On 03-11-21, 16:33, Amelie Delaunay wrote: > From: Arnd Bergmann <arnd@xxxxxxxx> > > Using the % operator on a 64-bit variable is expensive and can > cause a link failure: > > arm-linux-gnueabi-ld: drivers/dma/stm32-dma.o: in function `stm32_dma_get_max_width': > stm32-dma.c:(.text+0x170): undefined reference to `__aeabi_uldivmod' > arm-linux-gnueabi-ld: drivers/dma/stm32-dma.o: in function `stm32_dma_set_xfer_param': > stm32-dma.c:(.text+0x1cd4): undefined reference to `__aeabi_uldivmod' > > As we know that we just want to check the alignment in > stm32_dma_get_max_width(), there is no need for a full division, and > using a simple mask is a faster replacement. > > Same in stm32_dma_set_xfer_param(), change this to only allow burst > transfers if the address is a multiple of the length. > stm32_dma_get_best_burst just after will take buf_len into account to fix > burst in case of misalignment. Applied, thanks -- ~Vinod
