[PATCH v11 1/3] ACPI/IORT: Add msi address regions reservation helper

[Shameerali Kolothum Thodi]

Hi Lorenzo,

> -----Original Message-----
> From: Lorenzo Pieralisi [mailto:lorenzo.pieralisi at arm.com]
> Sent: Thursday, December 14, 2017 11:48 AM
> To: Shameerali Kolothum Thodi <shameerali.kolothum.thodi at huawei.com>
> Cc: robin.murphy at arm.com; marc.zyngier at arm.com; will.deacon at arm.com;
> joro at 8bytes.org; John Garry <john.garry at huawei.com>; xuwei (O)
> <xuwei5 at hisilicon.com>; Guohanjun (Hanjun Guo) <guohanjun at huawei.com>;
> iommu at lists.linux-foundation.org; linux-arm-kernel at lists.infradead.org; linux-
> acpi at vger.kernel.org; devicetree at vger.kernel.org; Linuxarm
> <linuxarm at huawei.com>
> Subject: Re: [PATCH v11 1/3] ACPI/IORT: Add msi address regions reservation
> helper
> 
> On Wed, Dec 13, 2017 at 11:58:28AM +0000, Shameer Kolothum wrote:
> > On some platforms msi parent address regions have to be excluded from
> > normal IOVA allocation in that they are detected and decoded in a HW
> > specific way by system components and so they cannot be considered normal
> > IOVA address space.
> >
> > Add a helper function that retrieves ITS address regions - the msi
> > parent - through IORT device <-> ITS mappings and reserves it so that
> > these regions will not be translated by IOMMU and will be excluded from
> > IOVA allocations. The function checks for the smmu model number and
> > only applies the msi reservation if the platform requires it.
> >
> > Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi at huawei.com>
> > ---
> >  drivers/acpi/arm64/iort.c        | 112
> +++++++++++++++++++++++++++++++++++++--
> >  drivers/irqchip/irq-gic-v3-its.c |   3 +-
> >  include/linux/acpi_iort.h        |   7 ++-
> >  3 files changed, 117 insertions(+), 5 deletions(-)
> 
> You need this additional hunk to make it compile on !CONFIG_IOMMU_API:

Oops..Sorry, missed that. If you are happy with the rest, I will make the below
change and sent out the v12(hopefully final).

Please let me know.

Thanks,
Shameer

> 
> -- >8 --
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index 3e0ce652c3e8..e2f7bddf5522 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -762,25 +762,6 @@ static int __maybe_unused __get_pci_rid(struct
> pci_dev *pdev, u16 alias,
>  	return 0;
>  }
> 
> -static __maybe_unused struct acpi_iort_node *iort_get_msi_resv_iommu(
> -						struct device *dev)
> -{
> -	struct acpi_iort_node *iommu;
> -	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
> -
> -	iommu = iort_get_iort_node(fwspec->iommu_fwnode);
> -
> -	if (iommu && (iommu->type == ACPI_IORT_NODE_SMMU_V3)) {
> -		struct acpi_iort_smmu_v3 *smmu;
> -
> -		smmu = (struct acpi_iort_smmu_v3 *)iommu->node_data;
> -		if (smmu->model ==
> ACPI_IORT_SMMU_V3_HISILICON_HI161X)
> -			return iommu;
> -	}
> -
> -	return NULL;
> -}
> -
>  static int arm_smmu_iort_xlate(struct device *dev, u32 streamid,
>  			       struct fwnode_handle *fwnode,
>  			       const struct iommu_ops *ops)
> @@ -807,6 +788,24 @@ static inline bool iort_iommu_driver_enabled(u8 type)
>  }
> 
>  #ifdef CONFIG_IOMMU_API
> +static struct acpi_iort_node *iort_get_msi_resv_iommu(struct device *dev)
> +{
> +	struct acpi_iort_node *iommu;
> +	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
> +
> +	iommu = iort_get_iort_node(fwspec->iommu_fwnode);
> +
> +	if (iommu && (iommu->type == ACPI_IORT_NODE_SMMU_V3)) {
> +		struct acpi_iort_smmu_v3 *smmu;
> +
> +		smmu = (struct acpi_iort_smmu_v3 *)iommu->node_data;
> +		if (smmu->model ==
> ACPI_IORT_SMMU_V3_HISILICON_HI161X)
> +			return iommu;
> +	}
> +
> +	return NULL;
> +}
> +
>  static inline const struct iommu_ops *iort_fwspec_iommu_ops(
>  				struct iommu_fwspec *fwspec)
>  {