[PATCH 5.14 780/849] net: marvell: mvpp2: Fix wrong SerDes reconfiguration order

Greg Kroah-Hartman
2021-11-15T23:23:47Z

From: Marek Behún <kabel@kernel.org>

[ Upstream commit bb7bbb6e36474933540c24ae1f1ad651b843981f ]

Commit bfe301ebbc94 ("net: mvpp2: convert to use
mac_prepare()/mac_finish()") introduced a bug wherein it leaves the MAC
RESET register asserted after mac_finish(), due to wrong order of
function calls.

Before it was:
.mac_config()
mvpp22_mode_reconfigure()
assert reset
mvpp2_xlg_config()
deassert reset

Now it is:
.mac_prepare()
.mac_config()
mvpp2_xlg_config()
deassert reset
.mac_finish()
mvpp2_xlg_config()
assert reset

Obviously this is wrong.

This bug is triggered when phylink tries to change the PHY interface
mode from a GMAC mode (sgmii, 1000base-x, 2500base-x) to XLG mode
(10gbase-r, xaui). The XLG mode does not work since reset is left
asserted. Only after
ifconfig down && ifconfig up
is called will the XLG mode work.

Move the call to mvpp22_mode_reconfigure() to .mac_prepare()
implementation. Since some of the subsequent functions need to know
whether the interface is being changed, we unfortunately also need to
pass around the new interface mode before setting port->phy_interface.

Fixes: bfe301ebbc94 ("net: mvpp2: convert to use mac_prepare()/mac_finish()")
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../net/ethernet/marvell/mvpp2/mvpp2_main.c | 38 ++++++++++---------
1 file changed, 20 insertions(+), 18 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index 3229bafa2a2c7..3e673e40e878e 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -1605,7 +1605,7 @@ static void mvpp22_gop_fca_set_periodic_timer(struct mvpp2_port *port)
mvpp22_gop_fca_enable_periodic(port, true);
}

-static int mvpp22_gop_init(struct mvpp2_port *port)
+static int mvpp22_gop_init(struct mvpp2_port *port, phy_interface_t interface)
{
struct mvpp2 *priv = port->priv;
u32 val;
@@ -1613,7 +1613,7 @@ static int mvpp22_gop_init(struct mvpp2_port *port)
if (!priv->sysctrl_base)
return 0;

- switch (port->phy_interface) {
+ switch (interface) {
case PHY_INTERFACE_MODE_RGMII:
case PHY_INTERFACE_MODE_RGMII_ID:
case PHY_INTERFACE_MODE_RGMII_RXID:
@@ -1743,15 +1743,15 @@ static void mvpp22_gop_setup_irq(struct mvpp2_port *port)
* lanes by the physical layer. This is why configurations like
* "PPv2 (2500BaseX) - COMPHY (2500SGMII)" are valid.
*/
-static int mvpp22_comphy_init(struct mvpp2_port *port)
+static int mvpp22_comphy_init(struct mvpp2_port *port,
+ phy_interface_t interface)
{
int ret;

if (!port->comphy)
return 0;

- ret = phy_set_mode_ext(port->comphy, PHY_MODE_ETHERNET,
- port->phy_interface);
+ ret = phy_set_mode_ext(port->comphy, PHY_MODE_ETHERNET, interface);
if (ret)
return ret;

@@ -2172,7 +2172,8 @@ static void mvpp22_pcs_reset_assert(struct mvpp2_port *port)
writel(val & ~MVPP22_XPCS_CFG0_RESET_DIS, xpcs + MVPP22_XPCS_CFG0);
}

-static void mvpp22_pcs_reset_deassert(struct mvpp2_port *port)
+static void mvpp22_pcs_reset_deassert(struct mvpp2_port *port,
+ phy_interface_t interface)
{
struct mvpp2 *priv = port->priv;
void __iomem *mpcs, *xpcs;
@@ -2184,7 +2185,7 @@ static void mvpp22_pcs_reset_deassert(struct mvpp2_port *port)
mpcs = priv->iface_base + MVPP22_MPCS_BASE(port->gop_id);
xpcs = priv->iface_base + MVPP22_XPCS_BASE(port->gop_id);

- switch (port->phy_interface) {
+ switch (interface) {
case PHY_INTERFACE_MODE_10GBASER:
val = readl(mpcs + MVPP22_MPCS_CLK_RESET);
val |= MAC_CLK_RESET_MAC | MAC_CLK_RESET_SD_RX |
@@ -4529,7 +4530,8 @@ static int mvpp2_poll(struct napi_struct *napi, int budget)
return rx_done;
}

-static void mvpp22_mode_reconfigure(struct mvpp2_port *port)
+static void mvpp22_mode_reconfigure(struct mvpp2_port *port,
+ phy_interface_t interface)
{
u32 ctrl3;

@@ -4540,18 +4542,18 @@ static void mvpp22_mode_reconfigure(struct mvpp2_port *port)
mvpp22_pcs_reset_assert(port);

/* comphy reconfiguration */
- mvpp22_comphy_init(port);
+ mvpp22_comphy_init(port, interface);

/* gop reconfiguration */
- mvpp22_gop_init(port);
+ mvpp22_gop_init(port, interface);

- mvpp22_pcs_reset_deassert(port);
+ mvpp22_pcs_reset_deassert(port, interface);

if (mvpp2_port_supports_xlg(port)) {
ctrl3 = readl(port->base + MVPP22_XLG_CTRL3_REG);
ctrl3 &= ~MVPP22_XLG_CTRL3_MACMODESELECT_MASK;

- if (mvpp2_is_xlg(port->phy_interface))
+ if (mvpp2_is_xlg(interface))
ctrl3 |= MVPP22_XLG_CTRL3_MACMODESELECT_10G;
else
ctrl3 |= MVPP22_XLG_CTRL3_MACMODESELECT_GMAC;
@@ -4559,7 +4561,7 @@ static void mvpp22_mode_reconfigure(struct mvpp2_port *port)
writel(ctrl3, port->base + MVPP22_XLG_CTRL3_REG);
}

- if (mvpp2_port_supports_xlg(port) && mvpp2_is_xlg(port->phy_interface))
+ if (mvpp2_port_supports_xlg(port) && mvpp2_is_xlg(interface))
mvpp2_xlg_max_rx_size_set(port);
else
mvpp2_gmac_max_rx_size_set(port);
@@ -4579,7 +4581,7 @@ static void mvpp2_start_dev(struct mvpp2_port *port)
mvpp2_interrupts_enable(port);

if (port->priv->hw_version >= MVPP22)
- mvpp22_mode_reconfigure(port);
+ mvpp22_mode_reconfigure(port, port->phy_interface);

if (port->phylink) {
phylink_start(port->phylink);
@@ -6462,6 +6464,9 @@ static int mvpp2__mac_prepare(struct phylink_config *config, unsigned int mode,
mvpp22_gop_mask_irq(port);

phy_power_off(port->comphy);
+
+ /* Reconfigure the serdes lanes */
+ mvpp22_mode_reconfigure(port, interface);
}
}

@@ -6516,9 +6521,6 @@ static int mvpp2_mac_finish(struct phylink_config *config, unsigned int mode,
port->phy_interface != interface) {
port->phy_interface = interface;

- /* Reconfigure the serdes lanes */
- mvpp22_mode_reconfigure(port);
-
/* Unmask interrupts */
mvpp22_gop_unmask_irq(port);
}
@@ -6945,7 +6947,7 @@ static int mvpp2_port_probe(struct platform_device *pdev,
* driver does this, we can remove this code.
*/
if (port->comphy) {
- err = mvpp22_comphy_init(port);
+ err = mvpp22_comphy_init(port, port->phy_interface);
if (err == 0)
phy_power_off(port->comphy);
}
--
2.33.0