From: Magnus Damm <[email protected]> Add root device handling to the IPMMU driver by allowing certain DT compat strings to enable had_cache_leaf_nodes that in turn will support both root devices with interrupts and leaf devices that face the actual IPMMU consumer devices.
Signed-off-by: Magnus Damm <[email protected]> --- drivers/iommu/ipmmu-vmsa.c | 86 +++++++++++++++++++++++++++++++++++--------- 1 file changed, 69 insertions(+), 17 deletions(-) --- 0010/drivers/iommu/ipmmu-vmsa.c +++ work/drivers/iommu/ipmmu-vmsa.c 2015-12-15 21:13:00.440513000 +0900 @@ -33,6 +33,7 @@ struct ipmmu_features { bool use_ns_alias_offset; + bool has_cache_leaf_nodes; }; struct ipmmu_vmsa_device { @@ -48,10 +49,12 @@ struct ipmmu_vmsa_device { struct dma_iommu_mapping *mapping; #endif const struct ipmmu_features *features; + bool is_leaf; }; struct ipmmu_vmsa_domain { struct ipmmu_vmsa_device *mmu; + struct ipmmu_vmsa_device *root; struct iommu_domain io_domain; struct io_pgtable_cfg cfg; @@ -210,6 +213,36 @@ static void set_dev_data(struct device * } /* ----------------------------------------------------------------------------- + * Root device handling + */ + +static bool ipmmu_is_root(struct ipmmu_vmsa_device *mmu) +{ + if (mmu->features->has_cache_leaf_nodes) + return mmu->is_leaf ? false : true; + else + return true; /* older IPMMU hardware treated as single root */ +} + +static struct ipmmu_vmsa_device *ipmmu_find_root(struct ipmmu_vmsa_device *leaf) +{ + struct ipmmu_vmsa_device *mmu; + + if (ipmmu_is_root(leaf)) + return leaf; + + spin_lock(&ipmmu_devices_lock); + + list_for_each_entry(mmu, &ipmmu_devices, list) { + if (ipmmu_is_root(mmu)) + break; + } + + spin_unlock(&ipmmu_devices_lock); + return mmu; +} + +/* ----------------------------------------------------------------------------- * Read/Write Access */ @@ -226,13 +259,13 @@ static void ipmmu_write(struct ipmmu_vms static u32 ipmmu_ctx_read(struct ipmmu_vmsa_domain *domain, unsigned int reg) { - return ipmmu_read(domain->mmu, domain->context_id * IM_CTX_SIZE + reg); + return ipmmu_read(domain->root, domain->context_id * IM_CTX_SIZE + reg); } static void ipmmu_ctx_write(struct ipmmu_vmsa_domain *domain, unsigned int reg, u32 data) { - ipmmu_write(domain->mmu, domain->context_id * IM_CTX_SIZE + reg, data); + ipmmu_write(domain->root, domain->context_id * IM_CTX_SIZE + reg, data); } /* ----------------------------------------------------------------------------- @@ -355,7 +388,7 @@ static int ipmmu_domain_init_context(str * TODO: Add support for coherent walk through CCI with DVM and remove * cache handling. For now, delegate it to the io-pgtable code. */ - domain->cfg.iommu_dev = domain->mmu->dev; + domain->cfg.iommu_dev = domain->root->dev; domain->iop = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &domain->cfg, domain); @@ -365,14 +398,14 @@ static int ipmmu_domain_init_context(str /* * Find an unused context. */ - ret = bitmap_find_free_region(domain->mmu->ctx, IPMMU_CTX_MAX, 0); + ret = bitmap_find_free_region(domain->root->ctx, IPMMU_CTX_MAX, 0); if (ret < 0) { free_io_pgtable_ops(domain->iop); return ret; } domain->context_id = ret; - domain->mmu->domains[ret] = domain; + domain->root->domains[ret] = domain; /* TTBR0 */ ttbr = domain->cfg.arm_lpae_s1_cfg.ttbr[0]; @@ -532,7 +565,7 @@ static int ipmmu_attach_device(struct io struct device *dev) { struct ipmmu_vmsa_dev_data *dev_data = get_dev_data(dev); - struct ipmmu_vmsa_device *mmu = dev_data->mmu; + struct ipmmu_vmsa_device *root, *mmu = dev_data->mmu; struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); unsigned long flags; int ret = 0; @@ -542,11 +575,18 @@ static int ipmmu_attach_device(struct io return -ENXIO; } + root = ipmmu_find_root(dev_data->mmu); + if (!root) { + dev_err(dev, "Unable to locate root IPMMU\n"); + return -EAGAIN; + } + spin_lock_irqsave(&domain->lock, flags); if (!domain->mmu) { /* The domain hasn't been used yet, initialize it. */ domain->mmu = mmu; + domain->root = root; ret = ipmmu_domain_init_context(domain); } else if (domain->mmu != mmu) { /* @@ -824,6 +864,7 @@ static void ipmmu_device_reset(struct ip static const struct ipmmu_features ipmmu_features_default = { .use_ns_alias_offset = true, + .has_cache_leaf_nodes = false, }; static const struct of_device_id ipmmu_of_ids[] = { @@ -882,19 +923,30 @@ static int ipmmu_probe(struct platform_d mmu->base += IM_NS_ALIAS_OFFSET; irq = platform_get_irq(pdev, 0); - if (irq < 0) { - dev_err(&pdev->dev, "no IRQ found\n"); - return irq; - } - ret = devm_request_irq(&pdev->dev, irq, ipmmu_irq, 0, - dev_name(&pdev->dev), mmu); - if (ret < 0) { - dev_err(&pdev->dev, "failed to request IRQ %d\n", irq); - return ret; - } + /* + * Determine if this IPMMU instance is a leaf device by checking + * if an interrupt is availabile or not + */ + if (mmu->features->has_cache_leaf_nodes && irq < 0) + mmu->is_leaf = true; + + /* Root devices have mandatory IRQs */ + if (ipmmu_is_root(mmu)) { + if (irq < 0) { + dev_err(&pdev->dev, "no IRQ found\n"); + return irq; + } - ipmmu_device_reset(mmu); + ret = devm_request_irq(&pdev->dev, irq, ipmmu_irq, 0, + dev_name(&pdev->dev), mmu); + if (ret < 0) { + dev_err(&pdev->dev, "failed to request IRQ %d\n", irq); + return ret; + } + + ipmmu_device_reset(mmu); + } /* * We can't create the ARM mapping here as it requires the bus to have _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
