Re: [PATCH] gpu: host1x: Do not setup DMA for virtual devices

[Jon Hunter <jonathanh@nvidia.com>]

On 14/03/2024 15:49, Thierry Reding wrote:
> From: Thierry Reding <treding@nvidia.com>
> 
> The host1x devices are virtual compound devices and do not perform DMA
> accesses themselves, so they do not need to be set up for DMA.
> 
> Ideally we would also not need to set up DMA masks for the virtual
> devices, but we currently still need those for legacy support on old
> hardware.
> 
> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
>   drivers/gpu/host1x/bus.c | 8 --------
>   1 file changed, 8 deletions(-)
> 
> diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
> index 783975d1384f..7c52757a89db 100644
> --- a/drivers/gpu/host1x/bus.c
> +++ b/drivers/gpu/host1x/bus.c
> @@ -351,11 +351,6 @@ static int host1x_device_uevent(const struct device *dev,
>   	return 0;
>   }
>   
> -static int host1x_dma_configure(struct device *dev)
> -{
> -	return of_dma_configure(dev, dev->of_node, true);
> -}
> -
>   static const struct dev_pm_ops host1x_device_pm_ops = {
>   	.suspend = pm_generic_suspend,
>   	.resume = pm_generic_resume,
> @@ -369,7 +364,6 @@ const struct bus_type host1x_bus_type = {
>   	.name = "host1x",
>   	.match = host1x_device_match,
>   	.uevent = host1x_device_uevent,
> -	.dma_configure = host1x_dma_configure,
>   	.pm = &host1x_device_pm_ops,
>   };
>   
> @@ -458,8 +452,6 @@ static int host1x_device_add(struct host1x *host1x,
>   	device->dev.bus = &host1x_bus_type;
>   	device->dev.parent = host1x->dev;
>   
> -	of_dma_configure(&device->dev, host1x->dev->of_node, true);
> -
>   	device->dev.dma_parms = &device->dma_parms;
>   	dma_set_max_seg_size(&device->dev, UINT_MAX);
>   


Tested-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>

Thanks!
Jon

-- 
nvpublic