> -----Original Message----- > From: Lorenzo Pieralisi [mailto:lorenzo.pieralisi@xxxxxxx] > Sent: Tuesday, June 13, 2017 2:13 PM > To: Shameerali Kolothum Thodi > Cc: marc.zyngier@xxxxxxx; sudeep.holla@xxxxxxx; will.deacon@xxxxxxx; > robin.murphy@xxxxxxx; hanjun.guo@xxxxxxxxxx; Gabriele Paoloni; John > Garry; iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx; linux-arm- > kernel@xxxxxxxxxxxxxxxxxxx; linux-acpi@xxxxxxxxxxxxxxx; devel@xxxxxxxxxx; > Linuxarm; Wangzhou (B); Guohanjun (Hanjun Guo) > Subject: Re: [PATCH 2/2] iommu/arm-smmu-v3:Enable ACPI based HiSilicon > erratum 161010801 > > On Tue, Jun 13, 2017 at 12:48:29PM +0100, shameer wrote: > > The HiSilicon erratum 161010801 describes the limitation of HiSilicon > > platforms Hip06/Hip07 to support the SMMU mappings for MSI > transactions. > > > > On these platforms GICv3 ITS translator is presented with the deviceID > > by extending the MSI payload data to 64 bits to include the deviceID. > > Hence, the PCIe controller on this platforms has to differentiate the > > MSI payload against other DMA payload and has to modify the MSI > payload. > > This basically makes it difficult for this platforms to have a SMMU > > translation for MSI. > > > > This patch implements a ACPI table based quirk to reserve the hw msi > > regions in the smmu-v3 driver which means these address regions will > > not be translated and will be excluded from iova allocations. > > > > Signed-off-by: shameer <shameerali.kolothum.thodi@xxxxxxxxxx> > > --- > > drivers/iommu/arm-smmu-v3.c | 27 ++++++++++++++++++++++----- > > 1 file changed, 22 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu- > v3.c > > index abe4b88..2636c85 100644 > > --- a/drivers/iommu/arm-smmu-v3.c > > +++ b/drivers/iommu/arm-smmu-v3.c > > @@ -597,6 +597,7 @@ struct arm_smmu_device { > > u32 features; > > > > #define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0) > > +#define ARM_SMMU_OPT_RESV_HW_MSI (1 << 1) > > u32 options; > > > > struct arm_smmu_cmdq cmdq; > > @@ -1904,14 +1905,29 @@ static void arm_smmu_get_resv_regions(struct > device *dev, > > struct list_head *head) > > { > > struct iommu_resv_region *region; > > + struct arm_smmu_device *smmu; > > + struct iommu_fwspec *fwspec = dev->iommu_fwspec; > > int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; > > > > - region = iommu_alloc_resv_region(MSI_IOVA_BASE, > MSI_IOVA_LENGTH, > > - prot, IOMMU_RESV_SW_MSI); > > - if (!region) > > - return; > > + smmu = arm_smmu_get_by_fwnode(fwspec->iommu_fwnode); > > > > - list_add_tail(®ion->list, head); > > + if (smmu && (smmu->options & ARM_SMMU_OPT_RESV_HW_MSI) > && > > + dev_is_pci(dev)) { > > + int ret; > > + > > + ret = iort_iommu_its_get_resv_regions(dev, head); > > This should be made fwnode dependent, it makes precious little sense to call > IORT to reserve regions on a DT based platforms (I know the > ARM_SMMU_OPT_RESV_HW_MSI option is only selected in ACPI (?) but > comment applies regardless - have you prototyped a DT version too ?). Ok. I will add a check here. I don't have a DT version for now as ACPI is our top priority at the moment. Thanks, Shameer -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
