From patchwork Mon Nov 12 06:52:17 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Veerabhadrarao Badiganti X-Patchwork-Id: 10678219 X-Patchwork-Delegate: agross@codeaurora.org Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AA4E715A6 for ; Mon, 12 Nov 2018 06:53:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9A0EC29F1A for ; Mon, 12 Nov 2018 06:53:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8E90C29F1F; Mon, 12 Nov 2018 06:53:10 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1244C29F1A for ; Mon, 12 Nov 2018 06:53:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731965AbeKLQo5 (ORCPT ); Mon, 12 Nov 2018 11:44:57 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:52480 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731594AbeKLQo5 (ORCPT ); Mon, 12 Nov 2018 11:44:57 -0500 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 8AE1560A33; Mon, 12 Nov 2018 06:53:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1542005582; bh=PRY5HUBwEYAW3EwbKykANvP/e0Lfw7YHrfquFSBWtbc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P4SmxT3i181THb5BAHgmsSvBOqsiGvSwNHAR1LtgmELo11YxMD+DXYQe9gPm4sy9H 9s9SkRtJKD0TxMvHl8CYZvt4boSp/3qYaTmR4csOaZHgPzNuIJqjOxp7QuIaMvp7KV YRy/Gq31GeUjPs3nbPYM8eevycbEuacn0yyv8zug= Received: from vbadigan-linux.qualcomm.com (blr-c-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.19.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: vbadigan@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 66C2960866; Mon, 12 Nov 2018 06:52:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1542005581; bh=PRY5HUBwEYAW3EwbKykANvP/e0Lfw7YHrfquFSBWtbc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=np/g3IqjQaq6hZYCoyhpUK+9winmZ/5vHIrT3qzsbz1jS8TQZFcy1Z0tDMY5UZZ5w uuoJl9WnWHTiYEUHssJuSd63QGG1/I+i6gJbGWaaHwEalkLsdWLn0HfrYGtU3SXDqV EjHhrQoJE8bauArQmXwLf+DNPRoo7wDq2kdk7b/o= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 66C2960866 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=vbadigan@codeaurora.org From: Veerabhadrarao Badiganti To: adrian.hunter@intel.com, ulf.hansson@linaro.org, robh+dt@kernel.org, evgreen@chromium.org, dianders@google.com Cc: asutoshd@codeaurora.org, riteshh@codeaurora.org, stummala@codeaurora.org, sayalil@codeaurora.org, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, Veerabhadrarao Badiganti Subject: [PATCH V5 2/2] mmc: sdhci-msm: Re-initialize DLL if MCLK is gated dynamically Date: Mon, 12 Nov 2018 12:22:17 +0530 Message-Id: <1542005537-19154-3-git-send-email-vbadigan@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1542005537-19154-1-git-send-email-vbadigan@codeaurora.org> References: <1542005537-19154-1-git-send-email-vbadigan@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On few SDHCI-MSM controllers, the host controller's clock tuning circuit may go out of sync if controller clocks are gated which eventually will result in data CRC, command CRC/timeout errors. To overcome this h/w limitation, the DLL needs to be re-initialized and restored with its old settings once clocks are ungated. Signed-off-by: Veerabhadrarao Badiganti Reviewed-by: Evan Green --- drivers/mmc/host/sdhci-msm.c | 78 +++++++++++++++++++++++++++++++++++++------- 1 file changed, 67 insertions(+), 11 deletions(-) diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c index 3cc8bfe..4cac593 100644 --- a/drivers/mmc/host/sdhci-msm.c +++ b/drivers/mmc/host/sdhci-msm.c @@ -232,6 +232,7 @@ struct sdhci_msm_variant_ops { */ struct sdhci_msm_variant_info { bool mci_removed; + bool restore_dll_config; const struct sdhci_msm_variant_ops *var_ops; const struct sdhci_msm_offset *offset; }; @@ -256,6 +257,7 @@ struct sdhci_msm_host { bool pwr_irq_flag; u32 caps_0; bool mci_removed; + bool restore_dll_config; const struct sdhci_msm_variant_ops *var_ops; const struct sdhci_msm_offset *offset; }; @@ -1025,6 +1027,48 @@ static int sdhci_msm_hs400_dll_calibration(struct sdhci_host *host) return ret; } +static bool sdhci_msm_is_tuning_needed(struct sdhci_host *host) +{ + struct mmc_ios *ios = &host->mmc->ios; + + /* + * Tuning is required for SDR104, HS200 and HS400 cards and + * if clock frequency is greater than 100MHz in these modes. + */ + if (host->clock <= CORE_FREQ_100MHZ || + !(ios->timing == MMC_TIMING_MMC_HS400 || + ios->timing == MMC_TIMING_MMC_HS200 || + ios->timing == MMC_TIMING_UHS_SDR104) || + ios->enhanced_strobe) + return false; + + return true; +} + +static int sdhci_msm_restore_sdr_dll_config(struct sdhci_host *host) +{ + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host); + int ret; + + /* + * SDR DLL comes into picture only for timing modes which needs + * tuning. + */ + if (!sdhci_msm_is_tuning_needed(host)) + return 0; + + /* Reset the tuning block */ + ret = msm_init_cm_dll(host); + if (ret) + return ret; + + /* Restore the tuning block */ + ret = msm_config_cm_dll_phase(host, msm_host->saved_tuning_phase); + + return ret; +} + static int sdhci_msm_execute_tuning(struct mmc_host *mmc, u32 opcode) { struct sdhci_host *host = mmc_priv(mmc); @@ -1035,14 +1079,7 @@ static int sdhci_msm_execute_tuning(struct mmc_host *mmc, u32 opcode) struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host); - /* - * Tuning is required for SDR104, HS200 and HS400 cards and - * if clock frequency is greater than 100MHz in these modes. - */ - if (host->clock <= CORE_FREQ_100MHZ || - !(ios.timing == MMC_TIMING_MMC_HS400 || - ios.timing == MMC_TIMING_MMC_HS200 || - ios.timing == MMC_TIMING_UHS_SDR104)) + if (!sdhci_msm_is_tuning_needed(host)) return 0; /* @@ -1069,7 +1106,6 @@ static int sdhci_msm_execute_tuning(struct mmc_host *mmc, u32 opcode) if (rc) return rc; - msm_host->saved_tuning_phase = phase; rc = mmc_send_tuning(mmc, opcode, NULL); if (!rc) { /* Tuning is successful at this tuning point */ @@ -1094,6 +1130,7 @@ static int sdhci_msm_execute_tuning(struct mmc_host *mmc, u32 opcode) rc = msm_config_cm_dll_phase(host, phase); if (rc) return rc; + msm_host->saved_tuning_phase = phase; dev_dbg(mmc_dev(mmc), "%s: Setting the tuning phase to %d\n", mmc_hostname(mmc), phase); } else { @@ -1616,7 +1653,6 @@ static void sdhci_msm_set_regulator_caps(struct sdhci_msm_host *msm_host) }; static const struct sdhci_msm_variant_info sdhci_msm_mci_var = { - .mci_removed = false, .var_ops = &mci_var_ops, .offset = &sdhci_msm_mci_offset, }; @@ -1627,9 +1663,17 @@ static void sdhci_msm_set_regulator_caps(struct sdhci_msm_host *msm_host) .offset = &sdhci_msm_v5_offset, }; +static const struct sdhci_msm_variant_info sdm845_sdhci_var = { + .mci_removed = true, + .restore_dll_config = true, + .var_ops = &v5_var_ops, + .offset = &sdhci_msm_v5_offset, +}; + static const struct of_device_id sdhci_msm_dt_match[] = { {.compatible = "qcom,sdhci-msm-v4", .data = &sdhci_msm_mci_var}, {.compatible = "qcom,sdhci-msm-v5", .data = &sdhci_msm_v5_var}, + {.compatible = "qcom,sdm845-sdhci", .data = &sdm845_sdhci_var}, {}, }; @@ -1689,6 +1733,7 @@ static int sdhci_msm_probe(struct platform_device *pdev) var_info = of_device_get_match_data(&pdev->dev); msm_host->mci_removed = var_info->mci_removed; + msm_host->restore_dll_config = var_info->restore_dll_config; msm_host->var_ops = var_info->var_ops; msm_host->offset = var_info->offset; @@ -1928,9 +1973,20 @@ static int sdhci_msm_runtime_resume(struct device *dev) struct sdhci_host *host = dev_get_drvdata(dev); struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host); + int ret; - return clk_bulk_prepare_enable(ARRAY_SIZE(msm_host->bulk_clks), + ret = clk_bulk_prepare_enable(ARRAY_SIZE(msm_host->bulk_clks), msm_host->bulk_clks); + if (ret) + return ret; + /* + * Whenever core-clock is gated dynamically, it's needed to + * restore the SDR DLL settings when the clock is ungated. + */ + if (msm_host->restore_dll_config && msm_host->clk_rate) + return sdhci_msm_restore_sdr_dll_config(host); + + return 0; } #endif