For production reason, using openocd with sflash_write.tcl to program external flash is slow. (67KiB /s)
We tried enabling MCU PLL clock and increasing adapter_khz to 8000 and achieved 140KiB/s.
(more adapter_khz doesn't help)
Is there any other parameter can be tuned for faster SPI flash programming ?
ps. we are working on STM32 platform. but similar issue also apply to 439x platform.
For the STM family you can preprogram the sflash before mounting
you don't need to use openocd
We have support for SPI dma coming in the next sdk but it will only help on speeding up sflash that supports 128 or 256 byte writes