Warning: this is dirty working draft version and is subject to change in future.

Allocating channels (in bus layers, etc)

   1 struct resource *gpdma_alloc_channel(const char *name, int chno)

Allocated a channel chno on engine named name (eg. edma0)

   1 int gpdma_release_channel(struct resource *rv)

Frees previously allocated channel.

Allocating transfers and starting DMA operations

   1 gpdma_transfer_t gpdma_alloc_transfer(struct resource *rv);

Allocates a new transfer structure, which will be used on engine and channel represented by rv. Transfer can be reused once completed.

   1 void gpdma_free_transfer(gpdma_transfer_t xfer);

Frees transfer xfer.

   1 void *gpdma_program_transfer(gpdma_transfer_t xfer);

Programs transfer xfer on channel described by res. This function returns a cookie of type void * which will be used to reference this DMA operation in future.

   1 int gpdma_start_transfer(void *cookie);

Starts previously programmed transfer. Returns 0 on success, nonzero on error.

   1 int gpdma_stop_transfer(void *cookie);

Stops previously started transfer. Returns 0 on success, nonzero on error. In particular, it can return ENOTSUP if stopping transfers is not supported.

Setting up transfers, buffers, etc

   1 int gpdma_setup_buffer_raw(gpdma_transfer_t xfer, int buffer, bus_addr_t addr, bus_size_t length)

Sets buffer of xfer pointing to physical memory address addr with length size.

   1 int gpdma_setup_buffer_virt(gpdma_transfer_t xfer, int buffer, void *p, size_t length);

Sets buffer of xfer pointing to virtual memory address (in KVA) p with length size.

   1 int gpdma_setup_buffer_uio(gpdma_transfer_t xfer, int buffer, struct uio *uio);

TODO describe

   1 void gpdma_set_transfer_func(gpdma_transfer_t xfer, int func)
   2 void gpdma_set_transfer_link(gpdma_transfer_t xfer, dmae_transfer_t next);
   3 void gpdma_set_transfer_callback(gpdma_transfer_t xfer, dmae_callback_t cb, void *arg);
   4 void gpdma_set_transfer_flags(gpdma_transfer_t xfer, int flags);
   6 int gpdma_get_buffer_layout(gpdma_transfer_t xfer, int buffer);
   7 void gpdma_set_buffer_layout(gpdma_transfer_t xfer, int buffer, int layout);
   8 void gpdma_set_buffer_stride(gpdma_transfer_t xfer, int buffer, int width, int spacing);
   9 void gpdma_set_buffer_fifo_width(gpdma_transfer_t xfer, int buffer, int width);

TODO describe

SOC2010JakubKlama/KernelAPI (last edited 2010-07-21 09:16:43 by JakubKlama)