IB/ipath: Fix sendctrl locking

Code review pointed out that the locking around uses of ipath_sendctrl 
and kr_sendctrl were, in several places, incorrect and/or inconsistent.

Signed-off-by: John Gregor <john.gregor@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 16 insertions, 8 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_init_chip.c b/drivers/infiniband/hw/ipath/ipath_init_chip.c
index 9e9d6fafcf0d..1c65ab907a33 100644
--- a/drivers/infiniband/hw/ipath/ipath_init_chip.c
+++ b/drivers/infiniband/hw/ipath/ipath_init_chip.c
@@ -345,7 +345,7 @@ static int init_chip_first(struct ipath_devdata *dd,
                        dd->ipath_piobcnt2k, dd->ipath_pio2kbase);
 
         spin_lock_init(&dd->ipath_tid_lock);
-
+        spin_lock_init(&dd->ipath_sendctrl_lock);
         spin_lock_init(&dd->ipath_gpio_lock);
         spin_lock_init(&dd->ipath_eep_st_lock);
         mutex_init(&dd->ipath_eep_lock);
@@ -372,9 +372,9 @@ static int init_chip_reset(struct ipath_devdata *dd,
         *pdp = dd->ipath_pd[0];
         /* ensure chip does no sends or receives while we re-initialize */
         dd->ipath_control = dd->ipath_sendctrl = dd->ipath_rcvctrl = 0U;
-        ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl, 0);
-        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, 0);
-        ipath_write_kreg(dd, dd->ipath_kregs->kr_control, 0);
+        ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl, dd->ipath_rcvctrl);
+        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, dd->ipath_sendctrl);
+        ipath_write_kreg(dd, dd->ipath_kregs->kr_control, dd->ipath_control);
 
         rtmp = ipath_read_kreg32(dd, dd->ipath_kregs->kr_portcnt);
         if (dd->ipath_portcnt != rtmp)
@@ -487,6 +487,7 @@ static void enable_chip(struct ipath_devdata *dd,
                         struct ipath_portdata *pd, int reinit)
 {
         u32 val;
+        unsigned long flags;
         int i;
 
         if (!reinit)
@@ -495,11 +496,13 @@ static void enable_chip(struct ipath_devdata *dd,
         ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl,
                          dd->ipath_rcvctrl);
 
+        spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
         /* Enable PIO send, and update of PIOavail regs to memory. */
         dd->ipath_sendctrl = INFINIPATH_S_PIOENABLE |
                 INFINIPATH_S_PIOBUFAVAILUPD;
-        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
-                         dd->ipath_sendctrl);
+        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, dd->ipath_sendctrl);
+        ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
+        spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
 
         /*
          * enable port 0 receive, and receive interrupt.  other ports
@@ -696,6 +699,7 @@ int ipath_init_chip(struct ipath_devdata *dd, int reinit)
         u64 val;
         struct ipath_portdata *pd = NULL; /* keep gcc4 happy */
         gfp_t gfp_flags = GFP_USER | __GFP_COMP;
+        unsigned long flags;
 
         ret = init_housekeeping(dd, &pd, reinit);
         if (ret)
@@ -827,8 +831,12 @@ int ipath_init_chip(struct ipath_devdata *dd, int reinit)
         ipath_write_kreg(dd, dd->ipath_kregs->kr_hwerrclear,
                          ~0ULL&~INFINIPATH_HWE_MEMBISTFAILED);
         ipath_write_kreg(dd, dd->ipath_kregs->kr_control, 0ULL);
-        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
-                         INFINIPATH_S_PIOENABLE);
+
+        spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
+        dd->ipath_sendctrl = INFINIPATH_S_PIOENABLE;
+        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, dd->ipath_sendctrl);
+        ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
+        spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
 
         /*
          * before error clears, since we expect serdes pll errors during