RE: [PATCH v5 3/4] Revert "e1000e: disable s0ix entry and exit flows for ME systems"

[Shen, Yijun]

> -----Original Message-----
> From: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>
> Sent: Tuesday, December 15, 2020 3:30 AM
> To: Jeff Kirsher; Tony Nguyen; intel-wired-lan@xxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx; Netdev; Alexander Duyck; Jakub Kicinski;
> Sasha Netfin; Aaron Brown; Stefan Assmann; David Miller;
> darcari@xxxxxxxxxx; Shen, Yijun; Yuan, Perry;
> anthony.wong@xxxxxxxxxxxxx; Hans de Goede; Limonciello, Mario
> Subject: [PATCH v5 3/4] Revert "e1000e: disable s0ix entry and exit flows for
> ME systems"
> 
> commit e086ba2fccda ("e1000e: disable s0ix entry and exit flows for ME
> systems") disabled s0ix flows for systems that have various incarnations of
> the i219-LM ethernet controller.  This changed caused power consumption
> regressions on the following shipping Dell Comet Lake based laptops:
> * Latitude 5310
> * Latitude 5410
> * Latitude 5410
> * Latitude 5510
> * Precision 3550
> * Latitude 5411
> * Latitude 5511
> * Precision 3551
> * Precision 7550
> * Precision 7750
> 
> This commit was introduced because of some regressions on certain
> Thinkpad laptops.  This comment was potentially caused by an earlier
> commit 632fbd5eb5b0e ("e1000e: fix S0ix flows for cable connected case").
> or it was possibly caused by a system not meeting platform architectural
> requirements for low power consumption.  Other changes made in the driver
> with extended timeouts are expected to make the driver more impervious to
> platform firmware behavior.
> 
> Fixes: e086ba2fccda ("e1000e: disable s0ix entry and exit flows for ME
> systems")
> Reviewed-by: Alexander Duyck <alexander.duyck@xxxxxxxxx>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxxx>

Verified this series patches with Dell Systems.

Tested-By: Yijun Shen <Yijun.shen@xxxxxxxx>

> ---
>  drivers/net/ethernet/intel/e1000e/netdev.c | 45 +---------------------
>  1 file changed, 2 insertions(+), 43 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c
> b/drivers/net/ethernet/intel/e1000e/netdev.c
> index 6588f5d4a2be..b9800ba2006c 100644
> --- a/drivers/net/ethernet/intel/e1000e/netdev.c
> +++ b/drivers/net/ethernet/intel/e1000e/netdev.c
> @@ -103,45 +103,6 @@ static const struct e1000_reg_info
> e1000_reg_info_tbl[] = {
>  	{0, NULL}
>  };
> 
> -struct e1000e_me_supported {
> -	u16 device_id;		/* supported device ID */
> -};
> -
> -static const struct e1000e_me_supported me_supported[] = {
> -	{E1000_DEV_ID_PCH_LPT_I217_LM},
> -	{E1000_DEV_ID_PCH_LPTLP_I218_LM},
> -	{E1000_DEV_ID_PCH_I218_LM2},
> -	{E1000_DEV_ID_PCH_I218_LM3},
> -	{E1000_DEV_ID_PCH_SPT_I219_LM},
> -	{E1000_DEV_ID_PCH_SPT_I219_LM2},
> -	{E1000_DEV_ID_PCH_LBG_I219_LM3},
> -	{E1000_DEV_ID_PCH_SPT_I219_LM4},
> -	{E1000_DEV_ID_PCH_SPT_I219_LM5},
> -	{E1000_DEV_ID_PCH_CNP_I219_LM6},
> -	{E1000_DEV_ID_PCH_CNP_I219_LM7},
> -	{E1000_DEV_ID_PCH_ICP_I219_LM8},
> -	{E1000_DEV_ID_PCH_ICP_I219_LM9},
> -	{E1000_DEV_ID_PCH_CMP_I219_LM10},
> -	{E1000_DEV_ID_PCH_CMP_I219_LM11},
> -	{E1000_DEV_ID_PCH_CMP_I219_LM12},
> -	{E1000_DEV_ID_PCH_TGP_I219_LM13},
> -	{E1000_DEV_ID_PCH_TGP_I219_LM14},
> -	{E1000_DEV_ID_PCH_TGP_I219_LM15},
> -	{0}
> -};
> -
> -static bool e1000e_check_me(u16 device_id) -{
> -	struct e1000e_me_supported *id;
> -
> -	for (id = (struct e1000e_me_supported *)me_supported;
> -	     id->device_id; id++)
> -		if (device_id == id->device_id)
> -			return true;
> -
> -	return false;
> -}
> -
>  /**
>   * __ew32_prepare - prepare to write to MAC CSR register on certain parts
>   * @hw: pointer to the HW structure
> @@ -6974,8 +6935,7 @@ static __maybe_unused int
> e1000e_pm_suspend(struct device *dev)
>  		e1000e_pm_thaw(dev);
>  	} else {
>  		/* Introduce S0ix implementation */
> -		if (hw->mac.type >= e1000_pch_cnp &&
> -		    !e1000e_check_me(hw->adapter->pdev->device))
> +		if (hw->mac.type >= e1000_pch_cnp)
>  			e1000e_s0ix_entry_flow(adapter);
>  	}
> 
> @@ -6991,8 +6951,7 @@ static __maybe_unused int
> e1000e_pm_resume(struct device *dev)
>  	int rc;
> 
>  	/* Introduce S0ix implementation */
> -	if (hw->mac.type >= e1000_pch_cnp &&
> -	    !e1000e_check_me(hw->adapter->pdev->device))
> +	if (hw->mac.type >= e1000_pch_cnp)
>  		e1000e_s0ix_exit_flow(adapter);
> 
>  	rc = __e1000_resume(pdev);
> --
> 2.25.1