From patchwork Tue Nov 2 12:36:03 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Chuanxiao.Dong" X-Patchwork-Id: 297202 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id oA2CbN9r004349 for ; Tue, 2 Nov 2010 12:37:23 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751854Ab0KBMhX (ORCPT ); Tue, 2 Nov 2010 08:37:23 -0400 Received: from mga14.intel.com ([143.182.124.37]:63815 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751822Ab0KBMhT convert rfc822-to-8bit (ORCPT ); Tue, 2 Nov 2010 08:37:19 -0400 Received: from azsmga001.ch.intel.com ([10.2.17.19]) by azsmga102.ch.intel.com with ESMTP; 02 Nov 2010 05:37:18 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.58,281,1286175600"; d="scan'208,223";a="343544115" Received: from unknown (HELO intel.com) ([172.16.120.128]) by azsmga001.ch.intel.com with ESMTP; 02 Nov 2010 05:37:17 -0700 Date: Tue, 2 Nov 2010 20:36:03 +0800 From: "Chuanxiao.Dong" To: cjb@laptop.org Cc: linux-mmc@vger.kernel.org Subject: [PATCH v2 1/2]mmc: implemented eMMC4.4 hardware reset feature in mmc core layer Message-ID: <20101102123603.GB1313@intel.com> Reply-To: "Chuanxiao.Dong" MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Tue, 02 Nov 2010 12:37:23 +0000 (UTC) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 8f86d70..0c8882e 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -209,6 +209,8 @@ static void mmc_wait_done(struct mmc_request *mrq) */ void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq) { + struct mmc_card *card = host->card; + DECLARE_COMPLETION_ONSTACK(complete); mrq->done_data = &complete; @@ -217,6 +219,31 @@ void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq) mmc_start_request(host, mrq); wait_for_completion(&complete); + + /* as MMC4.4 standard says, when some data timeout conditions + * occur, HC need to do a hardware reset for eMMC4.4 card. + * If the card is eMMC4.4 card && data error is timeout, + * do the following things: + * 1. let host controller do a specific hardware reset for eMMC + * card (trigger RST_n signal). + * 2. after reset done, reinit eMMC4.4 card. + * */ + if (mrq->data && card && + mrq->data->error == -ETIMEDOUT && + card->ext_csd.rst == 1) { + int err = 1; + if (host->ops->hardware_reset && + host->bus_ops->reinit) { + err = host->ops->hardware_reset(host); + if (err) + pr_warn("MMC card reset failed, no reinit\n"); + else + err = host->bus_ops->reinit(host); + } + + if (err) + pr_warn("cannot reset and reinit eMMC4.4 card\n"); + } } EXPORT_SYMBOL(mmc_wait_for_req); diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h index 77240cd..232a3d9 100644 --- a/drivers/mmc/core/core.h +++ b/drivers/mmc/core/core.h @@ -24,6 +24,7 @@ struct mmc_bus_ops { int (*resume)(struct mmc_host *); int (*power_save)(struct mmc_host *); int (*power_restore)(struct mmc_host *); + int (*reinit)(struct mmc_host *); }; void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops); diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 995261f..123b203 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -237,6 +237,8 @@ static int mmc_read_ext_csd(struct mmc_card *card) } } + card->ext_csd.rst = ext_csd[EXT_CSD_RST]; + card->ext_csd.rev = ext_csd[EXT_CSD_REV]; if (card->ext_csd.rev > 5) { printk(KERN_ERR "%s: unrecognised EXT_CSD revision %d\n", @@ -484,6 +486,25 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, } /* + * eMMC4.4 version card has HW reset capbility. + * Enable this feature here: + * RST_N_FUNCTION register is W/R, one time programmable + * or readable. + * So need to enable this register only once after power on + * */ + if (card->csd.mmca_vsn >= CSD_SPEC_VER_4 && + card->ext_csd.rev >= 4 && + card->ext_csd.rst != 1) { + /* Be careful, EXT_CSD_RST register is one + * time programmable + * */ + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, + EXT_CSD_RST, 1); + if (!err) + card->ext_csd.rst = 1; + } + + /* * Activate high speed (if supported) */ if ((card->ext_csd.hs_max_dtr != 0) && @@ -699,6 +720,28 @@ static int mmc_awake(struct mmc_host *host) return err; } +static int mmc_reinit_card(struct mmc_host *host) +{ + int err; + + BUG_ON(!host); + BUG_ON(!host->card); + + if (host->f_min > 400000) { + pr_warning("%s: Minimum clock frequency too high for " + "identification mode\n", mmc_hostname(host)); + host->ios.clock = host->f_min; + } else + host->ios.clock = 400000; + mmc_set_clock(host, host->ios.clock); + + err = mmc_init_card(host, host->ocr, host->card); + if (err) + printk(KERN_ERR "%s: err %d\n", __func__, err); + + return err; +} + static const struct mmc_bus_ops mmc_ops = { .awake = mmc_awake, .sleep = mmc_sleep, @@ -707,6 +750,7 @@ static const struct mmc_bus_ops mmc_ops = { .suspend = NULL, .resume = NULL, .power_restore = mmc_power_restore, + .reinit = mmc_reinit_card, }; static const struct mmc_bus_ops mmc_ops_unsafe = { @@ -717,6 +761,7 @@ static const struct mmc_bus_ops mmc_ops_unsafe = { .suspend = mmc_suspend, .resume = mmc_resume, .power_restore = mmc_power_restore, + .reinit = mmc_reinit_card, }; static void mmc_attach_bus_ops(struct mmc_host *host) diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h index 8ce0827..ebee676 100644 --- a/include/linux/mmc/card.h +++ b/include/linux/mmc/card.h @@ -54,6 +54,7 @@ struct mmc_ext_csd { unsigned int sec_trim_mult; /* Secure trim multiplier */ unsigned int sec_erase_mult; /* Secure erase multiplier */ unsigned int trim_timeout; /* In milliseconds */ + unsigned int rst; /* hardware reset enable bit */ }; struct sd_scr { diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 6d87f68..6e9eba8 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -117,6 +117,11 @@ struct mmc_host_ops { /* optional callback for HC quirks */ void (*init_card)(struct mmc_host *host, struct mmc_card *card); + + /* HW reset callback, used for eMMC 4.4 new feature. + * when occurs data timeout, HC will need to reset eMMC4.4 card + * */ + int (*hardware_reset)(struct mmc_host *host); }; struct mmc_card; diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h index 956fbd8..b7ab0da 100644 --- a/include/linux/mmc/mmc.h +++ b/include/linux/mmc/mmc.h @@ -251,6 +251,7 @@ struct _mmc_csd { * EXT_CSD fields */ +#define EXT_CSD_RST 162 /* onetime programmable R/W */ #define EXT_CSD_ERASE_GROUP_DEF 175 /* R/W */ #define EXT_CSD_ERASED_MEM_CONT 181 /* RO */ #define EXT_CSD_BUS_WIDTH 183 /* R/W */