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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9949C433E0 for ; Wed, 17 Jun 2020 14:16:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92647214DB for ; Wed, 17 Jun 2020 14:16:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="puyh6IIB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727049AbgFQOQj (ORCPT ); Wed, 17 Jun 2020 10:16:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57080 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727047AbgFQOQi (ORCPT ); Wed, 17 Jun 2020 10:16:38 -0400 Received: from mail-vs1-xe41.google.com (mail-vs1-xe41.google.com [IPv6:2607:f8b0:4864:20::e41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00E43C0613ED for ; Wed, 17 Jun 2020 07:16:37 -0700 (PDT) Received: by mail-vs1-xe41.google.com with SMTP id c1so1445615vsc.11 for ; Wed, 17 Jun 2020 07:16:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=gSW8BPLoltx1w5hCbo9mZt1Y0aly6PeCbW4FnOcx58o=; b=puyh6IIB9om+v34S6yPC5lV02PiuqvGWHI3pSFUkPQpUCe8Phx1XKP3aXPtyxAhmZD bxgQBCYv936XR5J8jgI0ilTX9BSW0sl7yZHQQ0AWFYV8Uf7QrN3TEZzQj4PKd0x4yiru ExmAVLgPbgDMHk14tMuz226+dGwcVxVfXgrZywCplVewC+xbahBxzlBWXNUOwT33t9a/ P+BTFl7MjpGE/1vU2b+QalrVnNe2dqvEAOyBxNTj3CdupxQMtYtgnWXGJ3yp5KVy/nUp F7rR6aJ4XAXz1F4OQE4jVaph7ELqsAWlVSOn/W/BcgUao37f14paqOwOZaIxnestPX2J /xMw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=gSW8BPLoltx1w5hCbo9mZt1Y0aly6PeCbW4FnOcx58o=; b=GizV4iL2fZbm39dSbbogaAovWq4uPTq/Dpil0VpFtEtuwtjGQLcebexdG8Yi7T9IUE Ykwb6VFyhkDaDimyW0q3TOkySAxJhBGYzPImI6/5FiC6fPKAPvpOSy0lRvMKDEg+rNHe DyNp+yYYzI6wJel5QGpuMwTrYvrDlrwtTkDT+cRvigUle0CAyvatdFGv34ovT6Y/hepP RdJPGhFJqme/d/PN9+1HdjvI1Po9eJrVz737rd1OOoujXf7541i9EmPR1cKlXIrgyltK Hob7MIEWomsWFQhpAABitqlL2RSb3/zOrdygdr0OAgiZ+NzsSwLCFsE25dZ2s70zU7i7 oG5g== X-Gm-Message-State: AOAM532PxfBnGDD3vGN+AQWS9n+Pibo27CjnU6A7CeSLV0efnxnFS5M/ oaXXg+aCXLvuNo5jS8HLCoDLJWByFrho3G/FK2iq8w== X-Google-Smtp-Source: ABdhPJzmC8gc3+JMfV9wCocw1ivFjymC2aPSQ/lfOhTELQ8oMXdIviDwMW4WplrnBCcbqAC/slVDAmnXL6IsmyqJ4Wo= X-Received: by 2002:a05:6102:18e:: with SMTP id r14mr6059812vsq.200.1592403397046; Wed, 17 Jun 2020 07:16:37 -0700 (PDT) MIME-Version: 1.0 References: <1589541535-8523-1-git-send-email-vbadigan@codeaurora.org> <1592321779-28556-1-git-send-email-vbadigan@codeaurora.org> <1592321779-28556-3-git-send-email-vbadigan@codeaurora.org> <40b03630-cdbc-50ee-e483-8ff919f76fb5@codeaurora.org> In-Reply-To: <40b03630-cdbc-50ee-e483-8ff919f76fb5@codeaurora.org> From: Ulf Hansson Date: Wed, 17 Jun 2020 16:16:00 +0200 Message-ID: Subject: Re: [PATCH V4 2/2] mmc: sdhci-msm: Use internal voltage control To: Veerabhadrarao Badiganti Cc: Adrian Hunter , Bjorn Andersson , "linux-mmc@vger.kernel.org" , Linux Kernel Mailing List , linux-arm-msm , Asutosh Das , Vijay Viswanath , Andy Gross Content-Type: text/plain; charset="UTF-8" Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Wed, 17 Jun 2020 at 14:46, Veerabhadrarao Badiganti wrote: > > Thanks for comments Uffe. > > On 6/17/2020 3:04 PM, Ulf Hansson wrote: > > On Tue, 16 Jun 2020 at 17:38, Veerabhadrarao Badiganti > > wrote: > >> On qcom SD host controllers voltage switching be done after the HW > >> is ready for it. The HW informs its readiness through power irq. > >> The voltage switching should happen only then. > >> > >> Use the internal voltage switching and then control the voltage > >> switching using power irq. > >> > >> IO-bus supply of eMMC would be kept always-on. So set the load > >> for this supply to configure it in LPM when eMMC is suspend state > >> and in HPM when eMMC is active. > >> > >> Co-developed-by: Asutosh Das > >> Signed-off-by: Asutosh Das > >> Co-developed-by: Vijay Viswanath > >> Signed-off-by: Vijay Viswanath > >> Co-developed-by: Veerabhadrarao Badiganti > >> Signed-off-by: Veerabhadrarao Badiganti > >> --- > >> drivers/mmc/host/sdhci-msm.c | 208 +++++++++++++++++++++++++++++++++++++++++-- > >> 1 file changed, 199 insertions(+), 9 deletions(-) > >> > >> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c > >> index 15c42b059240..8297b2142748 100644 > >> --- a/drivers/mmc/host/sdhci-msm.c > >> +++ b/drivers/mmc/host/sdhci-msm.c > >> @@ -37,7 +37,9 @@ > >> #define CORE_PWRCTL_IO_LOW BIT(2) > >> #define CORE_PWRCTL_IO_HIGH BIT(3) > >> #define CORE_PWRCTL_BUS_SUCCESS BIT(0) > >> +#define CORE_PWRCTL_BUS_FAIL BIT(1) > >> #define CORE_PWRCTL_IO_SUCCESS BIT(2) > >> +#define CORE_PWRCTL_IO_FAIL BIT(3) > >> #define REQ_BUS_OFF BIT(0) > >> #define REQ_BUS_ON BIT(1) > >> #define REQ_IO_LOW BIT(2) > >> @@ -127,6 +129,9 @@ > >> /* Timeout value to avoid infinite waiting for pwr_irq */ > >> #define MSM_PWR_IRQ_TIMEOUT_MS 5000 > >> > >> +/* Max load for eMMC Vdd-io supply */ > >> +#define MMC_VQMMC_MAX_LOAD_UA 325000 > >> + > >> #define msm_host_readl(msm_host, host, offset) \ > >> msm_host->var_ops->msm_readl_relaxed(host, offset) > >> > >> @@ -278,6 +283,7 @@ struct sdhci_msm_host { > >> bool uses_tassadar_dll; > >> u32 dll_config; > >> u32 ddr_config; > >> + bool vqmmc_enabled; > >> }; > >> > >> static const struct sdhci_msm_offset *sdhci_priv_msm_offset(struct sdhci_host *host) > >> @@ -1346,6 +1352,88 @@ static void sdhci_msm_set_uhs_signaling(struct sdhci_host *host, > >> sdhci_msm_hs400(host, &mmc->ios); > >> } > >> > >> +static int sdhci_msm_set_vmmc(struct mmc_host *mmc) > >> +{ > >> + if (IS_ERR(mmc->supply.vmmc)) > >> + return 0; > >> + > >> + return mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, mmc->ios.vdd); > >> +} > >> + > >> +static int msm_toggle_vqmmc(struct sdhci_msm_host *msm_host, > >> + struct mmc_host *mmc, bool level) > >> +{ > >> + int ret; > >> + struct mmc_ios ios; > >> + > >> + if (msm_host->vqmmc_enabled == level) > >> + return 0; > >> + > >> + if (level) { > >> + /* Set the IO voltage regulator to default voltage level */ > >> + if (msm_host->caps_0 & CORE_3_0V_SUPPORT) > >> + ios.signal_voltage = MMC_SIGNAL_VOLTAGE_330; > >> + else if (msm_host->caps_0 & CORE_1_8V_SUPPORT) > >> + ios.signal_voltage = MMC_SIGNAL_VOLTAGE_180; > >> + > >> + if (msm_host->caps_0 & CORE_VOLT_SUPPORT) { > >> + ret = mmc_regulator_set_vqmmc(mmc, &ios); > >> + if (ret < 0) { > >> + dev_err(mmc_dev(mmc), "%s: vqmmc set volgate failed: %d\n", > >> + mmc_hostname(mmc), ret); > >> + goto out; > >> + } > >> + } > >> + ret = regulator_enable(mmc->supply.vqmmc); > >> + } else { > >> + ret = regulator_disable(mmc->supply.vqmmc); > >> + } > >> + > >> + if (ret) > >> + dev_err(mmc_dev(mmc), "%s: vqmm %sable failed: %d\n", > >> + mmc_hostname(mmc), level ? "en":"dis", ret); > >> + else > >> + msm_host->vqmmc_enabled = level; > >> +out: > >> + return ret; > >> +} > >> + > >> +static int msm_config_vqmmc_mode(struct sdhci_msm_host *msm_host, > >> + struct mmc_host *mmc, bool hpm) > >> +{ > >> + int load, ret; > >> + > >> + load = hpm ? MMC_VQMMC_MAX_LOAD_UA : 0; > >> + ret = regulator_set_load(mmc->supply.vqmmc, load); > >> + if (ret) > >> + dev_err(mmc_dev(mmc), "%s: vqmmc set load failed: %d\n", > >> + mmc_hostname(mmc), ret); > >> + return ret; > >> +} > >> + > >> +static int sdhci_msm_set_vqmmc(struct sdhci_msm_host *msm_host, > >> + struct mmc_host *mmc, bool level) > >> +{ > >> + int ret; > >> + bool always_on; > >> + > >> + if (IS_ERR(mmc->supply.vqmmc) || > > White space. > > > >> + (mmc->ios.power_mode == MMC_POWER_UNDEFINED)) > >> + return 0; > >> + /* > >> + * For eMMC don't turn off Vqmmc, Instead just configure it in LPM > >> + * and HPM modes by setting the right amonut of load. > > /s/right amonut of load/corresponding load > > > >> + */ > >> + always_on = mmc->card && mmc_card_mmc(mmc->card); > >> + > >> + if (always_on) > >> + ret = msm_config_vqmmc_mode(msm_host, mmc, level); > >> + else > >> + ret = msm_toggle_vqmmc(msm_host, mmc, level); > > I am worried that this isn't really doing what you think it does. > > always_on may not always be set for an eMMC. > > > > This is because the mmc->card doesn't get assigned until the > > initialization of the eMMC has been completed. In other words, way > > after VCC and VCCQ have been turned on and changed voltage levels. > For the very first time, i have to enable the vqmmc. > And second time on-wards I have to set load instead of turning vqmmc off > / on. > > This condition helps me in doing exactly the same. > > This gets invoked first time when mmc_power_up() is called. > Yes, by that time card won't be initialized. So this check fails and > allows to turn on the regulator instead of setting load. > > After that, this gets invoked only next time mmc_power_up/off() is called > which is during mmc_suspend/resume. I see. That assumes the initialization always works at the first attempt, so no re-try or power cycle gets done in some error/reset path. > > By this time card is initialized, it allows to set load. Okay, I get it. Thanks for clarifying. Perhaps you can add a small comment about this in the code, so we don't forget the reasons why the code looks like this. > > > > Moreover, mmc_card_mmc() is also about legacy MMC cards, not solely for eMMCs. > > Okay. But on qcom platform, we have support for only eMMC/SD/SDIO. > So this mmc_card_mmc() meets my requirements!!! Allows only eMMC not SD > & SDIO. Well, eMMC is fairly similar to MMC, from a basic functionality point of view. So, I am quite sure you can get it to work with your controller, even if it's not officially supported. > > > If you want special treatment of an eMMC, I think it's better to use > > the DT bindings Documentation/devicetree/bindings/mmc/mmc-card.txt. If > > you have such a subnode, that indicates that there is an eMMC card > > attached. That said, if you don't like the pure DT based solution, as I suggested above - at least extend mmc_card_mmc() with checking the MMC_CAP_NONREMOVABLE flag. [...] Kind regards Uffe