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=-8.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 88470C43441 for ; Mon, 12 Nov 2018 05:59:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EF0CB21722 for ; Mon, 12 Nov 2018 05:59:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="AbZPsiXK"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="IDUc/lik" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EF0CB21722 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731523AbeKLPvU (ORCPT ); Mon, 12 Nov 2018 10:51:20 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:49748 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728269AbeKLPvU (ORCPT ); Mon, 12 Nov 2018 10:51:20 -0500 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 1956D60A9B; Mon, 12 Nov 2018 05:59:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1542002377; bh=PRY5HUBwEYAW3EwbKykANvP/e0Lfw7YHrfquFSBWtbc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AbZPsiXK7w+8CqpHzsRCoFg4nK4Bo2XrlP75CPU58tBSjCU/MHCqvKmHL9kc4H7IL 3+EPOpprQTFouv15PCyliJdM46xEFGN1PqFVndHEmrU/jd1olY2B/3oCP9u3q1bexW LzItYVv12w4BpD6jnjCdk6+jBriCVvGJCxOkfjLc= 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 D7EF660600; Mon, 12 Nov 2018 05:59:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1542002375; bh=PRY5HUBwEYAW3EwbKykANvP/e0Lfw7YHrfquFSBWtbc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IDUc/likZjdwSkSTTcq0O6jRxGFKb9WINcYx6g15zo0RXlMUJC5ReARQOWJZJt5qq 8rF3zAVHadN8xxdea6YTvcN6o7X19HgKjr/SakvkHIktcfJ4dfLLM25CH1ds+pk4TS dz6NX6NTw9pvFf/0D+zKCUy8biKWx0GYKd912kd4= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org D7EF660600 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, Veerabhadrarao Badiganti , linux-kernel@vger.kernel.org (open list) Subject: [PATCH V4 2/2] mmc: sdhci-msm: Re-initialize DLL if MCLK is gated dynamically Date: Mon, 12 Nov 2018 11:26:49 +0530 Message-Id: <1542002209-1510-3-git-send-email-vbadigan@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1542002209-1510-1-git-send-email-vbadigan@codeaurora.org> References: <1542002209-1510-1-git-send-email-vbadigan@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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 -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.