From: Sasha Neftin <sasha.nef...@intel.com>
This change adds flow control settings. This is required to
enable the legacy flow control support.
Signed-off-by: Sasha Neftin <sasha.nef...@intel.com>
Tested-by: Aaron Brown <aaron.f.br...@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirs...@intel.com>
---
drivers/net/ethernet/intel/igc/igc_defines.h | 3 +++
drivers/net/ethernet/intel/igc/igc_main.c | 21 ++++++++++++++++++++
2 files changed, 24 insertions(+)
diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h
b/drivers/net/ethernet/intel/igc/igc_defines.h
index 5f6bc67cb33b..fc0ccfe38a20 100644
--- a/drivers/net/ethernet/intel/igc/igc_defines.h
+++ b/drivers/net/ethernet/intel/igc/igc_defines.h
@@ -66,6 +66,9 @@
#define IGC_CONNSW_AUTOSENSE_EN 0x1
+/* As per the EAS the maximum supported size is 9.5KB (9728 bytes) */
+#define MAX_JUMBO_FRAME_SIZE 0x2600
+
/* PBA constants */
#define IGC_PBA_34K 0x0022
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c
b/drivers/net/ethernet/intel/igc/igc_main.c
index 28072b9aa932..93f3b4e6185b 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -72,6 +72,27 @@ void igc_reset(struct igc_adapter *adapter)
{
struct pci_dev *pdev = adapter->pdev;
struct igc_hw *hw = &adapter->hw;
+ struct igc_fc_info *fc = &hw->fc;
+ u32 pba, hwm;
+
+ /* Repartition PBA for greater than 9k MTU if required */
+ pba = IGC_PBA_34K;
+
+ /* flow control settings
+ * The high water mark must be low enough to fit one full frame
+ * after transmitting the pause frame. As such we must have enough
+ * space to allow for us to complete our current transmit and then
+ * receive the frame that is in progress from the link partner.
+ * Set it to:
+ * - the full Rx FIFO size minus one full Tx plus one full Rx frame
+ */
+ hwm = (pba << 10) - (adapter->max_frame_size + MAX_JUMBO_FRAME_SIZE);
+
+ fc->high_water = hwm & 0xFFFFFFF0; /* 16-byte granularity */
+ fc->low_water = fc->high_water - 16;
+ fc->pause_time = 0xFFFF;
+ fc->send_xon = 1;
+ fc->current_mode = fc->requested_mode;
hw->mac.ops.reset_hw(hw);
--
2.21.0
