diff mbox series

[v4,net] net: stmmac: dwmac4: extend timeout for VLAN Tag register busy bit check

Message ID 20240924205424.573913-1-shenwei.wang@nxp.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series [v4,net] net: stmmac: dwmac4: extend timeout for VLAN Tag register busy bit check | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 16 this patch: 16
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 12 of 12 maintainers
netdev/build_clang success Errors and warnings before: 16 this patch: 16
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 16 this patch: 16
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 38 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest pending net-next-2024-09-25--00-00 (tests: 0)

Commit Message

Shenwei Wang Sept. 24, 2024, 8:54 p.m. UTC
Increase the timeout for checking the busy bit of the VLAN Tag register
from 10µs to 500ms. This change is necessary to accommodate scenarios
where Energy Efficient Ethernet (EEE) is enabled.

Overnight testing revealed that when EEE is active, the busy bit can
remain set for up to approximately 300ms. The new 500ms timeout provides
a safety margin.

Fixes: ed64639bc1e0 ("net: stmmac: Add support for VLAN Rx filtering")
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com>
---
Changes in V4:
 - fixed the comments and R-b.

Changes in V3:
 - re-org the error-check flow per Serge's review.

Changes in v2:
 - replace the udelay with readl_poll_timeout per Simon's review.

---
 .../net/ethernet/stmicro/stmmac/dwmac4_core.c  | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

--
2.34.1
diff mbox series

Patch

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
index a1858f083eef..e65a65666cc1 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
@@ -14,6 +14,7 @@ 
 #include <linux/slab.h>
 #include <linux/ethtool.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include "stmmac.h"
 #include "stmmac_pcs.h"
 #include "dwmac4.h"
@@ -471,7 +472,7 @@  static int dwmac4_write_vlan_filter(struct net_device *dev,
 				    u8 index, u32 data)
 {
 	void __iomem *ioaddr = (void __iomem *)dev->base_addr;
-	int i, timeout = 10;
+	int ret;
 	u32 val;

 	if (index >= hw->num_vlan)
@@ -487,16 +488,15 @@  static int dwmac4_write_vlan_filter(struct net_device *dev,

 	writel(val, ioaddr + GMAC_VLAN_TAG);

-	for (i = 0; i < timeout; i++) {
-		val = readl(ioaddr + GMAC_VLAN_TAG);
-		if (!(val & GMAC_VLAN_TAG_CTRL_OB))
-			return 0;
-		udelay(1);
+	ret = readl_poll_timeout(ioaddr + GMAC_VLAN_TAG, val,
+				 !(val & GMAC_VLAN_TAG_CTRL_OB),
+				 1000, 500000);
+	if (ret) {
+		netdev_err(dev, "Timeout accessing MAC_VLAN_Tag_Filter\n");
+		return -EBUSY;
 	}

-	netdev_err(dev, "Timeout accessing MAC_VLAN_Tag_Filter\n");
-
-	return -EBUSY;
+	return 0;
 }

 static int dwmac4_add_hw_vlan_rx_fltr(struct net_device *dev,