ixgbe: DCB, misallocated packet buffer size with X540 device

The X540 device has a smaller packet buffer but the DCB configuration
never took this into account. Under stress this can result in the DMA
engine hanging and TX Unit hang occurring to reset the device. This
patch reworks the packet buffer allocation routine used for DCB on
82599 and X540 devices to account for RX packet buffer sizes.

This fixes the immediate hang. We should consolidate the various
hardware specific routines for configuring features into a single
routine. This will make it much harder to miss feature cases like
this.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Tested-by: Evan Swanson <evan.swanson@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/net/ixgbe/ixgbe_x540.c b/drivers/net/ixgbe/ixgbe_x540.c
index 05f8e9cddef4..932394fce439 100644
--- a/drivers/net/ixgbe/ixgbe_x540.c
+++ b/drivers/net/ixgbe/ixgbe_x540.c
@@ -37,6 +37,7 @@
 #define IXGBE_X540_RAR_ENTRIES   128
 #define IXGBE_X540_MC_TBL_SIZE   128
 #define IXGBE_X540_VFT_TBL_SIZE  128
+#define IXGBE_X540_RX_PB_SIZE    384
 
 static s32 ixgbe_update_flash_X540(struct ixgbe_hw *hw);
 static s32 ixgbe_poll_flash_update_done_X540(struct ixgbe_hw *hw);
@@ -242,7 +243,7 @@ static s32 ixgbe_start_hw_X540(struct ixgbe_hw *hw)
                 goto out;
 
         ret_val = ixgbe_start_hw_gen2(hw);
-
+        hw->mac.rx_pb_size = IXGBE_X540_RX_PB_SIZE;
 out:
         return ret_val;
 }