Arria V GX configuation issues

Hello,

1- Most probably the corruption is due to NIOS II code is accidentally writing flash. Please check the pointers in your code.

a. The EPCS flash is memory-mapped via altera_avalon_epcs_flash_controller

b. There is risk when writing to memory-mapped region, the code interpreted as erase/write commands if done in specific sequence.

2- Using IORD_ALTERA_EPCQ_CONTROLLER_STATUS returns 0x20 does not corresponds to actual flash status register. Please try below:

a. The EPCQ controller in Quartus Standard does not directly exposed SPI-level operations like "read status register", instead, you need to use low-level flash driver that provides these operations. You need to include the EPCS Flash Driver. from this location <nios2_install>/components/altera_avalon_epcs_flash_controller.

b. use the "alt_epcs_flash_read_status_register()" function.

c. Use "alt_avalon_spi_command( )" with 0x05 to read Flash Status Register.

3- Protecting Flash from NIOS II writes

a. Avoid using "alt_lock_flash()" for permanent protection, please use WEL (Write Enable Latch) signal in your code:

i) every flash write or erase operation will require WEL to be set(via 0x06 WE command).

ii) if WEL is not set, write/erase will be ignored.

iii) WEL will be cleared automatically after each write/erase operation.

b. Avoid calling 0x06 (WE) unless in controlled condition in your code.

regards,

Farabi