Debugfs extension for Intel IOMMU to dump Interrupt remapping table
entries for Interrupt remapping and Interrupt posting.
The file /sys/kernel/debug/intel_iommu/intel_iommu_interrupt_remap
provides detailed information, such as Index, Source Id, Destination Id,
Vector and the raw values for entries with the present bit set, in the
format shown.
Remapped Interrupt supported on IOMMU: dmar5
IR table address:93e09d54c310
---
Index SID Dest_ID Vct Raw_value_high Raw_value_low
1 3a00 0600 2c 00043a00 062c0009
1114301 0900 a2 00044301 09a20009
Posted Interrupt supported on IOMMU: dmar5
IR table address:93e09d54c310
Index SID PDA_high PDA_low Vct Raw_value_high Raw_value_low
4 4300 0010 40c7c880 41 00144300 40c7c88000418001
5 4300 0010 40c7c880 51 00144300 40c7c88000518001
Cc: Gayatri Kammela
Cc: Jacob Pan
Cc: Fenghua Yu
Cc: Ashok Raj
Signed-off-by: Sohil Mehta
---
v2: Handle the case when IR is not enabled. Fix seq_printf formatting
drivers/iommu/intel-iommu-debug.c | 123 ++
1 file changed, 123 insertions(+)
diff --git a/drivers/iommu/intel-iommu-debug.c
b/drivers/iommu/intel-iommu-debug.c
index 22a0683..7fda862 100644
--- a/drivers/iommu/intel-iommu-debug.c
+++ b/drivers/iommu/intel-iommu-debug.c
@@ -12,6 +12,7 @@
*
* Authors: Gayatri Kammela
* Jacob Pan
+ * Sohil Mehta
*
*/
@@ -280,6 +281,119 @@ static const struct file_operations intel_iommu_regs_fops
= {
.release= single_release,
};
+#ifdef CONFIG_IRQ_REMAP
+static void ir_tbl_remap_entry_show(struct seq_file *m, void *unused,
+ struct intel_iommu *iommu)
+{
+ int idx;
+ struct irte *ri_entry;
+
+ /* Print the header only once */
+ seq_printf(m, " Index SID Dest_ID Vct"
+ " Raw_value_high Raw_value_low\n");
+
+ for (idx = 0; idx < INTR_REMAP_TABLE_ENTRIES; idx++) {
+ ri_entry = &iommu->ir_table->base[idx];
+ if (!ri_entry->present || ri_entry->p_pst)
+ continue;
+ seq_printf(m,
+ " %d\t%04x %08x %02x %016llx %016llx\n",
+ idx, ri_entry->sid,
+ ri_entry->dest_id, ri_entry->vector,
+ ri_entry->high, ri_entry->low);
+ }
+}
+
+static void ir_tbl_posted_entry_show(struct seq_file *m, void *unused,
+ struct intel_iommu *iommu)
+{
+ int idx;
+ struct irte *pi_entry;
+
+ /* Print the header only once */
+ seq_printf(m, " Index SID PDA_high PDA_low Vct"
+ " Raw_value_high Raw_value_low\n");
+
+ for (idx = 0; idx < INTR_REMAP_TABLE_ENTRIES; idx++) {
+ pi_entry = &iommu->ir_table->base[idx];
+ if (!pi_entry->present || !pi_entry->p_pst)
+ continue;
+ seq_printf(m,
+ " %d\t%04x %08x %08x %02x %016llx %016llx\n",
+ idx, pi_entry->sid,
+ pi_entry->pda_h, (pi_entry->pda_l)<<6,
+ pi_entry->vector, pi_entry->high,
+ pi_entry->low);
+ }
+}
+
+/*
+ * For active IOMMUs go through the Interrupt remapping
+ * table and print valid entries in a table format for
+ * Remapped and Posted Interrupts.
+ */
+static int intel_iommu_ir_show(struct seq_file *m, void *unused)
+{
+ struct dmar_drhd_unit *drhd;
+ struct intel_iommu *iommu;
+
+ rcu_read_lock();
+ for_each_active_iommu(iommu, drhd) {
+ if (!iommu || !ecap_ir_support(iommu->ecap))
+ continue;
+
+ seq_printf(m,
+ "\nRemapped Interrupt supported on IOMMU: %s\n"
+ " IR table address:%p\n",
+ iommu->name, iommu->ir_table);
+
+ seq_printf(m, "---"
+ "\n");
+
+ if (iommu->ir_table)
+ ir_tbl_remap_entry_show(m, unused, iommu);
+ else
+ seq_printf(m, "Interrupt Remapping is not enabled\n");
+ }
+
+ seq_printf(m, "\n\t\t\t\t\t\t\t\n");
+
+ for_each_active_iommu(iommu, drhd) {
+ if (!iommu || !cap_pi_support(iommu->cap))
+ continue;
+
+ seq_printf(m,
+ "\nPosted Interrupt supported on IOMMU: %s\n"
+ " IR table address:%p\n",
+ iommu->name, iommu->ir_table);
+
+ seq_printf(m, "---