configuration module is further configured to: restore the TCM RAM to Cache RAM, and transfer the data in the TCM RAM to the memory.

The memory switching method and device provided by the embodiments of the present invention configure the Cache RAM as TCMRAM; judge the memory to be accessed by the received request, and generate a request to access the Cache RAM when the memory to be accessed by the received request is Cache RAM ; When the memory type to be accessed by the received request is TCM RAM, generate a request for accessing TCM RAM, and then send the generated access request to the corresponding RAM. In this way, the existing Cache RAM can be dynamically used as TCM, and the dynamic switching between TCM and Cache can be realized without increasing the cost of RAM; the access to Cache RAM and TCM RAM can be realized at the same time, and the data access speed is significantly improved , and ensure data consistency.

Description of drawings

FIG. 1 is a schematic flow chart of a memory switching method according to Embodiment 1 of the present invention;

FIG. 2 is a schematic flowchart of a memory switching method according to Embodiment 2 of the present invention;

3 is a schematic structural diagram of a memory switching device according to an embodiment of the present invention;

Fig. 4 is a schematic structural diagram of a control module according to an embodiment of the present invention.

detailed description

In the embodiment of the present invention, first Cache RAM is configured as TCM RAM; Then judge the memory that the request that receives needs to visit, when the memory that the request that receives needs to visit is Cache RAM, generate the request of accessing Cache RAM; When receiving The type of memory to be accessed by the request is TCMRAM, a request for accessing the TCM RAM is generated, and then the generated access request is sent to the corresponding RAM.

The implementation of the technical solutions of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. FIG. 1 is a schematic flow chart of a memory switching method according to Embodiment 1 of the present invention. As shown in FIG. 1 , the memory switching method of this embodiment includes the following steps:

Step 101: Cache RAM is configured as TCM RAM;

The described configuration of Cache RAM as TCM RAM includes: configuring part of Cache RAM as TCM RAM; or, configuring all of Cache RAM as TCM RAM; in practical applications, you can choose to configure part or all of Cache RAM as TCM RAM, for example, when the system requires high data read and write speed and involves a large amount of data, all CacheRAM can be configured as TCM RAM; when the system requires general data read and write speed, and the data involved When the amount is small, a part of Cache RAM can be configured as TCM RAM, and the address range of Cache RAM to be configured as TCM RAM can be determined according to actual needs.

Specifically, change the allocation algorithm of Cache RAM by changing the lockdown by way configuration of Cache RAM, and do not query and allocate the Cache RAM that will be configured as TCM RAM; establish the TCM address for the Cache RAM that will not be queried and allocated One-to-one mapping between space and TCM RAM, configuring the Cache RAM as TCM RAM.

In the embodiment of the present invention, before configuring the Cache RAM as a TCM RAM, the method further includes: transferring data in the Cache RAM to be configured as a TCM RAM to a memory.

Step 102: judging the memory to be accessed by the received request, when the memory to be accessed by the received request is Cache RAM, perform step 103; when the type of memory to be accessed by the received request is TCM RAM, perform step 104;

Step 103: generate a request for accessing the Cache RAM;

Step 104: Generate a request for accessing the TCM RAM;

In the embodiment of the present invention, since the TCM address space and the TCM RAM are mapped one by one, that is, accessing the TCM RAM is equivalent to a 100% hit, therefore, a request for accessing the TCM RAM can be directly generated; while accessing the Cache RAM, it is necessary to first inquire whether it is a hit , if hit, a request to access Cache RAM is generated to access the corresponding RAM; if there is no hit, it is necessary to access the next-level storage structure.

Step 105: Send the generated access request to the corresponding RAM.

In the embodiment of the present invention, after the request for accessing the Cache RAM and the request for accessing the TCM RAM are generated, arbitration processing is performed respectively, and the arbitrated request is obtained and sent to the corresponding RAM. In the embodiment of the present invention, the TCM RAM and the Cache RAM can be accessed at the same time, and the access control processes for the TCM RAM and the Cache RAM are independent of each other, thereby improving parallelism. In the case of accessing TCM RAM and Cache RAM at the same time, TCM RAM and Cache RAM may return data at the same time. Therefore, the data needs to be processed at the same time, the data read operation and/or write operation are completed, and the data and response are returned.

In the embodiment of the present invention, the method further includes: restoring the TCM RAM to a Cache RAM, and transferring data in the TCM RAM to a memory.

In the embodiment of the present invention, according to actual needs, when the system needs the TCM RAM, the Cache RAM is configured as the TCM RAM; when the system no longer needs the TCM RAM, the TCM RAM can be recovered as the Cache RAM; When the RAM is configured as a TCM RAM, the data in the Cache RAM can be transferred (flush) to the memory; when the TCM RAM is restored to the Cache RAM, the data in the TCM RAM can be transferred to the memory, thereby maintaining data consistency .

FIG. 2 is a schematic flow chart of a memory switching method in Embodiment 2 of the present invention. As shown in FIG. 2 , the memory switching method in this embodiment includes the following steps:

Step 201: close Cache RAM;

Step 202: transfer (flush) the data of the TCM RAM to be configured as the TCM RAM to the memory;

Step 203: configure the Cache RAM as TCM RAM;

In this step, you can choose to configure all or part of the Cache RAM as TCM RAM according to actual needs;

Step 204: open Cache RAM;

In this step, if it is the first time to open the Cache, you also need to complete the initialization of the Cache;

Step 205: Initialize TCM RAM;

In this step, the TCM can be filled by transferring data from the memory through DMA; other initialization methods can also be used, and are not limited to this range.

Step 206: Receive a request for accessing the TCM RAM and Cache RAM, and access the corresponding TCM RAM and Cache RAM according to the request;

Specifically, an access request for accessing the TCM RAM and the Cache RAM is generated according to the received request, and the corresponding TCM RAM and Cache RAM are accessed.

Step 207: When the TCM is not needed, transfer the data in the TCM to the memory;

In this step, if the data in the TCM needs to be saved, the data in the TCM can be moved to the memory through DMA.

Step 208: Restore the TCM RAM to Cache RAM.

Step 209: Access the Cache RAM.

If you want to reconfigure the Cache RAM as TCM RAM, then jump to step 201.

In the embodiment of the present invention, the existing Cache RAM is used as the TCM RAM dynamically, without adding new RAM, and without increasing the cost of the RAM, the dynamic switching between the TCM RAM and the Cache RAM can be realized, and the Cache RAM can be accessed at the same time part and TCM RAM part, can significantly improve data access speed. Since the address of the TCM RAM part is part of the entire address space, the memory switching method in the embodiment of the present invention can also ensure data consistency.

The embodiment of the present invention also provides a schematic structural diagram of a memory switching device, the device Cache controller, FIG. 3 is a schematic structural diagram of a memory switching device according to an embodiment of the present invention, as shown in FIG. 3 , the device includes: control module 32, wherein,

The configuration module 31 is configured to configure the Cache RAM as TCM RAM;

In the embodiment of the present invention, the configuration module is specifically configured to: configure part of the Cache RAM as TCM RAM; or configure all the Cache RAM as TCM RAM. In practical applications, you can choose to configure part or all of the Cache RAM as TCM RAM according to actual needs. For example, when the system requires high data read and write speed and the amount of data involved is large, all Configure as TCM RAM; when the system requires general data read and write speed and the amount of data involved is small, you can configure a part of Cache RAM as TCM RAM, and determine the address range of Cache RAM to be configured as TCM RAM according to actual needs.

Specifically, the configuration module 31 changes the allocation algorithm of the Cache RAM through the configuration of the lockdown by way of the changed Cache RAM, and does not inquire and allocate the Cache RAM to be configured as TCM RAM; The Cache RAM establishes a one-to-one mapping between the TCM address space and the TCM RAM, and configures the Cache RAM as a TCM RAM.

In the embodiment of the present invention, before the Cache RAM is configured as TCM RAM, the configuration module 31 is further configured to transfer the data in the Cache RAM to be configured as TCM RAM to the internal memory.

Described control module 32 is used for judging the memory that the request that receives will visit, when the memory that the request that receives will visit is Cache RAM, generate the request of accessing Cache RAM; When the memory that the request that receives needs to visit is The TCM RAM generates a request for accessing the TCM RAM; and sends the generated access request to the corresponding RAM.

Fig. 4 is a structural diagram of the control module according to the embodiment of the present invention. As shown in Fig. 4, the control module 32 includes a request receiving submodule 321, a first request generating submodule 322, a second request generating submodule 323, a first The arbitration submodule 324, the second arbitration submodule 325, and the response submodule 326, wherein,

The request receiving submodule 321 is used to receive a request, and judge the memory to be accessed by the received request, and when the memory to be accessed by the received request is Cache RAM, notify the first request generation submodule 322, when receiving When the memory type to be accessed by the request is TCM RAM, notify the second request generating submodule 323;

The first request generating submodule 322 is configured to generate a request for accessing the Cache RAM when the memory to be accessed by the received request is a Cache RAM; and send the request for accessing the Cache RAM to the first arbitration submodule 324 ;

The second request generating submodule 323 is configured to generate a request for accessing TCM RAM when the memory type to be accessed by the received request is TCM RAM; and send the request for accessing TCM RAM to the second arbitration submodule 325 ;

In the embodiment of the present invention, since the TCM address space and the TCM RAM are mapped one by one, that is, accessing the TCM RAM is equivalent to a 100% hit, therefore, a request for accessing the TCM RAM can be directly generated; while accessing the Cache RAM, it is necessary to first inquire whether it is a hit , if hit, a request to access Cache RAM is generated to access the corresponding RAM; if there is no hit, it is necessary to access the next-level storage structure.

The first arbitration submodule 324 is configured to arbitrate the received request for accessing the Cache RAM, and send the arbitrated request to the Cache RAM;

The second arbitration submodule 325 is configured to arbitrate the received request for accessing the TCM RAM, and send the arbitrated request to the TCM RAM;

The response sub-module 326 is used to process the data returned by the TCM RAM and the Cache RAM, complete the data read operation and/or write operation, and return data and a response;

In the embodiment of the present invention, after the request for accessing the Cache RAM and the request for accessing the TCM RAM are generated, arbitration processing is performed respectively, and the arbitrated request is obtained and sent to the corresponding RAM. In the embodiment of the present invention, the TCM RAM and the Cache RAM can be accessed at the same time, and the access control processes for the TCM RAM and the Cache RAM are independent of each other, thereby improving parallelism. In the case of accessing TCM RAM and Cache RAM at the same time, TCM RAM and Cache RAM may return data at the same time. Therefore, the data needs to be processed at the same time, the data read operation and/or write operation are completed, and the data and response are returned.

The configuration module 31 is further configured to: restore the TCM RAM to Cache RAM, and transfer the data in the TCM RAM to the memory.

In the embodiment of the present invention, the configuration module 31 configures Cache RAM as TCM RAM according to actual needs when the system needs TCM RAM; when the system no longer needs TCM RAM, the TCM RAM can be restored as Cache RAM; when the Cache RAM is configured as the TCM RAM, the data in the Cache RAM can be transferred (flush) to the internal memory; when the TCM RAM is recovered as the Cache RAM, the data in the TCM RAM can be transferred to the internal memory, thereby Maintain data consistency.

The implementation functions of each processing module in the memory switching device shown in FIGS. Those skilled in the art should understand that the functions of each processing module in the memory switching device shown in FIG. 3 can be realized by a program running on a processor, or by a specific logic circuit. CPU), microprocessor (MPU), digital signal processor (DSP), or field programmable gate array (FPGA) implementation.

In the several embodiments provided by the present invention, it should be understood that the disclosed methods and devices can be implemented in other ways. The device embodiments described above are only illustrative. For example, the division of the modules is only a logical function division. In actual implementation, there may be other division methods, such as: multiple modules or components can be combined, or May be integrated into another system, or some features may be ignored, or not implemented. In addition, the communication connection among the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or modules may be in electrical, mechanical or other forms.

The modules described above as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules, that is, they may be located in one place or distributed to multiple network modules; Part or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional module in each embodiment of the present invention can be integrated into one processing module, or each module can be used as a module separately, or two or more modules can be integrated into one module; the above-mentioned integration The modules can be implemented in the form of hardware, or in the form of hardware plus software function modules.

Those of ordinary skill in the art can understand that all or part of the steps to realize the above method embodiments can be completed by hardware related to program instructions, and the aforementioned programs can be stored in computer-readable storage media. When the program is executed, the execution includes The steps of the above-mentioned method embodiments; and the aforementioned storage medium includes: various media capable of storing program codes such as a removable storage device, a read-only memory (ROM, Read-Only Memory), a magnetic disk or an optical disk.

Alternatively, if the above-mentioned integrated modules in the embodiments of the present invention are implemented in the form of software function modules and sold or used as independent products, they may also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for Make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the methods described in various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program codes such as removable storage devices, ROMs, magnetic disks or optical disks.

The memory switching method and device described in the embodiments of the present invention only take the above embodiments as examples, but are not limited thereto. Those of ordinary skill in the art should understand that the technical solutions described in the foregoing embodiments can still be modified. Or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention.

Claims (10)

1. A memory switching method, the method comprising:

configuring a Cache RAM (random access memory) into a tightly coupled memory TCM RAM;

judging a memory to be accessed by the received request, and generating a request for accessing the Cache RAM when the memory to be accessed by the received request is the Cache RAM; when the type of a memory to be accessed by the received request is TCM RAM, generating a request for accessing the TCM RAM;

and sending the generated access request to the corresponding RAM.

2. The method of claim 1, wherein the configuring the Cache RAM as a TCMRAM comprises:

configuring part of Cache RAM into TCM RAM; or,

and configuring all Cache RAMs as TCM RAMs.

3. The method according to claim 1 or 2, wherein the configuring the Cache RAM as TCM RAM comprises:

changing the allocation algorithm of the Cache RAM, and not inquiring and allocating the Cache RAM to be configured into the TCM RAM;

and establishing one-to-one mapping between the TCM address space and the TCM RAM by using the Cache RAM which is not queried and distributed, and configuring the Cache RAM into the TCM RAM.

4. The method of claim 3, further comprising: and transferring the data in the Cache RAM to be configured into the TCM RAM to the memory.

5. The method of claim 1, further comprising: and recovering the TCMRAM into a Cache RAM, and transferring data in the TCM RAM to a memory.

6. A memory switching apparatus, the apparatus comprising: a configuration module and a control module, wherein,

the configuration module is used for configuring the Cache RAM into a tightly coupled memory TCM RAM;

the control module is used for judging a memory to be accessed by the received request, and generating a request for accessing the Cache RAM when the memory to be accessed by the received request is the Cache RAM; when the type of a memory to be accessed by the received request is TCM RAM, generating a request for accessing the TCM RAM; and sending the generated access request to the corresponding RAM.

7. The apparatus of claim 6, wherein the configuration module is specifically configured to: configuring part of Cache RAM into TCM RAM; alternatively, all Cache RAM is configured as TCM RAM.

8. The apparatus according to claim 6 or 7, wherein the configuration module is specifically configured to:

changing the allocation algorithm of the Cache RAM, and not inquiring and allocating the Cache RAM to be configured into the TCM RAM;

and establishing one-to-one mapping between the TCM address space and the TCM RAM by using the Cache RAM which is not queried and distributed, and configuring the Cache RAM into the TCM RAM.

9. The apparatus of claim 1, wherein the configuration module is further configured to: and transferring the data in the Cache RAM to be configured into the TCM RAM to the memory.

10. The apparatus of claim 6, wherein the configuration module is further configured to: and restoring the TCM RAM into a Cache RAM, and transferring data in the TCM RAM to a memory.