Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Message-ID: <04ed8307-ab1f-59d6-4454-c759ce4a453b@intel.com>
Date:   Tue, 26 Oct 2021 11:47:55 +0300
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101
 Firefox/91.0 Thunderbird/91.2.0
Subject: Re: [PATCH v2] e1000e: Add a delay to let ME unconfigure s0ix when
 DPG_EXIT_DONE is already flagged
Content-Language: en-US
To:     Kai-Heng Feng <kai.heng.feng@canonical.com>,
        <jesse.brandeburg@intel.com>, <anthony.l.nguyen@intel.com>
CC:     <acelan.kao@canonical.com>,
        "David S. Miller" <davem@davemloft.net>,
        "Jakub Kicinski" <kuba@kernel.org>,
        Dima Ruinskiy <dima.ruinskiy@intel.com>,
        <intel-wired-lan@lists.osuosl.org>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>,
        "Kraus, NechamaX" <nechamax.kraus@linux.intel.com>,
        "Fuxbrumer, Devora" <devora.fuxbrumer@intel.com>,
        "Avivi, Amir" <amir.avivi@intel.com>
References: <20211026065112.1366205-1-kai.heng.feng@canonical.com>
From:   Sasha Neftin <sasha.neftin@intel.com>
In-Reply-To: <20211026065112.1366205-1-kai.heng.feng@canonical.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?dXpvcHdTQ2tybW1iMTU4M1lNMUcvK0JCK3NUZTdWTzJkZUVGRGVRSjF3NHhi?=
 =?utf-8?B?Qzg2OFN1ekl0NHJVc1pwOVo4c0RrMXg5RXVtWUFna24xQkdzZlhkWnFieE5v?=
 =?utf-8?B?cU9YUGRoNWhKU3I5UjJFMkpCb0grZVlucDdjQjlOKzNRcXdUcThuSkMxbjJo?=
 =?utf-8?B?Wk1FT3d3RzIwSmk5WGkvalkrZ2VrckZLT0lPYXVJR1dZdnh2RzVOOUVPeW1L?=
 =?utf-8?B?eXZHalpZY2oveHhBWGhRUjc1UUNRWW54VzRHaVNaZ3VONjBvWWk3NU5HOW9v?=
 =?utf-8?B?NllkZ2pvMnNMeFBweGN1elZDZlBWYXdZMXJtVXMwYWl2WmwzVEtWMWUzcW0x?=
 =?utf-8?B?Q0VERnNkaCtHRVB0UnhXQ2xicUdHY29xZk9DSUlwb2FGVzc5VGVGNzcxcVAv?=
 =?utf-8?B?U2VvamQ3c0Z3amJ0SnlmK1ZSRnJoaFE0RXplNnZJWmMrbVl4Y2ZNTWtoL3RD?=
 =?utf-8?B?UEN2akwzMDFTRkczMHd3ckRMU25ISm1vRlh0MEFtQm1sRFJvZnZFWWdZZEtj?=
 =?utf-8?B?bnJkTmVFaUhBVERSUXdxcEQ1N0NQNWp2QmJDU0NxMDNLUVhNSzJaNkFuUnQx?=
 =?utf-8?B?UGUvc1hDeUlGb3VIYUlxQmtQOXBaWTNkRzVFTmVJNlM2MTIxRUJvUXlxVzIx?=
 =?utf-8?B?akxnanV3TEpiZU5LeWQxeTJIZEYwdkZYTTgwM1M0VlljampGUGZabTZkbEhP?=
 =?utf-8?B?aU9JVngxQVBQS3ZJSVBLRGUvU2d6M2FLaTRia0trclFxRUxvZVBZZ0FZRk1X?=
 =?utf-8?B?OW1iN3hLdjIzWWpvMWJYWlVJQkFGN2drY3RTelF6bHdqQ05yY1M1UjY1Ympy?=
 =?utf-8?B?cHFxRTBvREt5TUppaytndTRvdGdMeTRiUDc2UjVRRjZYTkpXdExQRS96N3NJ?=
 =?utf-8?B?NnBLYkgxSDdpczhFVTlaVHNDajl1eHNHU1VsTDJ6MEhscmlNc25DZEJVYU4w?=
 =?utf-8?B?N21EMUErMWtYbGoxdjNHOU5LdGR1UU9vWVFvM0pEK3hBSW01OFpBWDRoQ05P?=
 =?utf-8?B?b1JmaEdkQ0wwNW9NMy9CWG5Hdm9hdWNQcis5Y0dPMkhvU3Iyc0dpd2hUeHNH?=
 =?utf-8?B?TUdHaWpNcCt1OEF6WTM2Rnpyb1dlTDZXREhCR0VJV2Jpc1pSL2p6NE15cGF6?=
 =?utf-8?B?aS9EeFJRMDROTzNkN3FUZEF1cm15MHFsWUpCSnp3TFY5VjM0Z2xDcnpaaDNN?=
 =?utf-8?B?dHQrSHFsdkNzM25aRTBXOVlMdXRPZEJwOHlseDd6ZG1wTmE5OHhySTdHUzFv?=
 =?utf-8?B?Z3pMOXAvaXVOM29ReG43dFJXT2lab3ZUUGQ4L1NUR3pLSEJmRWp2TkprQzcv?=
 =?utf-8?B?LzM5ZXpBYU9wWTlkaVdoVVcxZTdpOHB4b0dKTHpONXVZYndRSjJXZ1Y0UFpq?=
 =?utf-8?B?dlI2dVg5SkJIbGtWY3JpS2VET2xXTFQzMFNLOFplNVppMDhQRkh2OS9pTjBG?=
 =?utf-8?B?ZjVGSG5hdzc4bWg5aVhYdUtBaElRSzNmSWFveklWRFlpMnFwdDB3UmpObjdZ?=
 =?utf-8?B?RU9nUG9xNkhDUlZVRndldHpMYzk0cFo4Qmw4WklITEhqYXA5cVplRFRpMXRl?=
 =?utf-8?B?ZzJrTEFKekdvdG5abG1lK1VuSmdXZWV2UzJTVElZRU1mUFB5K2ZHaWlJaE5F?=
 =?utf-8?B?ZzBXOVZETnpSK3RCMjAxeDk0cHhlNC9MTUlWak00NXh0RUtmVHM1RGw5aUVi?=
 =?utf-8?B?VlVrRlRhOVRtWEpCSU5jREh3cXh1ZW0wVlk3M2NzMDRGa1l1emFIVG9tN2pJ?=
 =?utf-8?B?cHpYeER0ZUgxV24vSitlTXM2eUtOWUZ6ZDZvaHBtemFZOTliem1QQUJiMVB6?=
 =?utf-8?B?SnhhcGFYdkhadEVuOG1UNkhyM1F5cGtmV2VNaVlRQlJDb3JVR1FZU2lXb1JV?=
 =?utf-8?B?bU1NSG45ZEJVajBGWlJxVkRmc0g5OElEMC9lVlZJc2RkQVZIZ0svdFVXKzcz?=
 =?utf-8?B?eE5IOCtoQ05yYy9NcThXeGY5Lzhrek5XVTd3aTBOcXp4T2JBTHBUckhodDBw?=
 =?utf-8?B?MmFMK0NUZTcyS2ZaNWdOZFQrZ1pYaUt0MWo5eVVONWV6T0tQWVVSK3hXOEt2?=
 =?utf-8?B?ZlVFeE5DcllTRE5BcG56M1lkSFArU2N3OFVVRzZwU3ltSE16T1dGRFNTTlBn?=
 =?utf-8?B?Rm9ield6NmQrWkc1NThGbEd0cnlQb2xROTBTbktlUW1pc2lQVUpPUHVoWHMy?=
 =?utf-8?Q?pwZeHoKMV+XYDwreTtn/uOA=3D?=
X-MS-Exchange-CrossTenant-Network-Message-Id: abc2f773-d397-4e70-65b1-08d9985d52db
X-MS-Exchange-CrossTenant-AuthSource: CO1PR11MB4787.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 26 Oct 2021 08:48:04.2173
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: dZM5CNKs/FbrLo3trZygLmwtNJT9anXKVeoPJS4p4vcJ7Jnao9fOk3bc41mh6i5pmRyzYHAK94NeESyflMTbNw==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MWHPR11MB1565
X-OriginatorOrg: intel.com
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 10/26/2021 09:51, Kai-Heng Feng wrote:
> On some ADL platforms, DPG_EXIT_DONE is always flagged so e1000e resume
> polling logic doesn't wait until ME really unconfigures s0ix.
> 
> So check DPG_EXIT_DONE before issuing EXIT_DPG, and if it's already
> flagged, wait for 1 second to let ME unconfigure s0ix.
> 
> Fixes: 3e55d231716e ("e1000e: Add handshake with the CSME to support S0ix")
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=214821
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> ---
> v2:
>   Add missing "Fixes:" tag
> 
>   drivers/net/ethernet/intel/e1000e/netdev.c | 7 +++++++
>   1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
> index 44e2dc8328a22..cd81ba00a6bc9 100644
> --- a/drivers/net/ethernet/intel/e1000e/netdev.c
> +++ b/drivers/net/ethernet/intel/e1000e/netdev.c
> @@ -6493,14 +6493,21 @@ static void e1000e_s0ix_exit_flow(struct e1000_adapter *adapter)
>   	u32 mac_data;
>   	u16 phy_data;
>   	u32 i = 0;
> +	bool dpg_exit_done;
>   
>   	if (er32(FWSM) & E1000_ICH_FWSM_FW_VALID) {
> +		dpg_exit_done = er32(EXFWSM) & E1000_EXFWSM_DPG_EXIT_DONE;
>   		/* Request ME unconfigure the device from S0ix */
>   		mac_data = er32(H2ME);
>   		mac_data &= ~E1000_H2ME_START_DPG;
>   		mac_data |= E1000_H2ME_EXIT_DPG;
>   		ew32(H2ME, mac_data);
>   
> +		if (dpg_exit_done) {
> +			e_warn("DPG_EXIT_DONE is already flagged. This is a firmware bug\n");
> +			msleep(1000);
> +		}
Thanks for working on the enablement.
The delay approach is fragile. We need to work with CSME folks to 
understand why _DPG_EXIT_DONE indication is wrong on some ADL platforms.
Could you provide CSME/BIOS version? dmidecode -t 0 and cat 
/sys/class/mei/mei0/fw_ver
>   		/* Poll up to 2.5 seconds for ME to unconfigure DPG.
>   		 * If this takes more than 1 second, show a warning indicating a
>   		 * firmware bug
>