From d9b24135b972ccdd5f5174fba06c730e895e6daf Mon Sep 17 00:00:00 2001 From: Bruce Allan Date: Fri, 13 May 2011 07:19:42 +0000 Subject: [PATCH] e1000e: disable far-end loopback mode on ESB2 The ESB2 LAN includes a debug feature that enables far-end loopback (FELB) of the SerDes/Kumeran interface. This feature is activated when receiving a sequence of symbols that includes a reserved codeword. On a perfect link, FELB would never be activated. In the presence of bit errors, there is a very small, but non-zero, probability of FELB being activated. If the FELB is activated, the SerDes link becomes non-functional and must be reset. It could also corrupt the switching tables in the switch since the ESB2 is transmitting packets with a different source MAC address. This patch disables the FELB feature. Signed-off-by: Bruce Allan Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher --- drivers/net/e1000e/es2lan.c | 8 ++++++++ drivers/net/e1000e/hw.h | 1 + 2 files changed, 9 insertions(+) diff --git a/drivers/net/e1000e/es2lan.c b/drivers/net/e1000e/es2lan.c index f4bbeb22f51..c0ecb2d9fdb 100644 --- a/drivers/net/e1000e/es2lan.c +++ b/drivers/net/e1000e/es2lan.c @@ -836,6 +836,7 @@ static s32 e1000_init_hw_80003es2lan(struct e1000_hw *hw) struct e1000_mac_info *mac = &hw->mac; u32 reg_data; s32 ret_val; + u16 kum_reg_data; u16 i; e1000_initialize_hw_bits_80003es2lan(hw); @@ -861,6 +862,13 @@ static s32 e1000_init_hw_80003es2lan(struct e1000_hw *hw) /* Setup link and flow control */ ret_val = e1000e_setup_link(hw); + /* Disable IBIST slave mode (far-end loopback) */ + e1000_read_kmrn_reg_80003es2lan(hw, E1000_KMRNCTRLSTA_INBAND_PARAM, + &kum_reg_data); + kum_reg_data |= E1000_KMRNCTRLSTA_IBIST_DISABLE; + e1000_write_kmrn_reg_80003es2lan(hw, E1000_KMRNCTRLSTA_INBAND_PARAM, + kum_reg_data); + /* Set the transmit descriptor write-back policy */ reg_data = er32(TXDCTL(0)); reg_data = (reg_data & ~E1000_TXDCTL_WTHRESH) | diff --git a/drivers/net/e1000e/hw.h b/drivers/net/e1000e/hw.h index 6c2fa8327f5..dde584f5ccc 100644 --- a/drivers/net/e1000e/hw.h +++ b/drivers/net/e1000e/hw.h @@ -312,6 +312,7 @@ enum e1e_registers { #define E1000_KMRNCTRLSTA_DIAG_OFFSET 0x3 /* Kumeran Diagnostic */ #define E1000_KMRNCTRLSTA_TIMEOUTS 0x4 /* Kumeran Timeouts */ #define E1000_KMRNCTRLSTA_INBAND_PARAM 0x9 /* Kumeran InBand Parameters */ +#define E1000_KMRNCTRLSTA_IBIST_DISABLE 0x0200 /* Kumeran IBIST Disable */ #define E1000_KMRNCTRLSTA_DIAG_NELPBK 0x1000 /* Nearend Loopback mode */ #define E1000_KMRNCTRLSTA_K1_CONFIG 0x7 #define E1000_KMRNCTRLSTA_K1_ENABLE 0x0002 -- 2.46.0