From patchwork Mon Oct 21 14:29:33 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ram Prakash Gupta X-Patchwork-Id: 11202371 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4F918913 for ; Mon, 21 Oct 2019 14:37:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 11E5F2084C for ; Mon, 21 Oct 2019 14:37:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729311AbfJUOg4 (ORCPT ); Mon, 21 Oct 2019 10:36:56 -0400 Received: from alexa-out-blr-02.qualcomm.com ([103.229.18.198]:28994 "EHLO alexa-out-blr-02.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726987AbfJUOgy (ORCPT ); Mon, 21 Oct 2019 10:36:54 -0400 Received: from ironmsg02-blr.qualcomm.com ([10.86.208.131]) by alexa-out-blr-02.qualcomm.com with ESMTP/TLS/AES256-SHA; 21 Oct 2019 20:00:39 +0530 IronPort-SDR: a0Ii4OYeCg1O82cvaraOx7VVZLZNJjNpj6tMf/C1Qj81j2XPQH8IHQNzMCd1wuBjtXvDt6JbEw 9y6y2Z8A2H+mJAUbAb5RPd7f37WVzy9ivjMHjqfyNQkmEafiuYp8mtNA66peMLB4q7NCHjGh0y GX3QqFIcpu53679R1E++NiuAahKCuiE+6CMNpmTQkiEyJfnhfjLOGa+ytF8/bb9IbmZgV2hELS PjXk124BPxdQNJL7BaDVvhfY4Q5EHp0JCOnO6LbKowEFvhh+M+RKkcWlctYO42n1ewLIjSLKk8 HiRJ2PjXmAtg4UHp1lP25a8D Received: from rampraka-linux.qualcomm.com ([10.206.25.221]) by ironmsg02-blr.qualcomm.com with ESMTP; 21 Oct 2019 20:00:39 +0530 Received: by rampraka-linux.qualcomm.com (Postfix, from userid 2305851) id CA4D6329D; Mon, 21 Oct 2019 20:00:37 +0530 (IST) From: Ram Prakash Gupta To: asutoshd@codeaurora.org, stummala@codeaurora.org, sayalil@codeaurora.org, rampraka@codeaurora.org, vbadigan@codeaurora.org, cang@codeaurora.org, ppvk@codeaurora.org, adrian.hunter@intel.com, ulf.hansson@linaro.org, robh+dt@kernel.org, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Cc: Sujit Reddy Thumma , Talel Shenhar , Ritesh Harjani , "Bao D. Nguyen" Subject: [RFC 2/6] mmc: core: Add core scaling support in driver Date: Mon, 21 Oct 2019 19:59:33 +0530 Message-Id: <1571668177-3766-3-git-send-email-rampraka@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1571668177-3766-1-git-send-email-rampraka@codeaurora.org> References: <1571668177-3766-1-git-send-email-rampraka@codeaurora.org> Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org Adding clock scaling support in clock scaling driver. Signed-off-by: Sujit Reddy Thumma Signed-off-by: Talel Shenhar Signed-off-by: Sahitya Tummala Signed-off-by: Asutosh Das Signed-off-by: Ritesh Harjani Signed-off-by: Veerabhadrarao Badiganti Signed-off-by: Bao D. Nguyen Signed-off-by: Can Guo Signed-off-by: Sayali Lokhande Co-Developed-by: Ram Prakash Gupta Signed-off-by: Ram Prakash Gupta --- drivers/mmc/core/core.c | 769 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/mmc/core/core.h | 17 ++ drivers/mmc/core/mmc.c | 192 ++++++++++++ drivers/mmc/core/sd.c | 54 ++++ 4 files changed, 1032 insertions(+) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 2211273..f0c233c 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -39,6 +40,7 @@ #include "card.h" #include "bus.h" #include "host.h" +#include "queue.h" #include "sdio_bus.h" #include "pwrseq.h" @@ -109,6 +111,773 @@ static inline void mmc_should_fail_request(struct mmc_host *host, #endif /* CONFIG_FAIL_MMC_REQUEST */ +static bool mmc_is_data_request(struct mmc_request *mmc_request) +{ + switch (mmc_request->cmd->opcode) { + case MMC_READ_SINGLE_BLOCK: + case MMC_READ_MULTIPLE_BLOCK: + case MMC_WRITE_BLOCK: + case MMC_WRITE_MULTIPLE_BLOCK: + return true; + default: + return false; + } +} + +static void mmc_clk_scaling_start_busy(struct mmc_host *host, bool lock_needed) +{ + struct mmc_devfeq_clk_scaling *clk_scaling = &host->clk_scaling; + + if (!clk_scaling->enable) + return; + + if (lock_needed) + spin_lock_bh(&clk_scaling->lock); + + clk_scaling->start_busy = ktime_get(); + clk_scaling->is_busy_started = true; + + if (lock_needed) + spin_unlock_bh(&clk_scaling->lock); +} + +static void mmc_clk_scaling_stop_busy(struct mmc_host *host, bool lock_needed) +{ + struct mmc_devfeq_clk_scaling *clk_scaling = &host->clk_scaling; + + if (!clk_scaling->enable) + return; + + if (lock_needed) + spin_lock_bh(&clk_scaling->lock); + + if (!clk_scaling->is_busy_started) { + WARN_ON(1); + goto out; + } + + clk_scaling->total_busy_time_us += + ktime_to_us(ktime_sub(ktime_get(), + clk_scaling->start_busy)); + pr_debug("%s: accumulated busy time is %lu usec\n", + mmc_hostname(host), clk_scaling->total_busy_time_us); + clk_scaling->is_busy_started = false; + +out: + if (lock_needed) + spin_unlock_bh(&clk_scaling->lock); +} + +/* mmc_cqe_clk_scaling_start_busy() - start busy timer for data requests + * @host: pointer to mmc host structure + * @lock_needed: flag indication if locking is needed + * + * This function starts the busy timer in case it was not already started. + */ +void mmc_cqe_clk_scaling_start_busy(struct mmc_queue *mq, + struct mmc_host *host, bool lock_needed) +{ + unsigned long flags; + + if (!host->clk_scaling.enable) + return; + + if (lock_needed) + spin_lock_irqsave(&host->clk_scaling.lock, flags); + + if (!host->clk_scaling.is_busy_started && + !(mq->cqe_busy & MMC_CQE_DCMD_BUSY)) { + host->clk_scaling.start_busy = ktime_get(); + host->clk_scaling.is_busy_started = true; + } + + if (lock_needed) + spin_unlock_irqrestore(&host->clk_scaling.lock, flags); +} +EXPORT_SYMBOL(mmc_cqe_clk_scaling_start_busy); + +/** + * mmc_cqe_clk_scaling_stop_busy() - stop busy timer for last data requests + * @host: pointer to mmc host structure + * @lock_needed: flag indication if locking is needed + * + * This function stops the busy timer in case it is the last data request. + * In case the current request is not the last one, the busy time till + * now will be accumulated and the counter will be restarted. + */ +void mmc_cqe_clk_scaling_stop_busy(struct mmc_host *host, + bool lock_needed, bool is_cqe_dcmd) +{ + unsigned int cqe_active_reqs = 0; + + if (!host->clk_scaling.enable) + return; + + cqe_active_reqs = atomic_read(&host->active_reqs); + + /* + * This gets invoked from CQE completion path which is hard IRQ context + * So use spin_lock() instread of spin_lock_irqsave() + */ + if (lock_needed) + spin_lock(&host->clk_scaling.lock); + + /* + * For CQ mode: In completion of DCMD request, start busy time in + * case of pending data requests + */ + if (is_cqe_dcmd) { + if (cqe_active_reqs && !host->clk_scaling.is_busy_started) { + host->clk_scaling.is_busy_started = true; + host->clk_scaling.start_busy = ktime_get(); + } + goto out; + } + + host->clk_scaling.total_busy_time_us += + ktime_to_us(ktime_sub(ktime_get(), + host->clk_scaling.start_busy)); + + if (cqe_active_reqs) { + host->clk_scaling.is_busy_started = true; + host->clk_scaling.start_busy = ktime_get(); + } else { + host->clk_scaling.is_busy_started = false; + } +out: + if (lock_needed) + spin_unlock(&host->clk_scaling.lock); + +} +EXPORT_SYMBOL(mmc_cqe_clk_scaling_stop_busy); + +/** + * mmc_can_scale_clk() - Check clock scaling capability + * @host: pointer to mmc host structure + */ +bool mmc_can_scale_clk(struct mmc_host *host) +{ + if (!host) { + pr_err("bad host parameter\n"); + WARN_ON(1); + return false; + } + + return host->caps2 & MMC_CAP2_CLK_SCALE; +} +EXPORT_SYMBOL(mmc_can_scale_clk); + +static int mmc_devfreq_get_dev_status(struct device *dev, + struct devfreq_dev_status *status) +{ + struct mmc_host *host = container_of(dev, struct mmc_host, class_dev); + struct mmc_devfeq_clk_scaling *clk_scaling; + unsigned long flags; + + if (!host) { + pr_err("bad host parameter\n"); + WARN_ON(1); + return -EINVAL; + } + + clk_scaling = &host->clk_scaling; + + if (!clk_scaling->enable) + return 0; + + spin_lock_irqsave(&host->clk_scaling.lock, flags); + + /* accumulate the busy time of ongoing work */ + memset(status, 0, sizeof(*status)); + if (clk_scaling->is_busy_started) { + if (host->cqe_on) { + /* the "busy-timer" will be restarted in case there + * are pending data requests + */ + mmc_cqe_clk_scaling_stop_busy(host, false, false); + } else { + mmc_clk_scaling_stop_busy(host, false); + mmc_clk_scaling_start_busy(host, false); + } + } + + status->busy_time = clk_scaling->total_busy_time_us; + status->total_time = ktime_to_us(ktime_sub(ktime_get(), + clk_scaling->measure_interval_start)); + clk_scaling->total_busy_time_us = 0; + status->current_frequency = clk_scaling->curr_freq; + clk_scaling->measure_interval_start = ktime_get(); + + pr_debug("%s: status: load = %lu%% - total_time=%lu busy_time = %lu, clk=%lu\n", + mmc_hostname(host), + (status->busy_time*100)/status->total_time, + status->total_time, status->busy_time, + status->current_frequency); + + spin_unlock_irqrestore(&host->clk_scaling.lock, flags); + + return 0; +} + +static bool mmc_is_valid_state_for_clk_scaling(struct mmc_host *host) +{ + struct mmc_card *card = host->card; + u32 status; + + /* + * If the current partition type is RPMB, clock switching may not + * work properly as sending tuning command (CMD21) is illegal in + * this mode. + */ + if (!card || (mmc_card_mmc(card) && + (card->part_curr == EXT_CSD_PART_CONFIG_ACC_RPMB))) + return false; + + if (mmc_send_status(card, &status)) { + pr_err("%s: Get card status fail\n", mmc_hostname(card->host)); + return false; + } + + return R1_CURRENT_STATE(status) == R1_STATE_TRAN; +} + +int mmc_clk_update_freq(struct mmc_host *host, + unsigned long freq, enum mmc_load state) +{ + int err = 0; + + if (!host) { + pr_err("bad host parameter\n"); + WARN_ON(1); + return -EINVAL; + } + + /* make sure the card supports the frequency we want */ + if (unlikely(freq > host->card->clk_scaling_highest)) { + freq = host->card->clk_scaling_highest; + pr_warn("%s: %s: High freq was overridden to %lu\n", + mmc_hostname(host), __func__, + host->card->clk_scaling_highest); + } + + if (unlikely(freq < host->card->clk_scaling_lowest)) { + freq = host->card->clk_scaling_lowest; + pr_warn("%s: %s: Low freq was overridden to %lu\n", + mmc_hostname(host), __func__, + host->card->clk_scaling_lowest); + } + + if (freq == host->clk_scaling.curr_freq) + goto out; + + if (host->cqe_on) { + err = host->cqe_ops->cqe_wait_for_idle(host); + if (err) { + pr_err("%s: %s: CQE went in recovery path\n", + mmc_hostname(host), __func__); + goto out; + } + host->cqe_ops->cqe_off(host); + } + + if (!mmc_is_valid_state_for_clk_scaling(host)) { + pr_debug("%s: invalid state for clock scaling - skipping\n", + mmc_hostname(host)); + goto out; + } + + err = host->bus_ops->change_bus_speed(host, &freq); + if (!err) + host->clk_scaling.curr_freq = freq; + else + pr_err("%s: %s: failed (%d) at freq=%lu\n", + mmc_hostname(host), __func__, err, freq); + + /* + * CQE would be enabled as part of CQE issueing path + * So no need to unhalt it explicitly + */ + +out: + return err; +} +EXPORT_SYMBOL(mmc_clk_update_freq); + +static int mmc_devfreq_set_target(struct device *dev, + unsigned long *freq, u32 devfreq_flags) +{ + struct mmc_host *host = container_of(dev, struct mmc_host, class_dev); + struct mmc_devfeq_clk_scaling *clk_scaling; + int err = 0; + int abort; + unsigned long pflags = current->flags; + unsigned long flags; + + /* Ensure scaling would happen even in memory pressure conditions */ + current->flags |= PF_MEMALLOC; + + if (!(host && freq)) { + pr_err("%s: unexpected host/freq parameter\n", __func__); + err = -EINVAL; + goto out; + } + + clk_scaling = &host->clk_scaling; + + if (!clk_scaling->enable) + goto out; + + pr_debug("%s: target freq = %lu (%s)\n", mmc_hostname(host), + *freq, current->comm); + + spin_lock_irqsave(&clk_scaling->lock, flags); + if (clk_scaling->target_freq == *freq || + clk_scaling->skip_clk_scale_freq_update) { + spin_unlock_irqrestore(&clk_scaling->lock, flags); + goto out; + } + + clk_scaling->need_freq_change = true; + clk_scaling->target_freq = *freq; + clk_scaling->state = *freq < clk_scaling->curr_freq ? + MMC_LOAD_LOW : MMC_LOAD_HIGH; + spin_unlock_irqrestore(&clk_scaling->lock, flags); + + if (!clk_scaling->is_suspended && host->ios.clock) + abort = __mmc_claim_host(host, NULL, + &clk_scaling->devfreq_abort); + else + goto out; + + if (abort) + goto out; + + /* + * In case we were able to claim host there is no need to + * defer the frequency change. It will be done now + */ + clk_scaling->need_freq_change = false; + + err = mmc_clk_update_freq(host, *freq, clk_scaling->state); + if (err && err != -EAGAIN) + pr_err("%s: clock scale to %lu failed with error %d\n", + mmc_hostname(host), *freq, err); + else + pr_debug("%s: clock change to %lu finished successfully (%s)\n", + mmc_hostname(host), *freq, current->comm); + + mmc_release_host(host); +out: + current_restore_flags(pflags, PF_MEMALLOC); + return err; +} + +/** + * mmc_deferred_scaling() - scale clocks from data path (mmc thread context) + * @host: pointer to mmc host structure + * + * This function does clock scaling in case "need_freq_change" flag was set + * by the clock scaling logic. + */ +void mmc_deferred_scaling(struct mmc_host *host) +{ + unsigned long target_freq; + int err; + struct mmc_devfeq_clk_scaling clk_scaling; + unsigned long flags; + + if (!host->clk_scaling.enable) + return; + + spin_lock_irqsave(&host->clk_scaling.lock, flags); + + if (!host->clk_scaling.need_freq_change) { + spin_unlock_irqrestore(&host->clk_scaling.lock, flags); + return; + } + + atomic_inc(&host->clk_scaling.devfreq_abort); + target_freq = host->clk_scaling.target_freq; + /* + * Store the clock scaling state while the lock is acquired so that + * if devfreq context modifies clk_scaling, it will get reflected only + * in the next deferred scaling check. + */ + clk_scaling = host->clk_scaling; + host->clk_scaling.need_freq_change = false; + spin_unlock_irqrestore(&host->clk_scaling.lock, flags); + + pr_debug("%s: doing deferred frequency change (%lu) (%s)\n", + mmc_hostname(host), + target_freq, current->comm); + + err = mmc_clk_update_freq(host, target_freq, + clk_scaling.state); + if (err && err != -EAGAIN) + pr_err("%s: failed on deferred scale clocks (%d)\n", + mmc_hostname(host), err); + else + pr_debug("%s: clocks were successfully scaled to %lu (%s)\n", + mmc_hostname(host), + target_freq, current->comm); + atomic_dec(&host->clk_scaling.devfreq_abort); +} +EXPORT_SYMBOL(mmc_deferred_scaling); + +static int mmc_devfreq_create_freq_table(struct mmc_host *host) +{ + int i; + struct mmc_devfeq_clk_scaling *clk_scaling = &host->clk_scaling; + + pr_debug("%s: supported: lowest=%lu, highest=%lu\n", + mmc_hostname(host), + host->card->clk_scaling_lowest, + host->card->clk_scaling_highest); + + /* + * Create the frequency table and initialize it with default values. + * Initialize it with platform specific frequencies if the frequency + * table supplied by platform driver is present, otherwise initialize + * it with min and max frequencies supported by the card. + */ + if (!clk_scaling->freq_table) { + if (clk_scaling->pltfm_freq_table_sz) + clk_scaling->freq_table_sz = + clk_scaling->pltfm_freq_table_sz; + else + clk_scaling->freq_table_sz = 2; + + clk_scaling->freq_table = kcalloc( + clk_scaling->freq_table_sz, + sizeof(*(clk_scaling->freq_table)), GFP_KERNEL); + if (!clk_scaling->freq_table) + return -ENOMEM; + + if (clk_scaling->pltfm_freq_table) { + memcpy(clk_scaling->freq_table, + clk_scaling->pltfm_freq_table, + (clk_scaling->pltfm_freq_table_sz * + sizeof(*(clk_scaling->pltfm_freq_table)))); + } else { + pr_debug("%s: no frequency table defined - setting default\n", + mmc_hostname(host)); + clk_scaling->freq_table[0] = + host->card->clk_scaling_lowest; + clk_scaling->freq_table[1] = + host->card->clk_scaling_highest; + goto out; + } + } + + if (host->card->clk_scaling_lowest > + clk_scaling->freq_table[0]) + pr_debug("%s: frequency table undershot possible freq\n", + mmc_hostname(host)); + + for (i = 0; i < clk_scaling->freq_table_sz; i++) { + if (clk_scaling->freq_table[i] <= + host->card->clk_scaling_highest) + continue; + clk_scaling->freq_table[i] = + host->card->clk_scaling_highest; + clk_scaling->freq_table_sz = i + 1; + pr_debug("%s: frequency table overshot possible freq (%d)\n", + mmc_hostname(host), clk_scaling->freq_table[i]); + break; + } + +out: + /** + * devfreq requires unsigned long type freq_table while the + * freq_table in clk_scaling is un32. Here allocates an individual + * memory space for it and release it when exit clock scaling. + */ + clk_scaling->devfreq_profile.freq_table = kcalloc( + clk_scaling->freq_table_sz, + sizeof(*(clk_scaling->devfreq_profile.freq_table)), + GFP_KERNEL); + if (!clk_scaling->devfreq_profile.freq_table) { + kfree(clk_scaling->freq_table); + return -ENOMEM; + } + clk_scaling->devfreq_profile.max_state = clk_scaling->freq_table_sz; + + for (i = 0; i < clk_scaling->freq_table_sz; i++) { + clk_scaling->devfreq_profile.freq_table[i] = + clk_scaling->freq_table[i]; + pr_debug("%s: freq[%d] = %u\n", + mmc_hostname(host), i, clk_scaling->freq_table[i]); + } + + return 0; +} + +/** + * mmc_init_devfreq_clk_scaling() - Initialize clock scaling + * @host: pointer to mmc host structure + * + * Initialize clock scaling for supported hosts. It is assumed that the caller + * ensure clock is running at maximum possible frequency before calling this + * function. Shall use struct devfreq_simple_ondemand_data to configure + * governor. + */ +int mmc_init_clk_scaling(struct mmc_host *host) +{ + int err; + struct devfreq *devfreq; + + if (!host || !host->card) { + pr_err("%s: unexpected host/card parameters\n", + __func__); + return -EINVAL; + } + + if (!mmc_can_scale_clk(host) || + !host->bus_ops->change_bus_speed) { + pr_debug("%s: clock scaling is not supported\n", + mmc_hostname(host)); + return 0; + } + + pr_debug("registering %s dev (%pK) to devfreq\n", + mmc_hostname(host), + mmc_classdev(host)); + + if (host->clk_scaling.devfreq) { + pr_err("%s: dev is already registered for dev %pK\n", + mmc_hostname(host), + mmc_dev(host)); + return -EPERM; + } + spin_lock_init(&host->clk_scaling.lock); + atomic_set(&host->clk_scaling.devfreq_abort, 0); + host->clk_scaling.curr_freq = host->ios.clock; + host->clk_scaling.need_freq_change = false; + host->clk_scaling.is_busy_started = false; + + host->clk_scaling.devfreq_profile.polling_ms = + host->clk_scaling.polling_delay_ms; + host->clk_scaling.devfreq_profile.get_dev_status = + mmc_devfreq_get_dev_status; + host->clk_scaling.devfreq_profile.target = mmc_devfreq_set_target; + host->clk_scaling.devfreq_profile.initial_freq = host->ios.clock; + + host->clk_scaling.ondemand_gov_data.upthreshold = + host->clk_scaling.upthreshold; + host->clk_scaling.ondemand_gov_data.downdifferential = + host->clk_scaling.upthreshold - host->clk_scaling.downthreshold; + + err = mmc_devfreq_create_freq_table(host); + if (err) { + pr_err("%s: fail to create devfreq frequency table\n", + mmc_hostname(host)); + return err; + } + + dev_pm_opp_add(mmc_classdev(host), + host->clk_scaling.devfreq_profile.freq_table[0], 0); + dev_pm_opp_add(mmc_classdev(host), + host->clk_scaling.devfreq_profile.freq_table[1], 0); + + pr_debug("%s: adding devfreq with: upthreshold=%u downthreshold=%u polling=%u\n", + mmc_hostname(host), + host->clk_scaling.ondemand_gov_data.upthreshold, + host->clk_scaling.ondemand_gov_data.downdifferential, + host->clk_scaling.devfreq_profile.polling_ms); + + devfreq = devfreq_add_device( + mmc_classdev(host), + &host->clk_scaling.devfreq_profile, + "simple_ondemand", + &host->clk_scaling.ondemand_gov_data); + + if (IS_ERR(devfreq)) { + pr_err("%s: unable to register with devfreq\n", + mmc_hostname(host)); + dev_pm_opp_remove(mmc_classdev(host), + host->clk_scaling.devfreq_profile.freq_table[0]); + dev_pm_opp_remove(mmc_classdev(host), + host->clk_scaling.devfreq_profile.freq_table[1]); + return PTR_ERR(devfreq); + } + + host->clk_scaling.devfreq = devfreq; + pr_debug("%s: clk scaling is enabled for device %s (%pK) with devfreq %pK (clock = %uHz)\n", + mmc_hostname(host), + dev_name(mmc_classdev(host)), + mmc_classdev(host), + host->clk_scaling.devfreq, + host->ios.clock); + + host->clk_scaling.enable = true; + + return err; +} +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 || + host->clk_scaling.is_suspended) + 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.is_suspended = true; + + 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.target_freq = host->clk_scaling.curr_freq; + + 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.is_suspended = false; + 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 + * + * Disable clock scaling permanently. + */ +int mmc_exit_clk_scaling(struct mmc_host *host) +{ + int err; + + if (!host) { + pr_err("%s: bad host parameter\n", __func__); + WARN_ON(1); + return -EINVAL; + } + + if (!mmc_can_scale_clk(host)) + 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; + } + + 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", + mmc_hostname(host), err); + return err; + } + + dev_pm_opp_remove(mmc_classdev(host), + host->clk_scaling.devfreq_profile.freq_table[0]); + dev_pm_opp_remove(mmc_classdev(host), + host->clk_scaling.devfreq_profile.freq_table[1]); + + kfree(host->clk_scaling.devfreq_profile.freq_table); + + host->clk_scaling.devfreq = NULL; + atomic_set(&host->clk_scaling.devfreq_abort, 1); + + kfree(host->clk_scaling.freq_table); + host->clk_scaling.freq_table = NULL; + + pr_debug("%s: devfreq was removed\n", mmc_hostname(host)); + + return 0; +} +EXPORT_SYMBOL(mmc_exit_clk_scaling); + + static inline void mmc_complete_cmd(struct mmc_request *mrq) { if (mrq->cap_cmd_during_tfr && !completion_done(&mrq->cmd_completion)) diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h index 328c78d..2abf75a 100644 --- a/drivers/mmc/core/core.h +++ b/drivers/mmc/core/core.h @@ -14,6 +14,7 @@ struct mmc_host; struct mmc_card; struct mmc_request; +struct mmc_queue; #define MMC_CMD_RETRIES 3 @@ -29,6 +30,7 @@ struct mmc_bus_ops { int (*shutdown)(struct mmc_host *); int (*hw_reset)(struct mmc_host *); int (*sw_reset)(struct mmc_host *); + int (*change_bus_speed)(struct mmc_host *host, unsigned long *freq); }; void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops); @@ -57,6 +59,8 @@ int mmc_select_drive_strength(struct mmc_card *card, unsigned int max_dtr, void mmc_power_cycle(struct mmc_host *host, u32 ocr); void mmc_set_initial_state(struct mmc_host *host); u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max); +int mmc_clk_update_freq(struct mmc_host *host, + unsigned long freq, enum mmc_load state); static inline void mmc_delay(unsigned int ms) { @@ -87,6 +91,19 @@ static inline void mmc_delay(unsigned int ms) void mmc_add_card_debugfs(struct mmc_card *card); void mmc_remove_card_debugfs(struct mmc_card *card); +extern bool mmc_can_scale_clk(struct mmc_host *host); +extern int mmc_init_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); +extern int mmc_exit_clk_scaling(struct mmc_host *host); +extern void mmc_deferred_scaling(struct mmc_host *host); +extern void mmc_cqe_clk_scaling_start_busy(struct mmc_queue *mq, + struct mmc_host *host, bool lock_needed); +extern void mmc_cqe_clk_scaling_stop_busy(struct mmc_host *host, + bool lock_needed, bool is_cqe_dcmd); + +extern unsigned long mmc_get_max_frequency(struct mmc_host *host); + int mmc_execute_tuning(struct mmc_card *card); int mmc_hs200_to_hs400(struct mmc_card *card); int mmc_hs400_to_hs200(struct mmc_card *card); diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index c880489..c9fccfc 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -1539,6 +1539,198 @@ static int mmc_hs200_tuning(struct mmc_card *card) return mmc_execute_tuning(card); } +static int mmc_select_hs_ddr52(struct mmc_host *host) +{ + int err; + + mmc_select_hs(host->card); + err = mmc_select_bus_width(host->card); + if (err < 0) { + pr_err("%s: %s: select_bus_width failed(%d)\n", + mmc_hostname(host), __func__, err); + return err; + } + + err = mmc_select_hs_ddr(host->card); + mmc_set_clock(host, MMC_HIGH_52_MAX_DTR); + + return err; +} + +/* + * Scale down from HS400 to HS in order to allow frequency change. + * This is needed for cards that doesn't support changing frequency in HS400 + */ +static int mmc_scale_low(struct mmc_host *host, unsigned long freq) +{ + int err = 0; + + mmc_set_timing(host, MMC_TIMING_LEGACY); + mmc_set_clock(host, MMC_HIGH_26_MAX_DTR); + + if (host->clk_scaling.lower_bus_speed_mode & + MMC_SCALING_LOWER_DDR52_MODE) { + err = mmc_select_hs_ddr52(host); + if (err) + pr_err("%s: %s: failed to switch to DDR52: err: %d\n", + mmc_hostname(host), __func__, err); + else + return err; + } + + err = mmc_select_hs(host->card); + if (err) { + pr_err("%s: %s: scaling low: failed (%d)\n", + mmc_hostname(host), __func__, err); + return err; + } + + err = mmc_select_bus_width(host->card); + if (err < 0) { + pr_err("%s: %s: select_bus_width failed(%d)\n", + mmc_hostname(host), __func__, err); + return err; + } + + mmc_set_clock(host, freq); + + return 0; +} + +/* + * Scale UP from HS to HS200/H400 + */ +static int mmc_scale_high(struct mmc_host *host) +{ + int err = 0; + + if (mmc_card_ddr52(host->card)) { + mmc_set_timing(host, MMC_TIMING_LEGACY); + mmc_set_clock(host, MMC_HIGH_26_MAX_DTR); + } + + if (!host->card->ext_csd.strobe_support) { + if (!(host->card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200)) { + pr_err("%s: %s: card does not support HS200\n", + mmc_hostname(host), __func__); + WARN_ON(1); + return -EPERM; + } + + err = mmc_select_hs200(host->card); + if (err) { + pr_err("%s: %s: selecting HS200 failed (%d)\n", + mmc_hostname(host), __func__, err); + return err; + } + + mmc_set_bus_speed(host->card); + + err = mmc_hs200_tuning(host->card); + if (err) { + pr_err("%s: %s: hs200 tuning failed (%d)\n", + mmc_hostname(host), __func__, err); + return err; + } + + if (!(host->card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS400)) { + pr_debug("%s: card does not support HS400\n", + mmc_hostname(host)); + return 0; + } + } + + err = mmc_select_hs400(host->card); + if (err) { + pr_err("%s: %s: select hs400 failed (%d)\n", + mmc_hostname(host), __func__, err); + return err; + } + + return 0; +} + +static int mmc_set_clock_bus_speed(struct mmc_card *card, unsigned long freq) +{ + int err = 0; + + if (freq == MMC_HS200_MAX_DTR) + err = mmc_scale_high(card->host); + else + err = mmc_scale_low(card->host, freq); + + return err; +} + +static inline unsigned long mmc_ddr_freq_accommodation(unsigned long freq) +{ + if (freq == MMC_HIGH_DDR_MAX_DTR) + return freq; + + return freq/2; +} + +/** + * mmc_change_bus_speed() - Change MMC card bus frequency at runtime + * @host: pointer to mmc host structure + * @freq: pointer to desired frequency to be set + * + * Change the MMC card bus frequency at runtime after the card is + * initialized. Callers are expected to make sure of the card's + * state (DATA/RCV/TRANSFER) before changing the frequency at runtime. + * + * If the frequency to change is greater than max. supported by card, + * *freq is changed to max. supported by card. If it is less than min. + * supported by host, *freq is changed to min. supported by host. + * Host is assumed to be calimed while calling this funciton. + */ +static int mmc_change_bus_speed(struct mmc_host *host, unsigned long *freq) +{ + int err = 0; + struct mmc_card *card; + unsigned long actual_freq; + + card = host->card; + + if (!card || !freq) { + err = -EINVAL; + goto out; + } + actual_freq = *freq; + + WARN_ON(!host->claimed); + + /* + * For scaling up/down HS400 we'll need special handling, + * for other timings we can simply do clock frequency change + */ + if (mmc_card_hs400(card) || + (!mmc_card_hs200(host->card) && *freq == MMC_HS200_MAX_DTR)) { + err = mmc_set_clock_bus_speed(card, *freq); + if (err) { + pr_err("%s: %s: failed (%d)to set bus and clock speed (freq=%lu)\n", + mmc_hostname(host), __func__, err, *freq); + goto out; + } + } else if (mmc_card_hs200(host->card)) { + mmc_set_clock(host, *freq); + err = mmc_hs200_tuning(host->card); + if (err) { + pr_warn("%s: %s: tuning execution failed %d\n", + mmc_hostname(card->host), + __func__, err); + mmc_set_clock(host, host->clk_scaling.curr_freq); + } + } else { + if (mmc_card_ddr52(host->card)) + actual_freq = mmc_ddr_freq_accommodation(*freq); + mmc_set_clock(host, actual_freq); + } + +out: + return err; +} + /* * Handle the detection and initialisation of a card. * diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index fe914ff..fc78c09 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -592,6 +592,60 @@ static int sd_set_current_limit(struct mmc_card *card, u8 *status) return 0; } +/** + * mmc_sd_change_bus_speed() - Change SD card bus frequency at runtime + * @host: pointer to mmc host structure + * @freq: pointer to desired frequency to be set + * + * Change the SD card bus frequency at runtime after the card is + * initialized. Callers are expected to make sure of the card's + * state (DATA/RCV/TRANSFER) beforing changing the frequency at runtime. + * + * If the frequency to change is greater than max. supported by card, + * *freq is changed to max. supported by card and if it is less than min. + * supported by host, *freq is changed to min. supported by host. + */ +static int mmc_sd_change_bus_speed(struct mmc_host *host, unsigned long *freq) +{ + int err = 0; + struct mmc_card *card; + + /* + * Assign card pointer after claiming host to avoid race + * conditions that may arise during removal of the card. + */ + card = host->card; + + /* sanity checks */ + if (!card || !freq) { + err = -EINVAL; + goto out; + } + + mmc_set_clock(host, (unsigned int) (*freq)); + + if (!mmc_host_is_spi(card->host) && mmc_card_uhs(card) + && card->host->ops->execute_tuning) { + /* + * We try to probe host driver for tuning for any + * frequency, it is host driver responsibility to + * perform actual tuning only when required. + */ + err = card->host->ops->execute_tuning(card->host, + MMC_SEND_TUNING_BLOCK); + if (err) { + pr_warn("%s: %s: tuning execution failed %d. Restoring to previous clock %lu\n", + mmc_hostname(card->host), __func__, err, + host->clk_scaling.curr_freq); + mmc_set_clock(host, host->clk_scaling.curr_freq); + } + } + +out: + return err; +} + + /* * UHS-I specific initialization procedure */