Toggle the SCU reset before hardware initialization.

Signed-off-by: Jacky Chou <jacky_chou@aspeedtech.com>
---
 drivers/net/ethernet/faraday/ftgmac100.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index 17ec35e75a65..cae23b712a6d 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -9,6 +9,7 @@
 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
 
 #include <linux/clk.h>
+#include <linux/reset.h>
 #include <linux/dma-mapping.h>
 #include <linux/etherdevice.h>
 #include <linux/ethtool.h>
@@ -98,6 +99,7 @@ struct ftgmac100 {
 	struct work_struct reset_task;
 	struct mii_bus *mii_bus;
 	struct clk *clk;
+	struct reset_control *rst;
 
 	/* AST2500/AST2600 RMII ref clock gate */
 	struct clk *rclk;
@@ -1969,10 +1971,29 @@ static int ftgmac100_probe(struct platform_device *pdev)
 	}
 
 	if (priv->is_aspeed) {
+		struct reset_control *rst;
+
 		err = ftgmac100_setup_clk(priv);
 		if (err)
 			goto err_phy_connect;
 
+		rst = devm_reset_control_get_optional(priv->dev, NULL);
+		if (IS_ERR(rst))
+			goto err_register_netdev;
+		priv->rst = rst;
+
+		err = reset_control_assert(priv->rst);
+		if (err) {
+			dev_err(priv->dev, "Failed to reset mac (%d)\n", err);
+			goto err_register_netdev;
+		}
+		usleep_range(10000, 20000);
+		err = reset_control_deassert(priv->rst);
+		if (err) {
+			dev_err(priv->dev, "Failed to deassert mac reset (%d)\n", err);
+			goto err_register_netdev;
+		}
+
 		/* Disable ast2600 problematic HW arbitration */
 		if (of_device_is_compatible(np, "aspeed,ast2600-mac"))
 			iowrite32(FTGMAC100_TM_DEFAULT,
-- 
2.25.1

On Mo, 2024-11-18 at 14:02 +0800, Jacky Chou wrote:
> Toggle the SCU reset before hardware initialization.
> 
> Signed-off-by: Jacky Chou <jacky_chou@aspeedtech.com>
> ---
>  drivers/net/ethernet/faraday/ftgmac100.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
> index 17ec35e75a65..cae23b712a6d 100644
> --- a/drivers/net/ethernet/faraday/ftgmac100.c
> +++ b/drivers/net/ethernet/faraday/ftgmac100.c
> @@ -9,6 +9,7 @@
>  #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
>  
>  #include <linux/clk.h>
> +#include <linux/reset.h>
>  #include <linux/dma-mapping.h>
>  #include <linux/etherdevice.h>
>  #include <linux/ethtool.h>
> @@ -98,6 +99,7 @@ struct ftgmac100 {
>  	struct work_struct reset_task;
>  	struct mii_bus *mii_bus;
>  	struct clk *clk;
> +	struct reset_control *rst;
>  
>  	/* AST2500/AST2600 RMII ref clock gate */
>  	struct clk *rclk;
> @@ -1969,10 +1971,29 @@ static int ftgmac100_probe(struct platform_device *pdev)
>  	}
>  
>  	if (priv->is_aspeed) {
> +		struct reset_control *rst;
> +
>  		err = ftgmac100_setup_clk(priv);
>  		if (err)
>  			goto err_phy_connect;
>  
> +		rst = devm_reset_control_get_optional(priv->dev, NULL);

Please use devm_reset_control_get_optional_exclusive() directly.


regards
Philipp

On Mon, Nov 18, 2024, at 07:02, Jacky Chou wrote:
> @@ -1969,10 +1971,29 @@ static int ftgmac100_probe(struct platform_device *pdev)
>  	}
> 
>  	if (priv->is_aspeed) {
> +		struct reset_control *rst;
> +
>  		err = ftgmac100_setup_clk(priv);
>  		if (err)
>  			goto err_phy_connect;
> 
> +		rst = devm_reset_control_get_optional(priv->dev, NULL);
> +		if (IS_ERR(rst))
> +			goto err_register_netdev;
> +		priv->rst = rst;
> +
> +		err = reset_control_assert(priv->rst);

Since that reset line is optional, how about making it
part of the normal probe procedure, not just the if(aspeed)
section? It seems this does nothing for older devices but
may help for future ones regardless of the SoC family.

      Arnd