From 639e298f432fb058a9496ea16863f53b1ce935fe Mon Sep 17 00:00:00 2001 From: Sasha Neftin Date: Wed, 22 Sep 2021 09:55:42 +0300 Subject: [PATCH] e1000e: Fix packet loss on Tiger Lake and later Update the HW MAC initialization flow. Do not gate DMA clock from the modPHY block. Keeping this clock will prevent dropped packets sent in burst mode on the Kumeran interface. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=213651 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=213377 Fixes: fb776f5d57ee ("e1000e: Add support for Tiger Lake") Signed-off-by: Sasha Neftin Tested-by: Mark Pearson Tested-by: Nechama Kraus Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/e1000e/ich8lan.c | 11 ++++++++++- drivers/net/ethernet/intel/e1000e/ich8lan.h | 3 +++ 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c b/drivers/net/ethernet/intel/e1000e/ich8lan.c index 66d7196310e2..5e4fc9b4e2ad 100644 --- a/drivers/net/ethernet/intel/e1000e/ich8lan.c +++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c @@ -4813,7 +4813,7 @@ static s32 e1000_reset_hw_ich8lan(struct e1000_hw *hw) static s32 e1000_init_hw_ich8lan(struct e1000_hw *hw) { struct e1000_mac_info *mac = &hw->mac; - u32 ctrl_ext, txdctl, snoop; + u32 ctrl_ext, txdctl, snoop, fflt_dbg; s32 ret_val; u16 i; @@ -4872,6 +4872,15 @@ static s32 e1000_init_hw_ich8lan(struct e1000_hw *hw) snoop = (u32)~(PCIE_NO_SNOOP_ALL); e1000e_set_pcie_no_snoop(hw, snoop); + /* Enable workaround for packet loss issue on TGP PCH + * Do not gate DMA clock from the modPHY block + */ + if (mac->type >= e1000_pch_tgp) { + fflt_dbg = er32(FFLT_DBG); + fflt_dbg |= E1000_FFLT_DBG_DONT_GATE_WAKE_DMA_CLK; + ew32(FFLT_DBG, fflt_dbg); + } + ctrl_ext = er32(CTRL_EXT); ctrl_ext |= E1000_CTRL_EXT_RO_DIS; ew32(CTRL_EXT, ctrl_ext); diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.h b/drivers/net/ethernet/intel/e1000e/ich8lan.h index d6a092e5ee74..2504b11c3169 100644 --- a/drivers/net/ethernet/intel/e1000e/ich8lan.h +++ b/drivers/net/ethernet/intel/e1000e/ich8lan.h @@ -289,6 +289,9 @@ /* Proprietary Latency Tolerance Reporting PCI Capability */ #define E1000_PCI_LTR_CAP_LPT 0xA8 +/* Don't gate wake DMA clock */ +#define E1000_FFLT_DBG_DONT_GATE_WAKE_DMA_CLK 0x1000 + void e1000e_write_protect_nvm_ich8lan(struct e1000_hw *hw); void e1000e_set_kmrn_lock_loss_workaround_ich8lan(struct e1000_hw *hw, bool state); -- 2.20.1