bnx2: Set rx buffer water marks based on MTU.

The default rx buffer water marks for XOFF/XON are for 1500 MTU.  At
larger MTUs, these water marks need to be adjusted for effective
flow control.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 21 insertions, 0 deletions

diff --git a/drivers/net/bnx2.h b/drivers/net/bnx2.h
index 617d95340160..2b9649ae6307 100644
--- a/drivers/net/bnx2.h
+++ b/drivers/net/bnx2.h
@@ -4199,7 +4199,14 @@ struct l2_fhdr {
 
 #define BNX2_RBUF_CONFIG                                0x0020000c
 #define BNX2_RBUF_CONFIG_XOFF_TRIP                       (0x3ffL<<0)
+#define BNX2_RBUF_CONFIG_XOFF_TRIP_VAL(mtu)              \
+        ((((mtu) - 1500) * 31 / 1000) + 54)
 #define BNX2_RBUF_CONFIG_XON_TRIP                        (0x3ffL<<16)
+#define BNX2_RBUF_CONFIG_XON_TRIP_VAL(mtu)               \
+        ((((mtu) - 1500) * 39 / 1000) + 66)
+#define BNX2_RBUF_CONFIG_VAL(mtu)                        \
+        (BNX2_RBUF_CONFIG_XOFF_TRIP_VAL(mtu) |           \
+        (BNX2_RBUF_CONFIG_XON_TRIP_VAL(mtu) << 16))
 
 #define BNX2_RBUF_FW_BUF_ALLOC                          0x00200010
 #define BNX2_RBUF_FW_BUF_ALLOC_VALUE                     (0x1ffL<<7)
@@ -4221,11 +4228,25 @@ struct l2_fhdr {
 
 #define BNX2_RBUF_CONFIG2                               0x0020001c
 #define BNX2_RBUF_CONFIG2_MAC_DROP_TRIP                  (0x3ffL<<0)
+#define BNX2_RBUF_CONFIG2_MAC_DROP_TRIP_VAL(mtu)         \
+        ((((mtu) - 1500) * 4 / 1000) + 5)
 #define BNX2_RBUF_CONFIG2_MAC_KEEP_TRIP                  (0x3ffL<<16)
+#define BNX2_RBUF_CONFIG2_MAC_KEEP_TRIP_VAL(mtu)         \
+        ((((mtu) - 1500) * 2 / 100) + 30)
+#define BNX2_RBUF_CONFIG2_VAL(mtu)                       \
+        (BNX2_RBUF_CONFIG2_MAC_DROP_TRIP_VAL(mtu) |      \
+        (BNX2_RBUF_CONFIG2_MAC_KEEP_TRIP_VAL(mtu) << 16))
 
 #define BNX2_RBUF_CONFIG3                               0x00200020
 #define BNX2_RBUF_CONFIG3_CU_DROP_TRIP                   (0x3ffL<<0)
+#define BNX2_RBUF_CONFIG3_CU_DROP_TRIP_VAL(mtu)          \
+        ((((mtu) - 1500) * 12 / 1000) + 18)
 #define BNX2_RBUF_CONFIG3_CU_KEEP_TRIP                   (0x3ffL<<16)
+#define BNX2_RBUF_CONFIG3_CU_KEEP_TRIP_VAL(mtu)          \
+        ((((mtu) - 1500) * 2 / 100) + 30)
+#define BNX2_RBUF_CONFIG3_VAL(mtu)                       \
+        (BNX2_RBUF_CONFIG3_CU_DROP_TRIP_VAL(mtu) |       \
+        (BNX2_RBUF_CONFIG3_CU_KEEP_TRIP_VAL(mtu) << 16))
 
 #define BNX2_RBUF_PKT_DATA                              0x00208000
 #define BNX2_RBUF_CLIST_DATA                            0x00210000