IB/ipath: Add flag and handling for chips with swapped register bug

The 6110 had a bug that caused some registers to be swapped; it was
fixed for the 7220 (and didn't affect the 6120 because it had fewer
registers).  This adds a flag and related code to handle that, and
includes some minor cleanups in the same area.

Signed-off-by:  Ralph Campbell <ralph.campbell@qlogic.com>

5 files changed, 10 insertions, 16 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c
index f130652cfaa3..5a9dc317f40a 100644
--- a/drivers/infiniband/hw/ipath/ipath_driver.c
+++ b/drivers/infiniband/hw/ipath/ipath_driver.c
@@ -1340,14 +1340,9 @@ static void ipath_update_pio_bufs(struct ipath_devdata *dd)
                 /*
                  * Chip Errata: bug 6641; even and odd qwords>3 are swapped
                  */
-                if (i > 3) {
-                        if (i & 1)
-                                piov = le64_to_cpu(
-                                        dd->ipath_pioavailregs_dma[i - 1]);
-                        else
-                                piov = le64_to_cpu(
-                                        dd->ipath_pioavailregs_dma[i + 1]);
-                } else
+                if (i > 3 && (dd->ipath_flags & IPATH_SWAP_PIOBUFS))
+                        piov = le64_to_cpu(dd->ipath_pioavailregs_dma[i ^ 1]);
+                else
                         piov = le64_to_cpu(dd->ipath_pioavailregs_dma[i]);
                 pchg = _IPATH_ALL_CHECKBITS &
                         ~(dd->ipath_pioavailshadow[i] ^ piov);
diff --git a/drivers/infiniband/hw/ipath/ipath_iba6110.c b/drivers/infiniband/hw/ipath/ipath_iba6110.c
index 0c900c51e538..3bfaf04a2148 100644
--- a/drivers/infiniband/hw/ipath/ipath_iba6110.c
+++ b/drivers/infiniband/hw/ipath/ipath_iba6110.c
@@ -1043,6 +1043,8 @@ static int ipath_setup_ht_config(struct ipath_devdata *dd,
         } while ((pos = pci_find_next_capability(pdev, pos,
                                                  PCI_CAP_ID_HT)));
 
+        dd->ipath_flags |= IPATH_SWAP_PIOBUFS;
+
 bail:
         return ret;
 }
diff --git a/drivers/infiniband/hw/ipath/ipath_init_chip.c b/drivers/infiniband/hw/ipath/ipath_init_chip.c
index 3174c315999b..4471674975cd 100644
--- a/drivers/infiniband/hw/ipath/ipath_init_chip.c
+++ b/drivers/infiniband/hw/ipath/ipath_init_chip.c
@@ -528,12 +528,8 @@ static void enable_chip(struct ipath_devdata *dd,
                 /*
                  * Chip Errata bug 6641; even and odd qwords>3 are swapped.
                  */
-                if (i > 3) {
-                        if (i & 1)
-                                val = dd->ipath_pioavailregs_dma[i - 1];
-                        else
-                                val = dd->ipath_pioavailregs_dma[i + 1];
-                }
+                if (i > 3 && (dd->ipath_flags & IPATH_SWAP_PIOBUFS))
+                        val = dd->ipath_pioavailregs_dma[i ^ 1];
                 else
                         val = dd->ipath_pioavailregs_dma[i];
                 dd->ipath_pioavailshadow[i] = le64_to_cpu(val);
diff --git a/drivers/infiniband/hw/ipath/ipath_intr.c b/drivers/infiniband/hw/ipath/ipath_intr.c
index e2ce5314504d..ddc0a19c5eee 100644
--- a/drivers/infiniband/hw/ipath/ipath_intr.c
+++ b/drivers/infiniband/hw/ipath/ipath_intr.c
@@ -831,8 +831,8 @@ void ipath_clear_freeze(struct ipath_devdata *dd)
          */
         for (i = 0; i < dd->ipath_pioavregs; i++) {
                 /* deal with 6110 chip bug */
-                im = i > 3 ? ((i&1) ? i-1 : i+1) : i;
-                val = ipath_read_kreg64(dd, (0x1000/sizeof(u64))+im);
+                im = i > 3 ? i ^ 1 : i;
+                val = ipath_read_kreg64(dd, (0x1000 / sizeof(u64)) + im);
                 dd->ipath_pioavailregs_dma[i] = dd->ipath_pioavailshadow[i]
                         = le64_to_cpu(val);
         }
diff --git a/drivers/infiniband/hw/ipath/ipath_kernel.h b/drivers/infiniband/hw/ipath/ipath_kernel.h
index b9cca8403239..e07df0068312 100644
--- a/drivers/infiniband/hw/ipath/ipath_kernel.h
+++ b/drivers/infiniband/hw/ipath/ipath_kernel.h
@@ -756,6 +756,7 @@ int ipath_set_rx_pol_inv(struct ipath_devdata *dd, u8 new_pol_inv);
 #define IPATH_DISABLED      0x80000 /* administratively disabled */
                 /* Use GPIO interrupts for new counters */
 #define IPATH_GPIO_ERRINTRS 0x100000
+#define IPATH_SWAP_PIOBUFS  0x200000
 
 /* Bits in GPIO for the added interrupts */
 #define IPATH_GPIO_PORT0_BIT 2