> -----Original Message----- > From: kyungmin78@xxxxxxxxx [mailto:kyungmin78@xxxxxxxxx] On Behalf Of > Kyungmin Park > Sent: Thursday, December 09, 2010 2:05 PM > To: Dong, Chuanxiao > Cc: linux-mmc@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; cjb@xxxxxxxxxx; > arjan@xxxxxxxxxxxxxxx; alan@xxxxxxxxxxxxxxx; akpm@xxxxxxxxxxxxxxxxxxxx > Subject: Re: [PATCH v4 1/4]enable HW reset capbility > > On Thu, Dec 9, 2010 at 2:40 PM, Dong, Chuanxiao > <chuanxiao.dong@xxxxxxxxx> wrote: > > > > > >> -----Original Message----- > >> From: kyungmin78@xxxxxxxxx [mailto:kyungmin78@xxxxxxxxx] On Behalf Of > >> Kyungmin Park > >> Sent: Thursday, December 09, 2010 1:24 PM > >> To: Dong, Chuanxiao > >> Cc: linux-mmc@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; cjb@xxxxxxxxxx; > >> arjan@xxxxxxxxxxxxxxx; alan@xxxxxxxxxxxxxxx; akpm@xxxxxxxxxxxxxxxxxxxx > >> Subject: Re: [PATCH v4 1/4]enable HW reset capbility > >> > >> On Wed, Dec 1, 2010 at 9:49 PM, Chuanxiao Dong <chuanxiao.dong@xxxxxxxxx> > >> wrote: > >> > From d3be0b4fe8e8a40294830dfd8d0543d1e957fd29 Mon Sep 17 00:00:00 > 2001 > >> > From: Chuanxiao Dong <chuanxiao.dong@xxxxxxxxx> > >> > Date: Wed, 1 Dec 2010 19:14:02 +0800 > >> > Subject: [PATCH 1/4] enable HW reset caps of MMC card if card supports > >> > > >> > HW reset capbility enable bit is byte 162 in card EXT_CSD > >> > register, only version4.4 card or later can support to enable > >> > this feature. > >> > > >> > HW reset feature can be used to reset eMMC card when occures > >> > timeout errors during read/write/erase. > >> > > >> > Signed-off-by: Chuanxiao Dong <chuanxiao.dong@xxxxxxxxx> > >> > --- > >> > drivers/mmc/core/mmc.c | 29 +++++++++++++++++++++++++++++ > >> > include/linux/mmc/card.h | 1 + > >> > include/linux/mmc/mmc.h | 1 + > >> > 3 files changed, 31 insertions(+), 0 deletions(-) > >> > > >> > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > >> > index 77f93c3..85cc7f6 100644 > >> > --- a/drivers/mmc/core/mmc.c > >> > +++ b/drivers/mmc/core/mmc.c > >> > @@ -310,6 +310,10 @@ static int mmc_read_ext_csd(struct mmc_card > *card) > >> > ext_csd[EXT_CSD_SEC_FEATURE_SUPPORT]; > >> > card->ext_csd.trim_timeout = 300 * > >> > ext_csd[EXT_CSD_TRIM_MULT]; > >> > + /* > >> > + * check Hardware reset cap > >> Check hardware. > >> > + */ > >> > + card->ext_csd.rst = ext_csd[EXT_CSD_RST]; > >> > } > >> > > >> > if (ext_csd[EXT_CSD_ERASED_MEM_CONT]) > >> > @@ -484,6 +488,31 @@ static int mmc_init_card(struct mmc_host *host, > u32 > >> ocr, > >> > } > >> > > >> > /* > >> > + * eMMC4.4 version card has HW reset capbility. > >> capability. > >> > + * Enable this feature here: > >> > + * RST_N_FUNCTION register is W/R, one time programmable > >> Use RST_n_FUNCTION as spec. > >> > + * 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 && > >> it should be card->ext_csd.rev >= 5 since 4 is obsolete. > >> > >> Thank you, > >> Kyungmin Park > > > > Thanks, Park. I will fix this. > > And by the way, I noticed mmc_read_ext_csd function also used > card->ext_csd.rev >=4. Is there some other reason for this kind of using? Or it is > just because at that time the value 4 has not be obsolete yet....? > > Maybe need to fix it also. > > And remaining patches also need to fix 'capability' typo. Thanks. Will pay more attention on this. And will resubmit new version for review. Thanks > >> > + card->ext_csd.rst == 0) { > >> > + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, > >> > + EXT_CSD_RST, 1); > >> > + > >> > + if (err && err != -EBADMSG) > >> > + goto free_card; > >> > + > >> > + if (err) { > >> > + printk(KERN_WARNING "%s: switch to rst > enable > >> " > >> > + "failed %d\n", > >> > + mmc_hostname(card->host), > err); > >> > + err = 0; > >> > + } else > >> > + card->ext_csd.rst = 1; > >> > + } > >> > + > >> > + /* > >> > * Activate high speed (if supported) > >> > */ > >> > if ((card->ext_csd.hs_max_dtr != 0) && > >> > 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/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 */ > >> > -- > >> > 1.6.6.1 > >> > > >> > -- > >> > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > >> > the body of a message to majordomo@xxxxxxxxxxxxxxx > >> > More majordomo info at http://vger.kernel.org/majordomo-info.html > >> > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
