On 13 April 2018 at 11:39, Vinod Koul <vinod.k...@intel.com> wrote:
> On Thu, Apr 12, 2018 at 07:30:01PM +0800, Baolin Wang wrote:
>> >> > what does block and transaction len refer to here
>> >> Our DMA has 3 transfer mode: transaction transfer, block transfer and
>> >> fragment transfer. One transaction transfer can contain several blocks
>> >> transfer, and each block can be set proper block step. One block can
>> >> contain several fragments transfer with proper fragment step. It can
>> >> generate interrupts when one transaction transfer or block transfer or
>> >> fragment transfer is completed if user set the interrupt type. So here
>> >> we should set the length for transaction transfer, block transfer and
>> >> fragment transfer.
>> > what are the max size these types support?
>> These types max size definition:
>> #define SPRD_DMA_FRG_LEN_MASK GENMASK(16, 0)
>> #define SPRD_DMA_BLK_LEN_MASK GENMASK(16, 0)
>> #define SPRD_DMA_TRSC_LEN_MASK GENMASK(27, 0)
> They are register defines. How many items or bytes do each type of txn
These macros are the max size definitions, for example one fragment
length can support to 0x1ffff bytes, one transaction transfer can
support to 0xfffffff.