firewire: ohci: log dead DMA contexts

When a DMA context goes into the dead state (and the controller thus
stops working correctly), logging this error and the controller's error
code might be helpful for debugging.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

1 files changed, 55 insertions, 4 deletions

diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index bd3c61b6dd8d..c7394361afcb 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -208,9 +208,11 @@ struct fw_ohci {
         struct context at_request_ctx;
         struct context at_response_ctx;
 
+        u32 it_context_support;
         u32 it_context_mask;     /* unoccupied IT contexts */
         struct iso_context *it_context_list;
         u64 ir_context_channels; /* unoccupied channels */
+        u32 ir_context_support;
         u32 ir_context_mask;     /* unoccupied IR contexts */
         struct iso_context *ir_context_list;
         u64 mc_channels; /* channels in use by the multichannel IR context */
@@ -338,7 +340,7 @@ static void log_irqs(u32 evt)
             !(evt & OHCI1394_busReset))
                 return;
 
-        fw_notify("IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
+        fw_notify("IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
             evt & OHCI1394_selfIDComplete       ? " selfID"             : "",
             evt & OHCI1394_RQPkt                ? " AR_req"             : "",
             evt & OHCI1394_RSPkt                ? " AR_resp"            : "",
@@ -351,6 +353,7 @@ static void log_irqs(u32 evt)
             evt & OHCI1394_cycle64Seconds       ? " cycle64Seconds"     : "",
             evt & OHCI1394_cycleInconsistent    ? " cycleInconsistent"  : "",
             evt & OHCI1394_regAccessFail        ? " regAccessFail"      : "",
+            evt & OHCI1394_unrecoverableError   ? " unrecoverableError" : "",
             evt & OHCI1394_busReset             ? " busReset"           : "",
             evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
                     OHCI1394_RSPkt | OHCI1394_reqTxComplete |
@@ -1590,6 +1593,47 @@ static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
 
 }
 
+static void detect_dead_context(struct fw_ohci *ohci,
+                                const char *name, unsigned int regs)
+{
+        u32 ctl;
+
+        ctl = reg_read(ohci, CONTROL_SET(regs));
+        if (ctl & CONTEXT_DEAD) {
+#ifdef CONFIG_FIREWIRE_OHCI_DEBUG
+                fw_error("DMA context %s has stopped, error code: %s\n",
+                         name, evts[ctl & 0x1f]);
+#else
+                fw_error("DMA context %s has stopped, error code: %#x\n",
+                         name, ctl & 0x1f);
+#endif
+        }
+}
+
+static void handle_dead_contexts(struct fw_ohci *ohci)
+{
+        unsigned int i;
+        char name[8];
+
+        detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
+        detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
+        detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
+        detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
+        for (i = 0; i < 32; ++i) {
+                if (!(ohci->it_context_support & (1 << i)))
+                        continue;
+                sprintf(name, "IT%u", i);
+                detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
+        }
+        for (i = 0; i < 32; ++i) {
+                if (!(ohci->ir_context_support & (1 << i)))
+                        continue;
+                sprintf(name, "IR%u", i);
+                detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
+        }
+        /* TODO: maybe try to flush and restart the dead contexts */
+}
+
 static u32 cycle_timer_ticks(u32 cycle_timer)
 {
         u32 ticks;
@@ -1904,6 +1948,9 @@ static irqreturn_t irq_handler(int irq, void *data)
                         fw_notify("isochronous cycle inconsistent\n");
         }
 
+        if (unlikely(event & OHCI1394_unrecoverableError))
+                handle_dead_contexts(ohci);
+
         if (event & OHCI1394_cycle64Seconds) {
                 spin_lock(&ohci->lock);
                 update_bus_time(ohci);
@@ -2141,7 +2188,9 @@ static int ohci_enable(struct fw_card *card,
                 OHCI1394_selfIDComplete |
                 OHCI1394_regAccessFail |
                 OHCI1394_cycle64Seconds |
-                OHCI1394_cycleInconsistent | OHCI1394_cycleTooLong |
+                OHCI1394_cycleInconsistent |
+                OHCI1394_unrecoverableError |
+                OHCI1394_cycleTooLong |
                 OHCI1394_masterIntEnable;
         if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
                 irqs |= OHCI1394_busReset;
@@ -3207,15 +3256,17 @@ static int __devinit pci_probe(struct pci_dev *dev,
 
         reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
         ohci->ir_context_channels = ~0ULL;
-        ohci->ir_context_mask = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
+        ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
         reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
+        ohci->ir_context_mask = ohci->ir_context_support;
         ohci->n_ir = hweight32(ohci->ir_context_mask);
         size = sizeof(struct iso_context) * ohci->n_ir;
         ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
 
         reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
-        ohci->it_context_mask = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
+        ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
         reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
+        ohci->it_context_mask = ohci->it_context_support;
         ohci->n_it = hweight32(ohci->it_context_mask);
         size = sizeof(struct iso_context) * ohci->n_it;
         ohci->it_context_list = kzalloc(size, GFP_KERNEL);