2021-11-12 12:29 AM
I'm using a STM32H747 DISCO boad and I just want to use the M4 CPU. When start, the M7 configs the Clock and does nothing since then. There is only a simple case running on the M4 CPU. The case takes 200ms on M4 while it took only 20ms on a Risc-v@300Mhz CPU.
I use the "-O2" and hardfloat during compiling. But I have no idea what should I do next.
Any Ideas?
The codes are arrays multiply operation with data of float type.
Solved! Go to Solution.
2021-11-14 06:08 PM
Turns out I was using the AXISRAM implicitly allocated to M7. Now It is much faster. But The Dhrystone is 0.37 DMIPS/MHz, which is still not a good number for me. The CPU clock is 200Mhz and ahb is the same.
2021-11-12 02:17 AM
Are you sure that the compiler uses hard fp and issues floating point instructions? M4 is single precision only? What is the M4 clock?
2021-11-14 06:08 PM
Turns out I was using the AXISRAM implicitly allocated to M7. Now It is much faster. But The Dhrystone is 0.37 DMIPS/MHz, which is still not a good number for me. The CPU clock is 200Mhz and ahb is the same.
2021-12-01 02:40 PM
For M4 core to run at decent speeds from the FLASH, one has to enable the ART.