Patch "net: ethernet: ti: cpsw: adjust cpsw fifos depth for fullduplex flow control" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

net: ethernet: ti: cpsw: adjust cpsw fifos depth for fullduplex flow control

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
net-ethernet-ti-cpsw-adjust-cpsw-fifos-depth-for-fullduplex-flow-control.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Grygorii Strashko <[email protected]>
Date: Mon, 8 May 2017 14:21:21 -0500
Subject: net: ethernet: ti: cpsw: adjust cpsw fifos depth for fullduplex flow control

From: Grygorii Strashko <[email protected]>

[ Upstream commit 48f5bccc60675f8426a6159935e8636a1fd89f56 ]

When users set flow control using ethtool the bits are set properly in the CPGMAC_SL MACCONTROL register, but the FIFO depth in the respective Port n Maximum FIFO Blocks (Pn_MAX_BLKS) registers remains set to the minimum size reset value. When receive flow control is enabled on a port, the port's associated FIFO block allocation must be adjusted. The port RX allocation must increase to accommodate the flow control runout. The TRM recommends numbers of 5 or 6.

Hence, apply required Port FIFO configuration to Pn_MAX_BLKS.Pn_TX_MAX_BLKS=0xF and Pn_MAX_BLKS.Pn_RX_MAX_BLKS=0x5 during interface initialization.

---
 drivers/net/ethernet/ti/cpsw.c |   16 ++++++++++++++++
 1 file changed, 16 insertions(+)

@@ -280,6 +280,10 @@ struct cpsw_ss_regs {
 /* Bit definitions for the CPSW1_TS_SEQ_LTYPE register */
 #define CPSW_V1_SEQ_ID_OFS_SHIFT	16
 
+#define CPSW_MAX_BLKS_TX		15
+#define CPSW_MAX_BLKS_TX_SHIFT		4
+#define CPSW_MAX_BLKS_RX		5
+
 struct cpsw_host_regs {
 	u32	max_blks;
 	u32	blk_cnt;

@@ -1127,11 +1131,23 @@ static void cpsw_slave_open(struct cpsw_
 	switch (priv->version) {
 	case CPSW_VERSION_1:
 		slave_write(slave, TX_PRIORITY_MAPPING, CPSW1_TX_PRI_MAP);
+		/* Increase RX FIFO size to 5 for supporting fullduplex
+		 * flow control mode
+		 */
+		slave_write(slave,
+			    (CPSW_MAX_BLKS_TX << CPSW_MAX_BLKS_TX_SHIFT) |
+			    CPSW_MAX_BLKS_RX, CPSW1_MAX_BLKS);
 		break;
 	case CPSW_VERSION_2:
 	case CPSW_VERSION_3:
 	case CPSW_VERSION_4:
 		slave_write(slave, TX_PRIORITY_MAPPING, CPSW2_TX_PRI_MAP);
+		/* Increase RX FIFO size to 5 for supporting fullduplex
+		 * flow control mode
+		 */
+		slave_write(slave,
+			    (CPSW_MAX_BLKS_TX << CPSW_MAX_BLKS_TX_SHIFT) |
+			    CPSW_MAX_BLKS_RX, CPSW2_MAX_BLKS);
 		break;
 	}
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/net-ethernet-ti-cpsw-adjust-cpsw-fifos-depth-for-fullduplex-flow-control.patch