From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Rini Date: Thu, 19 Feb 2015 09:03:30 -0500 Subject: [U-Boot] [PATCH 3/4] mmc: exynos dwmmc: check boot mode before init dwmmc In-Reply-To: <54E46E81.6030303@samsung.com> References: <1424178544-28632-1-git-send-email-p.marczak@samsung.com> <1424178544-28632-4-git-send-email-p.marczak@samsung.com> <54E46E81.6030303@samsung.com> Message-ID: <20150219140330.GI25879@bill-the-cat> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Wed, Feb 18, 2015 at 11:50:41AM +0100, Przemyslaw Marczak wrote: > Hello Simon, > > On 02/18/2015 06:02 AM, Simon Glass wrote: > >Hi Przemyslaw, > > > >On 17 February 2015 at 06:09, Przemyslaw Marczak wrote: > >>Before this commit, the mmc devices were always registered > >>in the same order. So dwmmc channel 0 was registered as mmc 0, > >>channel 1 as mmc 1, etc. > >>In case of possibility to boot from more then one device, > >>the CONFIG_SYS_MMC_ENV_DEV should always point to right mmc device. > >> > >>This can be achieved by init boot device as first, so it will be > >>always registered as mmc 0. Thanks to this, the 'saveenv' command > >>will work fine for all mmc boot devices. > >> > >>Exynos based boards usually uses mmc host channels configuration: > >>- 0, or 0+1 for 8 bit - as a default boot device (usually eMMC) > >>- 2 for 4bit - as an optional boot device (usually SD card slot) > >> > >>And usually the boot order is defined by OM pin configuration, > >>which can be changed in a few ways, eg. > >>- Odroid U3 - eMMC card insertion -> first boot from eMMC > >>- Odroid X2/XU3 - boot priority jumper > >> > >>By this commit, Exynos dwmmc driver will check the OM pin configuration, > >>and then try to init the boot device and register it as mmc 0. > > > >I think a better way to do this would be to make > >CONFIG_SYS_MMC_ENV_DEV support an option where the device can be > >selected at run-time. > > > >However that would probably be better done when the drive rmodel > >conversion is complete. > > > >So this seems a reasonable patch given where we are. > > > >Reviewed-by: Simon Glass > > > > This was just a quick solution to solve the issue on XU3, when the > same binary can boot from sd or eMMC slots. XU3 isn't unique in this regard. "am335x_evm" binaries runs on 4 very different boards and we still just have to say that sometimes we default to ENV in a place that isn't workable. -- Tom -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 836 bytes Desc: Digital signature URL: