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

[Peng Ma]

Hi Vinod,

>-----Original Message-----
>From: Vinod Koul <vkoul@xxxxxxxxxx>
>Sent: 2019年6月13日 19:03
>To: Peng Ma <peng.ma@xxxxxxx>
>Cc: dan.j.williams@xxxxxxxxx; Leo Li <leoyang.li@xxxxxxx>;
>linux-kernel@xxxxxxxxxxxxxxx; dmaengine@xxxxxxxxxxxxxxx
>Subject: Re: [EXT] Re: [V3 2/2] dmaengine: fsl-dpaa2-qdma: Add NXP dpaa2
>qDMA controller driver for Layerscape SoCs
>
>Caution: EXT Email
>
>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()
[Peng Ma] ok, thanks, I have already send V4 for this series patch, Please review it in your spare time.
Patchwork link: https://patchwork.kernel.org/project/linux-dmaengine/list/?series=131767
Best Regars,
Peng
>--
>~Vinod