RE: [EXT] Re: [PATCH v11 net-next 15/15] net: mvpp2: add TX FC firmware check

[Stefan Chulski]

> > 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(>dev, "CM3 firmware not running,
> version should be higher than 18.09 ");
> > +   dev_warn(>dev, "and chip revision B0\n");
> > +   dev_warn(>dev, "Flow control not
> supported\n");
> 
> I would much rather this was:
> 
>   dev_warn(>dev, "Minimum of CM3 firmware
> 18.09 and chip revision B0 required for flow control\n");
> 
> rather than trying to split it across several kernel messages.

I would repots v12 with this change soon.

Thanks,
Stefan.

Re: [PATCH v11 net-next 15/15] net: mvpp2: add TX FC firmware check

[Russell King - ARM Linux admin]

On Tue, Feb 09, 2021 at 10:42:31AM +0200, stef...@marvell.com wrote:
>   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(>dev, "CM3 firmware not running, version 
> should be higher than 18.09 ");
> + dev_warn(>dev, "and chip revision B0\n");
> + dev_warn(>dev, "Flow control not supported\n");

I would much rather this was:

dev_warn(>dev, "Minimum of CM3 firmware 18.09 and 
chip revision B0 required for flow control\n");

rather than trying to split it across several kernel messages.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!

[PATCH v11 net-next 15/15] net: mvpp2: add TX FC firmware check

[stefanc]

From: Stefan Chulski 

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

Signed-off-by: Stefan Chulski 
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2.h  |  1 +
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 42 
 2 files changed, 36 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_START1024
+#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 4d0a398..fed4521 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -931,6 +931,34 @@ static void mvpp2_bm_pool_update_fc(struct mvpp2_port 
*port,
spin_unlock_irqrestore(>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,
@@ -7263,7 +7291,7 @@ 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(>dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -7487,13 +7515,13 @@ 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(>dev, "CM3 firmware not running, version 
should be higher than 18.09 ");
+   dev_warn(>dev, "and chip revision B0\n");
+   dev_warn(>dev, "Flow control not supported\n");
+   }
}
 
mvpp2_dbgfs_init(priv, pdev->name);
-- 
1.9.1