platform_devices are registered as IOMMU'able dynamically via add_device() and remove_device().
Tegra SMMU can have multiple address spaces(AS). IOMMU'able devices can belong to one of them. Multiple IOVA maps are created at boot-up, which can be attached to devices later. We reserve 2 of them for static assignment, AS[0] for system default, AS[1] for AHB clusters as protected domain from others, where there are many traditional pheripheral devices like USB, SD/MMC. They should be isolated from some smart devices like host1x for system robustness. Even if smart devices behaves wrongly, the traditional devices(SD/MMC, USB) wouldn't be affected, and the system could continue most likely. DMA API(ARM) needs ARM_DMA_USE_IOMMU to be enabled. Signed-off-by: Hiroshi Doyu <[email protected]> --- Update: Combined the following from v3. This makes more sense what they do. [PATCHv3 06/19] iommu/tegra: smmu: Select ARM_DMA_USE_IOMMU in Kconfig [PATCHv3 07/19] iommu/tegra: smmu: Create default IOVA maps [PATCHv3 08/19] iommu/tegra: smmu: Register platform_device to IOMMU dynamically [PATCHv3 19/19] iommu/tegra: smmu: Support Multiple ASID --- drivers/iommu/Kconfig | 1 + drivers/iommu/tegra-smmu.c | 68 +++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 68 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index c880eba..d1bc65d 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -170,6 +170,7 @@ config TEGRA_IOMMU_SMMU bool "Tegra SMMU IOMMU Support" depends on ARCH_TEGRA && TEGRA_AHB select IOMMU_API + select ARM_DMA_USE_IOMMU help Enables support for remapping discontiguous physical memory shared with the operating system into contiguous I/O virtual diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c index 37dd862..6968c11 100644 --- a/drivers/iommu/tegra-smmu.c +++ b/drivers/iommu/tegra-smmu.c @@ -39,6 +39,7 @@ #include <asm/page.h> #include <asm/cacheflush.h> +#include <asm/dma-iommu.h> enum smmu_hwgrp { HWGRP_AFI, @@ -319,6 +320,8 @@ struct smmu_device { struct device_node *ahb; + struct dma_iommu_mapping **map; + int num_as; struct smmu_as as[0]; /* Run-time allocated array */ }; @@ -947,6 +950,47 @@ static void smmu_iommu_domain_destroy(struct iommu_domain *domain) dev_dbg(smmu->dev, "smmu_as@%p\n", as); } +/* + * ASID[0] for the system default + * ASID[1] for PPCS("AHB bus children"), which has SDMMC + * ASID[2][3].. open for drivers, first come, first served. + */ +enum { + SYSTEM_DEFAULT, + SYSTEM_PROTECTED, +}; + +static int smmu_iommu_add_device(struct device *dev) +{ + int err = -EPROBE_DEFER; + u64 swgroups; + struct dma_iommu_mapping *map = NULL; + + swgroups = smmu_of_get_memory_client(dev); + switch (swgroups) { + case TEGRA_SWGROUP_BIT(PPCS): + map = smmu_handle->map[SYSTEM_PROTECTED]; + break; + default: + map = smmu_handle->map[SYSTEM_DEFAULT]; + break; + } + + if (map) + err = arm_iommu_attach_device(dev, map); + + pr_debug("swgroups=%016llx map=%p err=%d %s\n", + swgroups, map, err, dev_name(dev)); + + return err; +} + +static void smmu_iommu_remove_device(struct device *dev) +{ + dev_dbg(dev, "Detaching from map %p\n", to_dma_iommu_mapping(dev)); + arm_iommu_detach_device(dev); +} + static struct iommu_ops smmu_iommu_ops = { .domain_init = smmu_iommu_domain_init, .domain_destroy = smmu_iommu_domain_destroy, @@ -956,6 +1000,8 @@ static struct iommu_ops smmu_iommu_ops = { .unmap = smmu_iommu_unmap, .iova_to_phys = smmu_iommu_iova_to_phys, .domain_has_cap = smmu_iommu_domain_has_cap, + .add_device = smmu_iommu_add_device, + .remove_device = smmu_iommu_remove_device, .pgsize_bitmap = SMMU_IOMMU_PGSIZES, }; @@ -1144,6 +1190,23 @@ static int tegra_smmu_resume(struct device *dev) return err; } +static void tegra_smmu_create_default_map(struct smmu_device *smmu) +{ + int i; + + for (i = 0; i < smmu->num_as; i++) { + dma_addr_t base = smmu->iovmm_base; + size_t size = smmu->page_count << PAGE_SHIFT; + + smmu->map[i] = arm_iommu_create_mapping(&platform_bus_type, + base, size, 0); + if (IS_ERR(smmu->map[i])) + dev_err(smmu->dev, + "Couldn't create: asid=%d map=%p %pa-%pa\n", + i, smmu->map[i], &base, &base + size - 1); + } +} + static int tegra_smmu_probe(struct platform_device *pdev) { struct smmu_device *smmu; @@ -1160,13 +1223,15 @@ static int tegra_smmu_probe(struct platform_device *pdev) if (of_property_read_u32(dev->of_node, "nvidia,#asids", &asids)) return -ENODEV; - bytes = sizeof(*smmu) + asids * sizeof(*smmu->as); + bytes = sizeof(*smmu) + asids * (sizeof(*smmu->as) + + sizeof(struct dma_iommu_mapping *)); smmu = devm_kzalloc(dev, bytes, GFP_KERNEL); if (!smmu) { dev_err(dev, "failed to allocate smmu_device\n"); return -ENOMEM; } + smmu->map = (struct dma_iommu_mapping **)(smmu->as + asids); smmu->nregs = pdev->num_resources; smmu->regs = devm_kzalloc(dev, 2 * smmu->nregs * sizeof(*smmu->regs), GFP_KERNEL); @@ -1236,6 +1301,7 @@ static int tegra_smmu_probe(struct platform_device *pdev) smmu_debugfs_create(smmu); smmu_handle = smmu; bus_set_iommu(&platform_bus_type, &smmu_iommu_ops); + tegra_smmu_create_default_map(smmu); return 0; } -- 1.8.1.5 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
