| Message ID | 1491301105-5274-10-git-send-email-sricharan@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On 04/04/17 11:18, Sricharan R wrote: > This is an equivalent to the DT's handling of the iommu master's probe > with deferred probing when the corrsponding iommu is not probed yet. > The lack of a registered IOMMU can be caused by the lack of a driver for > the IOMMU, the IOMMU device probe not having been performed yet, having > been deferred, or having failed. > > The first case occurs when the firmware describes the bus master and > IOMMU topology correctly but no device driver exists for the IOMMU yet > or the device driver has not been compiled in. Return NULL, the caller > will configure the device without an IOMMU. > > The second and third cases are handled by deferring the probe of the bus > master device which will eventually get reprobed after the IOMMU. > > The last case is currently handled by deferring the probe of the bus > master device as well. A mechanism to either configure the bus master > device without an IOMMU or to fail the bus master device probe depending > on whether the IOMMU is optional or mandatory would be a good > enhancement. I think we really have caught everything now... Reviewed-by: Robin Murphy <robin.murphy@arm.com> > Tested-by: Hanjun Guo <hanjun.guo@linaro.org> > [Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure > called multiple times for same device] > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Signed-off-by: Sricharan R <sricharan@codeaurora.org> > --- > > [V10] Added Lorenzo's ACPI fix for coherent_dma_mask overflow > and the fix for dma_configure getting called more than > once for the same device. > > drivers/acpi/arm64/iort.c | 33 ++++++++++++++++++++++++++++++++- > drivers/acpi/scan.c | 11 ++++++++--- > drivers/base/dma-mapping.c | 2 +- > include/acpi/acpi_bus.h | 2 +- > include/linux/acpi.h | 7 +++++-- > 5 files changed, 47 insertions(+), 8 deletions(-) > > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > index 3dd9ec3..e323ece 100644 > --- a/drivers/acpi/arm64/iort.c > +++ b/drivers/acpi/arm64/iort.c > @@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct device *dev, > const struct iommu_ops *ops = NULL; > int ret = -ENODEV; > struct fwnode_handle *iort_fwnode; > + struct iommu_fwspec *fwspec = dev->iommu_fwspec; > + > + /* > + * If we already translated the fwspec there > + * is nothing left to do, return the iommu_ops. > + */ > + if (fwspec && fwspec->ops) > + return fwspec->ops; > > if (node) { > iort_fwnode = iort_get_fwnode(node); > @@ -550,8 +558,17 @@ static const struct iommu_ops *iort_iommu_xlate(struct device *dev, > return NULL; > > ops = iommu_ops_from_fwnode(iort_fwnode); > + /* > + * If the ops look-up fails, this means that either > + * the SMMU drivers have not been probed yet or that > + * the SMMU drivers are not built in the kernel; > + * Depending on whether the SMMU drivers are built-in > + * in the kernel or not, defer the IOMMU configuration > + * or just abort it. > + */ > if (!ops) > - return NULL; > + return iort_iommu_driver_enabled(node->type) ? > + ERR_PTR(-EPROBE_DEFER) : NULL; > > ret = arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops); > } > @@ -625,12 +642,26 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev) > > while (parent) { > ops = iort_iommu_xlate(dev, parent, streamid); > + if (IS_ERR_OR_NULL(ops)) > + return ops; > > parent = iort_node_get_id(node, &streamid, > IORT_IOMMU_TYPE, i++); > } > } > > + /* > + * If we have reason to believe the IOMMU driver missed the initial > + * add_device callback for dev, replay it to get things in order. > + */ > + if (!IS_ERR_OR_NULL(ops) && ops->add_device && > + dev->bus && !dev->iommu_group) { > + int err = ops->add_device(dev); > + > + if (err) > + ops = ERR_PTR(err); > + } > + > return ops; > } > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index 1926918..2a513cc 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -1373,20 +1373,25 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) > * @dev: The pointer to the device > * @attr: device dma attributes > */ > -void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) > +int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) > { > const struct iommu_ops *iommu; > + u64 size; > > iort_set_dma_mask(dev); > > iommu = iort_iommu_configure(dev); > + if (IS_ERR(iommu)) > + return PTR_ERR(iommu); > > + size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); > /* > * Assume dma valid range starts at 0 and covers the whole > * coherent_dma_mask. > */ > - arch_setup_dma_ops(dev, 0, dev->coherent_dma_mask + 1, iommu, > - attr == DEV_DMA_COHERENT); > + arch_setup_dma_ops(dev, 0, size, iommu, attr == DEV_DMA_COHERENT); > + > + return 0; > } > EXPORT_SYMBOL_GPL(acpi_dma_configure); > > diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c > index 82bd45c..755a2b5 100644 > --- a/drivers/base/dma-mapping.c > +++ b/drivers/base/dma-mapping.c > @@ -368,7 +368,7 @@ int dma_configure(struct device *dev) > } else if (has_acpi_companion(dma_dev)) { > attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode)); > if (attr != DEV_DMA_NOT_SUPPORTED) > - acpi_dma_configure(dev, attr); > + ret = acpi_dma_configure(dev, attr); > } > > if (bridge) > diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h > index ef0ae8a..2a9a5de 100644 > --- a/include/acpi/acpi_bus.h > +++ b/include/acpi/acpi_bus.h > @@ -575,7 +575,7 @@ struct acpi_pci_root { > > bool acpi_dma_supported(struct acpi_device *adev); > enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev); > -void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr); > +int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr); > void acpi_dma_deconfigure(struct device *dev); > > struct acpi_device *acpi_find_child_device(struct acpi_device *parent, > diff --git a/include/linux/acpi.h b/include/linux/acpi.h > index 9b05886..79d06ef6 100644 > --- a/include/linux/acpi.h > +++ b/include/linux/acpi.h > @@ -762,8 +762,11 @@ static inline enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) > return DEV_DMA_NOT_SUPPORTED; > } > > -static inline void acpi_dma_configure(struct device *dev, > - enum dev_dma_attr attr) { } > +static inline int acpi_dma_configure(struct device *dev, > + enum dev_dma_attr attr) > +{ > + return 0; > +} > > static inline void acpi_dma_deconfigure(struct device *dev) { } > >
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 3dd9ec3..e323ece 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -543,6 +543,14 @@ static const struct iommu_ops *iort_iommu_xlate(struct device *dev, const struct iommu_ops *ops = NULL; int ret = -ENODEV; struct fwnode_handle *iort_fwnode; + struct iommu_fwspec *fwspec = dev->iommu_fwspec; + + /* + * If we already translated the fwspec there + * is nothing left to do, return the iommu_ops. + */ + if (fwspec && fwspec->ops) + return fwspec->ops; if (node) { iort_fwnode = iort_get_fwnode(node); @@ -550,8 +558,17 @@ static const struct iommu_ops *iort_iommu_xlate(struct device *dev, return NULL; ops = iommu_ops_from_fwnode(iort_fwnode); + /* + * If the ops look-up fails, this means that either + * the SMMU drivers have not been probed yet or that + * the SMMU drivers are not built in the kernel; + * Depending on whether the SMMU drivers are built-in + * in the kernel or not, defer the IOMMU configuration + * or just abort it. + */ if (!ops) - return NULL; + return iort_iommu_driver_enabled(node->type) ? + ERR_PTR(-EPROBE_DEFER) : NULL; ret = arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops); } @@ -625,12 +642,26 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev) while (parent) { ops = iort_iommu_xlate(dev, parent, streamid); + if (IS_ERR_OR_NULL(ops)) + return ops; parent = iort_node_get_id(node, &streamid, IORT_IOMMU_TYPE, i++); } } + /* + * If we have reason to believe the IOMMU driver missed the initial + * add_device callback for dev, replay it to get things in order. + */ + if (!IS_ERR_OR_NULL(ops) && ops->add_device && + dev->bus && !dev->iommu_group) { + int err = ops->add_device(dev); + + if (err) + ops = ERR_PTR(err); + } + return ops; } diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 1926918..2a513cc 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1373,20 +1373,25 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) * @dev: The pointer to the device * @attr: device dma attributes */ -void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) +int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) { const struct iommu_ops *iommu; + u64 size; iort_set_dma_mask(dev); iommu = iort_iommu_configure(dev); + if (IS_ERR(iommu)) + return PTR_ERR(iommu); + size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); /* * Assume dma valid range starts at 0 and covers the whole * coherent_dma_mask. */ - arch_setup_dma_ops(dev, 0, dev->coherent_dma_mask + 1, iommu, - attr == DEV_DMA_COHERENT); + arch_setup_dma_ops(dev, 0, size, iommu, attr == DEV_DMA_COHERENT); + + return 0; } EXPORT_SYMBOL_GPL(acpi_dma_configure); diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c index 82bd45c..755a2b5 100644 --- a/drivers/base/dma-mapping.c +++ b/drivers/base/dma-mapping.c @@ -368,7 +368,7 @@ int dma_configure(struct device *dev) } else if (has_acpi_companion(dma_dev)) { attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode)); if (attr != DEV_DMA_NOT_SUPPORTED) - acpi_dma_configure(dev, attr); + ret = acpi_dma_configure(dev, attr); } if (bridge) diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index ef0ae8a..2a9a5de 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -575,7 +575,7 @@ struct acpi_pci_root { bool acpi_dma_supported(struct acpi_device *adev); enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev); -void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr); +int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr); void acpi_dma_deconfigure(struct device *dev); struct acpi_device *acpi_find_child_device(struct acpi_device *parent, diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 9b05886..79d06ef6 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -762,8 +762,11 @@ static inline enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) return DEV_DMA_NOT_SUPPORTED; } -static inline void acpi_dma_configure(struct device *dev, - enum dev_dma_attr attr) { } +static inline int acpi_dma_configure(struct device *dev, + enum dev_dma_attr attr) +{ + return 0; +} static inline void acpi_dma_deconfigure(struct device *dev) { }