[PATCH] soc/qman: Change a comment for an entry check insid drain_mr_fqrni function

From: Karim Eshapa
Date: Sun Jun 25 2017 - 11:15:51 EST


Change the comment for an entry check inside function
drain_mr_fqrni() with sleep for sufficient period
of time instead of long time proccessor cycles.

Signed-off-by: Karim Eshapa <karim.eshapa@xxxxxxxxx>
---
drivers/soc/fsl/qbman/qman.c | 25 +++++++++++++------------
1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/soc/fsl/qbman/qman.c b/drivers/soc/fsl/qbman/qman.c
index 18d391e..636a7d7 100644
--- a/drivers/soc/fsl/qbman/qman.c
+++ b/drivers/soc/fsl/qbman/qman.c
@@ -1071,18 +1071,19 @@ static int drain_mr_fqrni(struct qm_portal *p)
msg = qm_mr_current(p);
if (!msg) {
/*
- * if MR was full and h/w had other FQRNI entries to produce, we
- * need to allow it time to produce those entries once the
- * existing entries are consumed. A worst-case situation
- * (fully-loaded system) means h/w sequencers may have to do 3-4
- * other things before servicing the portal's MR pump, each of
- * which (if slow) may take ~50 qman cycles (which is ~200
- * processor cycles). So rounding up and then multiplying this
- * worst-case estimate by a factor of 10, just to be
- * ultra-paranoid, goes as high as 10,000 cycles. NB, we consume
- * one entry at a time, so h/w has an opportunity to produce new
- * entries well before the ring has been fully consumed, so
- * we're being *really* paranoid here.
+ * if MR was full and h/w had other FQRNI entries to
+ * produce, we need to allow it time to produce those
+ * entries once the existing entries are consumed.
+ * A worst-case situation (fully-loaded system) means
+ * h/w sequencers may have to do 3-4 other things
+ * before servicing the portal's MR pump, each of
+ * which (if slow) may take ~50 qman cycles
+ * (which is ~200 processor cycles). So sleep with
+ * 1 ms would be very sufficient, after this period
+ * we can check if there is something produced.
+ * NB, we consume one entry at a time, so h/w has
+ * an opportunity to produce new entries well before
+ * the ring has been fully consumed.
*/
msleep(1);
msg = qm_mr_current(p);
--
2.7.4