Messages in this thread | | | Date | Fri, 24 Mar 2023 21:16:24 +0800 | Subject | Re: [PATCH v2] iommu/rockchip: Add missing set_platform_dma_ops callback | From | Baolu Lu <> |
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On 2023/3/24 19:11, Steven Price wrote: > Similar to exynos, we need a set_platform_dma_ops() callback for proper > operation on ARM 32 bit after recent changes in the IOMMU framework > (detach ops removal). But also the use of a NULL domain is confusing. > > Rework the code to have a singleton rk_identity_domain which is assigned > to domain when using an identity mapping rather than "detaching". This > makes the code easier to reason about. > > Signed-off-by: Steven Price <steven.price@arm.com> > --- > Changes since v1[1]: > > * Reworked the code to avoid a NULL domain, instead a singleton > rk_identity_domain is used instead. The 'detach' language is no > longer used. > > [1] https://lore.kernel.org/r/20230315164152.333251-1-steven.price%40arm.com > > drivers/iommu/rockchip-iommu.c | 50 ++++++++++++++++++++++++++-------- > 1 file changed, 39 insertions(+), 11 deletions(-) > > diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c > index f30db22ea5d7..437541004994 100644 > --- a/drivers/iommu/rockchip-iommu.c > +++ b/drivers/iommu/rockchip-iommu.c > @@ -124,6 +124,7 @@ struct rk_iommudata { > > static struct device *dma_dev; > static const struct rk_iommu_ops *rk_ops; > +static struct iommu_domain rk_identity_domain; > > static inline void rk_table_flush(struct rk_iommu_domain *dom, dma_addr_t dma, > unsigned int count) > @@ -980,26 +981,27 @@ static int rk_iommu_enable(struct rk_iommu *iommu) > return ret; > } > > -static void rk_iommu_detach_device(struct iommu_domain *domain, > - struct device *dev) > +static int rk_iommu_identity_attach(struct iommu_domain *identity_domain, > + struct device *dev) > { > struct rk_iommu *iommu; > - struct rk_iommu_domain *rk_domain = to_rk_domain(domain); > + struct rk_iommu_domain *rk_domain; > unsigned long flags; > int ret; > > /* Allow 'virtual devices' (eg drm) to detach from domain */ > iommu = rk_iommu_from_dev(dev); > if (!iommu) > - return; > + return -ENODEV; > + > + rk_domain = to_rk_domain(iommu->domain); > > dev_dbg(dev, "Detaching from iommu domain\n"); > > - /* iommu already detached */ > - if (iommu->domain != domain) > - return; > + if (iommu->domain == identity_domain) > + return 0; > > - iommu->domain = NULL; > + iommu->domain = identity_domain;
Where did identity_domain come from? Is it rk_identity_domain?
Best regards, baolu
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