Which DSP to choose for calculating complex waveforms?

Question

Signal processing

Hello.
For the past few years, I have only worked with microcontrollers in strictly real time. Usually, for my tasks, some ARM with a frequency > 100 MHz in conjunction with an FPGA was enough.
Now my task is to form a complex waveform, and the calculation of the instantaneous frequency value should take place "on the fly". The actual system is DSP -> FPGA -> DAC or DSP -> DAC. The data refresh rate on the DAC must be at least 300 MHz. Accordingly, the DSP must be able to provide this. Calculations will most likely be without the use of floating point numbers.
Also on the DSP is the interface part (receiving data from an external device).
Because I didn’t work with DSP before, but now I find it difficult to choose it. What can you advise based on the conditions set?
Of course, I understand that such a brief description does not describe the complexity of the algorithms used, power consumption, the cost of the system as a whole, and many other aspects, but now I would like to know for myself what can theoretically suit my task, what level of entry for a particular DSP (with given that I more or less know microcontrollers on ARM), how difficult it is to develop on bare metal (I noticed that some DSPs are either on Linux or under some kind of RTOS), the availability of debugging tools and software for developing on Linux. In general, I want to get answers, where should I start.
So far, I am working on a variant with KeyStone from TI, containing ARM and C66xx cores (or rather 66AK2L06), as well as an option to perform all calculations on some fast FPGA with built-in cores and generally abandon the DSP. The choice of 66AK2L06 is due to the fact that it also has ARM cores, which can be assigned interface interactions.
Again, because did not work with DSP, the choice of 66AK2L06 may be wrong.

Answer 1

You didn't say anything about the bandwidth of the output signal processing, the 300 MHz DAC says nothing, since at such a frequency you can output both a mono frequency and a <150 MHz wideband signal.
You did not say about the type of processing and formation of a "complex signal", you can form it on the fly from large memory arrays using only DMA to transfer readings from memory to the DAC, or you may have to carry out complex filtering or calculation of output readings using mathematical formulas.
I would do everything on FPGA.