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authorVladimir Oltean <vladimir.oltean@nxp.com>2023-10-04 14:17:08 +0300
committerDavid S. Miller <davem@davemloft.net>2023-10-06 10:59:52 +0100
commit139ad1143151a07be93bf741d4ea7c89e59f89ce (patch)
tree6a139f846b2f9ef21966fe5192d9eaa2be086cff
parent0ac87fe54a171d18c5fb5345e3ee8d14e1b06f4b (diff)
downloadlinux-139ad1143151a07be93bf741d4ea7c89e59f89ce.tar.gz
phy: lynx-28g: serialize concurrent phy_set_mode_ext() calls to shared registers
The protocol converter configuration registers PCC8, PCCC, PCCD (implemented by the driver), as well as others, control protocol converters from multiple lanes (each represented as a different struct phy). So, if there are simultaneous calls to phy_set_mode_ext() to lanes sharing the same PCC register (either for the "old" or for the "new" protocol), corruption of the values programmed to hardware is possible, because lynx_28g_rmw() has no locking. Add a spinlock in the struct lynx_28g_priv shared by all lanes, and take the global spinlock from the phy_ops :: set_mode() implementation. There are no other callers which modify PCC registers. Fixes: 8f73b37cf3fb ("phy: add support for the Layerscape SerDes 28G") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/phy/freescale/phy-fsl-lynx-28g.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/phy/freescale/phy-fsl-lynx-28g.c b/drivers/phy/freescale/phy-fsl-lynx-28g.c
index d5385d36735da6..e2187767ce00ce 100644
--- a/drivers/phy/freescale/phy-fsl-lynx-28g.c
+++ b/drivers/phy/freescale/phy-fsl-lynx-28g.c
@@ -127,6 +127,10 @@ struct lynx_28g_lane {
struct lynx_28g_priv {
void __iomem *base;
struct device *dev;
+ /* Serialize concurrent access to registers shared between lanes,
+ * like PCCn
+ */
+ spinlock_t pcc_lock;
struct lynx_28g_pll pll[LYNX_28G_NUM_PLL];
struct lynx_28g_lane lane[LYNX_28G_NUM_LANE];
@@ -397,6 +401,8 @@ static int lynx_28g_set_mode(struct phy *phy, enum phy_mode mode, int submode)
if (powered_up)
lynx_28g_power_off(phy);
+ spin_lock(&priv->pcc_lock);
+
switch (submode) {
case PHY_INTERFACE_MODE_SGMII:
case PHY_INTERFACE_MODE_1000BASEX:
@@ -413,6 +419,8 @@ static int lynx_28g_set_mode(struct phy *phy, enum phy_mode mode, int submode)
lane->interface = submode;
out:
+ spin_unlock(&priv->pcc_lock);
+
/* Power up the lane if necessary */
if (powered_up)
lynx_28g_power_on(phy);
@@ -596,6 +604,7 @@ static int lynx_28g_probe(struct platform_device *pdev)
dev_set_drvdata(dev, priv);
+ spin_lock_init(&priv->pcc_lock);
INIT_DELAYED_WORK(&priv->cdr_check, lynx_28g_cdr_lock_check);
queue_delayed_work(system_power_efficient_wq, &priv->cdr_check,