config.py.example

# Copyright (c) 2026 PeraMorphIQ
# SPDX-License-Identifier: BSD-3-Clause
#
# This file is part of Pera-OpenRAM.
# Developed by the PeraCom Neuromorphic Research Group.
#
# Author: PeraMorphIQ Team

# ==============================================================================
# PeraMorphIQ SRAM Configuration Example
# ==============================================================================
# Copy this file to config.py and edit the parameters below
# Then run: python generate_sram.py
# ==============================================================================

# ==============================================================================
# SRAM Architecture Parameters
# ==============================================================================

# Word size: Number of bits per word (data width)
# Common values: 8, 16, 32, 64, 128, 256
word_size = 64

# Number of words: Depth of the SRAM (number of addressable locations)
# Must be a power of 2: 32, 64, 128, 256, 512, 1024, 2048, 4096, etc.
num_words = 256

# Number of banks: TOTAL number of physical macro instances in the array.
# Must be a power of 2 (1, 2, 4, 8, etc.) and equal to num_h_banks * num_v_banks.
# More banks = better performance but larger area
num_banks = 1

# Banking mode: "vertical", "horizontal" or "mixed" (for multi-bank SRAMs)
#
# "vertical" (default): Address space divided across banks
#   - Each bank stores different words
#   - Bank selection via address bits
#   - Example: 4 banks, 2048 words → each bank has 512 words
#   - Use case: Standard multi-bank SRAM
#
# "horizontal": Word width divided across banks (bit-slicing)
#   - Each bank stores portion of bits for ALL words
#   - All banks accessed in parallel
#   - Example: 1024-bit word, 4 banks → each bank has 256 bits
#   - Advantage: No bank mux latency, better for wide words
#   - Use case: Cache lines, vector processors, wide data paths
#
# "mixed": BOTH axes at once (a num_v_banks x num_h_banks array)
#   - ONE macro of (word_size / num_h_banks) bits x (num_words / num_v_banks)
#     words is generated; <name>_top.v instantiates num_h_banks * num_v_banks
#     copies of it.
#   - Top log2(num_v_banks) address bits select the vertical group; all
#     num_h_banks slices of that group fire in parallel; other groups have csb
#     deasserted.
#   - Example: 1024-bit word, 2048 words, 4h x 2v → eight 256b x 1024w macros
#   - Use case: wide words that are ALSO too deep for a single bank, where a
#     purely horizontal split would leave each macro over OpenRAM's row limit.
banking_mode = "vertical"

# Read ONLY when banking_mode == "mixed". Both must be powers of 2 and their
# product must equal num_banks.
#   num_h_banks -> word-width slices    (word_size must divide evenly)
#   num_v_banks -> address-space groups (num_words must divide evenly)
num_h_banks = 1
num_v_banks = 1

# ==============================================================================
# Technology Configuration
# ==============================================================================

# Process technology node
# Available options:
#   - "freepdk45"    : 45nm predictive PDK (most tested)
#   - "sky130"       : SkyWater 130nm open-source PDK
#   - "gf180mcu"     : GlobalFoundries 180nm mixed-signal PDK
#   - "scn4m_subm"   : MOSIS 0.5um scalable CMOS (4-metal)
#   - "scn3me_subm"  : MOSIS 0.8um scalable CMOS (3-metal)
tech_name = "freepdk45"

# Use conda for dependency management (set to False to skip conda installation)
use_conda = False

# ==============================================================================
# Advanced Options (Optional)
# ==============================================================================

# Number of parallel threads for generation (default: 4)
# Increase for faster generation on multi-core systems
num_threads = 4

# Performance optimizations (uncomment to enable)
# These make generation faster but may reduce accuracy

# analytical_delay = True        # Use fast analytical delay models (no SPICE)
# use_pex = False                # Disable parasitic extraction (faster)
# check_lvsdrc = False           # Skip DRC/LVS checks (faster iteration)
# trim_netlist = True            # Remove unused subcircuits from netlist

# ==============================================================================
# Post-Processing Configuration
# ==============================================================================

# Technology library path for Synopsys tools (NDM generation)
# Update this path to match your technology library location
# Only needed if you plan to run run_post_process.sh
tech_lib_path = "/path/to/your/tech/lib/NangateOpenCellLibrary.ndm"

# PVT corners to process during post-generation
# Format: <corner>_<voltage>_<temp>
# Multiple corners separated by spaces
# 
# Common corners:
#   TT_1p0V_25C    : Typical-Typical, 1.0V, 25°C (nominal)
#   FF_1p1V_125C   : Fast-Fast, 1.1V, 125°C (best case)
#   SS_0p9V_m40C   : Slow-Slow, 0.9V, -40°C (worst case)
#
# Example with multiple corners:
# pvt_corners = "TT_1p0V_25C FF_1p1V_125C SS_0p9V_m40C"
pvt_corners = "TT_1p0V_25C"

# ==============================================================================
# Auto-Generated Settings (Do Not Edit)
# ==============================================================================

# SRAM instance name (auto-generated from parameters)
# Suffix: '<N>v' vertical (default), '<N>h' horizontal, '<H>h<V>v' mixed
if banking_mode == "mixed":
    _banking_suffix = f"{num_h_banks}h{num_v_banks}v"
elif banking_mode == "horizontal":
    _banking_suffix = f"{num_banks}h"
else:
    _banking_suffix = f"{num_banks}v"
sram_name = f"sram_{word_size}x{num_words}_{_banking_suffix}"

# Output directory for generated files
output_path = "./outputs"

# ==============================================================================
# Example Configurations
# ==============================================================================
# Uncomment one of these example configurations or create your own

# --- Small Cache / Register File ---
# word_size = 32
# num_words = 32
# num_banks = 1

# --- Medium SRAM ---
# word_size = 64
# num_words = 256
# num_banks = 1

# --- Large SRAM ---
# word_size = 128
# num_words = 1024
# num_banks = 2
# banking_mode = "vertical"

# --- Very Large Multi-Bank SRAM ---
# word_size = 128
# num_words = 2048
# num_banks = 4
# banking_mode = "vertical"

# --- Wide-Word High-Performance SRAM (Horizontal Banking) ---
# word_size = 1024
# num_words = 2048
# num_banks = 8
# banking_mode = "horizontal"  # Bit-slicing, no mux latency

# --- Wide AND Deep SRAM (Mixed 2-D Banking) ---
# Eight 256b x 1024w macros: the word is split 4 ways, the depth 2 ways.
# word_size = 1024
# num_words = 2048
# num_banks = 8            # must equal num_h_banks * num_v_banks
# banking_mode = "mixed"
# num_h_banks = 4          # word-width slices
# num_v_banks = 2          # address-space groups