Hi,
I have one question regarding the Display driver in WinCE7.0BSP for AM387x.
According to the user's guide for version 2.3, there are "EnableDMABlts" and "EnableNeonBlts" as one of Keys for registry of Display driver. So I think display driver has a function of DMA BLT and Neon BLT. I would like to use these function. Do you know some information for API using these function?
Also I found some limitation in the source file "omap_dmablt.cpp". The below comment is written in it.
/*
DMAFill is only available with Socs that has SDMA, which has native support for color filling.
This feature can be disabled from Display driver register settings - "DMAFill". It is enabled by
default if this entry is not available display driver register file.
For EDMA, it is hard to implement this feature. The reasons are as follows:
a. When implemented in EDMA FIFO mode, if Acnt is set to the size of the color parameter,
and using AB sync mode, then Bcnt(16 bits number) is not big enough to fill the whole screen.
There is not evernt available to use multiple AB transfers, so Ccnt can only be set to 1.
b. To overcome the problem in (a), and use pre-allocated the 32 bytes buffer (for example),
it is hard to handle the case to fill color in a window which is not 32 bytes aligned. This is
very common on desktop operation.
*/
As you know, AM3874 has EDMA not SDMA. So I think DMA BLT can't be used with AM3874. Is my understanding right?
When I would like to increase the performance of 2D drawing, is "Neon BLT" function effective for 2D performance up?
I appreciate your quick reply.
Best regards,
Michi
