SPRUIM2H May 2020 – October 2023 AM2431 , AM2432 , AM2434 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442
Table 6-345 shows the default M4F 32b memory map view. Without enabling RAT function, M4F can’t access majority of the peripherals on the SoC level. From M4F point of view, only the address 0x6000_0000 to 0xDFFF_FFFF are sent to SoC level. Without RAT remapping the address, those transactions can only access various memory end points, such as flash, on-chip SRAM and DDR. In addition, M4F is not able to access the following memory region since these are beyond 4GB address space.
The RAT block for Blazar M4F supports 16 regions and there are many different ways to program those regions. It is recommended to configure the first 4 RAT regions to allow M4F access majority of the peripherals in the SoC and use the rest 12 regions to program the access to various memory end points based on the need.
Base | Size | translated address | Address remapping | |
---|---|---|---|---|
RAT region 0 | 0x6000_0000 | 256MB | 0x0000_0000 | Re-map the address range from 0x6000_0000 to 0x6FFF_FFFF to 0x0000_0000 to 0x0FFF_FFFF |
RAT region 1 | 0x7000_0000 | 256MB | 0x2000_0000 | Re-map the address range from 0x7000_0000 to 0x7FFF_FFFF to 0x2000_0000 to 0x2FFF_FFFF |
RAT region 2 | 0x8000_0000 | 256MB | 0x3000_0000 | Re-map the address range from 0x8000_0000 to 0x8FFF_FFFF to 0x3000_0000 to 0x3FFF_FFFF |
RAT region 3 | 0x9000_0000 | 256MB | 0x4000_0000 | Re-map the address range from 0x9000_0000 to 0x9FFF_FFFF to 0x4000_0000 to 0x4FFF_FFFF |
RAT region 4 | 0xA000_0000 | 2MB | 0x7000_0000 | Re-map the M4F address range from 0x9000_0000 to 0x901F_FFFF to 0x7000_0000 to 0x701F_FFFF ( on-chip SRAM) |
M4F can use address 0xA000_0000 to 0xDFFF_FFFF to access various memory end point on the SoC level such as:
But due to the limitation of the M4F 32b address window, it is not possible that M4F access the full SoC address map at the same time. The above RAT configuration can guarantee that M4F can access all the peripherals in SoC, but it has limited access to the memory end point. User can partition the M4F address window and only program RAT configuration to allow M4F accessing a limited memory region based on need.