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+# Frequently Asked Questions
+
+## General
+
+### What is ReviveSparc?
+
+ReviveSparc is a clean-room reimplementation of the OpenSPARC ISA (instruction set architecture). It aims to provide a fully open-source, legally unencumbered implementation of the SPARC V9 architecture that can run operating systems and software.
+
+### Is this affiliated with Oracle?
+
+No. ReviveSparc is an independent open-source project. OpenSPARC and SPARC are trademarks of Oracle Corporation. We are not affiliated with or endorsed by Oracle.
+
+### Why SPARC? Isn't it dead?
+
+SPARC is still used in mission-critical systems, particularly in aerospace, defense, and high-reliability computing. The Fujitsu SPARC64 processors power Japan's Fugaku supercomputer. The architecture is elegant and well-documented, making it ideal for educational use. ReviveSparc aims to preserve the architecture for future generations.
+
+## Technical
+
+### What is the "clean room" process?
+
+Developers implementing ReviveSparc have **no access** to the original OpenSPARC source code. We work exclusively from publicly available specification documents:
+- SPARC Architecture Manual Version 9
+- UltraSPARC T1/T2 Supplements
+- VIS Instruction Set Manual
+
+This ensures the code is entirely original and free from any AT&T licensing concerns that affected the original OpenSPARC codebase.
+
+### What operating systems can run?
+
+- **Linux** (6.x series, full support)
+- **NetBSD** (10.x, full support)
+- **OpenBSD** (7.x, in progress)
+- **Bare-metal programs** (any ELF binary for SPARC V9)
+
+### How fast is the emulator?
+
+On a modern x86_64 system:
+- Single-core, JIT disabled: ~50 MIPS
+- Single-core, JIT enabled: ~200 MIPS
+- 8-core, JIT enabled: ~800 MIPS aggregate
+
+Performance is sufficient to boot Linux in a few seconds.
+
+### Can I synthesize the RTL on an FPGA?
+
+Yes. The Verilog RTL has been tested on:
+- Xilinx Virtex-7 (XC7VX485T) — 4 cores at 50 MHz
+- Xilinx Kintex-7 (XC7K325T) — 2 cores at 75 MHz
+- Intel Arria 10 — 4 cores at 100 MHz
+
+See the [RTL Synthesis Guide](rtl-synthesis.md) for details.
+
+## Project
+
+### How can I contribute?
+
+See the [Community page](../community.html) for details. We welcome code contributions, documentation, testing, and hardware verification.
+
+### What license is used?
+
+BSD 2-Clause License. This permits both open-source and proprietary use, with minimal restrictions.
+
+### Does ReviveSparc include any AT&T code?
+
+No. ReviveSparc is a complete from-scratch reimplementation. Every line of code is original and written solely from the architecture specification.
+
+### Are there plans for SPARC V8 (32-bit) support?
+
+The emulator includes a SPARC V8 compatibility mode that handles 32-bit code. Pure 32-bit SPARC V8 is not a primary target, but the majority of V8 instructions are supported through the V9 backward compatibility features.
+
+### Can I run Solaris?
+
+Solaris 10 and Solaris 11 for SPARC are not currently supported. The primary targets are open-source operating systems. If you'd like to contribute Solaris support, please reach out on the mailing list.
+
+### Why not just use QEMU's SPARC target?
+
+QEMU's SPARC target is excellent for running SPARC binaries, but it is a functional emulator with less emphasis on:
+- Cycle-accurate pipeline modeling
+- Hardware synthesis targets
+- Educational clarity
+
+ReviveSparc complements QEMU by providing a reference implementation suitable for hardware design and teaching.
+
+## Build Issues
+
+### `make` fails with "undefined reference"
+
+Ensure you have all dependencies installed. See the [Build Guide](build-guide.md) for your platform.
+
+### The emulator crashes on startup
+
+Run with debug output enabled:
+
+```bash
+./sparc-emu -d -v kernel.bin
+```
+
+This will show detailed trace information. File a bug report with the output.
+
+### Linux kernel hangs during boot
+
+Common causes:
+- Missing or incorrect device tree blob (use the DTB from `revivesparc.dtb`)
+- Incorrect kernel command-line parameters
+- Kernel built without ReviveSparc platform support
+
+Try booting with `-append "earlyprintk debug"` to see kernel messages.