On 09/06/2013 12:12 PM, Archit Taneja wrote: > The primary function of VPDMA is to move data between external memory and > internal processing modules(in our case, VPE) that source or sink data. VPDMA is > capable of buffering this data and then delivering the data as demanded to the > modules as programmed. The modules that source or sink data are referred to as > clients or ports. A channel is setup inside the VPDMA to connect a specific > memory buffer to a specific client. The VPDMA centralizes the DMA control > functions and buffering required to allow all the clients to minimize the > effect of long latency times. > > Add the following to the VPDMA helper: > > - A data struct which describe VPDMA channels. For now, these channels are the > ones used only by VPE, the list of channels will increase when VIP(Video > Input Port) also uses the VPDMA library. This channel information will be > used to populate fields required by data descriptors. > > - Data structs which describe the different data types supported by VPDMA. This > data type information will be used to populate fields required by data > descriptors and used by the VPE driver to map a V4L2 format to the > corresponding VPDMA data type. > > - Provide VPDMA register offset definitions, functions to read, write and modify > VPDMA registers. > > - Functions to create and submit a VPDMA list. A list is a group of descriptors > that makes up a set of DMA transfers that need to be completed. Each > descriptor will either perform a DMA transaction to fetch input buffers and > write to output buffers(data descriptors), or configure the MMRs of sub blocks > of VPE(configuration descriptors), or provide control information to VPDMA > (control descriptors). > > - Functions to allocate, map and unmap buffers needed for the descriptor list, > payloads containing MMR values and scaler coefficients. These use the DMA > mapping APIs to ensure exclusive access to VPDMA. > > - Functions to enable VPDMA interrupts. VPDMA can trigger an interrupt on the > VPE interrupt line when a descriptor list is parsed completely and the DMA > transactions are completed. This requires masking the events in VPDMA > registers and configuring some top level VPE interrupt registers. > > - Enable some VPDMA specific parameters: frame start event(when to start DMA for > a client) and line mode(whether each line fetched should be mirrored or not). > > - Function to load firmware required by VPDMA. VPDMA requires a firmware for > it's internal list manager. We add the required request_firmware apis to fetch > this firmware from user space. > > - Function to dump VPDMA registers. > > - A function to initialize and create a VPDMA instance, this will be called by > the VPE driver with it's platform device pointer, this function will take care > of loading VPDMA firmware and returning a vpdma_data instance back to the VPE > driver. The VIP driver will also call the same init function to initialize it's > own VPDMA instance. > > Signed-off-by: Archit Taneja <archit@xxxxxx> Acked-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> Regards, Hans > --- > drivers/media/platform/ti-vpe/vpdma.c | 578 +++++++++++++++++++++++++++++ > drivers/media/platform/ti-vpe/vpdma.h | 155 ++++++++ > drivers/media/platform/ti-vpe/vpdma_priv.h | 119 ++++++ > 3 files changed, 852 insertions(+) > create mode 100644 drivers/media/platform/ti-vpe/vpdma.c > create mode 100644 drivers/media/platform/ti-vpe/vpdma.h > create mode 100644 drivers/media/platform/ti-vpe/vpdma_priv.h > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
