| .. SPDX-License-Identifier: GPL-2.0 |
| |
| ================= |
| PCI vNTB Function |
| ================= |
| |
| :Author: Frank Li <Frank.Li@nxp.com> |
| |
| The difference between PCI NTB function and PCI vNTB function is |
| |
| PCI NTB function need at two endpoint instances and connect HOST1 |
| and HOST2. |
| |
| PCI vNTB function only use one host and one endpoint(EP), use NTB |
| connect EP and PCI host |
| |
| .. code-block:: text |
| |
| |
| +------------+ +---------------------------------------+ |
| | | | | |
| +------------+ | +--------------+ |
| | NTB | | | NTB | |
| | NetDev | | | NetDev | |
| +------------+ | +--------------+ |
| | NTB | | | NTB | |
| | Transfer | | | Transfer | |
| +------------+ | +--------------+ |
| | | | | | |
| | PCI NTB | | | | |
| | EPF | | | | |
| | Driver | | | PCI Virtual | |
| | | +---------------+ | NTB Driver | |
| | | | PCI EP NTB |<------>| | |
| | | | FN Driver | | | |
| +------------+ +---------------+ +--------------+ |
| | | | | | | |
| | PCI BUS | <-----> | PCI EP BUS | | Virtual PCI | |
| | | PCI | | | BUS | |
| +------------+ +---------------+--------+--------------+ |
| PCI RC PCI EP |
| |
| Constructs used for Implementing vNTB |
| ===================================== |
| |
| 1) Config Region |
| 2) Self Scratchpad Registers |
| 3) Peer Scratchpad Registers |
| 4) Doorbell (DB) Registers |
| 5) Memory Window (MW) |
| |
| |
| Config Region: |
| -------------- |
| |
| It is same as PCI NTB Function driver |
| |
| Scratchpad Registers: |
| --------------------- |
| |
| It is appended after Config region. |
| |
| .. code-block:: text |
| |
| |
| +--------------------------------------------------+ Base |
| | | |
| | | |
| | | |
| | Common Config Register | |
| | | |
| | | |
| | | |
| +-----------------------+--------------------------+ Base + span_offset |
| | | | |
| | Peer Span Space | Span Space | |
| | | | |
| | | | |
| +-----------------------+--------------------------+ Base + span_offset |
| | | | + span_count * 4 |
| | | | |
| | Span Space | Peer Span Space | |
| | | | |
| +-----------------------+--------------------------+ |
| Virtual PCI Pcie Endpoint |
| NTB Driver NTB Driver |
| |
| |
| Doorbell Registers: |
| ------------------- |
| |
| Doorbell Registers are used by the hosts to interrupt each other. |
| |
| Memory Window: |
| -------------- |
| |
| Actual transfer of data between the two hosts will happen using the |
| memory window. |
| |
| Modeling Constructs: |
| ==================== |
| |
| 32-bit BARs. |
| |
| ====== =============== |
| BAR NO CONSTRUCTS USED |
| ====== =============== |
| BAR0 Config Region |
| BAR1 Doorbell |
| BAR2 Memory Window 1 |
| BAR3 Memory Window 2 |
| BAR4 Memory Window 3 |
| BAR5 Memory Window 4 |
| ====== =============== |
| |
| 64-bit BARs. |
| |
| ====== =============================== |
| BAR NO CONSTRUCTS USED |
| ====== =============================== |
| BAR0 Config Region + Scratchpad |
| BAR1 |
| BAR2 Doorbell |
| BAR3 |
| BAR4 Memory Window 1 |
| BAR5 |
| ====== =============================== |
| |
| |
