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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham 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 7B1A8C71156 for ; Thu, 26 Nov 2020 08:16:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4DAF820872 for ; Thu, 26 Nov 2020 08:16:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388767AbgKZIQj (ORCPT ); Thu, 26 Nov 2020 03:16:39 -0500 Received: from mga07.intel.com ([134.134.136.100]:49317 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388754AbgKZIQj (ORCPT ); Thu, 26 Nov 2020 03:16:39 -0500 IronPort-SDR: m31vHCa+XY+sE+vSmV5UPLh542cBkoubW2NPcbpGENopF4nqF0bB0D01ei/2RzV7mhW7ADVxsf C/uIj4n1GP1w== X-IronPort-AV: E=McAfee;i="6000,8403,9816"; a="236384688" X-IronPort-AV: E=Sophos;i="5.78,371,1599548400"; d="scan'208";a="236384688" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Nov 2020 00:16:38 -0800 IronPort-SDR: 92+5kxHRm22J1QxOhD/8PW1RRFDhiEPGtj8A4bQ32ZCwq+GOd06C173cn0q2f1uR/fKlmwJc6C /2FZZO4BSBfA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.78,371,1599548400"; d="scan'208";a="362721502" Received: from ahunter-desktop.fi.intel.com (HELO [10.237.72.94]) ([10.237.72.94]) by fmsmga004.fm.intel.com with ESMTP; 26 Nov 2020 00:16:33 -0800 From: Adrian Hunter Subject: Re: [RFC PATCH v3.1 12/27] mmc: sdhci-uhs2: add reset function To: AKASHI Takahiro , ulf.hansson@linaro.org Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, ben.chuang@genesyslogic.com.tw, greg.tu@genesyslogic.com.tw References: <20201106022726.19831-1-takahiro.akashi@linaro.org> <20201106022726.19831-13-takahiro.akashi@linaro.org> Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: Date: Thu, 26 Nov 2020 10:16:11 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <20201106022726.19831-13-takahiro.akashi@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/11/20 4:27 am, AKASHI Takahiro wrote: > Sdhci_uhs2_reset() does a UHS-II specific reset operation. > > Signed-off-by: Ben Chuang > Signed-off-by: AKASHI Takahiro > --- > drivers/mmc/host/sdhci-uhs2.c | 49 +++++++++++++++++++++++++++++++++++ > drivers/mmc/host/sdhci-uhs2.h | 1 + > drivers/mmc/host/sdhci.c | 3 ++- > drivers/mmc/host/sdhci.h | 1 + > 4 files changed, 53 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c > index 08905ed081fb..e2b9743fe17d 100644 > --- a/drivers/mmc/host/sdhci-uhs2.c > +++ b/drivers/mmc/host/sdhci-uhs2.c > @@ -10,6 +10,7 @@ > * Author: AKASHI Takahiro > */ > > +#include > #include > > #include "sdhci.h" > @@ -49,6 +50,54 @@ void sdhci_uhs2_dump_regs(struct sdhci_host *host) > } > EXPORT_SYMBOL_GPL(sdhci_uhs2_dump_regs); > > +/*****************************************************************************\ > + * * > + * Low level functions * > + * * > +\*****************************************************************************/ > + > +/** > + * sdhci_uhs2_reset - invoke SW reset > + * @host: SDHCI host > + * @mask: Control mask > + * > + * Invoke SW reset, depending on a bit in @mask and wait for completion. > + */ > +void sdhci_uhs2_reset(struct sdhci_host *host, u16 mask) > +{ > + unsigned long timeout; > + > + if (!(host->mmc->caps & MMC_CAP_UHS2)) Please make a helper so this can be like: if (!sdhci_uhs2_mode(host)) The capability will be always present for hosts that support UHS2, but not all cards support UHS2 mode. I suggest just adding a bool to struct sdhci_host to keep track of when the host is in UHS2 mode. > + return; > + > + sdhci_writew(host, mask, SDHCI_UHS2_SW_RESET); > + > + if (mask & SDHCI_UHS2_SW_RESET_FULL) { > + host->clock = 0; > + /* Reset-all turns off SD Bus Power */ > + if (host->quirks2 & SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON) I would prefer not to support any legacy quirks that we do not need right now. Just be sure to add a comment somewhere listing which quirks are not supported for UHS2 host controllers. > + sdhci_runtime_pm_bus_off(host); > + } > + > + /* Wait max 100 ms */ > + timeout = 10000; > + > + /* hw clears the bit when it's done */ > + while (sdhci_readw(host, SDHCI_UHS2_SW_RESET) & mask) { This kind of loop can now be done with read_poll_timeout_atomic(sdhci_readw, ..., host, SDHCI_UHS2_SW_RESET) > + if (timeout == 0) { > + pr_err("%s: %s: Reset 0x%x never completed.\n", > + __func__, mmc_hostname(host->mmc), (int)mask); > + pr_err("%s: clean reset bit\n", > + mmc_hostname(host->mmc)); > + sdhci_writeb(host, 0, SDHCI_UHS2_SW_RESET); > + return; > + } > + timeout--; > + udelay(10); > + } > +} > +EXPORT_SYMBOL_GPL(sdhci_uhs2_reset); > + > /*****************************************************************************\ > * * > * Driver init/exit * > diff --git a/drivers/mmc/host/sdhci-uhs2.h b/drivers/mmc/host/sdhci-uhs2.h > index b9529d32b58d..7bb7a0d67109 100644 > --- a/drivers/mmc/host/sdhci-uhs2.h > +++ b/drivers/mmc/host/sdhci-uhs2.h > @@ -210,5 +210,6 @@ > struct sdhci_host; > > void sdhci_uhs2_dump_regs(struct sdhci_host *host); > +void sdhci_uhs2_reset(struct sdhci_host *host, u16 mask); > > #endif /* __SDHCI_UHS2_H */ > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index d4a57e8c9bb8..af336bdb4305 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -195,13 +195,14 @@ static void sdhci_runtime_pm_bus_on(struct sdhci_host *host) > pm_runtime_get_noresume(host->mmc->parent); > } > > -static void sdhci_runtime_pm_bus_off(struct sdhci_host *host) > +void sdhci_runtime_pm_bus_off(struct sdhci_host *host) > { > if (!host->bus_on) > return; > host->bus_on = false; > pm_runtime_put_noidle(host->mmc->parent); > } > +EXPORT_SYMBOL_GPL(sdhci_runtime_pm_bus_off); > > void sdhci_reset(struct sdhci_host *host, u8 mask) > { > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h > index d9d7a76cedc1..b9932423db08 100644 > --- a/drivers/mmc/host/sdhci.h > +++ b/drivers/mmc/host/sdhci.h > @@ -831,6 +831,7 @@ static inline void sdhci_read_caps(struct sdhci_host *host) > __sdhci_read_caps(host, NULL, NULL, NULL); > } > > +void sdhci_runtime_pm_bus_off(struct sdhci_host *host); > u16 sdhci_calc_clk(struct sdhci_host *host, unsigned int clock, > unsigned int *actual_clock); > void sdhci_set_clock(struct sdhci_host *host, unsigned int clock); >