iommu/tegra: gart: Add debugging facility (40c9b882) · Commits · 戴 / test

drivers/iommu/tegra-gart.c

+13 −0

Original line number	Diff line number	Diff line
		@@ -72,6 +72,8 @@ struct gart_domain {

		static struct gart_device gart_handle; / unique for a system */

		static bool gart_debug;

		#define GART_PTE(_pfn) \
		(GART_ENTRY_PHYS_ADDR_VALID \| ((_pfn) << PAGE_SHIFT))

		@@ -271,6 +273,7 @@ static int gart_iommu_map(struct iommu_domain *domain, unsigned long iova,
		struct gart_device *gart = gart_domain->gart;
		unsigned long flags;
		unsigned long pfn;
		unsigned long pte;

		if (!gart_iova_range_valid(gart, iova, bytes))
		return -EINVAL;
		@@ -282,6 +285,14 @@ static int gart_iommu_map(struct iommu_domain *domain, unsigned long iova,
		spin_unlock_irqrestore(&gart->pte_lock, flags);
		return -EINVAL;
		}
		if (gart_debug) {
		pte = gart_read_pte(gart, iova);
		if (pte & GART_ENTRY_PHYS_ADDR_VALID) {
		spin_unlock_irqrestore(&gart->pte_lock, flags);
		dev_err(gart->dev, "Page entry is in-use\n");
		return -EBUSY;
		}
		}
		gart_set_pte(gart, iova, GART_PTE(pfn));
		FLUSH_GART_REGS(gart);
		spin_unlock_irqrestore(&gart->pte_lock, flags);
		@@ -515,7 +526,9 @@ static void __exit tegra_gart_exit(void)

		subsys_initcall(tegra_gart_init);
		module_exit(tegra_gart_exit);
		module_param(gart_debug, bool, 0644);

		MODULE_PARM_DESC(gart_debug, "Enable GART debugging");
		MODULE_DESCRIPTION("IOMMU API for GART in Tegra20");
		MODULE_AUTHOR("Hiroshi DOYU <hdoyu@nvidia.com>");
		MODULE_ALIAS("platform:tegra-gart");