Hi Jaehoon, > -----Original Message----- > From: Jaehoon Chung [mailto:jh80.ch...@samsung.com] > Sent: Tuesday, January 23, 2018 7:23 AM > To: Siva Durga Prasad Paladugu <siva...@xilinx.com>; u- > b...@lists.denx.de > Cc: Vipul Kumar <vip...@xilinx.com> > Subject: Re: [RFC PATCH] mmc: Skipping the MMC initialization at the boot > time > > Hi Siva, > > On 01/22/2018 08:03 PM, Siva Durga Prasad Paladugu wrote: > > Hi Jaehoon, > > > >> -----Original Message----- > >> From: Jaehoon Chung [mailto:jh80.ch...@samsung.com] > >> Sent: Thursday, January 18, 2018 1:46 PM > >> To: Siva Durga Prasad Paladugu <siva...@xilinx.com>; u- > >> b...@lists.denx.de > >> Cc: Vipul Kumar <vip...@xilinx.com>; Vipul Kumar <vip...@xilinx.com>; > >> Siva Durga Prasad Paladugu <siva...@xilinx.com> > >> Subject: Re: [RFC PATCH] mmc: Skipping the MMC initialization at the > >> boot time > >> > >> On 01/18/2018 02:40 PM, Siva Durga Prasad Paladugu wrote: > >>> From: Vipul Kumar <vipul.ku...@xilinx.com> > >>> > >>> By enabling CONFIG_SKIP_EARLY_MMC_INIT config, user can skip the > >> MMC > >>> initialization at the boot time. After getting the u-boot console, > >>> user can select the device using mmc dev and can communicate with > that. > >>> This is useful where user don't want to perform mmc initialization > >>> while booting and can do explicitly later as per choice. > >> > >> Is there any use-case? What benefit can user have with this config? > >> According to commit-msg, user will choose the mmc device later. > >> Is it same with initializing at booting time? > > Yes, there may be case, where we have both controllers enabled but > > user would like to Communicate with only one at u-boot and this > > selection also depends on environment Or something which will be > > updated from external world then in this case, user will initialize > > Later as per his wish. This may save bootime as it initializes only > > the required one and choice of which one to initialize > > Then did you check how much time can save? I didn’t measured, but it will definitely decrease eventhough it can be minimal. > If user want to save the booting time, will not enter to uboot console? Yes, user doesn’t need to enter u-boot console, he can simply execute boot command as per environment and that env may contain corresponding/required mmc init only.
> Well..I didn't agree about saving the booting time. > > If you need to add this config, could you explain in more detail. > And how many board do enable this config in ./configs/ ? I see it as an option, anyone can enable if they see value for them or need boot time improvement. For me, it's just one config in configs/ as of now. Thanks, Siva > > Best Regards, > Jaehoon Chung > > > > > Thanks, > > Siva > > > >> > >>> > >>> Signed-off-by: Vipul Kumar <vip...@xilinx.com> > >>> Signed-off-by: Siva Durga Prasad Paladugu <siva...@xilinx.com> > >>> --- > >>> common/board_r.c | 4 ++-- > >>> drivers/mmc/Kconfig | 7 +++++++ > >>> 2 files changed, 9 insertions(+), 2 deletions(-) > >>> > >>> diff --git a/common/board_r.c b/common/board_r.c index > >>> 2a9df6b..8727b93 100644 > >>> --- a/common/board_r.c > >>> +++ b/common/board_r.c > >>> @@ -421,7 +421,7 @@ static int initr_onenand(void) } #endif > >>> > >>> -#ifdef CONFIG_MMC > >>> +#if defined(CONFIG_MMC) && > >> !defined(CONFIG_SKIP_EARLY_MMC_INIT) > >>> static int initr_mmc(void) > >>> { > >>> puts("MMC: "); > >>> @@ -768,7 +768,7 @@ static init_fnc_t init_sequence_r[] = { #ifdef > >>> CONFIG_CMD_ONENAND > >>> initr_onenand, > >>> #endif > >>> -#ifdef CONFIG_MMC > >>> +#if defined(CONFIG_MMC) && > >> !defined(CONFIG_SKIP_EARLY_MMC_INIT) > >>> initr_mmc, > >>> #endif > >>> initr_env, > >>> diff --git a/drivers/mmc/Kconfig b/drivers/mmc/Kconfig index > >>> ab0627a..05b1503 100644 > >>> --- a/drivers/mmc/Kconfig > >>> +++ b/drivers/mmc/Kconfig > >>> @@ -40,6 +40,13 @@ config SPL_DM_MMC > >>> > >>> if MMC > >>> > >>> +config SKIP_EARLY_MMC_INIT > >>> + bool "Skip the MMC initialization at boot time" > >>> + help > >>> + Skip the MMC initialization at the boot time. After > >>> +getting the u- > >> boot > >>> + console, user need to set mmc device and after setting the > >>> + mmc > >> dev, user > >>> + can communicate with that device. > >>> + > >>> config ARM_PL180_MMCI > >>> bool "ARM AMBA Multimedia Card Interface and compatible > >> support" > >>> depends on DM_MMC && OF_CONTROL > >>> -- > >>> 2.7.4 > >>> > >>> This email and any attachments are intended for the sole use of the > >> named recipient(s) and contain(s) confidential information that may > >> be proprietary, privileged or copyrighted under applicable law. If > >> you are not the intended recipient, do not read, copy, or forward > >> this email message or any attachments. Delete this email message and > >> any attachments immediately. > >>> > >>> > >>> > > _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot