[RFC,4/7] mmc: core: add support for devfreq suspend/resume

Message ID	1531475583-7050-5-git-send-email-sayalil@codeaurora.org (mailing list archive)
State	Not Applicable, archived
Delegated to:	Andy Gross
Headers	show Return-Path: <linux-arm-msm-owner@kernel.org> sender: sayalil@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id B72E460541; Fri, 13 Jul 2018 09:53:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org B72E460541 From: Sayali Lokhande <sayalil@codeaurora.org> To: adrian.hunter@intel.com, ulf.hansson@linaro.org, robh+dt@kernel.org, mark.rutland@arm.com Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, shawn.lin@rock-chips.com, linux-arm-msm@vger.kernel.org, georgi.djakov@linaro.org, devicetree@vger.kernel.org, asutoshd@codeaurora.org, stummala@codeaurora.org, venkatg@codeaurora.org, vviswana@codeaurora.org, bjorn.andersson@linaro.org, riteshh@codeaurora.org, vbadigan@codeaurora.org, sayalil@codeaurora.org, Talel Shenhar <tatias@codeaurora.org>, Subhash Jadavani <subhashj@codeaurora.org> Subject: [PATCH RFC 4/7] mmc: core: add support for devfreq suspend/resume Date: Fri, 13 Jul 2018 15:23:00 +0530 Message-Id: <1531475583-7050-5-git-send-email-sayalil@codeaurora.org> In-Reply-To: <1531475583-7050-1-git-send-email-sayalil@codeaurora.org> References: <1531475583-7050-1-git-send-email-sayalil@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 0eaee42..49103cf 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -618,6 +618,111 @@ int mmc_init_clk_scaling(struct mmc_host *host) EXPORT_SYMBOL(mmc_init_clk_scaling); /** + * mmc_suspend_clk_scaling() - suspend clock scaling + * @host: pointer to mmc host structure + * + * This API will suspend devfreq feature for the specific host. + * The statistics collected by mmc will be cleared. + * This function is intended to be called by the pm callbacks + * (e.g. runtime_suspend, suspend) of the mmc device + */ +int mmc_suspend_clk_scaling(struct mmc_host *host) +{ + int err; + + if (!host) { + WARN(1, "bad host parameter\n"); + return -EINVAL; + } + + if (!mmc_can_scale_clk(host) || !host->clk_scaling.enable) + return 0; + + if (!host->clk_scaling.devfreq) { + pr_err("%s: %s: no devfreq is assosiated with this device\n", + mmc_hostname(host), __func__); + return -EPERM; + } + + atomic_inc(&host->clk_scaling.devfreq_abort); + wake_up(&host->wq); + err = devfreq_suspend_device(host->clk_scaling.devfreq); + if (err) { + pr_err("%s: %s: failed to suspend devfreq\n", + mmc_hostname(host), __func__); + return err; + } + host->clk_scaling.enable = false; + + host->clk_scaling.total_busy_time_us = 0; + + pr_debug("%s: devfreq was removed\n", mmc_hostname(host)); + + return 0; +} +EXPORT_SYMBOL(mmc_suspend_clk_scaling); + +/** + * mmc_resume_clk_scaling() - resume clock scaling + * @host: pointer to mmc host structure + * + * This API will resume devfreq feature for the specific host. + * This API is intended to be called by the pm callbacks + * (e.g. runtime_suspend, suspend) of the mmc device + */ +int mmc_resume_clk_scaling(struct mmc_host *host) +{ + int err = 0; + u32 max_clk_idx = 0; + u32 devfreq_max_clk = 0; + u32 devfreq_min_clk = 0; + + if (!host) { + WARN(1, "bad host parameter\n"); + return -EINVAL; + } + + if (!mmc_can_scale_clk(host)) + return 0; + + /* + * If clock scaling is already exited when resume is called, like + * during mmc shutdown, it is not an error and should not fail the + * API calling this. + */ + if (!host->clk_scaling.devfreq) { + pr_warn("%s: %s: no devfreq is assosiated with this device\n", + mmc_hostname(host), __func__); + return 0; + } + + atomic_set(&host->clk_scaling.devfreq_abort, 0); + + max_clk_idx = host->clk_scaling.freq_table_sz - 1; + devfreq_max_clk = host->clk_scaling.freq_table[max_clk_idx]; + devfreq_min_clk = host->clk_scaling.freq_table[0]; + + host->clk_scaling.curr_freq = devfreq_max_clk; + if (host->ios.clock < host->clk_scaling.freq_table[max_clk_idx]) + host->clk_scaling.curr_freq = devfreq_min_clk; + + host->clk_scaling.clk_scaling_in_progress = false; + host->clk_scaling.need_freq_change = false; + + err = devfreq_resume_device(host->clk_scaling.devfreq); + if (err) { + pr_err("%s: %s: failed to resume devfreq (%d)\n", + mmc_hostname(host), __func__, err); + } else { + host->clk_scaling.enable = true; + pr_debug("%s: devfreq resumed\n", mmc_hostname(host)); + } + + return err; +} +EXPORT_SYMBOL(mmc_resume_clk_scaling); + +/** * mmc_exit_devfreq_clk_scaling() - Disable clock scaling * @host: pointer to mmc host structure * @@ -642,6 +747,13 @@ int mmc_exit_clk_scaling(struct mmc_host *host) return -EPERM; } + err = mmc_suspend_clk_scaling(host); + if (err) { + pr_err("%s: %s: fail to suspend clock scaling (%d)\n", + mmc_hostname(host), __func__, err); + return err; + } + err = devfreq_remove_device(host->clk_scaling.devfreq); if (err) { pr_err("%s: remove devfreq failed (%d)\n", diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h index fc0a9b7..249c20d 100644 --- a/drivers/mmc/core/core.h +++ b/drivers/mmc/core/core.h @@ -97,6 +97,8 @@ static inline void mmc_delay(unsigned int ms) extern bool mmc_can_scale_clk(struct mmc_host *host); extern int mmc_init_clk_scaling(struct mmc_host *host); extern int mmc_exit_clk_scaling(struct mmc_host *host); +extern int mmc_suspend_clk_scaling(struct mmc_host *host); +extern int mmc_resume_clk_scaling(struct mmc_host *host); int mmc_execute_tuning(struct mmc_card *card); int mmc_hs200_to_hs400(struct mmc_card *card); diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 0504610..c3a71a5 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -442,15 +442,19 @@ static ssize_t store_enable(struct device *dev, mmc_get_card(host->card, NULL); if (!value) { - /* mask host capability */ + /* Suspend the clock scaling and mask host capability */ + if (host->clk_scaling.enable) + mmc_suspend_clk_scaling(host); host->caps2 &= ~MMC_CAP2_CLK_SCALE; host->clk_scaling.state = MMC_LOAD_HIGH; /* Set to max. frequency when disabling */ mmc_clk_update_freq(host, host->card->clk_scaling_highest, host->clk_scaling.state); } else if (value) { - /* Unmask host capability*/ + /* Unmask host capability and resume scaling */ host->caps2 |= MMC_CAP2_CLK_SCALE; + if (!host->clk_scaling.enable) + mmc_resume_clk_scaling(host); } mmc_put_card(host->card, NULL); diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index c8aedf3..1d286af 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -2161,6 +2161,13 @@ static int _mmc_suspend(struct mmc_host *host, bool is_suspend) unsigned int notify_type = is_suspend ? EXT_CSD_POWER_OFF_SHORT : EXT_CSD_POWER_OFF_LONG; + err = mmc_suspend_clk_scaling(host); + if (err) { + pr_err("%s: %s: fail to suspend clock scaling (%d)\n", + mmc_hostname(host), __func__, err); + return err; + } + mmc_claim_host(host); if (mmc_card_suspended(host->card)) @@ -2190,6 +2197,8 @@ static int _mmc_suspend(struct mmc_host *host, bool is_suspend) } out: mmc_release_host(host); + if (err) + mmc_resume_clk_scaling(host); return err; } @@ -2228,6 +2237,10 @@ static int _mmc_resume(struct mmc_host *host) out: mmc_release_host(host); + err = mmc_resume_clk_scaling(host); + if (err) + pr_err("%s: %s: fail to resume clock scaling (%d)\n", + mmc_hostname(host), __func__, err); return err; } @@ -2335,6 +2348,15 @@ static int _mmc_hw_reset(struct mmc_host *host) mmc_pwrseq_reset(host); } + /* Suspend clk scaling to avoid switching frequencies intermittently */ + + ret = mmc_suspend_clk_scaling(host); + if (ret) { + pr_err("%s: %s: fail to suspend clock scaling (%d)\n", + mmc_hostname(host), __func__, ret); + return ret; + } + ret = mmc_init_card(host, card->ocr, card); if (ret) { pr_err("%s: %s: mmc_init_card failed (%d)\n", @@ -2342,6 +2364,11 @@ static int _mmc_hw_reset(struct mmc_host *host) return ret; } + ret = mmc_resume_clk_scaling(host); + if (ret) + pr_err("%s: %s: fail to resume clock scaling (%d)\n", + mmc_hostname(host), __func__, ret); + return ret; } diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index 40144c1..5ae2916 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -1131,6 +1131,13 @@ static int _mmc_sd_suspend(struct mmc_host *host) { int err = 0; + err = mmc_suspend_clk_scaling(host); + if (err) { + pr_err("%s: %s: fail to suspend clock scaling (%d)\n", + mmc_hostname(host), __func__, err); + return err; + } + mmc_claim_host(host); if (mmc_card_suspended(host->card)) @@ -1182,6 +1189,12 @@ static int _mmc_sd_resume(struct mmc_host *host) err = mmc_sd_init_card(host, host->card->ocr, host->card); mmc_card_clr_suspended(host->card); + err = mmc_resume_clk_scaling(host); + if (err) { + pr_err("%s: %s: fail to resume clock scaling (%d)\n", + mmc_hostname(host), __func__, err); + goto out; + } out: mmc_release_host(host); return err;

[RFC,4/7] mmc: core: add support for devfreq suspend/resume

Commit Message

Patch