Re: [EXT] Re: [V3 2/2] dmaengine: fsl-dpaa2-qdma: Add NXP dpaa2 qDMA controller driver for Layerscape SoCs

From: Vinod Koul
Date: Thu Jun 13 2019 - 11:35:40 EST


On 10-06-19, 09:51, Peng Ma wrote:

> >> + goto err;
> >> +
> >> + comp_temp->fl_virt_addr =
> >> + (void *)((struct dpaa2_fd *)
> >> + comp_temp->fd_virt_addr + 1);
> >
> >casts and pointer math, what could go wrong!! This doesnt smell right!
> >
> >> + comp_temp->fl_bus_addr = comp_temp->fd_bus_addr +
> >> + sizeof(struct dpaa2_fd);
> >
> >why not use fl_virt_addr and get the bus_address?
> What you mean is I should use virt_to_phys to get the bus_address?

Yes instead of maintaining both pointers, just use one and then when
required use one to get other. For bus address I would prefer
dma_map_single rather than virt_to_phys()
--
~Vinod