System and method for facilitating data transfer using a shared non-deterministic bus
View Patent ↗System and method for facilitating data transfer between logic systems and a memory according to various conditions. Embodiments include systems and methods for facilitating and improving throughput of data transfers using a shared non-deterministic bus, a system and method for managing a memory as a circular buffer, and a system and method for facilitating data transfer between a first clock domain and a second clock domain. Embodiments may be implemented individually or in combination.
1. A system for facilitating data transfers with a shared non-local memory, comprising:
a radio frequency (RF) subsystem including an antenna for receiving data;
one or more signal processors to process the data; and
a first data transfer controller for facilitating transfer of the data between the system and the shared non-local memory over a non-deterministic bus shared by at least a second data transfer controller, the first data transfer controller to:
receive a real-time data transfer request from the RF subsystem to transfer real-time data to the shared non-local memory;
assign a first priority level to the real-time data transfer request;
receive a playback data transfer request from the one or more signal processors to transfer playback data between the one or more signal processors and the shared non-local memory;
assign a second priority level to the playback data transfer request; and
initiate a real-time data transfer corresponding to the real-time data transfer request based on the first priority level being higher than the second priority level.
2. The system of claim 1 ,
wherein the one or more signal processors include a PreSummer and a Fast Fourier Transform component.
3. The system of claim 2 ,
wherein the real-time data transfer request corresponds to a request to write Global Positioning System (GPS) data or global navigational satellite system (GLONASS) data to the shared non-local memory in order to be processed by the PreSummer and the Fast Fourier Transform component in real-time.
4. The system of claim 1 , wherein the first data transfer controller is further to:
wait, initially, in a fully idle state in which data transfer requests are not accepted;
transition to a ready idle state in which data transfer requests are accepted, wherein the real-time and playback data transfer requests are received when the first data transfer controller is in the ready idle state;
determine that a fatal error has occurred after initiating the real-time data transfer, the fatal error corresponding to either (i) a request for real-time data that has been overwritten in a local buffer of the RF subsystem and not yet transferred to the shared non-local memory, or (ii) a request that the first data transfer controller cease use of the non-deterministic bus; and
in response to determining that the fatal error has occurred, complete the real-time data transfer and transition to the fully idle state until the fatal error is lifted.
5. The system of claim 1 , wherein the first data transfer controller is further to:
wait, initially, in a fully idle state in which data transfer requests are not accepted;
transition to a ready idle state in which data transfer requests are accepted, wherein the real-time and playback data transfer requests are received when the first data controller is in the ready idle state;
determine that a critical error has occurred after initiating the real-time data transfer, the critical error corresponding to either (i) an invalid data transfer request, or (ii) a data transfer request for overwritten data in the shared non-local memory; and
in response to determining that the critical error has occurred, terminate the real-time data transfer and transition to the ready idle state until the critical error is lifted.
6. The system of claim 1 , wherein the system is a global navigational satellite (GNS) system, and wherein the real-time data transfer is for GNS data.
7. The system of claim 6 , wherein the one or more signal processors are to process both global positioning system (GPS) and global navigation satellite system (GLONASS) data.
8. The system of claim 1 ,
wherein the first data transfer controller comprises a finite state machine implemented in hardware.
9. The system of claim 1 ,
wherein the system and the shared non-local memory operate in different clock domains.
10. A method for facilitating data transfers between a system, including a first data transfer controller, and a shared non-local memory over a non-deterministic bus shared by at least a second data transfer controller, the method being performed by the first data transfer controller and comprising:
receiving a real-time data transfer request from a radio frequency (RF) subsystem, included in the system, to transfer real-time data to the shared non-local memory;
assigning a first priority level to the real-time data transfer request;
receiving a playback data transfer request from a signal processor, included in the system, to transfer playback data between the signal processor and the shared non-local memory;
assigning a second priority level to the playback data transfer request; and
initiating a real-time data transfer corresponding to the real-time data transfer request based on the first priority level being higher than the second priority level.
11. The method of claim 10 ,
wherein the signal processor includes a PreSummer and a Fast Fourier Transform component.
12. The method of claim 11 ,
wherein the real-time data transfer request corresponds to a request to write Global Positioning System (GPS) data or global navigational satellite system (GLONASS) data to the shared non-local memory in order to be processed by the PreSummer and the Fast Fourier Transform component in real-time.
13. The method of claim 10 , further comprising:
waiting, initially, in a fully idle state in which data transfer requests are not accepted;
transitioning to a ready idle state in which data transfer requests are accepted, wherein the real-time and playback data transfer requests are received when the first data transfer controller is in the ready idle state;
determining that a fatal error has occurred after initiating the real-time data transfer, the fatal error corresponding to either (i) a request for real-time data that has been overwritten in a local buffer of the RF subsystem and not yet transferred to the shared non-local memory, or (ii) a request that the first data transfer controller cease use of the non-deterministic bus; and
in response to determining that the fatal error has occurred, completing the real-time data transfer and transitioning to the fully idle state until the fatal error is lifted.
14. The method of claim 10 , further comprising:
waiting, initially, in a fully idle state in which transfer requests are not accepted;
transitioning to a ready idle state in which data transfer requests are accepted, wherein the real-time and playback data transfer requests are received when the first data transfer controller is in the ready idle state;
determining that a critical error has occurred after initiating the real-time data transfer, the critical error corresponding to either (i) an invalid data transfer request, or (ii) a data transfer request for overwritten data in the shared non-local memory; and
in response to determining that the critical error has occurred, terminating the real-time data transfer and transitioning to the ready idle state until the critical error is lifted.
15. The method of claim 10 ,
wherein the system is a global navigational satellite (GNS) system, and wherein the real-time data transfer is for GNS data.
16. The method of claim 15 , wherein the signal processor is to process both global positioning system (GPS) and global navigation satellite system (GLONASS) data.
17. The method of claim 10 ,
wherein the system and the shared non-local memory operate in different clock domains.
18. A global navigational satellite (GNS) system, comprising:
a radio frequency (RF) subsystem including an antenna for receiving data;
one or more digital signal processors to process the data; and
a first data transfer controller for facilitating transfer of the data between the GNS system and a shared non-local memory accessible via a non-deterministic bus shared by at least a second data transfer controller, the first data transfer controller to:
receive a real-time data transfer request from the RF subsystem to transfer real-time data to the shared non-local memory;
assign a first priority level to the real-time data transfer request;
receive a playback data transfer request from the one or more digital signal processors to transfer playback data between the one or more digital signal processors and the shared non-local memory;
assign a second priority level to the playback data transfer request; and
initiate a real-time data transfer corresponding to the real-time data transfer request based on the first priority level being higher than the second priority level.