Device, system and method for communication with heterogeneous physical layers
A device to process data packets for communication across PHY layers which are of different respective communication protocols. In an embodiment, the device includes a first protocol stack and a second protocol stack which are each for a PCIe™ communication protocol. The first protocol stack and a second protocol stack may interface, respectively, with a first physical (PHY) layer and a second PHY layer of the device. The first protocol stack and the second protocol stack may exchange packets to facilitate communications via both the first PHY layer and the second PHY layer. In another embodiment, the first PHY layer is for communication according to the PCIe™ communication protocol and the second PHY layer is for communication according to another, comparatively low power communication protocol.
1. An apparatus, comprising:
a semiconductor chip comprising:
a PCIe physical layer interface;
a MIPI physical layer interface;
first PCIe protocol stack logic circuitry comprising first PCIe data link layer logic circuitry and first PCIe transactional layer logic circuitry, the first PCIe protocol stack logic circuitry coupled to the PCIe physical layer interface to process PCIe packets sent to/from the PCIe physical layer interface;
second PCIe protocol stack logic circuitry comprising second PCIe data link layer logic circuitry and second PCIe transactional layer logic circuitry, the second PCIe protocol stack logic circuitry coupled to the MIPI physical layer interface to process MIPI packets sent to/from the MIPI physical layer interface;
packet exchange logic circuitry coupled between the first PCIe protocol stack logic circuitry and the second PCIe protocol stack logic circuitry to enable transportation of packets between the PCIe physical layer interface and the MIPI physical layer interface in hardware.
2. The apparatus of claim 1 wherein the first PCIe protocol stack logic circuitry includes a link training and management layer logic circuitry.
3. The apparatus of claim 2 , wherein the link training and management layer logic circuitry comprises link training status and state machine (LTSSM) logic circuitry, wherein, in response to encountering an error in the LTSSM, transmitter circuitry and receiver circuitry of the PCIe interface is to transition to a first known state of the LTSSM and transition to a second known state after the transition to the first known state.
4. The apparatus of claim 3 , wherein the first known state is a STALL state.
5. The apparatus of claim 4 , wherein the second known state is HIBERN8.
6. A computing system, comprising:
a processor;
a memory control hub;
memory coupled to the memory control hub;
a PCIe physical layer interface;
a MIPI physical layer interface;
first PCIe protocol stack logic circuitry comprising first PCIe data link layer logic circuitry and first PCIe transactional layer logic circuitry, the first PCIe protocol stack logic circuitry coupled to the PCIe physical layer interface to process PCIe packets sent to/from the PCIe physical layer interface;
second PCIe protocol stack logic circuitry comprising second PCIe data link layer logic circuitry and second PCIe transactional layer logic circuitry, the second PCIe protocol stack logic circuitry coupled to the MIPI physical layer interface to process MIPI packets sent to/from the MIPI physical layer interface;
packet exchange logic circuitry coupled between the first PCIe protocol stack logic circuitry and the second PCIe protocol stack logic circuitry to enable transportation of packets between the PCIe physical layer interface and the MIPI physical layer interface in hardware.
7. The computing system of claim 6 wherein the first PCIe protocol stack logic circuitry includes a link training and management layer logic circuitry.
8. The computing system of claim 7 , wherein the link training and management layer logic circuitry comprises link training status and state machine (LTSSM) logic circuitry, wherein, in response to encountering an error in the LTSSM, transmitter circuitry and receiver circuitry of the PCIe interface is to transition to a first known state of the LTSSM and transition to a second known state after the transition to the first known state.
9. The computing system of claim 8 , wherein the first known state is a STALL state.
10. The computing system of claim 9 , wherein the second known state is HIBERN8.