| Message ID | 20250318152049.14781-1-detlev.casanova@collabora.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | iommu/rockchip: Add flush_iotlb_all ops | expand |
On 18/03/2025 3:20 pm, Detlev Casanova wrote: > From: Jonas Karlman <jonas@kwiboo.se> > > On some Rockchip cores (like the vdpu34x video decoder), the IOMMU device > is inside the the device that uses it. > > The IOMMU device can still be driven by the iommu driver, but when an > error occurs in the main device (e.g. a decoding error that resets the > decoder), the IOMMU device will also be reseted. > In such situation, the IOMMU driver and the hardware are out of sync and > IOMMU errors will start popping up. > > To avoid that, add a flush_iotlb_all function that will let the main drivers > (e.g. rkvdec) tell the IOMMU driver to write all its cached mappings into > the IOMMU hardware when such an error occured. Eww, this is the exact opposite of what flush_iotlb_all represents, and I really don't like the idea of the public IOMMU API being abused for inter-driver communication. Please have some kind of proper reset notifier mechanism - in fact with runtime PM could you not already invoke a suspend/resume cycle via the device links? AFAICS it would also work to attach to a different domain then switch back again. Or at worst just export a public interface for the other driver to invoke rk_iommu_resume() directly. Just don't hide it in something completely inappropriate - I mean, consider if someone wants to implement IOMMU_CAP_DEFERRED_FLUSH support here in future... Thanks, Robin. > Signed-off-by: Jonas Karlman <jonas@kwiboo.se> > Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> > --- > drivers/iommu/rockchip-iommu.c | 45 ++++++++++++++++++++++++++++++---- > 1 file changed, 40 insertions(+), 5 deletions(-) > > diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c > index 323cc665c357..7086716cb8fc 100644 > --- a/drivers/iommu/rockchip-iommu.c > +++ b/drivers/iommu/rockchip-iommu.c > @@ -899,6 +899,40 @@ static size_t rk_iommu_unmap(struct iommu_domain *domain, unsigned long _iova, > return unmap_size; > } > > +static void rk_iommu_flush_iotlb_all(struct iommu_domain *domain) > +{ > + struct rk_iommu_domain *rk_domain = to_rk_domain(domain); > + struct list_head *pos; > + unsigned long flags; > + int i, ret; > + > + spin_lock_irqsave(&rk_domain->iommus_lock, flags); > + list_for_each(pos, &rk_domain->iommus) { > + struct rk_iommu *iommu = list_entry(pos, struct rk_iommu, node); > + > + ret = pm_runtime_get_if_in_use(iommu->dev); > + if (!ret || WARN_ON_ONCE(ret < 0)) > + continue; > + > + if (WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks))) > + continue; > + > + rk_iommu_enable_stall(iommu); > + for (i = 0; i < iommu->num_mmu; i++) { > + rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, > + rk_ops->mk_dtentries(rk_domain->dt_dma)); > + rk_iommu_base_command(iommu->bases[i], RK_MMU_CMD_ZAP_CACHE); > + rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, RK_MMU_IRQ_MASK); > + } > + rk_iommu_enable_paging(iommu); > + rk_iommu_disable_stall(iommu); > + > + clk_bulk_disable(iommu->num_clocks, iommu->clocks); > + pm_runtime_put(iommu->dev); > + } > + spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); > +} > + > static struct rk_iommu *rk_iommu_from_dev(struct device *dev) > { > struct rk_iommudata *data = dev_iommu_priv_get(dev); > @@ -1172,11 +1206,12 @@ static const struct iommu_ops rk_iommu_ops = { > .pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP, > .of_xlate = rk_iommu_of_xlate, > .default_domain_ops = &(const struct iommu_domain_ops) { > - .attach_dev = rk_iommu_attach_device, > - .map_pages = rk_iommu_map, > - .unmap_pages = rk_iommu_unmap, > - .iova_to_phys = rk_iommu_iova_to_phys, > - .free = rk_iommu_domain_free, > + .attach_dev = rk_iommu_attach_device, > + .map_pages = rk_iommu_map, > + .unmap_pages = rk_iommu_unmap, > + .flush_iotlb_all = rk_iommu_flush_iotlb_all, > + .iova_to_phys = rk_iommu_iova_to_phys, > + .free = rk_iommu_domain_free, > } > }; >
diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c index 323cc665c357..7086716cb8fc 100644 --- a/drivers/iommu/rockchip-iommu.c +++ b/drivers/iommu/rockchip-iommu.c @@ -899,6 +899,40 @@ static size_t rk_iommu_unmap(struct iommu_domain *domain, unsigned long _iova, return unmap_size; } +static void rk_iommu_flush_iotlb_all(struct iommu_domain *domain) +{ + struct rk_iommu_domain *rk_domain = to_rk_domain(domain); + struct list_head *pos; + unsigned long flags; + int i, ret; + + spin_lock_irqsave(&rk_domain->iommus_lock, flags); + list_for_each(pos, &rk_domain->iommus) { + struct rk_iommu *iommu = list_entry(pos, struct rk_iommu, node); + + ret = pm_runtime_get_if_in_use(iommu->dev); + if (!ret || WARN_ON_ONCE(ret < 0)) + continue; + + if (WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks))) + continue; + + rk_iommu_enable_stall(iommu); + for (i = 0; i < iommu->num_mmu; i++) { + rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, + rk_ops->mk_dtentries(rk_domain->dt_dma)); + rk_iommu_base_command(iommu->bases[i], RK_MMU_CMD_ZAP_CACHE); + rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, RK_MMU_IRQ_MASK); + } + rk_iommu_enable_paging(iommu); + rk_iommu_disable_stall(iommu); + + clk_bulk_disable(iommu->num_clocks, iommu->clocks); + pm_runtime_put(iommu->dev); + } + spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); +} + static struct rk_iommu *rk_iommu_from_dev(struct device *dev) { struct rk_iommudata *data = dev_iommu_priv_get(dev); @@ -1172,11 +1206,12 @@ static const struct iommu_ops rk_iommu_ops = { .pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP, .of_xlate = rk_iommu_of_xlate, .default_domain_ops = &(const struct iommu_domain_ops) { - .attach_dev = rk_iommu_attach_device, - .map_pages = rk_iommu_map, - .unmap_pages = rk_iommu_unmap, - .iova_to_phys = rk_iommu_iova_to_phys, - .free = rk_iommu_domain_free, + .attach_dev = rk_iommu_attach_device, + .map_pages = rk_iommu_map, + .unmap_pages = rk_iommu_unmap, + .flush_iotlb_all = rk_iommu_flush_iotlb_all, + .iova_to_phys = rk_iommu_iova_to_phys, + .free = rk_iommu_domain_free, } };