# Glossary

## Terms & Abbreviations

### General
| Term | Definition |
|------|------------|
| **GSP** | GPU System Processor - NVIDIA's on-GPU RISC-V microcontroller |
| **vGPU** | Virtual GPU - Partitioned GPU for multi-tenant workloads |
| **VF** | Virtual Function - Single vGPU instance with dedicated resources |
| **PF** | Physical Function - Host GPU managing VFs (SR-IOV) |
| **IOV** | I/O Virtualization - SR-IOV implementation |
| **RPC** | Remote Procedure Call - GSP-host communication protocol |
| **BAR** | Base Address Register - PCIe memory-mapped I/O window |
| **WPR** | Write/Read Protect Region - Memory isolation mechanism |
| **SR-IOV** | Single Root I/O Virtualization - PCIe virtualization standard |

### Firmware Architecture
| Term | Definition |
|------|------------|
| **RV64IMAC** | RISC-V 64-bit ISA with Integer, Multiply, Atomic, Compressed extensions |
| **Dispatcher** | Central RPC routing function (primary/secondary) |
| **Jump Table** | Array of function pointers for sub-command dispatch |
| **Sub-Command** | Specific operation within an RPC type |
| **Descriptor** | Return structure with ID and echoed parameters |
| **Entry Point** | Firmware boot address (0x04009000) |
| **Frame Guard** | Stack canary at 0x041DC350 |

### Memory Management
| Term | Definition |
|------|------------|
| **VRAM** | Video RAM - GPU local memory |
| **Sysmem** | System Memory - Host DRAM |
| **Page Table** | GPU virtual-to-physical mapping tables |
| **Pinning** | Locking pages for DMA access |
| **Bounce Buffer** | Intermediate buffer for data transfer |
| **Aperture** | Mappable BAR window size |
| **Backing Store** | Memory backing emulated BAR regions |

### RPC Types
| RPC | Name | Purpose |
|-----|------|---------|
| 0x01 | **ALLOC** | Allocate GPU memory |
| 0x02 | **FREE** | Free GPU memory |
| 0x03 | **MAP** | Map memory to VF address space |
| 0x04 | **UNMAP** | Unmap memory from VF |
| 0x05 | **PIN** | Pin pages for DMA |
| 0x06 | **UNPIN** | Unpin pages |
| 0x07 | **SCHEDULE** | VF scheduling control |
| 0x08 | **YIELD** | Voluntary yield |
| 0x09 | **NOTIFY** | Event notification |
| 0x0A | **BAR_TRAP** | BAR access emulation |
| 0x0B | **MIGRATE** | Live VF migration |
| 0x0C | **DEBUG** | Debug interface |

### Migration
| Term | Definition |
|------|------------|
| **Pre-copy** | Iterative page transfer while VF runs |
| **Post-copy** | Start VF on destination, fetch pages on demand |
| **Quiesce** | Pause VF for consistent state snapshot |
| **Dirty Page** | Page modified since last transfer |
| **Cutover** | Switch execution from source to destination |
| **Token** | Opaque migration context handle |

### BAR Emulation
| Term | Definition |
|------|------------|
| **BAR1** | Primary 32-bit BAR for register access |
| **Bar1Rest** | BAR1 state restoration |
| **ForceBarAccess** | Hypervisor bypass of VF permissions |
| **Aperture** | Configurable BAR window size/offset |

### WPR (Write/Read Protect Region)
| Term | Definition |
|------|------------|
| **Write Protect** | Trap on write access to region |
| **Read Protect** | Trap on read access to region |
| **NV_WPR** | NVIDIA-specific WPR extensions |
| **Completion** | Successful trap handling |
| **Timeout** | Trap handling exceeded time limit |

### Hardware Registers
| Register | Purpose |
|----------|---------|
| **Doorbell** | Host→GSP notification (PCIe BAR0 + 0x1000) |
| **Message Ring** | Shared memory for RPC messages |
| **Cache Manager** | 0x429B428 - Flush/invalidate |
| **Allocator Arena** | 0x429B450 - Memory allocation |
| **Global Error Flag** | 0x04296048 - Global error state |
| **Stack Canary** | 0x041DC350 - Frame integrity |

### Tools & Scripts
| Tool | Purpose |
|------|---------|
| **analyzeHeadless** | Ghidra headless analyzer |
| **DecompileFunctions.java** | Ghidra script for batch decompilation |
| **trace_all_subsystems.py** | Binary analysis script |
| **RPC_HANDLER_MAP.md** | Complete RPC address map |
| **FINAL_REPORT.md** | Full analysis report |

### Debugging
| Term | Definition |
|------|------------|
| **ebreak** | RISC-V breakpoint instruction (fatal in FW) |
| **String Ref** | Cross-reference to string literal |
| **XRef** | Cross-reference (code/data) |
| **Pcode** | Ghidra's intermediate representation |
| **VBIOS** | Video BIOS - firmware for GPU initialization |

### Calling Convention (RISC-V)
| Register | ABI Name | Purpose |
|----------|----------|---------|
| x0 | zero | Hardwired zero |
| x1 | ra | Return address |
| x2 | sp | Stack pointer |
| x3 | gp | Global pointer |
| x4 | tp | Thread pointer |
| x5-7 | t0-t2 | Temporaries |
| x8 | s0/fp | Frame pointer |
| x9 | s1 | Callee-saved (RA save) |
| x10-11 | a0-a1 | Arguments/returns |
| x12 | s4 | Callee-saved (RA save) |
| x13-17 | a2-a6 | Arguments |
| x18-27 | s2-s11 | Callee-saved |
| x28-31 | t3-t6 | Temporaries |

### Firmware Sections (ELF)
| Section | Purpose |
|---------|---------|
| `.text` | Executable code |
| `.rodata` | Read-only data |
| `.data` | Initialized data |
| `.bss` | Zero-initialized data |
| `.section_task_rm_*` | Task-specific sections |

### Migration Phases
| Phase | Description |
|-------|-------------|
| **QUERY** | Check migratability |
| **PREPARE** | Quiesce, snapshot |
| **TRANSFER** | Iterative page copy |
| **COMMIT** | Final sync, cutover |
| **CLEANUP** | Release resources |

## File Naming Conventions

### Decompiled Output
```
FUN_ram_<ADDRESS>_ram_<ADDRESS>.c
```
- `FUN_ram_057A1AC0_ram_057A1AC0.c` = Function at 0x057A1AC0

### Ghidra Projects
```
gsp-<purpose>/
```
- `gsp-subcmds`, `gsp-rpc-handlers`, `gsp-bar-fns`, etc.

## References
- RISC-V ISA: https://riscv.org/technical/specifications/
- SR-IOV Spec: https://pcisig.com/specifications/iov/
- Ghidra: https://ghidra-sre.org/