@@ -429,6 +429,70 @@ void ksz9477_freeze_mib(struct ksz_device *dev, int port, bool freeze)
mutex_unlock(&p->mib.cnt_mutex);
}
+static int ksz9477_half_duplex_monitor(struct ksz_device *dev, int port,
+ u64 tx_late_col)
+{
+ u8 lue_ctrl;
+ u32 pmavbc;
+ u16 pqm;
+ int ret;
+
+ /* Errata DS80000754 recommends monitoring potential faults in
+ * half-duplex mode. The switch might not be able to communicate anymore
+ * in these states. If you see this message, please read the
+ * errata-sheet for more information:
+ * https://ww1.microchip.com/downloads/aemDocuments/documents
+ * /UNG/ProductDocuments/Errata/KSZ9477S-Errata-DS80000754.pdf
+ * To workaround this issue, half-duplex mode should be avoided.
+ * A software reset could be implemented to recover from this state.
+ */
+ dev_warn_once(dev->dev,
+ "Half-duplex detected on port %d, transmission halt may occur\n",
+ port);
+ if (tx_late_col != 0) {
+ /* Transmission halt with late collisions */
+ dev_crit_once(dev->dev,
+ "TX late collisions detected, transmission may be halted on port %d\n",
+ port);
+ }
+ ret = ksz_read8(dev, REG_SW_LUE_CTRL_0, &lue_ctrl);
+ if (ret)
+ return ret;
+ if (lue_ctrl & SW_VLAN_ENABLE) {
+ ret = ksz_pread16(dev, port, REG_PORT_QM_TX_CNT_0__4, &pqm);
+ if (ret)
+ return ret;
+ ret = ksz_read32(dev, REG_PMAVBC, &pmavbc);
+ if (ret)
+ return ret;
+ if ((FIELD_GET(PMAVBC_MASK, pmavbc) <= PMAVBC_MIN) ||
+ (FIELD_GET(PORT_QM_TX_CNT_M, pqm) >= PORT_QM_TX_CNT_MAX)) {
+ /* Transmission halt with Half-Duplex and VLAN */
+ dev_crit_once(dev->dev,
+ "resources out of limits, transmission may be halted\n");
+ }
+ }
+
+ return ret;
+}
+
+int ksz9477_errata_monitor(struct ksz_device *dev, int port,
+ u64 tx_late_col)
+{
+ u8 status;
+ int ret;
+
+ ret = ksz_pread8(dev, port, REG_PORT_STATUS_0, &status);
+ if (ret)
+ return ret;
+ if (!(FIELD_GET(PORT_INTF_SPEED_MASK, status)
+ == PORT_INTF_SPEED_NONE) &&
+ !(status & PORT_INTF_FULL_DUPLEX)) {
+ ret = ksz9477_half_duplex_monitor(dev, port, tx_late_col);
+ }
+ return ret;
+}
+
void ksz9477_port_init_cnt(struct ksz_device *dev, int port)
{
struct ksz_port_mib *mib = &dev->ports[port].mib;
@@ -36,6 +36,8 @@ int ksz9477_port_mirror_add(struct ksz_device *dev, int port,
bool ingress, struct netlink_ext_ack *extack);
void ksz9477_port_mirror_del(struct ksz_device *dev, int port,
struct dsa_mall_mirror_tc_entry *mirror);
+int ksz9477_errata_monitor(struct ksz_device *dev, int port,
+ u64 tx_late_col);
void ksz9477_get_caps(struct ksz_device *dev, int port,
struct phylink_config *config);
int ksz9477_fdb_dump(struct ksz_device *dev, int port,
@@ -843,8 +843,8 @@
#define REG_PORT_STATUS_0 0x0030
-#define PORT_INTF_SPEED_M 0x3
-#define PORT_INTF_SPEED_S 3
+#define PORT_INTF_SPEED_MASK GENMASK(4, 3)
+#define PORT_INTF_SPEED_NONE GENMASK(1, 0)
#define PORT_INTF_FULL_DUPLEX BIT(2)
#define PORT_TX_FLOW_CTRL BIT(1)
#define PORT_RX_FLOW_CTRL BIT(0)
@@ -1168,6 +1168,11 @@
#define PORT_RMII_CLK_SEL BIT(7)
#define PORT_MII_SEL_EDGE BIT(5)
+#define REG_PMAVBC 0x03AC
+
+#define PMAVBC_MASK GENMASK(26, 16)
+#define PMAVBC_MIN 0x580
+
/* 4 - MAC */
#define REG_PORT_MAC_CTRL_0 0x0400
@@ -1495,6 +1500,7 @@
#define PORT_QM_TX_CNT_USED_S 0
#define PORT_QM_TX_CNT_M (BIT(11) - 1)
+#define PORT_QM_TX_CNT_MAX 0x200
#define REG_PORT_QM_TX_CNT_1__4 0x0A14
@@ -1382,6 +1382,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
.tc_cbs_supported = true,
.ops = &ksz9477_dev_ops,
.phylink_mac_ops = &ksz9477_phylink_mac_ops,
+ .phy_errata_9477 = true,
.mib_names = ksz9477_mib_names,
.mib_cnt = ARRAY_SIZE(ksz9477_mib_names),
.reg_mib_cnt = MIB_COUNTER_NUM,
@@ -1416,6 +1417,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
.num_ipms = 8,
.ops = &ksz9477_dev_ops,
.phylink_mac_ops = &ksz9477_phylink_mac_ops,
+ .phy_errata_9477 = true,
.mib_names = ksz9477_mib_names,
.mib_cnt = ARRAY_SIZE(ksz9477_mib_names),
.reg_mib_cnt = MIB_COUNTER_NUM,
@@ -1450,6 +1452,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
.num_ipms = 8,
.ops = &ksz9477_dev_ops,
.phylink_mac_ops = &ksz9477_phylink_mac_ops,
+ .phy_errata_9477 = true,
.mib_names = ksz9477_mib_names,
.mib_cnt = ARRAY_SIZE(ksz9477_mib_names),
.reg_mib_cnt = MIB_COUNTER_NUM,
@@ -1540,6 +1543,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
.tc_cbs_supported = true,
.ops = &ksz9477_dev_ops,
.phylink_mac_ops = &ksz9477_phylink_mac_ops,
+ .phy_errata_9477 = true,
.mib_names = ksz9477_mib_names,
.mib_cnt = ARRAY_SIZE(ksz9477_mib_names),
.reg_mib_cnt = MIB_COUNTER_NUM,
@@ -1820,6 +1824,7 @@ void ksz_r_mib_stats64(struct ksz_device *dev, int port)
struct rtnl_link_stats64 *stats;
struct ksz_stats_raw *raw;
struct ksz_port_mib *mib;
+ int ret;
mib = &dev->ports[port].mib;
stats = &mib->stats64;
@@ -1861,6 +1866,12 @@ void ksz_r_mib_stats64(struct ksz_device *dev, int port)
pstats->rx_pause_frames = raw->rx_pause;
spin_unlock(&mib->stats64_lock);
+
+ if (dev->info->phy_errata_9477) {
+ ret = ksz9477_errata_monitor(dev, port, raw->tx_late_col);
+ if (ret)
+ dev_err(dev->dev, "Failed to monitor transmission halt\n");
+ }
}
void ksz88xx_r_mib_stats64(struct ksz_device *dev, int port)
@@ -66,6 +66,7 @@ struct ksz_chip_data {
bool tc_cbs_supported;
const struct ksz_dev_ops *ops;
const struct phylink_mac_ops *phylink_mac_ops;
+ bool phy_errata_9477;
bool ksz87xx_eee_link_erratum;
const struct ksz_mib_names *mib_names;
int mib_cnt;
The errata DS80000754 recommends monitoring potential faults in half-duplex mode for the KSZ9477 family. half-duplex is not very common so I just added a critical message when the fault conditions are detected. The switch can be expected to be unable to communicate anymore in these states and a software reset of the switch would be required which I did not implement. Fixes: b987e98e50ab ("dsa: add DSA switch driver for Microchip KSZ9477") Signed-off-by: Enguerrand de Ribaucourt <enguerrand.de-ribaucourt@savoirfairelinux.com> --- v8: - split the function in two to fit into 80 columns v7: https://lore.kernel.org/netdev/Znqbe6HDrajK0UVq@shell.armlinux.org.uk/ - use dev_crit_once instead of dev_crit_ratelimited The condition will remain true forever and the routine called every 5 seconds. There's no need to repeat the message. - add explanations in the comment above the warning to help users anticipate the consequences of the fault. v6: https://lore.kernel.org/netdev/20240614094642.122464-4-enguerrand.de-ribaucourt@savoirfairelinux.com/ - use macros for PORT_INTF_SPEED_MASK check - add VLAN condition before checking the resources v5: https://lore.kernel.org/all/20240604092304.314636-5-enguerrand.de-ribaucourt@savoirfairelinux.com/ - use macros for bitmasks - check for return values on ksz_pread* v4: https://lore.kernel.org/all/20240531142430.678198-6-enguerrand.de-ribaucourt@savoirfairelinux.com/ - rebase on net/main - add Fixes tag - reverse x-mas tree v3: https://lore.kernel.org/all/20240530102436.226189-6-enguerrand.de-ribaucourt@savoirfairelinux.com/ --- drivers/net/dsa/microchip/ksz9477.c | 64 +++++++++++++++++++++++++ drivers/net/dsa/microchip/ksz9477.h | 2 + drivers/net/dsa/microchip/ksz9477_reg.h | 10 +++- drivers/net/dsa/microchip/ksz_common.c | 11 +++++ drivers/net/dsa/microchip/ksz_common.h | 1 + 5 files changed, 86 insertions(+), 2 deletions(-)