Ulf, On Fri, Apr 29, 2016 at 12:21 AM, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote: > On 29 April 2016 at 01:06, Douglas Anderson <dianders@xxxxxxxxxxxx> wrote: >> This series picks patches from various different places to produce what >> I consider the best solution to getting consistent mmc and mmcblk >> ordering. >> >> Why consistent ordering and why not just use UUIDs? IMHO consistent >> ordering solves a few different problems: >> >> 1. For poor, feeble-minded humans like me, have sane numbering for >> devices helps a lot. When grepping through dmesg it's terribly handy >> if a given SDMMC device has a consistent number. I know that I can >> do "dmesg | grep mmc0" or "dmesg | grep mmcblk0" to find info about >> the eMMC. I know that I can do "dmesg | grep mmc1" to find info >> about the SD card slot. I don't want it to matter which one probed >> first, I don't want it to matter if I'm working on a variant of the >> hardware that has the SD card slot disabled, and I don't want to care >> what my boot device was. Worrying about what device number I got >> increases my cognitive load. >> >> 2. There are cases where it's not trivially easy during development to >> use the UUID. Specifically I work a lot with coreboot / depthcharge >> as a BIOS. When configured properly, that BIOS has a nice feature to >> allow you to fetch the kernel and kernel command line from TFTP by >> pressing Ctrl-N. In this particular case the BIOS doesn't actually >> know which disk I'd like for my root filesystem, so it's not so easy >> for it to put the right UUID into the command line. For this >> purpose, knowing that "mmcblk0" will always refer to eMMC is handy. >> >> >> Jaehoon Chung (1): >> Documentation: mmc: Document mmc aliases >> >> Stefan Agner (2): >> mmc: read mmc alias from device tree >> mmc: use SD/MMC host ID for block device name ID >> >> Documentation/devicetree/bindings/mmc/mmc.txt | 11 +++++++++++ >> drivers/mmc/card/block.c | 3 ++- >> drivers/mmc/core/host.c | 25 ++++++++++++++++++++----- >> 3 files changed, 33 insertions(+), 6 deletions(-) >> >> -- >> 2.8.0.rc3.226.g39d4020 >> > > I believe you need to re-base this patchset as things have changed. > > Currently the mmc host index that gets picked at host registration > point, will also be given to the corresponding mmc block device index. > That's probably solving most of your concerns, but I am open to extend > this to cover aliases as well, as to allow it to be *really* > deterministic. OK, got it. Send new patch now. :) PTAL. -- 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
