gru: improve messages for malfunctioning GRUs

Improve error messages for malfunctioning GRUs.  Identify the type of
instruction that is failing.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 25 insertions, 3 deletions

diff --git a/drivers/misc/sgi-gru/gruhandles.c b/drivers/misc/sgi-gru/gruhandles.c
index 37e7cfc53b9c..806419a6b44c 100644
--- a/drivers/misc/sgi-gru/gruhandles.c
+++ b/drivers/misc/sgi-gru/gruhandles.c
@@ -54,6 +54,21 @@ static void start_instruction(void *h)
         gru_flush_cache(h);
 }
 
+static void report_instruction_timeout(void *h)
+{
+        unsigned long goff = GSEGPOFF((unsigned long)h);
+        char *id = "???";
+
+        if (TYPE_IS(CCH, goff))
+                id = "CCH";
+        else if (TYPE_IS(TGH, goff))
+                id = "TGH";
+        else if (TYPE_IS(TFH, goff))
+                id = "TFH";
+
+        panic(KERN_ALERT "GRU %p (%s) is malfunctioning\n", h, id);
+}
+
 static int wait_instruction_complete(void *h, enum mcs_op opc)
 {
         int status;
@@ -64,9 +79,10 @@ static int wait_instruction_complete(void *h, enum mcs_op opc)
                 status = GET_MSEG_HANDLE_STATUS(h);
                 if (status != CCHSTATUS_ACTIVE)
                         break;
-                if (GRU_OPERATION_TIMEOUT < (get_cycles() - start_time))
-                        panic("GRU %p is malfunctioning: start %ld, end %ld\n",
-                              h, start_time, (unsigned long)get_cycles());
+                if (GRU_OPERATION_TIMEOUT < (get_cycles() - start_time)) {
+                        report_instruction_timeout(h);
+                        start_time = get_cycles();
+                }
         }
         if (gru_options & OPT_STATS)
                 update_mcs_stats(opc, get_cycles() - start_time);
diff --git a/drivers/misc/sgi-gru/gruhandles.h b/drivers/misc/sgi-gru/gruhandles.h
index f44112242d00..47b762f89e0d 100644
--- a/drivers/misc/sgi-gru/gruhandles.h
+++ b/drivers/misc/sgi-gru/gruhandles.h
@@ -91,6 +91,12 @@
 /* Convert an arbitrary handle address to the beginning of the GRU segment */
 #define GRUBASE(h)              ((void *)((unsigned long)(h) & ~(GRU_SIZE - 1)))
 
+/* Test a valid handle address to determine the type */
+#define TYPE_IS(hn, h)          ((h) >= GRU_##hn##_BASE && (h) <        \
+                GRU_##hn##_BASE + GRU_NUM_##hn * GRU_HANDLE_STRIDE &&   \
+                (((h) & (GRU_HANDLE_STRIDE - 1)) == 0))
+
+
 /* General addressing macros. */
 static inline void *get_gseg_base_address(void *base, int ctxnum)
 {