On-chip Memory (Cache, Scratchpad) Integration On-chip memory (cache or scratchpad) integration plays a crucial role in System-on-Chip (SoC) design by pr...
On-chip memory (cache or scratchpad) integration plays a crucial role in System-on-Chip (SoC) design by providing a high-performance memory layer for the SoC components. It acts as an intermediate memory for the SoC, reducing access times and improving system performance.
Cache
A cache is a small, fast memory integrated directly onto the SoC chip.
It stores frequently accessed data from the main memory (RAM or DRAM).
The cache typically has a fixed size and limited capacity.
Cache miss penalties occur when data is requested by the SoC but is not in the cache.
Scratchpad
A scratchpad is a larger, non-volatile memory integrated onto the SoC chip.
It is used for long-term storage of data, such as configurations, settings, and large datasets.
The scratchpad has a higher capacity than the cache, allowing for more data to be stored.
While access times for scratchpad data are slower than cache data, they are much faster than RAM or DRAM.
Integration
The cache and scratchpad are integrated with the SoC's memory controller through a control interface.
The controller manages access to both memories, ensuring that they operate in synchronization.
The cache can be programmed to hold specific data patterns, while the scratchpad is typically used as a volatile memory.
Benefits of Cache and Scratchpad Integration
Reduced access times for SoC components.
Improved performance and reduced power consumption.
Increased memory capacity and flexibility.
Protection against memory failures and system crashes.
Examples
The L1 cache in a CPU is an example of a cache integrated onto the SoC chip.
Some SoCs have dedicated scratchpads for storing operating system and boot code