recipes-kernel/linux/5.15/0003-net-ftgmac100-Add-scu-reset-toggling.patch

From aca30aebcd4423fed73d3d94306562e3e4c3283e Mon Sep 17 00:00:00 2001
From: Dylan Hung <dylan_hung@aspeedtech.com>
Date: Wed, 7 Dec 2022 17:34:45 +0800
Subject: [PATCH 3/3] net: ftgmac100: Add scu reset toggling

Assert and deassert the reset line to ensure the hardware is in a right
state.

v2: toggle SCU reset also in ftgmac100_init_hw.

Patch Tracking Bug: b/262485041
Upstream info / review: n/a
Inappropriate [other]:
- The commit is created to debug BMC networking issue and we will push
  Aspeed to upstream this.
Justification: Same as reasons above.

Signed-off-by: Dylan Hung <dylan_hung@aspeedtech.com>
Change-Id: If153780d98be9990d6bb56d54a60ff59e053a844
---
 drivers/net/ethernet/faraday/ftgmac100.c | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index ef8c186bb2ec..615649393cad 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>
@@ -89,6 +90,7 @@ struct ftgmac100 {
 	struct device_node *phy_dn;
 	struct mii_bus *mii_bus;
 	struct clk *clk;
+	struct reset_control *reset;
 
 	/* AST2500/AST2600 RMII ref clock gate */
 	struct clk *rclk;
@@ -249,6 +251,10 @@ static void ftgmac100_init_hw(struct ftgmac100 *priv)
 {
 	u32 reg, rfifo_sz, tfifo_sz;
 
+	reset_control_assert(priv->reset);
+	mdelay(10);
+	reset_control_deassert(priv->reset);
+
 	/* Clear stale interrupts */
 	reg = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
 	iowrite32(reg, priv->base + FTGMAC100_OFFSET_ISR);
@@ -1855,6 +1861,7 @@ static void ftgmac100_ncsi_handler(struct ncsi_dev *nd)
 static int ftgmac100_setup_clk(struct ftgmac100 *priv)
 {
 	struct clk *clk;
+	struct reset_control *reset;
 	int rc;
 
 	clk = devm_clk_get(priv->dev, NULL /* MACCLK */);
@@ -1880,8 +1887,19 @@ static int ftgmac100_setup_clk(struct ftgmac100 *priv)
 	 */
 	priv->rclk = devm_clk_get_optional(priv->dev, "RCLK");
 	rc = clk_prepare_enable(priv->rclk);
-	if (!rc)
-		return 0;
+	if (rc)
+		goto cleanup_clk;
+
+	reset = devm_reset_control_get_optional(priv->dev, NULL);
+	if (IS_ERR(reset))
+		return PTR_ERR(reset);
+	priv->reset = reset;
+
+	rc = reset_control_assert(priv->reset);
+	mdelay(10);
+	rc = reset_control_deassert(priv->reset);
+
+	return 0;
 
 cleanup_clk:
 	clk_disable_unprepare(priv->clk);
-- 
2.39.0.rc1.256.g54fd8350bd-goog