From: Megha Dey megha.dey@linux.intel.com
[ Upstream commit 1da8347d8505c137fb07ff06bbcd3f2bf37409bc ]
Currently, the intel iommu debugfs directory(/sys/kernel/debug/iommu/intel) gets populated only when DMA remapping is enabled (dmar_disabled = 0) irrespective of whether interrupt remapping is enabled or not.
Instead, populate the intel iommu debugfs directory if any IOMMUs are detected.
Cc: Dan Carpenter dan.carpenter@oracle.com Fixes: ee2636b8670b1 ("iommu/vt-d: Enable base Intel IOMMU debugfs support") Signed-off-by: Megha Dey megha.dey@linux.intel.com Signed-off-by: Lu Baolu baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/intel-iommu-debugfs.c | 11 ++++++++++- drivers/iommu/intel-iommu.c | 4 +++- 2 files changed, 13 insertions(+), 2 deletions(-)
--- a/drivers/iommu/intel-iommu-debugfs.c +++ b/drivers/iommu/intel-iommu-debugfs.c @@ -281,9 +281,16 @@ static int dmar_translation_struct_show( { struct dmar_drhd_unit *drhd; struct intel_iommu *iommu; + u32 sts;
rcu_read_lock(); for_each_active_iommu(iommu, drhd) { + sts = dmar_readl(iommu->reg + DMAR_GSTS_REG); + if (!(sts & DMA_GSTS_TES)) { + seq_printf(m, "DMA Remapping is not enabled on %s\n", + iommu->name); + continue; + } root_tbl_walk(m, iommu); seq_putc(m, '\n'); } @@ -353,6 +360,7 @@ static int ir_translation_struct_show(st struct dmar_drhd_unit *drhd; struct intel_iommu *iommu; u64 irta; + u32 sts;
rcu_read_lock(); for_each_active_iommu(iommu, drhd) { @@ -362,7 +370,8 @@ static int ir_translation_struct_show(st seq_printf(m, "Remapped Interrupt supported on IOMMU: %s\n", iommu->name);
- if (iommu->ir_table) { + sts = dmar_readl(iommu->reg + DMAR_GSTS_REG); + if (iommu->ir_table && (sts & DMA_GSTS_IRES)) { irta = virt_to_phys(iommu->ir_table->base); seq_printf(m, " IR table address:%llx\n", irta); ir_tbl_remap_entry_show(m, iommu); --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -4961,6 +4961,9 @@ int __init intel_iommu_init(void)
down_write(&dmar_global_lock);
+ if (!no_iommu) + intel_iommu_debugfs_init(); + if (no_iommu || dmar_disabled) { /* * We exit the function here to ensure IOMMU's remapping and @@ -5056,7 +5059,6 @@ int __init intel_iommu_init(void) pr_info("Intel(R) Virtualization Technology for Directed I/O\n");
intel_iommu_enabled = 1; - intel_iommu_debugfs_init();
return 0;