From e08f626b33eb636dbf38b21618ab32b7fd8e1ec4 Mon Sep 17 00:00:00 2001 From: Bruce Allan Date: Wed, 20 Feb 2013 03:06:34 +0000 Subject: [PATCH] e1000e: workaround DMA unit hang on I218 At 1000Mbps link speed, one of the MAC's internal clocks can be stopped for up to 4us when entering K1 (a power mode of the MAC-PHY interconnect). If the MAC is waiting for completion indications for 2 DMA write requests into Host memory (e.g. descriptor writeback or Rx packet writing) and the indications occur while the clock is stopped, both indications will be missed by the MAC causing the MAC to wait for the completion indications and be unable to generate further DMA write requests. This results in an apparent hardware hang. Work-around the issue by disabling the de-assertion of the clock request when 1000Mbps link is acquired (K1 must be disabled while doing this). Signed-off-by: Bruce Allan Tested-by: Jeff Pieper Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/e1000e/ich8lan.c | 71 ++++++++++++++++++++- drivers/net/ethernet/intel/e1000e/ich8lan.h | 2 + drivers/net/ethernet/intel/e1000e/regs.h | 1 + 3 files changed, 73 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c b/drivers/net/ethernet/intel/e1000e/ich8lan.c index dff7bff8b8e..121a865c7fb 100644 --- a/drivers/net/ethernet/intel/e1000e/ich8lan.c +++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c @@ -781,6 +781,59 @@ release: return ret_val; } +/** + * e1000_k1_workaround_lpt_lp - K1 workaround on Lynxpoint-LP + * @hw: pointer to the HW structure + * @link: link up bool flag + * + * When K1 is enabled for 1Gbps, the MAC can miss 2 DMA completion indications + * preventing further DMA write requests. Workaround the issue by disabling + * the de-assertion of the clock request when in 1Gpbs mode. + **/ +static s32 e1000_k1_workaround_lpt_lp(struct e1000_hw *hw, bool link) +{ + u32 fextnvm6 = er32(FEXTNVM6); + s32 ret_val = 0; + + if (link && (er32(STATUS) & E1000_STATUS_SPEED_1000)) { + u16 kmrn_reg; + + ret_val = hw->phy.ops.acquire(hw); + if (ret_val) + return ret_val; + + ret_val = + e1000e_read_kmrn_reg_locked(hw, E1000_KMRNCTRLSTA_K1_CONFIG, + &kmrn_reg); + if (ret_val) + goto release; + + ret_val = + e1000e_write_kmrn_reg_locked(hw, + E1000_KMRNCTRLSTA_K1_CONFIG, + kmrn_reg & + ~E1000_KMRNCTRLSTA_K1_ENABLE); + if (ret_val) + goto release; + + usleep_range(10, 20); + + ew32(FEXTNVM6, fextnvm6 | E1000_FEXTNVM6_REQ_PLL_CLK); + + ret_val = + e1000e_write_kmrn_reg_locked(hw, + E1000_KMRNCTRLSTA_K1_CONFIG, + kmrn_reg); +release: + hw->phy.ops.release(hw); + } else { + /* clear FEXTNVM6 bit 8 on link down or 10/100 */ + ew32(FEXTNVM6, fextnvm6 & ~E1000_FEXTNVM6_REQ_PLL_CLK); + } + + return ret_val; +} + /** * e1000_check_for_copper_link_ich8lan - Check for link (Copper) * @hw: pointer to the HW structure @@ -818,6 +871,14 @@ static s32 e1000_check_for_copper_link_ich8lan(struct e1000_hw *hw) return ret_val; } + /* Work-around I218 hang issue */ + if ((hw->adapter->pdev->device == E1000_DEV_ID_PCH_LPTLP_I218_LM) || + (hw->adapter->pdev->device == E1000_DEV_ID_PCH_LPTLP_I218_V)) { + ret_val = e1000_k1_workaround_lpt_lp(hw, link); + if (ret_val) + return ret_val; + } + /* Clear link partner's EEE ability */ hw->dev_spec.ich8lan.eee_lp_ability = 0; @@ -3954,8 +4015,16 @@ void e1000_suspend_workarounds_ich8lan(struct e1000_hw *hw) phy_ctrl = er32(PHY_CTRL); phy_ctrl |= E1000_PHY_CTRL_GBE_DISABLE; + if (hw->phy.type == e1000_phy_i217) { - u16 phy_reg; + u16 phy_reg, device_id = hw->adapter->pdev->device; + + if ((device_id == E1000_DEV_ID_PCH_LPTLP_I218_LM) || + (device_id == E1000_DEV_ID_PCH_LPTLP_I218_V)) { + u32 fextnvm6 = er32(FEXTNVM6); + + ew32(FEXTNVM6, fextnvm6 & ~E1000_FEXTNVM6_REQ_PLL_CLK); + } ret_val = hw->phy.ops.acquire(hw); if (ret_val) diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.h b/drivers/net/ethernet/intel/e1000e/ich8lan.h index b6d3174d7d2..8bf4655c2e1 100644 --- a/drivers/net/ethernet/intel/e1000e/ich8lan.h +++ b/drivers/net/ethernet/intel/e1000e/ich8lan.h @@ -92,6 +92,8 @@ #define E1000_FEXTNVM4_BEACON_DURATION_8USEC 0x7 #define E1000_FEXTNVM4_BEACON_DURATION_16USEC 0x3 +#define E1000_FEXTNVM6_REQ_PLL_CLK 0x00000100 + #define PCIE_ICH8_SNOOP_ALL PCIE_NO_SNOOP_ALL #define E1000_ICH_RAR_ENTRIES 7 diff --git a/drivers/net/ethernet/intel/e1000e/regs.h b/drivers/net/ethernet/intel/e1000e/regs.h index 794fe149766..a7e6a3e3725 100644 --- a/drivers/net/ethernet/intel/e1000e/regs.h +++ b/drivers/net/ethernet/intel/e1000e/regs.h @@ -42,6 +42,7 @@ #define E1000_FEXTNVM 0x00028 /* Future Extended NVM - RW */ #define E1000_FEXTNVM3 0x0003C /* Future Extended NVM 3 - RW */ #define E1000_FEXTNVM4 0x00024 /* Future Extended NVM 4 - RW */ +#define E1000_FEXTNVM6 0x00010 /* Future Extended NVM 6 - RW */ #define E1000_FEXTNVM7 0x000E4 /* Future Extended NVM 7 - RW */ #define E1000_FCT 0x00030 /* Flow Control Type - RW */ #define E1000_VET 0x00038 /* VLAN Ether Type - RW */ -- 2.41.0