[PATCH v4] net: stmmac: fix FPE events losing

From: Jianheng Zhang
Date: Thu Nov 30 2023 - 22:23:34 EST

Next message: Stephen Rothwell: "linux-next: Fixes tag needs some work in the kvm-x86 tree"
Previous message: Kunwu Chan: "Re: [PATCH] platform/mellanox: Add a null pointer check in mlxbf_pmc_create_groups"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

The status bits of register MAC_FPE_CTRL_STS are clear on read. Using
32-bit read for MAC_FPE_CTRL_STS in dwmac5_fpe_configure() and
dwmac5_fpe_send_mpacket() clear the status bits. Then the stmmac interrupt
handler missing FPE event status and leads to FPE handshaking failure and
retries.
To avoid clear status bits of MAC_FPE_CTRL_STS in dwmac5_fpe_configure()
and dwmac5_fpe_send_mpacket(), add fpe_csr to stmmac_fpe_cfg structure to
cache the control bits of MAC_FPE_CTRL_STS and to avoid reading
MAC_FPE_CTRL_STS in those methods.

Fixes: 5a5586112b92 ("net: stmmac: support FPE link partner hand-shaking procedure")
Reviewed-by: Serge Semin <fancer.lancer@xxxxxxxxx>
Signed-off-by: Jianheng Zhang <Jianheng.Zhang@xxxxxxxxxxxx>
---
v1 -> v2:
Refactor patch to avoid using readb().
V2 -> v3:
Fix Signed-off-by tag name.
V3 -> v4:
Fix Signed-off-by tag email address.
---
drivers/net/ethernet/stmicro/stmmac/dwmac5.c | 45 +++++++++-------------
drivers/net/ethernet/stmicro/stmmac/dwmac5.h | 4 +-
.../net/ethernet/stmicro/stmmac/dwxgmac2_core.c | 3 +-
drivers/net/ethernet/stmicro/stmmac/hwif.h | 4 +-
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 8 +++-
drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c | 1 +
include/linux/stmmac.h | 1 +
7 files changed, 36 insertions(+), 30 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac5.c b/drivers/net/ethernet/stmicro/stmmac/dwmac5.c
index e95d35f..8fd1675 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac5.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac5.c
@@ -710,28 +710,22 @@ void dwmac5_est_irq_status(void __iomem *ioaddr, struct net_device *dev,
}
}

-void dwmac5_fpe_configure(void __iomem *ioaddr, u32 num_txq, u32 num_rxq,
+void dwmac5_fpe_configure(void __iomem *ioaddr, struct stmmac_fpe_cfg *cfg,
+ u32 num_txq, u32 num_rxq,
bool enable)
{
u32 value;

- if (!enable) {
- value = readl(ioaddr + MAC_FPE_CTRL_STS);
-
- value &= ~EFPE;
-
- writel(value, ioaddr + MAC_FPE_CTRL_STS);
- return;
+ if (enable) {
+ cfg->fpe_csr = EFPE;
+ value = readl(ioaddr + GMAC_RXQ_CTRL1);
+ value &= ~GMAC_RXQCTRL_FPRQ;
+ value |= (num_rxq - 1) << GMAC_RXQCTRL_FPRQ_SHIFT;
+ writel(value, ioaddr + GMAC_RXQ_CTRL1);
+ } else {
+ cfg->fpe_csr = 0;
}
-
- value = readl(ioaddr + GMAC_RXQ_CTRL1);
- value &= ~GMAC_RXQCTRL_FPRQ;
- value |= (num_rxq - 1) << GMAC_RXQCTRL_FPRQ_SHIFT;
- writel(value, ioaddr + GMAC_RXQ_CTRL1);
-
- value = readl(ioaddr + MAC_FPE_CTRL_STS);
- value |= EFPE;
- writel(value, ioaddr + MAC_FPE_CTRL_STS);
+ writel(cfg->fpe_csr, ioaddr + MAC_FPE_CTRL_STS);
}

int dwmac5_fpe_irq_status(void __iomem *ioaddr, struct net_device *dev)
@@ -741,6 +735,9 @@ int dwmac5_fpe_irq_status(void __iomem *ioaddr, struct net_device *dev)

status = FPE_EVENT_UNKNOWN;

+ /* Reads from the MAC_FPE_CTRL_STS register should only be performed
+ * here, since the status flags of MAC_FPE_CTRL_STS are "clear on read"
+ */
value = readl(ioaddr + MAC_FPE_CTRL_STS);

if (value & TRSP) {
@@ -766,19 +763,15 @@ int dwmac5_fpe_irq_status(void __iomem *ioaddr, struct net_device *dev)
return status;
}

-void dwmac5_fpe_send_mpacket(void __iomem *ioaddr, enum stmmac_mpacket_type type)
+void dwmac5_fpe_send_mpacket(void __iomem *ioaddr, struct stmmac_fpe_cfg *cfg,
+ enum stmmac_mpacket_type type)
{
- u32 value;
+ u32 value = cfg->fpe_csr;

- value = readl(ioaddr + MAC_FPE_CTRL_STS);
-
- if (type == MPACKET_VERIFY) {
- value &= ~SRSP;
+ if (type == MPACKET_VERIFY)
value |= SVER;
- } else {
- value &= ~SVER;
+ else if (type == MPACKET_RESPONSE)
value |= SRSP;
- }

writel(value, ioaddr + MAC_FPE_CTRL_STS);
}
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac5.h b/drivers/net/ethernet/stmicro/stmmac/dwmac5.h
index 53c138d..34e6207 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac5.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac5.h
@@ -153,9 +153,11 @@ int dwmac5_est_configure(void __iomem *ioaddr, struct stmmac_est *cfg,
unsigned int ptp_rate);
void dwmac5_est_irq_status(void __iomem *ioaddr, struct net_device *dev,
struct stmmac_extra_stats *x, u32 txqcnt);
-void dwmac5_fpe_configure(void __iomem *ioaddr, u32 num_txq, u32 num_rxq,
+void dwmac5_fpe_configure(void __iomem *ioaddr, struct stmmac_fpe_cfg *cfg,
+ u32 num_txq, u32 num_rxq,
bool enable);
void dwmac5_fpe_send_mpacket(void __iomem *ioaddr,
+ struct stmmac_fpe_cfg *cfg,
enum stmmac_mpacket_type type);
int dwmac5_fpe_irq_status(void __iomem *ioaddr, struct net_device *dev);

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
index 453e88b..a74e71d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
@@ -1484,7 +1484,8 @@ static int dwxgmac3_est_configure(void __iomem *ioaddr, struct stmmac_est *cfg,
return 0;
}

-static void dwxgmac3_fpe_configure(void __iomem *ioaddr, u32 num_txq,
+static void dwxgmac3_fpe_configure(void __iomem *ioaddr, struct stmmac_fpe_cfg *cfg,
+ u32 num_txq,
u32 num_rxq, bool enable)
{
u32 value;
diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.h b/drivers/net/ethernet/stmicro/stmmac/hwif.h
index b95d3e1..68aa2d5 100644
--- a/drivers/net/ethernet/stmicro/stmmac/hwif.h
+++ b/drivers/net/ethernet/stmicro/stmmac/hwif.h
@@ -412,9 +412,11 @@ struct stmmac_ops {
unsigned int ptp_rate);
void (*est_irq_status)(void __iomem *ioaddr, struct net_device *dev,
struct stmmac_extra_stats *x, u32 txqcnt);
- void (*fpe_configure)(void __iomem *ioaddr, u32 num_txq, u32 num_rxq,
+ void (*fpe_configure)(void __iomem *ioaddr, struct stmmac_fpe_cfg *cfg,
+ u32 num_txq, u32 num_rxq,
bool enable);
void (*fpe_send_mpacket)(void __iomem *ioaddr,
+ struct stmmac_fpe_cfg *cfg,
enum stmmac_mpacket_type type);
int (*fpe_irq_status)(void __iomem *ioaddr, struct net_device *dev);
};
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 3e50fd5..7791e9b 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -964,7 +964,8 @@ static void stmmac_fpe_link_state_handle(struct stmmac_priv *priv, bool is_up)
bool *hs_enable = &fpe_cfg->hs_enable;

if (is_up && *hs_enable) {
- stmmac_fpe_send_mpacket(priv, priv->ioaddr, MPACKET_VERIFY);
+ stmmac_fpe_send_mpacket(priv, priv->ioaddr, fpe_cfg,
+ MPACKET_VERIFY);
} else {
*lo_state = FPE_STATE_OFF;
*lp_state = FPE_STATE_OFF;
@@ -5838,6 +5839,7 @@ static void stmmac_fpe_event_status(struct stmmac_priv *priv, int status)
/* If user has requested FPE enable, quickly response */
if (*hs_enable)
stmmac_fpe_send_mpacket(priv, priv->ioaddr,
+ fpe_cfg,
MPACKET_RESPONSE);
}

@@ -7262,6 +7264,7 @@ static void stmmac_fpe_lp_task(struct work_struct *work)
if (*lo_state == FPE_STATE_ENTERING_ON &&
*lp_state == FPE_STATE_ENTERING_ON) {
stmmac_fpe_configure(priv, priv->ioaddr,
+ fpe_cfg,
priv->plat->tx_queues_to_use,
priv->plat->rx_queues_to_use,
*enable);
@@ -7280,6 +7283,7 @@ static void stmmac_fpe_lp_task(struct work_struct *work)
netdev_info(priv->dev, SEND_VERIFY_MPAKCET_FMT,
*lo_state, *lp_state);
stmmac_fpe_send_mpacket(priv, priv->ioaddr,
+ fpe_cfg,
MPACKET_VERIFY);
}
/* Sleep then retry */
@@ -7294,6 +7298,7 @@ void stmmac_fpe_handshake(struct stmmac_priv *priv, bool enable)
if (priv->plat->fpe_cfg->hs_enable != enable) {
if (enable) {
stmmac_fpe_send_mpacket(priv, priv->ioaddr,
+ priv->plat->fpe_cfg,
MPACKET_VERIFY);
} else {
priv->plat->fpe_cfg->lo_fpe_state = FPE_STATE_OFF;
@@ -7754,6 +7759,7 @@ int stmmac_suspend(struct device *dev)
if (priv->dma_cap.fpesel) {
/* Disable FPE */
stmmac_fpe_configure(priv, priv->ioaddr,
+ priv->plat->fpe_cfg,
priv->plat->tx_queues_to_use,
priv->plat->rx_queues_to_use, false);

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
index ac41ef4..6ad3e0a 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
@@ -1079,6 +1079,7 @@ static int tc_setup_taprio(struct stmmac_priv *priv,

priv->plat->fpe_cfg->enable = false;
stmmac_fpe_configure(priv, priv->ioaddr,
+ priv->plat->fpe_cfg,
priv->plat->tx_queues_to_use,
priv->plat->rx_queues_to_use,
false);
diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
index 0b4658a..dee5ad6 100644
--- a/include/linux/stmmac.h
+++ b/include/linux/stmmac.h
@@ -175,6 +175,7 @@ struct stmmac_fpe_cfg {
bool hs_enable; /* FPE handshake enable */
enum stmmac_fpe_state lp_fpe_state; /* Link Partner FPE state */
enum stmmac_fpe_state lo_fpe_state; /* Local station FPE state */
+ u32 fpe_csr; /* MAC_FPE_CTRL_STS reg cache */
};

struct stmmac_safety_feature_cfg {
--
1.8.3.1

Next message: Stephen Rothwell: "linux-next: Fixes tag needs some work in the kvm-x86 tree"
Previous message: Kunwu Chan: "Re: [PATCH] platform/mellanox: Add a null pointer check in mlxbf_pmc_create_groups"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]