5.3.1. General ECC Design Considerations
Each RAM in the HPS subsystem has its own ECC controller with a unique set of
features and requirements. However, there are general system integration design
issues that you should consider.
5.3.2. System-Level ECC Control, Status and Interrupt Management
The System Manager contains a set of ECC-related registers for system-level control
and status for all the ECC controllers in the HPS subsystem. ECC-related interrupts are
also managed through this set of registers.
Related Information
•
System Manager - Cyclone V Hard Processor System Technical Reference Manual
•
System Manager - Arria V Hard Processor System Technical Reference Manual
5.3.3. ECC for L2 Cache Data Memory
The L2 cache memory is ECC protected, while the tag RAMs are parity protected. L2
cache ECC is enabled through a control register in the System Manager.
For details about the L2 cache ECC controller, refer to the following sections in the
"Cortex-A9 Microprocessor Unit Subsystem" chapter of the appropriate Hard Processor
System Technical Reference Manual:
•
“Single Event Upset Protection”
•
“L2 Cache Controller Address Map for Cyclone V” or "L2 Cache Controller Address
Map for Arria V"
GUIDELINE: The L1 and L2 cache must be configured as write-back and
write-allocate for any cacheable memory region with ECC enabled.
For BSPs supported by the Intel SoC FPGA EDS, you can configure your BSP for ECC
support with the bsp-editor utility.
For bare metal firmware, refer to "L2 Cache Controller Address Map" in the "Cortex-A9
Microprocessor Unit Subsystem" chapter of the appropriate Hard Processor System
Technical Reference Manual.
GUIDELINE: Cache-coherent accesses through the L3 interconnect using the
ACP must perform 64-bit wide, 64-bit aligned write accesses when ECC is
enabled in the L2 Cache Controller
Enabling ECC does not affect the performance of the L2 cache, but accesses using the
ACP must be 64-bit wide, 64-bit aligned in memory. This includes FPGA masters
accessing the ACP over the FPGA-to-HPS Bridge. For a list of possible combinations of
bridge width and FPGA master width, alignment and burst size and length, refer to
"FPGA-to-HPS Access to ACP" in the "HPS-FPGA Bridges" chapter of the appropriate
Hard Processor System Technical Reference Manual.
Related Information
•
Cyclone V Hard Processor System Technical Reference Manual
•
Arria V Hard Processor System Technical Reference Manual
5. Embedded Software Design Guidelines for SoC FPGAs
AN-796 | 2018.06.18
AN 796: Cyclone V and Arria V SoC Device Design Guidelines
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