A Beginner's Guide to SSD Firmware (2023) [Thirumalai] [9781484298879]

Table of Contents
About the Author
About the Technical Reviewer
Chapter 1: Introduction to SSD Firmware
	What Is SSD?
	Summary
Chapter 2: Understanding the Role of Firmware in SSDs
	What Is Firmware?
	Summary
Chapter 3: The History and Evolution of SSD Firmware
	History
	Summary
Chapter 4: Basics of Flash Memory
	Memory Types
		NOR Flash Memory
			Characteristics of NOR Flash Memory
			NOR Memory Architecture
		NAND Flash Memory
			NAND Memory Architecture
		Similarities
		Differences
	A Flash Memory Cell
	NAND Memory Organization
		Addressing
	Erase
	Write
	Read
	Program/Erase Cycle (P/E Cycle)
	Summary
Chapter 5: 3D Vertical NAND
	Evolution of 3D Vertical NAND Technology
	Unlocking New Possibilities with Vertical NAND Architecture
	Advantages of 3D Vertical NAND
	Applications of 3D Vertical NAND
	Understanding 3D Vertical NAND Architecture
		Layers and Pages
		Charge Trapping Technology
		Bit Line and Word Line Architecture
		Control and Decoding Circuits
		Memory Cell Size and Density in 3D Vertical NAND Flash Memory Technology
	Understanding NAND Cell Types Supported: SLC, MLC, and TLC (QLC)
		SLC
		MLC
	TLC
	Read and Write Operations in 3D Vertical NAND
	Erasing MLC 3D vertical NAND block
	Endurance and Data Retention Capabilities
	Speed and Efficiency Compared to 2D Planar NAND
	Advancements in Storage Capacity with 3D Vertical NAND
	Summary
Chapter 6: Basic Understanding of NAND Flash Interface
	Basic NAND IO Interfacing Pin Details
	NAND Flash Interface Basics
	Open NAND Flash Interface (ONFI)
	Toggle Mode Interface
	Command Cycles for NAND Flash Operations
	Addressing
		Column Address
		Row Address
		Addressing Functions
		Address Cycle Order
		Handling Unused Bits
			Address Limitations
			Valid Address Range
			Address Validation
	NAND Flash Commands
		RESET Operation
		READ ID Operation
		READ STATUS Operation
	READ STATUS Response
		ERASE Operation
	PROGRAM Operations
	READ Operation
	RANDOM DATA READ Operation
	Typical NAND Packet Structure
	PAGE READ CACHE MODE Operation
	PROGRAM PAGE CACHE Operation
	Advanced Command Sets
	Address Input Restrictions for Multi-Plane Operations
	Multi-plane Read
	MULTI- PLANE RANDOM CACHE READ Operation
	Multi Plane Program Operation
	Multi Plane Cache Program Operation
	Multi Block Erase Operation
	Summary
Chapter 7: Common SSD Firmware Features
	Significance of Garbage Collection in SSDs
	Types of Garbage Collection Strategies
		Full Garbage Collection
		Partial Garbage Collection
		Dynamic Garbage Collection
		Error-Triggered Garbage Collection
		Garbage Collection Read Process
	Retrieving Valid Data during Compaction
	Handling Incomplete or Interrupted Reads
	Address Translation during Compaction Reads
	Writing Data during Compaction
	Address Mapping and Updating
	Managing Block Erasure and Wear-Leveling
	Handling Unexpected Power-Off Conditions in Garbage Collection
		Ensuring Data Consistency during Power Loss
		Write Journaling and Recovery Mechanisms
		Managing Incomplete Compaction Operations
	Performance Considerations in Garbage Collection
		Impact of Compaction on SSD Performance
		Write Amplification and Its Effects
		Strategies to Minimize Performance Degradation
	Balancing Garbage Collection and Host Write Operations
		Understanding the Workload Characteristics
		Garbage Collection Prioritization
		Dynamic Resource Allocation
		Over-Provisioning
		Adaptive Garbage Collection
	Drawbacks of Garbage Collection and Minimizing Their Impact
		Write Amplification
		Performance Degradation
		Increased Power Consumption
		Impact on Endurance
	Other Concerns
		Data Retention
		Read Disturb
		Program Disturbance
		Write Amplification
		Over-provisioning
		Encryption
	Summary
Chapter 8: SSD Firmware Design Considerations
	Design Considerations
	Unexpected Shutdown
	Power-Loss Protection
		Power-Loss Design Considerations
		Best Practices for Optimizing and Maintaining SSD Firmware
	Summary
Chapter 9: Flash Translation Layer (FTL)
	Mapping Table
	Size of the Mapping Table
	Storing the Mapping Table in RAM
	Partial Loading of the Mapping Table
		Storage of Non-Loaded Mapping Entries
	Write/Update Operations and the Mapping Table
		Dirty Cache Buffer in RAM
			Write/Update Process with Dirty Cache Buffer
			Flush to NAND
	Mapping Table Management and Optimization
	Bad Block Management
	Factory Bad Block Assessment
		Bad Block Flash Address
		Recording Bad Block Flash Address
		Initial Bad Block Handling Flow
			Step 1: Power-Up and Mounting
			Step 2: Reading the NAND Flash
			Step 3: Identifying Bad Blocks
			Step 4: Updating Bad Block Bitmap
			Step 5: Skipping Bad Blocks
			Step 6: Error Handling (Optional)
	Used Bad Block Assessment
		Bad Block Skipping Strategy
		Bad Block Replacement Strategy
	Summary
Chapter 10: User Data Flow
	Write Path
	Read Path
	Summary
Chapter 11: Throttling
	Thermal Throttling
		Temperature Monitoring
		Throttling Mechanism
		Temperature Recovery
		Design Consideration
	Power Throttling
		Power Monitoring
		Throttling Mechanism
		Power Recovery
	Combined Throttling
		Synergistic Operation
		Priority Management
	Dynamic Performance Adjustments
		Workload Awareness
	Logging and Reporting
		Event Logging
		Health Monitoring
	Summary
Chapter 12: Exception Handling
	Read Errors
		Handling
	Program Errors
	Handling
	Program Abort
		Handling
	Erase Errors
		Handling
	Summary
Chapter 13: Performance
	Access Patterns and Test Workloads
	Workloads
	Host Interface
	Summary
Chapter 14: Debugging
	Summary
Chapter 15: Future Developments and Innovations in SSD Firmware
	Summary
Chapter 16: Closing
Bibliography
Index