• Shawn Guo's avatar
    dmaengine: mxs-dma: add dma support for i.MX23/28 · a580b8c5
    Shawn Guo authored
    This patch adds dma support for Freescale MXS-based SoC i.MX23/28,
    including apbh-dma and apbx-dma.
    
    * apbh-dma and apbx-dma are supported in the driver as two mxs-dma
      instances.
    
    * apbh-dma is different between mx23 and mx28, hardware version
      register is used to differentiate.
    
    * mxs-dma supports pio function besides data transfer.  The driver
      uses dma_data_direction DMA_NONE to identify the pio mode, and
      steals sgl and sg_len to get pio words and numbers from clients.
    
    * mxs dmaengine has some very specific features, like sense function
      and the special NAND support (nand_lock, nand_wait4ready).  These
      are too specific to implemented in generic dmaengine driver.
    
    * The driver refers to imx-sdma and only a single descriptor is
      statically assigned to each channel.
    Signed-off-by: default avatarShawn Guo <shawn.guo@freescale.com>
    Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
    a580b8c5
mxs-dma.c 17.9 KB