| Message ID | 5ac3788f9f61f7698cfa9c5924d62714e230f678.1597931876.git.robin.murphy@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Convert arch/arm to use iommu-dma | expand |
Hi Robin, On 8/20/20 10:08 AM, Robin Murphy wrote: > Now that arch/arm is wired up for default domains and iommu-dma, > implement the corresponding driver-side support for DMA domains. > > Signed-off-by: Robin Murphy <robin.murphy@arm.com> > --- > drivers/iommu/omap-iommu.c | 22 +++++++++++++++++++++- > 1 file changed, 21 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c > index 71f29c0927fc..ea25c2fe0418 100644 > --- a/drivers/iommu/omap-iommu.c > +++ b/drivers/iommu/omap-iommu.c > @@ -9,6 +9,7 @@ > * Paul Mundt and Toshihiro Kobayashi > */ > > +#include <linux/dma-iommu.h> > #include <linux/dma-mapping.h> > #include <linux/err.h> > #include <linux/slab.h> > @@ -1574,13 +1575,19 @@ static struct iommu_domain *omap_iommu_domain_alloc(unsigned type) > { > struct omap_iommu_domain *omap_domain; > > - if (type != IOMMU_DOMAIN_UNMANAGED) > + if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA) > return NULL; > > omap_domain = kzalloc(sizeof(*omap_domain), GFP_KERNEL); > if (!omap_domain) > return NULL; > > + if (type == IOMMU_DOMAIN_DMA && > + iommu_get_dma_cookie(&omap_domain->domain)) { > + kfree(omap_domain); > + return NULL; > + } > + > spin_lock_init(&omap_domain->lock); > > omap_domain->domain.geometry.aperture_start = 0; > @@ -1601,6 +1608,7 @@ static void omap_iommu_domain_free(struct iommu_domain *domain) > if (omap_domain->dev) > _omap_iommu_detach_dev(omap_domain, omap_domain->dev); > > + iommu_put_dma_cookie(&omap_domain->domain); > kfree(omap_domain); > } > > @@ -1736,6 +1744,17 @@ static struct iommu_group *omap_iommu_device_group(struct device *dev) > return group; > } > > +static int omap_iommu_of_xlate(struct device *dev, > + struct of_phandle_args *args) > +{ > + /* > + * Logically, some of the housekeeping from _omap_iommu_add_device() > + * should probably move here, but the minimum we *need* is simply to > + * cooperate with of_iommu at all to let iommu-dma work. > + */ > + return 0; > +} > + I have tested this series, and it is breaking the OMAP remoteproc functionality. We definitely need some more plumbing. I am currently getting MMU faults and also the DMA allocated addresses are not coming from the device-specific CMA pools (opposite of what Sakari has reported with OMAP3 ISP). Just removing the of_xlate gets me back the expected allocations, and no MMU faults, but I don't see any valid traces. The MMU devices that the OMAP IOMMU driver deals with are not traditional bus-level IOMMU devices, but local MMU devices that are present within a remote processor sub-system or hardware accelerator (eg: OMAP3 ISP). The usage is also slightly different between remoteprocs and OMAP3 ISP. The former uses the CMA pools and iommu_map/unmap API (UNMANAGED iommu domain), as the allocated regions need to be mapped using specific device addresses adhering to the firmware linker map, while OMAP3 ISP uses it like a traditional DMA pool. regards Suman > static const struct iommu_ops omap_iommu_ops = { > .domain_alloc = omap_iommu_domain_alloc, > .domain_free = omap_iommu_domain_free, > @@ -1747,6 +1766,7 @@ static const struct iommu_ops omap_iommu_ops = { > .probe_device = omap_iommu_probe_device, > .release_device = omap_iommu_release_device, > .device_group = omap_iommu_device_group, > + .of_xlate = omap_iommu_of_xlate, > .pgsize_bitmap = OMAP_IOMMU_PGSIZES, > }; > >
diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c index 71f29c0927fc..ea25c2fe0418 100644 --- a/drivers/iommu/omap-iommu.c +++ b/drivers/iommu/omap-iommu.c @@ -9,6 +9,7 @@ * Paul Mundt and Toshihiro Kobayashi */ +#include <linux/dma-iommu.h> #include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/slab.h> @@ -1574,13 +1575,19 @@ static struct iommu_domain *omap_iommu_domain_alloc(unsigned type) { struct omap_iommu_domain *omap_domain; - if (type != IOMMU_DOMAIN_UNMANAGED) + if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA) return NULL; omap_domain = kzalloc(sizeof(*omap_domain), GFP_KERNEL); if (!omap_domain) return NULL; + if (type == IOMMU_DOMAIN_DMA && + iommu_get_dma_cookie(&omap_domain->domain)) { + kfree(omap_domain); + return NULL; + } + spin_lock_init(&omap_domain->lock); omap_domain->domain.geometry.aperture_start = 0; @@ -1601,6 +1608,7 @@ static void omap_iommu_domain_free(struct iommu_domain *domain) if (omap_domain->dev) _omap_iommu_detach_dev(omap_domain, omap_domain->dev); + iommu_put_dma_cookie(&omap_domain->domain); kfree(omap_domain); } @@ -1736,6 +1744,17 @@ static struct iommu_group *omap_iommu_device_group(struct device *dev) return group; } +static int omap_iommu_of_xlate(struct device *dev, + struct of_phandle_args *args) +{ + /* + * Logically, some of the housekeeping from _omap_iommu_add_device() + * should probably move here, but the minimum we *need* is simply to + * cooperate with of_iommu at all to let iommu-dma work. + */ + return 0; +} + static const struct iommu_ops omap_iommu_ops = { .domain_alloc = omap_iommu_domain_alloc, .domain_free = omap_iommu_domain_free, @@ -1747,6 +1766,7 @@ static const struct iommu_ops omap_iommu_ops = { .probe_device = omap_iommu_probe_device, .release_device = omap_iommu_release_device, .device_group = omap_iommu_device_group, + .of_xlate = omap_iommu_of_xlate, .pgsize_bitmap = OMAP_IOMMU_PGSIZES, };
Now that arch/arm is wired up for default domains and iommu-dma, implement the corresponding driver-side support for DMA domains. Signed-off-by: Robin Murphy <robin.murphy@arm.com> --- drivers/iommu/omap-iommu.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-)