[PATCH net] net: lan743x: Add set RFE read fifo threshold for PCI1x1x chips

Raju Lakkaraju
2024-03-07T09:00:31Z

The RFE (Receive Filtering Engine) read fifo threshold hardware default should
be overwritten to 3 for PCI1x1x Rev B0 devices to prevent lockup during some
stress tests using frames that include VLAN tags.
Rev C0 and later hardware already defaults to 3.

Fixes: bb4f6bffe33c ("net: lan743x: Add PCI11010 / PCI11414 device IDs")
Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com>
---
drivers/net/ethernet/microchip/lan743x_main.c | 17 +++++++++++++++++
drivers/net/ethernet/microchip/lan743x_main.h | 5 +++++
2 files changed, 22 insertions(+)

diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index 45e209a7d083..aec2d100ab87 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -3272,6 +3272,22 @@ static void lan743x_full_cleanup(struct lan743x_adapter *adapter)
lan743x_pci_cleanup(adapter);
}

+static int pci11x1x_set_rfe_rd_fifo_threshold(struct lan743x_adapter *adapter)
+{
+ u16 rev = adapter->csr.id_rev & ID_REV_CHIP_REV_MASK_;
+
+ if (rev == ID_REV_CHIP_REV_PCI11X1X_B0_) {
+ int misc_ctl;
+
+ misc_ctl = lan743x_csr_read(adapter, MISC_CTL_0);
+ misc_ctl &= ~MISC_CTL_0_RFE_READ_FIFO_MASK_;
+ misc_ctl |= (0x3 << MISC_CTL_0_RFE_READ_FIFO_SHIFT_);
+ lan743x_csr_write(adapter, MISC_CTL_0, misc_ctl);
+ }
+
+ return 0;
+}
+
static int lan743x_hardware_init(struct lan743x_adapter *adapter,
struct pci_dev *pdev)
{
@@ -3287,6 +3303,7 @@ static int lan743x_hardware_init(struct lan743x_adapter *adapter,
pci11x1x_strap_get_status(adapter);
spin_lock_init(&adapter->eth_syslock_spinlock);
mutex_init(&adapter->sgmii_rw_lock);
+ pci11x1x_set_rfe_rd_fifo_threshold(adapter);
} else {
adapter->max_tx_channels = LAN743X_MAX_TX_CHANNELS;
adapter->used_tx_channels = LAN743X_USED_TX_CHANNELS;
diff --git a/drivers/net/ethernet/microchip/lan743x_main.h b/drivers/net/ethernet/microchip/lan743x_main.h
index be79cb0ae5af..be0fe52e2ae1 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.h
+++ b/drivers/net/ethernet/microchip/lan743x_main.h
@@ -26,6 +26,7 @@
#define ID_REV_CHIP_REV_MASK_ (0x0000FFFF)
#define ID_REV_CHIP_REV_A0_ (0x00000000)
#define ID_REV_CHIP_REV_B0_ (0x00000010)
+#define ID_REV_CHIP_REV_PCI11X1X_B0_ (0x000000B0)

#define FPGA_REV (0x04)
#define FPGA_REV_GET_MINOR_(fpga_rev) (((fpga_rev) >> 8) & 0x000000FF)
@@ -311,6 +312,10 @@
#define SGMII_CTL_LINK_STATUS_SOURCE_ BIT(8)
#define SGMII_CTL_SGMII_POWER_DN_ BIT(1)

+#define MISC_CTL_0 (0x920)
+#define MISC_CTL_0_RFE_READ_FIFO_MASK_ GENMASK(6, 4)
+#define MISC_CTL_0_RFE_READ_FIFO_SHIFT_ (4)
+
/* Vendor Specific SGMII MMD details */
#define SR_VSMMD_PCS_ID1 0x0004
#define SR_VSMMD_PCS_ID2 0x0005
--
2.34.1