Hi Mark, On Tue, 17 Jan 2023 at 15:04, Mark Kettenis <kette...@openbsd.org> wrote: > > In order to support IOMMUs in non-bypass mode we need device ops > to map and unmap DMA memory. The map operation enters a mapping > for a region specified by CPU address and size into the translation > table of the IOMMU and returns a DMA address suitable for > programming the device to do DMA. The unmap operation removes > this mapping from the translation table of the IOMMU. > > Signed-off-by: Mark Kettenis <kette...@openbsd.org> > --- > drivers/iommu/iommu-uclass.c | 28 ++++++++++++++++++++++++++++ > include/dm/device.h | 3 +++ > include/iommu.h | 24 ++++++++++++++++++++++++ > 3 files changed, 55 insertions(+) > > diff --git a/drivers/iommu/iommu-uclass.c b/drivers/iommu/iommu-uclass.c > index ed917b3c3e..f6b1457736 100644 > --- a/drivers/iommu/iommu-uclass.c > +++ b/drivers/iommu/iommu-uclass.c > @@ -7,6 +7,9 @@ > > #include <common.h> > #include <dm.h> > +#include <iommu.h> > +#include <phys2bus.h> > +#include <asm/io.h> > > #if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) > int dev_iommu_enable(struct udevice *dev) > @@ -33,12 +36,37 @@ int dev_iommu_enable(struct udevice *dev) > __func__, ret); > return ret; > } > + dev->iommu = dev_iommu; > } > > return 0; > } > #endif > > +dma_addr_t dev_iommu_dma_map(struct udevice *dev, void *addr, size_t size) > +{ > + const struct iommu_ops *ops; > + > + if (dev->iommu) { > + ops = device_get_ops(dev->iommu); > + if (ops && ops->map) > + return ops->map(dev->iommu, addr, size); > + } > + > + return dev_phys_to_bus(dev, virt_to_phys(addr)); > +} > + > +void dev_iommu_dma_unmap(struct udevice *dev, dma_addr_t addr, size_t size) > +{ > + const struct iommu_ops *ops; > + > + if (dev->iommu) { > + ops = device_get_ops(dev->iommu); > + if (ops && ops->unmap) > + ops->unmap(dev->iommu, addr, size); > + } > +} > + > UCLASS_DRIVER(iommu) = { > .id = UCLASS_IOMMU, > .name = "iommu", > diff --git a/include/dm/device.h b/include/dm/device.h > index f3f953c9af..abe1927ecd 100644 > --- a/include/dm/device.h > +++ b/include/dm/device.h > @@ -194,6 +194,9 @@ struct udevice { > #if CONFIG_IS_ENABLED(DM_DMA) > ulong dma_offset; > #endif > +#if CONFIG_IS_ENABLED(IOMMU) > + struct udevice *iommu; > +#endif > }; > > static inline int dm_udevice_size(void) > diff --git a/include/iommu.h b/include/iommu.h > index 6c46adf449..cf9719c5e9 100644 > --- a/include/iommu.h > +++ b/include/iommu.h > @@ -3,6 +3,27 @@ > > struct udevice; > > +struct iommu_ops { > + /** > + * map() - map DMA memory > + * > + * @dev: device for which to map DMA memory > + * @addr: CPU address of the memory > + * @size: size of the memory > + * @return DMA address for the device > + */ > + dma_addr_t (*map)(struct udevice *dev, void *addr, size_t size); > + > + /** > + * unmap() - unmap DMA memory > + * > + * @dev: device for which to unmap DMA memory > + * @addr: DMA address of the memory > + * @size: size of the memory > + */ > + void (*unmap)(struct udevice *dev, dma_addr_t addr, size_t size); > +}; > + > #if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) && \ > CONFIG_IS_ENABLED(IOMMU) > int dev_iommu_enable(struct udevice *dev); > @@ -13,4 +34,7 @@ static inline int dev_iommu_enable(struct udevice *dev) > } > #endif > > +dma_addr_t dev_iommu_dma_map(struct udevice *dev, void *addr, size_t size); > +void dev_iommu_dma_unmap(struct udevice *dev, dma_addr_t addr, size_t size); > + > #endif
Please add some tests for these operations to test/dm/iommc.c Regards, Simon