| Message ID | 20191209180514.272727-4-jean-philippe@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
Hi Jean, On 12/9/19 7:05 PM, Jean-Philippe Brucker wrote: > For platform devices that support SubstreamID (SSID), firmware provides > the number of supported SSID bits. Restrict it to what the SMMU supports > and cache it into master->ssid_bits, which will also be used for PCI > PASID. > > Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> > --- > drivers/iommu/arm-smmu-v3.c | 13 +++++++++++++ > drivers/iommu/of_iommu.c | 6 +++++- > include/linux/iommu.h | 2 ++ > 3 files changed, 20 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index d4e8b7f8d9f4..837b4283b4dc 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -292,6 +292,12 @@ > > #define CTXDESC_CD_1_TTB0_MASK GENMASK_ULL(51, 4) > > +/* > + * When the SMMU only supports linear context descriptor tables, pick a > + * reasonable size limit (64kB). > + */ > +#define CTXDESC_LINEAR_CDMAX ilog2(SZ_64K / (CTXDESC_CD_DWORDS << 3)) > + > /* Convert between AArch64 (CPU) TCR format and SMMU CD format */ > #define ARM_SMMU_TCR2CD(tcr, fld) FIELD_PREP(CTXDESC_CD_0_TCR_##fld, \ > FIELD_GET(ARM64_TCR_##fld, tcr)) > @@ -638,6 +644,7 @@ struct arm_smmu_master { > u32 *sids; > unsigned int num_sids; > bool ats_enabled; > + unsigned int ssid_bits; > }; > > /* SMMU private data for an IOMMU domain */ > @@ -2571,6 +2578,12 @@ static int arm_smmu_add_device(struct device *dev) > } > } > > + master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits); > + > + if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB)) > + master->ssid_bits = min_t(u8, master->ssid_bits, > + CTXDESC_LINEAR_CDMAX); > + > group = iommu_group_get_for_dev(dev); > if (!IS_ERR(group)) { > iommu_group_put(group); > diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c > index 026ad2b29dcd..b3ccb2f7f1c7 100644 > --- a/drivers/iommu/of_iommu.c > +++ b/drivers/iommu/of_iommu.c > @@ -196,8 +196,12 @@ const struct iommu_ops *of_iommu_configure(struct device *dev, > if (err) > break; > } > - } > > + fwspec = dev_iommu_fwspec_get(dev); > + if (!err && fwspec) > + of_property_read_u32(master_np, "pasid-num-bits", > + &fwspec->num_pasid_bits); > + } This patch dedicates to platform devices however I fail to understand, at that stage, how/when do you retrieve/store the same max capability for PCI devices? > > /* > * Two success conditions can be represented by non-negative err here: > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index 3a113c5d7394..bd46775c3329 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -581,6 +581,7 @@ struct iommu_group *fsl_mc_device_group(struct device *dev); > * @ops: ops for this device's IOMMU > * @iommu_fwnode: firmware handle for this device's IOMMU > * @iommu_priv: IOMMU driver private data for this device > + * @num_pasid_bits: number of PASID bits supported by this device > * @num_ids: number of associated device IDs > * @ids: IDs which this device may present to the IOMMU > */ > @@ -589,6 +590,7 @@ struct iommu_fwspec { > struct fwnode_handle *iommu_fwnode; > void *iommu_priv; > u32 flags; > + u32 num_pasid_bits; > unsigned int num_ids; > u32 ids[1]; > }; > Besides, Reviewed-by: Eric Auger <eric.auger@redhat.com> Thanks Eric
Hi Eric, On Tue, Dec 17, 2019 at 12:05:18PM +0100, Auger Eric wrote: > > + fwspec = dev_iommu_fwspec_get(dev); > > + if (!err && fwspec) > > + of_property_read_u32(master_np, "pasid-num-bits", > > + &fwspec->num_pasid_bits); > > + } > This patch dedicates to platform devices however I fail to understand, > at that stage, how/when do you retrieve/store the same max capability > for PCI devices? For PCI devices, the max capability is only described by the PCIe PASID capability, not by firmware. Patch 13 deals with PCI by setting masted->ssid_bits from the PASID capability directly, ignoring fwspec->num_pasid_bits. > Besides, > > Reviewed-by: Eric Auger <eric.auger@redhat.com> Thanks! Jean
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index d4e8b7f8d9f4..837b4283b4dc 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -292,6 +292,12 @@ #define CTXDESC_CD_1_TTB0_MASK GENMASK_ULL(51, 4) +/* + * When the SMMU only supports linear context descriptor tables, pick a + * reasonable size limit (64kB). + */ +#define CTXDESC_LINEAR_CDMAX ilog2(SZ_64K / (CTXDESC_CD_DWORDS << 3)) + /* Convert between AArch64 (CPU) TCR format and SMMU CD format */ #define ARM_SMMU_TCR2CD(tcr, fld) FIELD_PREP(CTXDESC_CD_0_TCR_##fld, \ FIELD_GET(ARM64_TCR_##fld, tcr)) @@ -638,6 +644,7 @@ struct arm_smmu_master { u32 *sids; unsigned int num_sids; bool ats_enabled; + unsigned int ssid_bits; }; /* SMMU private data for an IOMMU domain */ @@ -2571,6 +2578,12 @@ static int arm_smmu_add_device(struct device *dev) } } + master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits); + + if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB)) + master->ssid_bits = min_t(u8, master->ssid_bits, + CTXDESC_LINEAR_CDMAX); + group = iommu_group_get_for_dev(dev); if (!IS_ERR(group)) { iommu_group_put(group); diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index 026ad2b29dcd..b3ccb2f7f1c7 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -196,8 +196,12 @@ const struct iommu_ops *of_iommu_configure(struct device *dev, if (err) break; } - } + fwspec = dev_iommu_fwspec_get(dev); + if (!err && fwspec) + of_property_read_u32(master_np, "pasid-num-bits", + &fwspec->num_pasid_bits); + } /* * Two success conditions can be represented by non-negative err here: diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 3a113c5d7394..bd46775c3329 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -581,6 +581,7 @@ struct iommu_group *fsl_mc_device_group(struct device *dev); * @ops: ops for this device's IOMMU * @iommu_fwnode: firmware handle for this device's IOMMU * @iommu_priv: IOMMU driver private data for this device + * @num_pasid_bits: number of PASID bits supported by this device * @num_ids: number of associated device IDs * @ids: IDs which this device may present to the IOMMU */ @@ -589,6 +590,7 @@ struct iommu_fwspec { struct fwnode_handle *iommu_fwnode; void *iommu_priv; u32 flags; + u32 num_pasid_bits; unsigned int num_ids; u32 ids[1]; };
For platform devices that support SubstreamID (SSID), firmware provides the number of supported SSID bits. Restrict it to what the SMMU supports and cache it into master->ssid_bits, which will also be used for PCI PASID. Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> --- drivers/iommu/arm-smmu-v3.c | 13 +++++++++++++ drivers/iommu/of_iommu.c | 6 +++++- include/linux/iommu.h | 2 ++ 3 files changed, 20 insertions(+), 1 deletion(-) -- 2.24.0