[PATCH 01/13] i3c: mipi-i3c-hci-pci: Set 64-bit DMA mask for Intel controllers

[Frank Li]

On Wed, Nov 12, 2025 at 12:03:27PM +0200, Adrian Hunter wrote:
> All Intel controllers support 64-bit DMA.  Set the DMA mask accordingly.
>
> This is needed only if there is no IOMMU configured, which is not
> recommended, but possible.
>
> Signed-off-by: Adrian Hunter <adrian.hunter at intel.com>
> ---
>  drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c b/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c
> index dd4484eff2f0..850fcec4cacf 100644
> --- a/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c
> +++ b/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c
> @@ -29,6 +29,7 @@ static int mipi_i3c_hci_pci_intel_init(struct pci_dev *pci)
>  {
>  	unsigned long timeout;
>  	void __iomem *priv;
> +	int ret;
>
>  	priv = devm_ioremap(&pci->dev,
>  			    pci_resource_start(pci, 0) + INTEL_PRIV_OFFSET,
> @@ -36,6 +37,10 @@ static int mipi_i3c_hci_pci_intel_init(struct pci_dev *pci)
>  	if (!priv)
>  		return -ENOMEM;
>
> +	ret = dma_set_mask_and_coherent(&pci->dev, DMA_BIT_MASK(64));
> +	if (ret)
> +		return ret;
>

Needn't check return value dma_set_mask_and_coherent(), it is always true
if mask >= 32

See Documentation/core-api/dma-api-howto.rst

commit f7ae20f2fc4e6a5e32f43c4fa2acab3281a61c81
Author: Frank Li <Frank.Li at nxp.com>
Date:   Mon Apr 1 13:41:59 2024 -0400

    docs: dma: correct dma_set_mask() sample code


Frank
>  	/* Assert reset, wait for completion and release reset */
>  	writel(0, priv + INTEL_PRIV_RESETS);
>  	timeout = jiffies + msecs_to_jiffies(10);
> --
> 2.51.0
>
>
> --
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