[PATCH 1/3] iommu/amd: Add logic to decode AMD IOMMU event flag

From: suravee.suthikulpanit
Date: Wed Mar 27 2013 - 19:51:34 EST


From: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>

Add logic to decode AMD IOMMU event flag based on information from AMD IOMMU specification.
This should simplify debugging IOMMU errors. Also, dump DTE information in additional cases.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
drivers/iommu/amd_iommu.c | 161 +++++++++++++++++++++++++++++++++++++--------
1 file changed, 134 insertions(+), 27 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 98f555d..477cfbb 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -592,7 +592,6 @@ static void amd_iommu_stats_init(void)
amd_iommu_stats_add(&invalidate_iotlb_all);
amd_iommu_stats_add(&pri_requests);
}
-
#endif

/****************************************************************************
@@ -601,6 +600,99 @@ static void amd_iommu_stats_init(void)
*
****************************************************************************/

+struct _event_log_flags {
+ u32 gn:1, /* 16 */
+ nx:1, /* 17 */
+ us:1, /* 18 */
+ i:1, /* 19 */
+ pr:1, /* 20 */
+ rw:1, /* 21 */
+ pe:1, /* 22 */
+ rz:1, /* 23 */
+ tr:1, /* 24 */
+ type:3, /* [27:25] */
+ _reserved_:20; /* Reserved */
+};
+
+static const char * const _invalid_transaction_desc[] = {
+ /* 000 */"Read request or non-posted write in the interrupt "
+ "addres range",
+ /* 001 */"Pretranslated transaction received from an I/O device "
+ "that has I=0 or V=0 in DTE",
+ /* 010 */"Port I/O space transaction received from an I/O device "
+ "that has IoCtl=00b in DTE",
+ /* 011 */"Posted write to invalid address range",
+ /* 100 */"Invalid read request or non-posted write",
+ /* 101 */"Posted write to the interrupt/EOI range from an I/O "
+ "device that has IntCtl=00b in DTE",
+ /* 110 */"Posted write to a reserved interrupt address range",
+ /* 111 */"Invalid transaction to the system management address range",
+};
+
+static const char * const _invalid_translation_desc[] = {
+ /* 000 */"Translation request received from an I/O device that has "
+ "I=0, or has V=0, or has V=1 and TV=0 in DTE",
+ /* 001 */"Translation request in invalid address range",
+ /* 010 */"Invalid translation request",
+ /* 011 */"Reserved",
+ /* 100 */"Reserved",
+ /* 101 */"Reserved",
+ /* 110 */"Reserved",
+ /* 111 */"Reserved",
+};
+
+static void dump_flags(int flags, int ev_type)
+{
+ struct _event_log_flags *p = (struct _event_log_flags *) &flags;
+ u32 err_type = p->type;
+
+ pr_err("AMD-Vi: Flags details:\n");
+ pr_err("AMD-Vi: Guest / Nested : %u\n", p->gn);
+ pr_err("AMD-Vi: No Execute : %u\n", p->nx);
+ pr_err("AMD-Vi: User-Supervisor : %u\n", p->us);
+ pr_err("AMD-Vi: Interrupt : %u\n", p->i);
+ pr_err("AMD-Vi: Present : %u\n", p->pr);
+ pr_err("AMD-Vi: Read / Write : %u\n", p->rw);
+ pr_err("AMD-Vi: Permission : %u\n", p->pe);
+ pr_err("AMD-Vi: Reserv bit not zero / Illegal level encoding : %u\n",
+ p->rz);
+ pr_err("AMD-Vi: Translation / Transaction : %u\n",
+ p->tr);
+ pr_err("AMD-Vi: Type of error : (0x%x) ", err_type);
+
+ if ((ev_type == EVENT_TYPE_DEV_TAB_ERR) ||
+ (ev_type == EVENT_TYPE_PAGE_TAB_ERR) ||
+ (ev_type == EVENT_TYPE_CMD_HARD_ERR)) {
+ /* Only supports up to 2 bits */
+ err_type &= 0x3;
+ switch (err_type) {
+ case 0:
+ pr_err("Reserved\n");
+ break;
+ case 1:
+ pr_err("Master Abort\n");
+ break;
+ case 2:
+ pr_err("Target Abort\n");
+ break;
+ case 3:
+ pr_err("Data Error\n");
+ break;
+ }
+ } else if (ev_type == EVENT_TYPE_INV_DEV_REQ) {
+ if (p->tr == 0) {
+ if (err_type < ARRAY_SIZE(_invalid_translation_desc))
+ printk("%s\n",
+ _invalid_translation_desc[err_type]);
+ } else {
+ if (err_type < ARRAY_SIZE(_invalid_transaction_desc))
+ printk("%s\n",
+ _invalid_transaction_desc[err_type]);
+ }
+ }
+ pr_err("AMD-Vi: (Note: Please refer to AMD IOMMU specification for details.)\n");
+}
+
static void dump_dte_entry(u16 devid)
{
int i;
@@ -619,31 +711,10 @@ static void dump_command(unsigned long phys_addr)
pr_err("AMD-Vi: CMD[%d]: %08x\n", i, cmd->data[i]);
}

-static void iommu_print_event(struct amd_iommu *iommu, void *__evt)
+static void iommu_print_event(int type, int devid, int domid,
+ int flags, u64 address)
{
- int type, devid, domid, flags;
- volatile u32 *event = __evt;
- int count = 0;
- u64 address;
-
-retry:
- type = (event[1] >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
- devid = (event[0] >> EVENT_DEVID_SHIFT) & EVENT_DEVID_MASK;
- domid = (event[1] >> EVENT_DOMID_SHIFT) & EVENT_DOMID_MASK;
- flags = (event[1] >> EVENT_FLAGS_SHIFT) & EVENT_FLAGS_MASK;
- address = (u64)(((u64)event[3]) << 32) | event[2];
-
- if (type == 0) {
- /* Did we hit the erratum? */
- if (++count == LOOP_TIMEOUT) {
- pr_err("AMD-Vi: No event written to event log\n");
- return;
- }
- udelay(1);
- goto retry;
- }
-
- printk(KERN_ERR "AMD-Vi: Event logged [");
+ pr_err("AMD-Vi: Event logged [");

switch (type) {
case EVENT_TYPE_ILL_DEV:
@@ -651,6 +722,7 @@ retry:
"address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
address, flags);
+ dump_flags(flags, type);
dump_dte_entry(devid);
break;
case EVENT_TYPE_IO_FAULT:
@@ -658,18 +730,22 @@ retry:
"domain=0x%04x address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
domid, address, flags);
+ dump_flags(flags, type);
+ dump_dte_entry(devid);
break;
case EVENT_TYPE_DEV_TAB_ERR:
printk("DEV_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
"address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
address, flags);
+ dump_flags(flags, type);
break;
case EVENT_TYPE_PAGE_TAB_ERR:
printk("PAGE_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
"domain=0x%04x address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
domid, address, flags);
+ dump_flags(flags, type);
break;
case EVENT_TYPE_ILL_CMD:
printk("ILLEGAL_COMMAND_ERROR address=0x%016llx]\n", address);
@@ -678,6 +754,7 @@ retry:
case EVENT_TYPE_CMD_HARD_ERR:
printk("COMMAND_HARDWARE_ERROR address=0x%016llx "
"flags=0x%04x]\n", address, flags);
+ dump_flags(flags, type);
break;
case EVENT_TYPE_IOTLB_INV_TO:
printk("IOTLB_INV_TIMEOUT device=%02x:%02x.%x "
@@ -690,11 +767,40 @@ retry:
"address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
address, flags);
+ dump_flags(flags, type);
+ dump_dte_entry(devid);
break;
default:
- printk(KERN_ERR "UNKNOWN type=0x%02x]\n", type);
+ printk("UNKNOWN type=0x%02x]\n", type);
+ }
+}
+
+static void iommu_handle_event(struct amd_iommu *iommu, void *__evt)
+{
+ int type, devid, domid, flags;
+ u32 *event = __evt;
+ int count = 0;
+ u64 address;
+
+retry:
+ type = (event[1] >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
+ devid = (event[0] >> EVENT_DEVID_SHIFT) & EVENT_DEVID_MASK;
+ domid = (event[1] >> EVENT_DOMID_SHIFT) & EVENT_DOMID_MASK;
+ flags = (event[1] >> EVENT_FLAGS_SHIFT) & EVENT_FLAGS_MASK;
+ address = (u64)(((u64)event[3]) << 32) | event[2];
+
+ if (type == 0) {
+ /* Did we hit the erratum? */
+ if (++count == LOOP_TIMEOUT) {
+ pr_err("AMD-Vi: No event written to event log\n");
+ return;
+ }
+ udelay(1);
+ goto retry;
}

+ iommu_print_event(type, devid, domid, flags, address);
+
memset(__evt, 0, 4 * sizeof(u32));
}

@@ -709,7 +815,7 @@ static void iommu_poll_events(struct amd_iommu *iommu)
tail = readl(iommu->mmio_base + MMIO_EVT_TAIL_OFFSET);

while (head != tail) {
- iommu_print_event(iommu, iommu->evt_buf + head);
+ iommu_handle_event(iommu, iommu->evt_buf + head);
head = (head + EVENT_ENTRY_SIZE) % iommu->evt_buf_size;
}

@@ -3270,6 +3376,7 @@ static int __init alloc_passthrough_domain(void)

return 0;
}
+
static int amd_iommu_domain_init(struct iommu_domain *dom)
{
struct protection_domain *domain;
--
1.7.10.4


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