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

From: Jernej Škrabec
Date: Thu Apr 28 2022 - 01:34:31 EST


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@xxxxxxxxxxxx>

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

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);