[PATCH v13 net-next 15/15] net: mvpp2: add TX FC firmware check

[stefanc]

From: Stefan Chulski <stef...@marvell.com>

Patch check that TX FC firmware is running in CM3.
If not, global TX FC would be disabled.

Signed-off-by: Stefan Chulski <stef...@marvell.com>
Acked-by: Marcin Wojtas <m...@semihalf.com>
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2.h      |  1 +
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 39 ++++++++++++++++----
 2 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h 
b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
index b61a1ba..da87152 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
@@ -828,6 +828,7 @@
 
 #define MSS_THRESHOLD_STOP     768
 #define MSS_THRESHOLD_START    1024
+#define MSS_FC_MAX_TIMEOUT     5000
 
 /* RX buffer constants */
 #define MVPP2_SKB_SHINFO_SIZE \
diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c 
b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index 883d742..4ff195a 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -924,6 +924,34 @@ static void mvpp2_bm_pool_update_fc(struct mvpp2_port 
*port,
        spin_unlock_irqrestore(&port->priv->mss_spinlock, flags);
 }
 
+static int mvpp2_enable_global_fc(struct mvpp2 *priv)
+{
+       int val, timeout = 0;
+
+       /* Enable global flow control. In this stage global
+        * flow control enabled, but still disabled per port.
+        */
+       val = mvpp2_cm3_read(priv, MSS_FC_COM_REG);
+       val |= FLOW_CONTROL_ENABLE_BIT;
+       mvpp2_cm3_write(priv, MSS_FC_COM_REG, val);
+
+       /* Check if Firmware running and disable FC if not*/
+       val |= FLOW_CONTROL_UPDATE_COMMAND_BIT;
+       mvpp2_cm3_write(priv, MSS_FC_COM_REG, val);
+
+       while (timeout < MSS_FC_MAX_TIMEOUT) {
+               val = mvpp2_cm3_read(priv, MSS_FC_COM_REG);
+
+               if (!(val & FLOW_CONTROL_UPDATE_COMMAND_BIT))
+                       return 0;
+               usleep_range(10, 20);
+               timeout++;
+       }
+
+       priv->global_tx_fc = false;
+       return -EOPNOTSUPP;
+}
+
 /* Release buffer to BM */
 static inline void mvpp2_bm_pool_put(struct mvpp2_port *port, int pool,
                                     dma_addr_t buf_dma_addr,
@@ -7256,7 +7284,7 @@ static int mvpp2_probe(struct platform_device *pdev)
        struct resource *res;
        void __iomem *base;
        int i, shared;
-       int err, val;
+       int err;
 
        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
@@ -7480,13 +7508,10 @@ static int mvpp2_probe(struct platform_device *pdev)
                goto err_port_probe;
        }
 
-       /* Enable global flow control. In this stage global
-        * flow control enabled, but still disabled per port.
-        */
        if (priv->global_tx_fc && priv->hw_version != MVPP21) {
-               val = mvpp2_cm3_read(priv, MSS_FC_COM_REG);
-               val |= FLOW_CONTROL_ENABLE_BIT;
-               mvpp2_cm3_write(priv, MSS_FC_COM_REG, val);
+               err = mvpp2_enable_global_fc(priv);
+               if (err)
+                       dev_warn(&pdev->dev, "Minimum of CM3 firmware 18.09 and 
chip revision B0 required for flow control\n");
        }
 
        mvpp2_dbgfs_init(priv, pdev->name);
-- 
1.9.1