From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB0C0C433FE for ; Tue, 15 Mar 2022 10:08:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346961AbiCOKKA (ORCPT ); Tue, 15 Mar 2022 06:10:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37860 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346950AbiCOKJ7 (ORCPT ); Tue, 15 Mar 2022 06:09:59 -0400 Received: from mx07-00178001.pphosted.com (mx07-00178001.pphosted.com [185.132.182.106]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B2AB03BF96; Tue, 15 Mar 2022 03:08:46 -0700 (PDT) Received: from pps.filterd (m0241204.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 22F4JcYN013011; Tue, 15 Mar 2022 11:08:06 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=selector1; bh=wZLup1066BSl1Hsk/ZF1vSKE25M+uNQ85H+mRhWlPfw=; b=OD5oGWIRM87iRwhfrsGXbAd2cYWCeLngme7W2/UIhqF7KKBQ3DPk/Kw8L3KNdW/QCcql /NOyP7JB1BfjqX4fjS1mUVQu5mxmDWBoupuJsBPUZreIAkmToTLYKHjqWiiVcKElx15Y 78Jug9xNwPIHY5krgWANZqQq44h6JHMoFtHKPvT7tVrjZY8QYYM05B46p+fstSh5jxa9 RTmmFy/JNFNC7X+cib1CuReB8CFCdziF3ASgRHu+FCQODmN/krqHs9xLA73ajl/9m7+9 vximtFti7RGxw5AQ5ieSkulQ6JYCOUDdlRBG9pmmiqjKmv7ZFYAQZQ3MXzKVvQb/Cqlk 6A== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3et63h5krf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 15 Mar 2022 11:08:05 +0100 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id EFC6010002A; Tue, 15 Mar 2022 11:07:42 +0100 (CET) Received: from Webmail-eu.st.com (sfhdag2node2.st.com [10.75.127.5]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id E07B72171CB; Tue, 15 Mar 2022 11:07:42 +0100 (CET) Received: from [10.201.21.172] (10.75.127.47) by SFHDAG2NODE2.st.com (10.75.127.5) with Microsoft SMTP Server (TLS) id 15.0.1497.26; Tue, 15 Mar 2022 11:07:42 +0100 Message-ID: Date: Tue, 15 Mar 2022 11:07:41 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH v2] mmc: mmci: manage MMC_PM_KEEP_POWER per variant config Content-Language: en-US To: Ulf Hansson CC: , , , Christophe Kerello , Linus Walleij , Ludovic Barre , Philipp Zabel , Russell King , Marek Vasut , , Manivannan Sadhasivam , Grzegorz Szymaszek , Christophe ROULLIER-SCND-02 References: <20220314095225.53563-1-yann.gautier@foss.st.com> <20220314125554.190574-1-yann.gautier@foss.st.com> <9e4fbf6a-1309-3aee-fcb0-be7c2c683892@foss.st.com> From: Yann Gautier In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.75.127.47] X-ClientProxiedBy: SFHDAG2NODE2.st.com (10.75.127.5) To SFHDAG2NODE2.st.com (10.75.127.5) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.850,Hydra:6.0.425,FMLib:17.11.64.514 definitions=2022-03-14_14,2022-03-14_02,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/15/22 10:07, Ulf Hansson wrote: > On Mon, 14 Mar 2022 at 17:52, Yann Gautier wrote: >> >> On 3/14/22 17:18, Ulf Hansson wrote: >>> On Mon, 14 Mar 2022 at 15:34, Yann Gautier wrote: >>>> >>>> On 3/14/22 14:03, Ulf Hansson wrote: >>>>> On Mon, 14 Mar 2022 at 13:56, Yann Gautier wrote: >>>>>> >>>>>> Add a disable_keep_power field in variant_data struct. The >>>>>> MMC_PM_KEEP_POWER flag will be enabled if disable_keep_power is not set. >>>>>> It is only set to true for stm32_sdmmc variants. >>>>>> >>>>>> The issue was seen on STM32MP157C-DK2 board, which embeds a wifi chip. >>>>>> It doesn't correctly support low power on this board. The Wifi chip >>>>>> awaits an always-on regulator, but it was connected to v3v3 which is off >>>>>> in low-power sequence. MMC_PM_KEEP_POWER should then be disabled. >>>>> >>>>> Just to make sure I get this correct. >>>>> >>>>> Why can't the regulator stay on during system suspend? The point is, >>>>> we don't need an always on regulator to cope with this. >>>>> >>>>> Kind regards >>>>> Uffe >>>> >>>> Hi Ulf, >>>> >>>> This v3v3 regulator powers most of the devices on this board. So we need >>>> to switch it off to gain power in suspend mode. >>> >>> I see. Thanks for sharing that information. >>> >>> The MMC_PM_KEEP_POWER flag is there to describe what is supported by >>> the platform/host. It doesn't mean that the card *must* stay powered >>> on during system suspend. Instead that depends on whether system >>> wakeup for the SDIO/WiFi is supported too - and if that is enabled by >>> userspace. If not, the regulator will be turned off for the SDIO card >>> during system suspend. >>> >>> Assuming the regulator is implemented as a proper regulator and can >>> remain on during system suspend, the right thing would be to keep the >>> MMC_PM_KEEP_POWER flag around. >>> >>> Kind regards >>> Uffe >>> >> >> OK, but in the wifi driver we use on this platform (brcmfmac), the >> suspend/resume functions (brcmf_ops_sdio_suspend/brcmf_ops_sdio_resume) >> use the flag to check regu was off, and then call probe function during >> resume, to re-init Wifi chip and reload its firmware. > > I had a closer look at the brcmfmac driver, thanks for the pointers. > > In my opinion, I think we should change the brcmfmac driver, so it > decides to power off the SDIO card, unless the WiFi chip is configured > to serve us with system wakeups. > > I can send a patch for brcmfmac that we can try, unless you want to > send it yourself? > Hi Ulf, If you already have an idea of the patch in the brcmfmac driver, can you propose something? We'll be able to test it at our side. Thanks, Yann >> >> >> Best regards, >> Yann > > Kind regards > Uffe > >> >>>> >>>> >>>> Yann >>>> >>>>> >>>>>> >>>>>> The flag can still be enabled through DT property: >>>>>> keep-power-in-suspend. >>>>>> >>>>>> Signed-off-by: Yann Gautier >>>>>> --- >>>>>> Update in v2: >>>>>> Reword commit message to better explain the issue. >>>>>> >>>>>> Resend the patch alone. It was previoulsy in a series [1] for which the >>>>>> other patches will be reworked. >>>>>> >>>>>> [1] https://lore.kernel.org/lkml/20220304135134.47827-1-yann.gautier@foss.st.com/ >>>>>> >>>>>> drivers/mmc/host/mmci.c | 5 ++++- >>>>>> drivers/mmc/host/mmci.h | 1 + >>>>>> 2 files changed, 5 insertions(+), 1 deletion(-) >>>>>> >>>>>> diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c >>>>>> index 45b8608c935c..0e2f2f5d6a52 100644 >>>>>> --- a/drivers/mmc/host/mmci.c >>>>>> +++ b/drivers/mmc/host/mmci.c >>>>>> @@ -274,6 +274,7 @@ static struct variant_data variant_stm32_sdmmc = { >>>>>> .busy_detect = true, >>>>>> .busy_detect_flag = MCI_STM32_BUSYD0, >>>>>> .busy_detect_mask = MCI_STM32_BUSYD0ENDMASK, >>>>>> + .disable_keep_power = true, >>>>>> .init = sdmmc_variant_init, >>>>>> }; >>>>>> >>>>>> @@ -301,6 +302,7 @@ static struct variant_data variant_stm32_sdmmcv2 = { >>>>>> .busy_detect = true, >>>>>> .busy_detect_flag = MCI_STM32_BUSYD0, >>>>>> .busy_detect_mask = MCI_STM32_BUSYD0ENDMASK, >>>>>> + .disable_keep_power = true, >>>>>> .init = sdmmc_variant_init, >>>>>> }; >>>>>> >>>>>> @@ -2172,7 +2174,8 @@ static int mmci_probe(struct amba_device *dev, >>>>>> host->stop_abort.flags = MMC_RSP_R1B | MMC_CMD_AC; >>>>>> >>>>>> /* We support these PM capabilities. */ >>>>>> - mmc->pm_caps |= MMC_PM_KEEP_POWER; >>>>>> + if (!variant->disable_keep_power) >>>>>> + mmc->pm_caps |= MMC_PM_KEEP_POWER; >>>>>> >>>>>> /* >>>>>> * We can do SGIO >>>>>> diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h >>>>>> index e1a9b96a3396..2cad1ef9766a 100644 >>>>>> --- a/drivers/mmc/host/mmci.h >>>>>> +++ b/drivers/mmc/host/mmci.h >>>>>> @@ -361,6 +361,7 @@ struct variant_data { >>>>>> u32 opendrain; >>>>>> u8 dma_lli:1; >>>>>> u32 stm32_idmabsize_mask; >>>>>> + u8 disable_keep_power:1; >>>>>> void (*init)(struct mmci_host *host); >>>>>> }; >>>>>> >>>>>> -- >>>>>> 2.25.1 >>>>>> >>>> >>