[PATCH 5.9 019/252] net: ethernet: ti: cpsw: fix cpts irq after suspend

[Greg Kroah-Hartman]

From: Grygorii Strashko <grygorii.strashko@xxxxxx>

[ Upstream commit 2b5668733050fca85f0ab458c5b91732f9496a38 ]

Depending on the SoC/platform the CPSW can completely lose context after a
suspend/resume cycle, including CPSW wrapper (WR) which will cause reset of
WR_C0_MISC_EN register, so CPTS IRQ will became disabled.

Fix it by moving CPTS IRQ enabling in cpsw_ndo_open() where CPTS is
actually started.

Fixes: 84ea9c0a95d7 ("net: ethernet: ti: cpsw: enable cpts irq")
Reported-by: Tony Lindgren <tony@xxxxxxxxxxx>
Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
Tested-by: Tony Lindgren <tony@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201112111546.20343-1-grygorii.strashko@xxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/ti/cpsw.c     |   10 ++++++----
 drivers/net/ethernet/ti/cpsw_new.c |    9 ++++++---
 2 files changed, 12 insertions(+), 7 deletions(-)

--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -838,9 +838,12 @@ static int cpsw_ndo_open(struct net_devi
 		if (ret < 0)
 			goto err_cleanup;
 
-		if (cpts_register(cpsw->cpts))
-			dev_err(priv->dev, "error registering cpts device\n");
-
+		if (cpsw->cpts) {
+			if (cpts_register(cpsw->cpts))
+				dev_err(priv->dev, "error registering cpts device\n");
+			else
+				writel(0x10, &cpsw->wr_regs->misc_en);
+		}
 	}
 
 	cpsw_restore(priv);
@@ -1722,7 +1725,6 @@ static int cpsw_probe(struct platform_de
 
 	/* Enable misc CPTS evnt_pend IRQ */
 	cpts_set_irqpoll(cpsw->cpts, false);
-	writel(0x10, &cpsw->wr_regs->misc_en);
 
 skip_cpts:
 	cpsw_notice(priv, probe,
--- a/drivers/net/ethernet/ti/cpsw_new.c
+++ b/drivers/net/ethernet/ti/cpsw_new.c
@@ -873,8 +873,12 @@ static int cpsw_ndo_open(struct net_devi
 		if (ret < 0)
 			goto err_cleanup;
 
-		if (cpts_register(cpsw->cpts))
-			dev_err(priv->dev, "error registering cpts device\n");
+		if (cpsw->cpts) {
+			if (cpts_register(cpsw->cpts))
+				dev_err(priv->dev, "error registering cpts device\n");
+			else
+				writel(0x10, &cpsw->wr_regs->misc_en);
+		}
 
 		napi_enable(&cpsw->napi_rx);
 		napi_enable(&cpsw->napi_tx);
@@ -2009,7 +2013,6 @@ static int cpsw_probe(struct platform_de
 
 	/* Enable misc CPTS evnt_pend IRQ */
 	cpts_set_irqpoll(cpsw->cpts, false);
-	writel(0x10, &cpsw->wr_regs->misc_en);
 
 skip_cpts:
 	ret = cpsw_register_notifiers(cpsw);