During stress testing involving repeated startup and shutdown, a fatal error was encountered in the STM32F407 Ethernet (ETH) module.
The issue was observed during the startup phase, where a problem occurred in the ETH DMA. The DMASR register indicated a Fatal Bus Error.
The following are the ETH register values captured when the error occurred:
MACCR : 0x0200CE0C
MACFFR : 0x00000000
MACHTHR : 0x00000000
MACHTLR : 0x00000000
MACMIIAR : 0x000007D0
MACMIIDR : 0x00001058
MACFCR : 0x00000080
MACVLANTR : 0x00000000
MACRWUFFR : 0x00000000
MACPMTCSR : 0x00000000
MACDBGR : 0x00000000
MACSR : 0x00000000
MACIMR : 0x00000208
MACA0HR : 0x80000103
MACA0LR : 0x0AE18000
MACA1HR : 0x0000FFFF
MACA1LR : 0xFFFFFFFF
MACA2HR : 0x0000FFFF
MACA2LR : 0xFFFFFFFF
MACA3HR : 0x0000FFFF
MACA3LR : 0xFFFFFFFF
MMCCR : 0x00000000
MMCRIR : 0x00000000
MMCTIR : 0x00000000
MMCRIMR : 0x00020060
MMCTIMR : 0x0020C000
MMCTGFSCCR : 0x00000000
MMCTGFMSCCR : 0x00000000
MMCTGFCR : 0x00000001
MMCRFCECR : 0x00000000
MMCRFAECR : 0x00000000
MMCRGUFCR : 0x00000003
PTPTSCR : 0x00002000
PTPSSIR : 0x00000000
PTPTSHR : 0x00000000
PTPTSLR : 0x00000000
PTPTSHUR : 0x00000000
PTPTSLUR : 0x00000000
PTPTSAR : 0x00000000
PTPTTHR : 0x00000000
PTPTTLR : 0x00000000
PTPTSSR : 0x00000000
DMABMR : 0x02C12080
DMATPDR : 0x00000000
DMARPDR : 0x00000000
DMARDLAR : 0x20005554
DMATDLAR : 0x200055F4
DMASR : 0x0189A4C2
DMAOMR : 0x02202006
DMAIER : 0x000020C1
DMAMFBOCR : 0x00002773
DMARSWTR : 0x00000000
DMACHTDR : 0x2000561C
DMACHRDR : 0x20005554
DMACHTBAR : 0x00000000
DMACHRBAR : 0x20004F48␍␊
