From 948264879b6894dc389a44b99fae4f0b72932619 Mon Sep 17 00:00:00 2001 From: Todd Fujinaka Date: Thu, 10 Jul 2014 01:47:15 -0700 Subject: igb: Workaround for i210 Errata 25: Slow System Clock On some devices, the internal PLL circuit occasionally provides the wrong clock frequency after power up. The probability of failure is less than one failure per 1000 power cycles. When the failure occurs, the internal clock frequency is around 1/20 of the correct frequency. Cc: stable Signed-off-by: Todd Fujinaka Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller --- drivers/net/ethernet/intel/igb/e1000_i210.c | 66 +++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) (limited to 'drivers/net/ethernet/intel/igb/e1000_i210.c') diff --git a/drivers/net/ethernet/intel/igb/e1000_i210.c b/drivers/net/ethernet/intel/igb/e1000_i210.c index 337161f440dd..65d931669f81 100644 --- a/drivers/net/ethernet/intel/igb/e1000_i210.c +++ b/drivers/net/ethernet/intel/igb/e1000_i210.c @@ -834,3 +834,69 @@ s32 igb_init_nvm_params_i210(struct e1000_hw *hw) } return ret_val; } + +/** + * igb_pll_workaround_i210 + * @hw: pointer to the HW structure + * + * Works around an errata in the PLL circuit where it occasionally + * provides the wrong clock frequency after power up. + **/ +s32 igb_pll_workaround_i210(struct e1000_hw *hw) +{ + s32 ret_val; + u32 wuc, mdicnfg, ctrl, ctrl_ext, reg_val; + u16 nvm_word, phy_word, pci_word, tmp_nvm; + int i; + + /* Get and set needed register values */ + wuc = rd32(E1000_WUC); + mdicnfg = rd32(E1000_MDICNFG); + reg_val = mdicnfg & ~E1000_MDICNFG_EXT_MDIO; + wr32(E1000_MDICNFG, reg_val); + + /* Get data from NVM, or set default */ + ret_val = igb_read_invm_word_i210(hw, E1000_INVM_AUTOLOAD, + &nvm_word); + if (ret_val) + nvm_word = E1000_INVM_DEFAULT_AL; + tmp_nvm = nvm_word | E1000_INVM_PLL_WO_VAL; + for (i = 0; i < E1000_MAX_PLL_TRIES; i++) { + /* check current state directly from internal PHY */ + igb_read_phy_reg_gs40g(hw, (E1000_PHY_PLL_FREQ_PAGE | + E1000_PHY_PLL_FREQ_REG), &phy_word); + if ((phy_word & E1000_PHY_PLL_UNCONF) + != E1000_PHY_PLL_UNCONF) { + ret_val = 0; + break; + } else { + ret_val = -E1000_ERR_PHY; + } + /* directly reset the internal PHY */ + ctrl = rd32(E1000_CTRL); + wr32(E1000_CTRL, ctrl|E1000_CTRL_PHY_RST); + + ctrl_ext = rd32(E1000_CTRL_EXT); + ctrl_ext |= (E1000_CTRL_EXT_PHYPDEN | E1000_CTRL_EXT_SDLPE); + wr32(E1000_CTRL_EXT, ctrl_ext); + + wr32(E1000_WUC, 0); + reg_val = (E1000_INVM_AUTOLOAD << 4) | (tmp_nvm << 16); + wr32(E1000_EEARBC_I210, reg_val); + + igb_read_pci_cfg(hw, E1000_PCI_PMCSR, &pci_word); + pci_word |= E1000_PCI_PMCSR_D3; + igb_write_pci_cfg(hw, E1000_PCI_PMCSR, &pci_word); + usleep_range(1000, 2000); + pci_word &= ~E1000_PCI_PMCSR_D3; + igb_write_pci_cfg(hw, E1000_PCI_PMCSR, &pci_word); + reg_val = (E1000_INVM_AUTOLOAD << 4) | (nvm_word << 16); + wr32(E1000_EEARBC_I210, reg_val); + + /* restore WUC register */ + wr32(E1000_WUC, wuc); + } + /* restore MDICNFG setting */ + wr32(E1000_MDICNFG, mdicnfg); + return ret_val; +} -- cgit v1.2.3