The data_in_hold_time measured on the oscilloscope does not meet the
hardware requirement, which can corrupt SFP EEPROM reads over I2C.
Set the I2C SDA hold time to 100 (0x64) I2C clock periods for both
RX and TX in txgbe_i2c_start().
Fixes: 00970f6398c8 ("net/txgbe: fix reading SFP module SFF-8472 data")
Cc: [email protected]
Signed-off-by: Zaiyu Wang <[email protected]>
---
drivers/net/txgbe/base/txgbe_phy.c | 3 +++
drivers/net/txgbe/base/txgbe_regs.h | 3 +++
2 files changed, 6 insertions(+)
diff --git a/drivers/net/txgbe/base/txgbe_phy.c
b/drivers/net/txgbe/base/txgbe_phy.c
index 2fbe50e242..8b653f0aeb 100644
--- a/drivers/net/txgbe/base/txgbe_phy.c
+++ b/drivers/net/txgbe/base/txgbe_phy.c
@@ -1334,6 +1334,9 @@ static void txgbe_i2c_start(struct txgbe_hw *hw, u8
dev_addr)
wr32(hw, TXGBE_I2CSCLTMOUT, 0xFFFFFF);
wr32(hw, TXGBE_I2CSDATMOUT, 0xFFFFFF);
+ wr32m(hw, TXGBE_I2C_SDA_HOLD,
+ TXGBE_I2C_SDA_RX_HOLD | TXGBE_I2C_SDA_TX_HOLD, 0x640064);
+
wr32(hw, TXGBE_I2CICM, 0);
wr32(hw, TXGBE_I2CENA, 1);
}
diff --git a/drivers/net/txgbe/base/txgbe_regs.h
b/drivers/net/txgbe/base/txgbe_regs.h
index bf46a80862..b0042dc0d6 100644
--- a/drivers/net/txgbe/base/txgbe_regs.h
+++ b/drivers/net/txgbe/base/txgbe_regs.h
@@ -1610,6 +1610,9 @@ enum txgbe_5tuple_protocol {
#define TXGBE_I2CSTAT_MST ((1U << 5))
#define TXGBE_I2CSCLTMOUT 0x0149AC
#define TXGBE_I2CSDATMOUT 0x0149B0 /*I2C SDA Stuck at Low Timeout*/
+#define TXGBE_I2C_SDA_HOLD 0x1497C /* SDA hold time length reg */
+#define TXGBE_I2C_SDA_RX_HOLD 0xff0000 /* SDA rx hold time length
reg */
+#define TXGBE_I2C_SDA_TX_HOLD 0xffff /* SDA tx hold time length reg
*/
/* port cfg Registers */
#define TXGBE_PORTSTAT 0x014404
--
2.55.0.windows.2
