Re: [PATCH 2/5] iommu/sun50i: Support variants without an external reset

["Jernej Škrabec" <jernej.skrabec@gmail.com>]

Dne četrtek, 28. april 2022 ob 03:03:57 CEST je Samuel Holland napisal(a):
> The IOMMU in the Allwinner D1 SoC does not have an external reset line.
> 
> Only attempt to get the reset on hardware variants which should have one
> according to the binding. And switch from the deprecated function to the
> explicit "exclusive" variant.
> 
> Signed-off-by: Samuel Holland <samuel@sholland.org>

Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>

Best regards,
Jernej

> ---
> 
>  drivers/iommu/sun50i-iommu.c | 18 ++++++++++++++++--
>  1 file changed, 16 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iommu/sun50i-iommu.c b/drivers/iommu/sun50i-iommu.c
> index c54ab477b8fd..ec07b60016d3 100644
> --- a/drivers/iommu/sun50i-iommu.c
> +++ b/drivers/iommu/sun50i-iommu.c
> @@ -92,6 +92,10 @@
>  #define NUM_PT_ENTRIES			256
>  #define PT_SIZE				(NUM_PT_ENTRIES * 
PT_ENTRY_SIZE)
> 
> +struct sun50i_iommu_variant {
> +	bool has_reset;
> +};
> +
>  struct sun50i_iommu {
>  	struct iommu_device iommu;
> 
> @@ -905,9 +909,14 @@ static irqreturn_t sun50i_iommu_irq(int irq, void
> *dev_id)
> 
>  static int sun50i_iommu_probe(struct platform_device *pdev)
>  {
> +	const struct sun50i_iommu_variant *variant;
>  	struct sun50i_iommu *iommu;
>  	int ret, irq;
> 
> +	variant = of_device_get_match_data(&pdev->dev);
> +	if (!variant)
> +		return -EINVAL;
> +
>  	iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL);
>  	if (!iommu)
>  		return -ENOMEM;
> @@ -947,7 +956,8 @@ static int sun50i_iommu_probe(struct platform_device
> *pdev) goto err_free_group;
>  	}
> 
> -	iommu->reset = devm_reset_control_get(&pdev->dev, NULL);
> +	if (variant->has_reset)
> +		iommu->reset = devm_reset_control_get_exclusive(&pdev-
>dev, NULL);
>  	if (IS_ERR(iommu->reset)) {
>  		dev_err(&pdev->dev, "Couldn't get our reset line.\n");
>  		ret = PTR_ERR(iommu->reset);
> @@ -987,8 +997,12 @@ static int sun50i_iommu_probe(struct platform_device
> *pdev) return ret;
>  }
> 
> +static const struct sun50i_iommu_variant sun50i_h6_iommu = {
> +	.has_reset = true,
> +};
> +
>  static const struct of_device_id sun50i_iommu_dt[] = {
> -	{ .compatible = "allwinner,sun50i-h6-iommu", },
> +	{ .compatible = "allwinner,sun50i-h6-iommu", .data = 
&sun50i_h6_iommu },
>  	{ /* sentinel */ },
>  };
>  MODULE_DEVICE_TABLE(of, sun50i_iommu_dt);