Dma troubles

Hi,

I’m experienceing trouble with adresse when i’m configuring DMA a
transfert. I use a ppc board (Powerquick3) and a self made Pci card.

  1. I’m allocating memory with mmap

V_P_LogicalAddr =(ULONG) mmap(
0,
1024,
PROT_READ|PROT_WRITE|PROT_NOCACHE,
MAP_PHYS|MAP_ANON,
NOFD,
0 );
and i retrieve the physical adresse with mem offset.
mem_offset (V_P_LogicalAddr,NOFD,1024,&V_PAddr,NULL);
2) i write this adresse on the dma register on my pci board.(write size
and start to the dma ctl)

  1. the dma start but the pci board read nothing (but the right size)

  2. a try to whatch the value of the CpuBmstrTranslation value in the
    pci_dev_info structure but its equal to 0 !!!

I think i forgot something but what ?? have you got a idea ??

have a nice day :wink:



Benjamin Ferlicot
bfe@ixsea.com

newb on qnx os (also in ppc )