STM32_DMA_SFCR_FTH_MASK
chan->chan_reg.dma_sfcr &= ~STM32_DMA_SFCR_FTH_MASK;
chan->chan_reg.dma_sfcr |= FIELD_PREP(STM32_DMA_SFCR_FTH_MASK, fifoth);
desc->sg_req[i].chan_reg.dma_sfcr |= FIELD_PREP(STM32_DMA_SFCR_FTH_MASK, threshold);
chan->chan_reg.dma_sfcr &= ~STM32_DMA_SFCR_FTH_MASK;
chan->chan_reg.dma_sfcr |= FIELD_PREP(STM32_DMA_SFCR_FTH_MASK, fifoth);