Re: [PATCH] firmware: qcom: scm: add 32 bit iommu page table support

[Stephan Gerhold <stephan@gerhold.net>]

On Tue, Dec 31, 2019 at 10:37:04PM -0500, Brian Masney wrote:
> Add 32 bit implmentations of the functions
> __qcom_scm_iommu_secure_ptbl_size() and
> __qcom_scm_iommu_secure_ptbl_init() that are required by the qcom_iommu
> driver.
> 
> Signed-off-by: Brian Masney <masneyb@onstation.org>
> ---
>  drivers/firmware/qcom_scm-32.c | 32 ++++++++++++++++++++++++++++++--
>  1 file changed, 30 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/firmware/qcom_scm-32.c b/drivers/firmware/qcom_scm-32.c
> index 48e2ef794ea3..f149a85d36b0 100644
> --- a/drivers/firmware/qcom_scm-32.c
> +++ b/drivers/firmware/qcom_scm-32.c
> @@ -638,13 +638,41 @@ int __qcom_scm_restore_sec_cfg(struct device *dev, u32 device_id,
>  int __qcom_scm_iommu_secure_ptbl_size(struct device *dev, u32 spare,
>  				      size_t *size)
>  {
> -	return -ENODEV;
> +	int psize[2] = { 0, 0 };

I would use an explicit size (i.e. __le32) here.

> +	int ret;
> +
> +	ret = qcom_scm_call(dev, QCOM_SCM_SVC_MP,
> +			    QCOM_SCM_IOMMU_SECURE_PTBL_SIZE,
> +			    &spare, sizeof(spare), &psize, sizeof(psize));
> +	if (ret || psize[1])
> +		return ret ? ret : -EINVAL;
> +
> +	*size = psize[0];
> +
> +	return 0;
>  }
>  
>  int __qcom_scm_iommu_secure_ptbl_init(struct device *dev, u64 addr, u32 size,
>  				      u32 spare)
>  {
> -	return -ENODEV;
> +	struct msm_scm_ptbl_init {
> +		__le32 paddr;
> +		__le32 size;
> +		__le32 spare;
> +	} req;
> +	int ret, scm_ret = 0;
> +
> +	req.paddr = addr;
> +	req.size = size;
> +	req.spare = spare;

I'm not sure if there is actually anyone using qcom in BE mode (does
that even work?), but all the other methods in this file explicitly
convert using cpu_to_le32(), so this method should do the same :)

> +
> +	ret = qcom_scm_call(dev, QCOM_SCM_SVC_MP,
> +			    QCOM_SCM_IOMMU_SECURE_PTBL_INIT,
> +			    &req, sizeof(req), &scm_ret, sizeof(scm_ret));
> +	if (ret || scm_ret)
> +		return ret ? ret : -EINVAL;
> +
> +	return 0;
>  }
>  
>  int __qcom_scm_io_readl(struct device *dev, phys_addr_t addr,
> -- 
> 2.21.0
>